1. Field of the Invention
This invention relates to illumination devices and, more particularly, to illumination devices comprising a plurality of light emitting diode (LED) elements and to interference-resistant methods for monitoring and adjusting the illumination devices during operation.
2. Description of the Relevant Art
The following descriptions and examples are provided as background only and are intended to reveal information that is believed to be of possible relevance to the present invention. No admission is necessarily intended, or should be construed, that any of the following information constitutes prior art impacting the patentable character of the subjected mater claimed herein.
Lamps and displays using LEDs (light emitting diodes) for illumination are becoming increasingly popular in many different markets. LEDs provide a number of advantages over traditional light sources such as incandescent and fluorescent light bulbs, including low power consumption, long lifetime, lack of hazardous materials, and additional specific advantages for different applications. When used for general illumination, LEDs provide the opportunity to adjust the color (e.g., from white, to blue, to green, etc.) or the color temperature (e.g., from “warm white” to “cool white”) to produce different lighting effects. In addition, LEDs are rapidly replacing the Cold Cathode Fluorescent Lamps (CCFL) conventionally used in many display applications (such as LCD backlights), due to the smaller form factor and wider color gamut provided by LEDs. Organic LEDs (OLEDs), which use arrays of multi-colored organic LEDs to produce light for each display pixel, are also becoming popular for many types of display devices.
LED devices may combine different colors of LEDs within the same package to produce a multi-colored LED device, or lamp. An example of a multi-colored LED device is one in which two or more different colors of LEDs are combined to produce white or near-white light. There are many different types of white light lamps on the market, some of which combine red, green and blue (RGB) LEDs, red, green, blue and yellow (RGBY) LEDs, white and red (WR) LEDs, RGBW LEDs, etc. By combining different colors of LEDs within the same package, and driving the differently colored LEDs with different drive currents, these lamps may be configured to generate white light or near-white light within a wide gamut of color points or color temperatures ranging from “warm white” (e.g., roughly 2600K-3700K), to “neutral white” (e.g., 3700K-5000K) to “cool white” (e.g., 5000K-8300K).
Although LEDs have many advantages over conventional light sources, a disadvantage of LEDs is that their output characteristics tend to vary over temperature, process and time. For example, it is generally known that the luminous flux, or the perceived power of light emitted by an LED, is directly proportional to the drive current supplied thereto. In many cases, the luminous flux of an LED is controlled by increasing/decreasing the drive current supplied to the LED to correspondingly increase/decrease the luminous flux. However, the luminous flux generated by an LED for a given drive current does not remain constant over temperature and time, and gradually decreases with increasing temperature and as the LED ages over time. Furthermore, the luminous flux tends to vary from batch to batch, and even from one LED to another in the same batch, due to process variations.
LED manufacturers try to compensate for process variations by sorting or binning the LEDs based on factory measured characteristics, such as chromaticity (or color), luminous flux and forward voltage. However, binning alone cannot compensate for changes in LED output characteristics due to aging and temperature fluctuations during use of the LED device. In order to maintain a constant (or desired) luminous flux, it is usually necessary to adjust the drive current supplied to the LED to account for temperature variations and aging effects.
As discussed further below, such adjustment may involve compensation measurements of one or more LED elements within a lamp. Interference from a nearby lamp can cause errors in such measurements for a given lamp, potentially resulting in incorrect compensation for the lamp. It would therefore be desirable to develop interference-resistant compensation methods for LED illumination devices, and illumination devices incorporating such methods.
The following description of various embodiments of an illumination device and a method for controlling an illumination device is not to be construed in any way as limiting the subject matter of the appended claims.
A method is provided herein for controlling an illumination device comprising multiple emission light emitting diodes (LED) elements. An “LED element” as used herein refers to either a single LED or a chain of serially connected LEDs supplied with the same drive current. An “emission LED element” as used herein is an LED element configured for light emission, as opposed to, for example, an LED configured as a light detector. An embodiment of the method includes operating one or more of the multiple emission LED elements at a respective substantially continuous drive current sufficient to produce illumination, bringing to a level insufficient to produce illumination the respective drive current of all except one of the emission LED elements within the illumination device for the duration of a first measurement interval, and bringing to a level insufficient to produce illumination the respective drive current of all except one of the emission LED elements for the duration of a second measurement interval subsequent to the first measurement interval. The first measurement interval is one of a first series of measurement intervals interspersed with periods of operating the emission LED elements to produce illumination, and the second measurement interval is one of a second series of measurement intervals interspersed with periods of operating the emission LED elements to produce illumination. The first series of measurement intervals and second series of measurement intervals are separated by respective first and second offsets from a timing reference. In an embodiment, the method further includes discontinuing use of the first series of measurement intervals at a time subsequent to the end of the first measurement interval.
The method may further include applying a drive current sufficient to produce illumination to one of the emission LED elements during each of the first and second measurement intervals, and monitoring a measurement photocurrent induced in a measurement photodetector within the lamp while the drive current is applied. In an embodiment, the method also includes determining that a result of monitoring the measurement photocurrent during the first measurement interval is outside of an expected range. In an embodiment, this determining includes comparing the result to a previously stored result. In another embodiment, bringing to a level insufficient to produce illumination the respective drive current of all except one of the emission LED elements for the duration of the second measurement interval is in response to the determination that the result of monitoring the measurement photocurrent during the first measurement interval is outside of the expected range. In another embodiment the method also includes, in response to the determination that the result of monitoring the measurement photocurrent during the first measurement interval is outside of the expected range, repeating, during an additional one of the first series of measurement intervals, applying the drive current sufficient to produce illumination to the one of the emission LED elements and said monitoring the measurement photocurrent induced in the measurement photodetector. The method may further include determining whether a predetermined number of out-of-range measurements using the first series of measurement intervals has occurred. In such an embodiment, bringing to a level insufficient to produce illumination the respective drive current of all except one of the emission LED elements for the duration of a second measurement interval may be in response to a determination that the predetermined number of out-of-range measurements using the first series of measurement intervals has occurred.
In a further embodiment, the method includes, for each of the first and second measurement intervals, bringing the drive current applied to the one of the emission LED elements to a level insufficient to produce illumination for a portion of the measurement interval, such that the respective drive currents of all of the emission LED elements within the illumination device are at a level insufficient to produce illumination for the portion of the measurement interval. The method may further include monitoring a background photocurrent induced in the measurement photodetector during the portion of the measurement interval with the drive currents of all of the emission LED elements at a level insufficient to produce illumination, and subtracting the background photocurrent from the measurement photocurrent. In an embodiment, the result of monitoring a measurement photocurrent during the first measurement interval includes a result of subtracting the background photocurrent from the measurement photocurrent for the first measurement interval.
In addition to the method embodiments described above, an illumination device is contemplated herein. In one embodiment, the device includes multiple emission LED elements, one or more photodetectors, and a control circuit operably coupled to the multiple emission LED elements and the one or more photodetectors. In an embodiment, the control circuit is adapted to operate one or more of the multiple emission LED elements at a respective substantially continuous drive current to produce illumination, bring to a level insufficient to produce illumination the respective drive current of all except one of the emission LED elements within the illumination device for the duration of a first measurement interval, and bring to a level insufficient to produce illumination the respective drive currents of all except one of the emission LED elements for the duration of a second measurement interval subsequent to the first measurement interval. The first measurement interval is one of a first series of measurement intervals interspersed with periods of operating the emission LED elements to produce illumination, and the second measurement interval is one of a second series of measurement intervals interspersed with periods of operating the emission LED elements to produce illumination. The first series of measurement intervals and second series of measurement intervals are separated by respective first and second offsets from a timing reference.
In a further embodiment, the illumination device also includes a timing reference generator operatively coupled to the control circuit and adapted to generate a periodic timing reference. In such an embodiment, the control circuit may be further adapted to generate the first series of measurement intervals synchronized to the timing reference with a first offset from the timing reference and generate the second series of measurement intervals synchronized to the timing reference with a second offset from the timing reference. In another embodiment, the control circuit is adapted to discontinue use of the first series of measurement intervals at a time subsequent to the end of the first measurement interval.
In another embodiment, the illumination device also includes an LED driver and receiver circuit operably coupled to the multiple emission LED elements, the one or more photodetectors, and the control circuit. In such an embodiment, the control circuit is adapted to use the LED driver and receiver circuit to adjust the respective drive currents of the emission LED elements. In a further embodiment, the control circuit is adapted to use the LED driver and receiver circuit to, during each of said first measurement interval and said second measurement interval, bring to a level insufficient to produce illumination the respective drive currents of all except one of the emission LED elements, apply a drive current sufficient to produce illumination to the one of the emission LED elements, and monitor a measurement photocurrent induced in the measurement photodetector while the drive current is applied. In a still further embodiment, the control circuit is further adapted to determine whether a result of monitoring the measurement photocurrent during the first measurement interval is outside of an expected range. The control circuit may also be adapted to bring to a level insufficient to produce illumination the respective drive currents of all except one of the emission LED elements for the duration of the second measurement interval in response to a determination that the result is outside of the expected range. In an embodiment, the illumination device also includes a storage medium operably coupled to the control circuit, and the control circuit is adapted to compare the result of monitoring the measurement photocurrent during the first measurement interval with a result previously stored in the storage medium. In another embodiment, the control circuit is further adapted to determine whether a predetermined number of out-of-range measurements using the first series of measurement intervals has occurred.
In a further embodiment of the illumination device contemplated herein, the control circuit is further adapted to, for each of the first and second measurement intervals, bring the drive current applied to the one of the emission LED elements to a level insufficient to produce illumination for a portion of the measurement interval, such that the respective drive currents of all of the emission LED elements within the illumination device are at a level insufficient to produce illumination for the portion of the measurement interval. In such an embodiment, the control circuit may further be adapted to monitor a background photocurrent induced in the measurement photodetector during the portion of the measurement interval and subtract the background photocurrent from the measurement photocurrent. In a still further embodiment, the control circuit is further adapted to determine whether a result of subtracting the background photocurrent from the measurement photocurrent during the first measurement interval is outside of an expected range.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the accompanying drawings.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.
An LED generally comprises a chip of semiconducting material doped with impurities to create a p-n junction. As in other diodes, current flows easily from the p-side, or anode, to the n-side, or cathode, but not in the reverse direction. Charge-carriers—electrons and holes—flow into the junction from electrodes with different voltages. When an electron meets a hole, it falls into a lower energy level, and releases energy in the form of a photon (i.e., light). The wavelength of the light emitted by the LED, and thus its color, depends on the band gap energy of the materials forming the p-n junction of the LED.
Red and yellow LEDs are commonly composed of materials (e.g., AlInGaP) having a relatively low band gap energy, and thus produce longer wavelengths of light. For example, most red and yellow LEDs have a peak wavelength in the range of approximately 610-650 nm and approximately 580-600 nm, respectively. On the other hand, green and blue LEDs are commonly composed of materials (e.g., GaN or InGaN) having a larger band gap energy, and thus, produce shorter wavelengths of light. For example, most green and blue LEDs have a peak wavelength in the range of approximately 515-550 nm and approximately 450-490 nm, respectively.
In some cases, a “white” LED may be formed by covering or coating, e.g., a violet or blue LED having a peak emission wavelength of about 400-490 nm with a phosphor (e.g., YAG), which down-converts the photons emitted by the blue LED to a lower energy level, or a longer peak emission wavelength, such as about 525 nm to about 600 nm. In some cases, such an LED may be configured to produce substantially white light having a correlated color temperature (CCT) of about 3000K. However, a skilled artisan would understand how different colors of LEDs and/or different phosphors may be used to produce a “white” LED with a potentially different CCT.
When two or more differently colored LEDs are combined within a single package, the spectral content of the individual LEDs is combined to produce blended light. In some cases, differently colored LEDs may be combined to produce white or near-white light within a wide gamut of color points or CCTs ranging from “warm white” (e.g., roughly 2600K-3000K), to “neutral white” (e.g., 3000K-4000K) to “cool white” (e.g., 4000K-8300K). Examples of white light illumination devices include, but are not limited to, those that combine red, green and blue (RGB) LEDs, red, green, blue and yellow (RGBY) LEDs, white and red (WR) LEDs, and RGBW LEDs.
The illumination devices disclosed herein may in certain embodiments include one or more emitter modules, which may also be called lamps. An emitter module has a plurality of LED elements and one or more photodetectors combined into a package. As noted above, an LED element may be either a single LED or a chain of serially connected LEDs supplied with the same drive current. An LED element configured for its junction(s) to have sufficient forward bias for light emission may be referred to herein as an “emission LED element.” An LED may also be configured as a photodetector, typically by applying zero bias or reverse bias to the LED junction and collecting photocurrent induced by incident light. In an embodiment, multiple LEDs configured as photodetectors may be connected in parallel so that their photocurrents can be combined.
Although not limited to such, the present invention is particularly well suited to multi-colored illumination devices in which two or more different colors of LEDs are combined to produce blended white or near-white light, since the output characteristics of differently colored LEDs vary differently over drive current, temperature and time. The present invention is also particularly well suited to illumination devices (i.e., tunable illumination devices) that enable the target dimming level and/or the target chromaticity setting to be changed by adjusting the drive currents supplied to one or more of the LEDs, since changes in drive current inherently affect the lumen output, color and temperature of the illumination device. These tunable illumination devices should all produce the same color and color rendering index (CRI) when set to a particular dimming level and chromaticity setting (or color set point) on a standardized chromaticity diagram.
A chromaticity diagram maps the gamut of colors the human eye can perceive in terms of chromaticity coordinates and spectral wavelengths. An example of a chromaticity diagram is shown in
In the 1931 Commission Internationale de l'Êclairage (CIE) Chromaticity Diagram of
The color of an incandescent black body as a function of temperature in Kelvin is also plotted on the diagram of
Although an illumination device is typically configured to produce a range of white or near-white color temperatures arranged along the blackbody curve (e.g., about 2500K to 5000K), some illumination devices may be configured to produce any color within the color gamut, such as triangular color gamut 18 of
In general, the target chromaticity of the illumination device may be changed by adjusting the drive current levels (in current dimming) or duty cycle (in PWM dimming) supplied to one or more of the emission LEDs. For example, an illumination device comprising RGB LEDs may be configured to produce “warmer” white light by increasing the drive current supplied to the red LEDs and decreasing the drive currents supplied to the blue and/or green LEDs. Since adjusting the drive currents also affects the lumen output and temperature of the illumination device, the target chromaticity must be carefully calibrated and controlled to ensure that the actual chromaticity equals the target value.
U.S. application Ser. Nos. 13/970,990 and 14/314,530, co-pending with the present application and commonly owned and/or subject to assignment with the present application, describe methods of compensation for variation in quantities including temperature and drive current, and illumination devices employing such methods. Approaches described in these applications to compensating for variations in luminous flux from LEDs, such as the effects illustrated by
Exemplary compensation approaches for an illumination device including multiple emission LED elements and at least one photodetector are illustrated by
In the embodiment of
The plot in
Another example of a compensation method is illustrated by
The plot in
As shown by the examples above and described further in the co-pending applications referenced herein, it can be advantageous to take measurements during brief interruptions in illumination by an LED illumination device. When used in conjunction with calibration data, such measurements allow monitoring and correction of variations from desired settings. In one embodiment, a series of intervals such as intervals 610 of
In an alternative embodiment, compensation using intervals such as intervals 610 of
The lower diagram of
As discussed above in connection with
The upper diagram of
The lower diagram of
In an embodiment, the detector used to measure induced ambient photocurrent IA is the same detector used to measure total photocurrent IT during interval portion 1104 when the target LED element is driven at an operative current level. In this way, the ambient photocurrent induced during measurement of the tested LED element may be most accurately accounted for by the ambient photocurrent detected during interval portion 1106 when the tested LED element is off. In some embodiments, a separate detector may be used for ambient light detection, alternatively or in addition to a detector used for ambient detection during photocurrent measurements. A separate detector for ambient light measurement may be particularly useful, for example, in embodiments for which target settings of the illumination device are adjusted depending on ambient light conditions.
The importance of the ambient subtraction of
A situation in which the subtraction technique illustrated in
The lower diagram of
In the example of
“Non-constant illumination” as used herein refers to illumination having a substantial variation with time during a measurement interval, or during a portion of a measurement interval in which detection of background or ambient illumination is being performed. In an embodiment, a substantial variation is a variation that would result in a significant error for a photocurrent measurement conducted during the same interval. The size of the variation that would result in a significant error depends on the relative magnitudes of photocurrents induced by a measured LED element and by the external illumination in the photodetector used for the photocurrent measurement.
A further illustration of how the kind of interference shown in
During interval 1210 of
In an alternative embodiment in which Lamp A were taking a photocurrent measurement during interval 1210 rather than a forward voltage measurement, the magnitude of the externally-induced photocurrent may be significant by comparison to the measured current. However, the constant illumination provided by the illumination from Lamp B during interval 1210 could be successfully subtracted out if a photocurrent measurement were taken by Lamp A during that interval. This subtraction would correspond to the situation illustrated in
During each of intervals 1220 and 1240, one of the lamps is performing a photocurrent measurement on an LED element, while the other lamp is performing a forward voltage measurement. During interval 1240, for example, a forward voltage measurement Vf2A of emission LED element 2 of Lamp A is performed, while a photocurrent measurement Iph2B measures the photocurrent induced in a detector of Lamp B by operation of emission LED element 2 of Lamp B. In an embodiment, forward voltage measurements of emission LED elements are taken using non-operative levels of drive current, meaning drive current levels insufficient to produce significant illumination from the LED. In such an embodiment, the forward voltage measurement taken using one lamp would not be expected to interfere with the photocurrent measurement taken using the other lamp. Whether there is interference in the opposite direction—i.e., whether the photocurrent measurement of Lamp B interferes with the forward voltage measurement of Lamp A—depends upon the relative magnitudes of the forward bias induced current in the measured LED element of Lamp A and the photocurrent induced in that LED element by the illumination from Lamp B. This can depend on various factors, as discussed above in the discussion of interval 1210.
During interval 1230, however, a photocurrent measurement is taken in both Lamp A and Lamp B. Because illumination is produced by both of these measurements, errors will be introduced into each measurement, and any resulting drive current adjustments, to the extent that illumination produced by one lamp is detectable by the other lamp. Interference from these two photocurrent measurements cannot be mitigated using ambient subtraction techniques. An attempt to subtract interference-related photocurrent from the photocurrent measured by each lamp would in one embodiment lead to a situation similar to that shown in
In an embodiment of a method described herein for avoiding interference, detection is performed during one or more intervals before a photocurrent measurement is performed during one of the intervals. In a further embodiment, the detection during one or more intervals is performed before any measurement associated with compensation of an illumination device is performed. Photocurrent measurements, or in some embodiments any measurements, are initiated after detection has been performed for enough intervals to indicate that interference from compensation measurements of another lamp is unlikely. In an embodiment, a photodetector is used to determine whether outside illumination is present that is not constant throughout the measurement interval.
In an embodiment, the number of intervals used for detection depends on the particular sequences of measurements used by the illumination device performing the method and by any potentially interfering devices. As noted above in the discussion of
As an example, consider an emitter module including 4 LED elements and at least one photodetector. The photodetector(s) may be dedicated photodetectors or may in some embodiments be emission LEDs configured at certain times as photodetectors. In an embodiment, such an emitter module may use a sequence of 12 measurements for compensation. For example, 4 of the compensation measurements could be forward voltage measurements for each of the 4 LED elements. Another 4 measurements could be photocurrent measurements for each of the 4 LED elements using one dedicated photodetector. Another 2 measurements could be photocurrent measurements for two of the LED elements using an additional photodetector. The remaining 2 measurements could be forward voltages across each of two detectors. In this example, 6 of the 12 compensation measurements are photocurrent measurements.
In one embodiment of the above example, it may be expected that any interfering illumination devices will also be configured to use a sequence of 12 compensation measurements, 6 of which are photocurrent measurements. If the particular sequence of measurements that an interfering device may be configured to use is not known, one approach would be to detect for 12 measurement intervals before starting compensation measurements. If no non-constant illumination is detected during any of the 12 intervals, it is likely that no nearby illumination device is performing compensation measurements. In another embodiment, if it is expected that 6 of the compensation measurements performed by an interfering device are photocurrent measurements, detection could be performed for 7 intervals before starting compensation measurements if no non-constant illumination is detected. If another device were performing compensation measurements including six photocurrent measurements, one of the 6 photocurrent measurements would be expected to occur within a sequence of 7 intervals. In still another embodiment, if the 6 photocurrent measurements were expected to be uniformly spaced within the 12-measurement sequence (in this case, every other measurement of the 12 measurements would be a photocurrent measurement), 2 consecutive intervals in which no non-constant illumination is detected may be sufficient to indicate that no nearby device is likely to be currently performing compensation measurements.
In a further embodiment of the emitter module example described above, the various photocurrent measurements included in the compensation measurement sequence are not equally detectable. Some of the photocurrent measurements may be easier to detect, and more likely to cause interference, than others. This may particularly be the case in embodiments with emitter modules containing emission LED elements emitting different colors of light. Certain combinations of LED element and detector may result in significantly higher photocurrent signals. Measurements using these emitter/detector combinations may be referred to as “beacon” measurements. The magnitude of the photocurrent signal for a particular measurement depends on factors including the luminous flux emitted by the LED element, the sensitivity of the detector, and how well the emitter and detector are matched in terms of spectral response. As an example, one measurement for a multi-color emission module that may result in a relatively high photocurrent signal is measurement of a green emission LED element using a detector configured to detect red light (in an embodiment, the detector is a red LED configured as a detector).
For the example described above of an emitter module having 12 compensation measurements including 6 photocurrent measurements, consider an embodiment in which two of the photocurrent measurements result in significantly higher photocurrent signals than the other photocurrent measurements. In such an embodiment, the number of detection intervals used before starting compensation measurements may be chosen such that one of these higher-photocurrent signals would be expected to occur if a nearby device is performing compensation measurements. If the sequence of the measurements is not known, for example, 11 intervals without detection of a non-constant illumination would be needed to be certain that one of the 2 “beacon” measurements should have occurred if interfering measurements are in progress. Alternatively, if the 2 “beacon” measurements are known to be evenly spaced within the measurement sequence (6 measurements apart, in this example), 6 intervals without detection of a non-constant illumination would be sufficient before beginning compensation measurements.
The embodiments described above relating to determining a number of detection intervals to use before starting compensation measurements can be illustrated using a timing diagram such as that of
An alternative approach to that of
In an embodiment for which non-sensitive measurements are performed during an overall detection sequence but detection is not performed during the intervals in which non-sensitive measurements are taken, the expected measurement sequence of any interfering devices would need to include enough consecutive higher-intensity measurements that a measurement sequence performed by a nearby device would be detected during one of the intervals when detection is performed. For example, in an embodiment of
The timing diagrams of
In an embodiment, detection of a non-constant illumination during a detection interval causes an illumination device to discontinue the detection sequence and return to driving the emission LED elements in the device to provide continuous illumination. In such an embodiment, the illumination device may be returned to a continuous illumination state uninterrupted by detection intervals or measurement intervals, similar to illumination periods 1010 of
When the detection sequence is discontinued after detection of a non-constant illumination during a detection interval, the measurement control circuit of the illumination device waits, in one embodiment, for some delay time before restarting the detection sequence. In a further embodiment, the delay time is a randomized delay time. After waiting for the delay time, the measurement control circuit may in one embodiment start again at the beginning of the detection sequence that was aborted upon detection of the non-continuous illumination. Alternatively, in some embodiments the detection sequence may be picked up at a point after the beginning of the sequence. In an embodiment, the detection sequence is started again at the point in the sequence when the non-continuous illumination was previously detected. Such an embodiment may be suitable, for example, in a sequence such as that of
As an alternative to the above-described embodiments of suspending a detection sequence and resuming detection after a delay, another approach to handling detection of a non-constant illumination during a detection interval may be suitable in certain embodiments. In an embodiment for which the sequence of measurements expected to be performed by an interfering device is known, detection of a non-constant illumination during one or more detection intervals may allow a measurement control circuit to predict which upcoming intervals will or will not contain interfering measurements. In such an embodiment, the measurement control circuit may be able to select a starting interval for its own measurement sequence such that each of the two devices is able to complete its respective measurement sequence without obtaining erroneous results. An example of such a scenario is illustrated by
The pair of timing diagrams in
During interval 1410, Lamp B carries out a forward voltage measurement Vf1B of a first emission LED element. Even in an embodiment for which Lamps A and B are in close proximity and/or facing one another, Lamp A does not detect any significant non-constant illumination from the measurement by Lamp B as long as the drive current for the measurement Vf1B is at a level too low to result in illumination. During interval 1420, however, Lamp A does, in this embodiment, detect a non-constant illumination associated with the measurement by Lamp B of photocurrent Iph1B induced in a detector when the first LED element is illuminated. In the embodiment of
In the embodiment of
The approach of
The discussion above of
In an embodiment, measurement errors are detected by checking to see whether a measured value is within an expected range. In a further embodiment, the expected range is based on the most recently stored value of the measured quantity. In such an embodiment, the expected range accounts for the magnitude of expected variations in the measured quantity caused by factors such as LED aging or temperature change of an LED element. In one embodiment, a measured value is outside of the expected range if it varies by more than about 5 percent from the most recently stored value of the measured quantity. In another embodiment, a measured value is outside of the expected range if it varies by more than about 3 percent from the most recently stored value. In yet another embodiment, a measured value is outside of the expected range if it varies by more than about 2 percent from the most recently stored value. Other thresholds for considering a measurement out-of-range may be used, depending on factors such as the volatility of the particular quantity being measured and the degree of accuracy required for compensation and control of the illumination device. If the measured value is outside of the expected range, the measured value is discarded rather than stored. In an embodiment, the measurement sequence continues after an out-of range measurement is detected, with in-range measurements stored while out-of-range measurements are discarded. In an alternative embodiment, an out-of-range measurement causes the measurement sequence to be suspended. In such an embodiment, the control circuit of the illumination device may wait for a delay time and then attempt the measurement sequence again. The new attempt may start at the beginning of the sequence, or alternatively may start with the measurement that was out of range. In another embodiment in which the measurement sequence is suspended after an out-of-range measurement, the control circuit may wait for a delay time and then begin a detection sequence before attempting measurements again.
Checking for whether a measurement is in range is in some embodiments combined with methods described above for detection during some number of intervals before performing compensation measurements. In an alternative embodiment, measurements are performed without any detection intervals beforehand, with the measured values checked for being out of an expected range. In still another embodiment, measurements are initially performed without detection beforehand, but if an out-of-range value is obtained, a detection method as described above is employed before resuming measurements. In some embodiments, checking for whether a measurement is in range is performed only for interference-sensitive measurements such as photocurrent measurements. In other embodiments, all measured values are checked for being within an expected range.
Approaches described above to avoiding interference from nearby illumination devices when performing compensation measurements include performing detection to predict interference-free intervals for taking measurements, checking measured values to determine whether measurement error has occurred, and suspending and reattempting detection and/or measurements in the event that interference is detected. Another approach to avoiding interference is to use a different set of intervals than that used by a potentially interfering device. In an embodiment of this approach, one set of periodic intervals is established having a first offset time from a periodic timing reference, while another set of periodic intervals is established having a second offset time from the timing reference. An exemplary timing diagram illustrating such an embodiment is shown in
In the embodiment of
If one emitter module is configured to perform compensation measurements using a first set of measurement intervals such as those of waveform 1530, and another emitter module is configured to perform its compensation measurements using a second set of measurement intervals such as those of waveform 1540, measurements by the two emitter modules will not interfere with one another because the two sets of measurement intervals are displaced in time. In an embodiment, lamps or emitter modules that are to be placed in close proximity are assigned to different sets of measurement intervals. Such an embodiment may be particularly suitable for illumination fixtures containing multiple lamps or emitter modules. In another embodiment, an emitter module may initially use one set of measurement intervals and later switch to another set of measurement intervals if interference from nearby devices is encountered. This type of embodiment may be suitable in the case of an individual emitter module, since the configuration of lamps that it may be operated in proximity to is typically not known.
In the example described above of a 60 Hz AC signal and a 360 Hz timing reference signal used in the embodiment of
In one embodiment having a timing reference signal with frequency of an integer N times the frequency of an AC reference signal (like the embodiment of
Flowcharts of exemplary methods of performing interference-resistant compensation measurements using the approaches described above are shown in
In the embodiment of
If a photocurrent measurement is performed, the emission LED element to be tested is turned on using the desired drive current during a first part of the measurement interval (decision 1610 and step 1622). In one embodiment, the emission LED element is turned on for half of the measurement interval. In other embodiments, the emission LED element is turned on for a different fraction of the measurement interval. The photocurrent on a detector within the illumination device or emitter module is measured during the part of the measurement interval when the tested LED element is turned on (step 1624). The detector used in the measurement may be referred to herein as a measurement photodetector and the photocurrent detected by the measurement may be referred to as a measurement photocurrent. During a second part of the measurement interval, the tested LED element is turned off (while the other emission LED elements remain turned off) (step 1626). The ambient or background photocurrent induced in the detector is measured during this second part of the measurement interval (step 1628). As noted in the discussion of
When both the photocurrent induced by the driven LED element and the ambient photocurrent have been measured, the ambient photocurrent is subtracted from the photocurrent induced by the driven emission LED element to obtain a corrected photocurrent (step 1630). In an embodiment, this subtraction is done in hardware. The corrected photocurrent is then checked to see whether it is within an expected range (decision 1632). In an embodiment, the expected range is based on a target value of the photocurrent, or on the most recent reliable measured value. The expected range is in some embodiments set to be larger than the expected variation of the photocurrent caused by temperature variation or LED aging. If the corrected photocurrent is within the expected range, it is stored (step 1614) and the measurement counter is incremented (step 1616).
In the embodiment of
At the end of the measurement interval, one or more of the emission LED elements are again operated to produce the desired illumination (step 1618). As compensation measurements are taken and evaluated, the drive currents applied to the respective LED elements to obtain desired illumination may be adjusted, as described further in the co-pending applications referenced herein. In the embodiment of
Variations of the method of
An exemplary flowchart for a method of detecting during a series of intervals prior to starting compensation measurements is shown in
If no non-constant illumination is detected during the interval (decisions 1640 and 1654), a “free” interval is recorded by incrementing the free interval counter and contiguous free interval counter (step 1658). The emission LED elements are turned back on to resume illumination at the end of the interval (step 1656). In the embodiment of
If non-constant illumination is detected during an interval, the collision counter is incremented and the contiguous free interval counter is reset (decision 1640 and steps 1644 and 1646). The emission LED elements are turned back on as usual to resume illumination at the end of the interval (step 1642). If a maximum number of collisions has not been reached, the control circuit waits for a delay time before attempting detection again (decision 1648, steps 1650 and 1636). In an embodiment, the delay time is a randomized delay time. In a further embodiment, the delay time is determined using the collision counter, such that after each successive collision the delay time is progressively longer. For example, in one embodiment the delay time is randomized within a specific range, and that range is set to progressively higher values after each successive collision. In a further embodiment, the delay time increases after each successive collision at an exponential rate.
In an embodiment of the method of
If measurements by other devices continue to be detected during repeated attempts separated by delay times, a maximum number of collisions may be reached (decision 1648). At this point, the control circuit changes to a different series of measurement intervals, separated from a timing reference by a different offset time (step 1652). Such sets of intervals are described above in connection with waveforms 1530 and 1540 in
Variations of the method of
An alternative method of detecting prior to starting compensation measurements is illustrated by the flowchart of
Although not shown in
In an embodiment, determinations as to whether an interfering measurement sequence is known and whether overlapping, but non-interfering, measurements may be conducted are done using configuration information such as that shown in
Sequence information 1708 includes the sequence of compensation measurements performed for each device. In the embodiment of
In the embodiment of
The remaining information in configuration data 1700 characterizes the measurement sequence for each device in ways that may be helpful in determining whether an overlapping measurement sequence can be formed. In an embodiment, an overlapping but not interfering measurement sequence can be conducted as long as any sensitive measurements in one sequence of measurements performed by one device are not performed in the same interval as an interfering measurement in another sequence of measurements performed by a nearby device. Because in the embodiment of
Within configuration information 1700, number of sensitive measurements 1712 indicates the number of sensitive measurements within each sequence. In the embodiment of
Same-sequence non-interfering offset 1716 refers to a number of intervals by which a device performing a measurement sequence needs to offset (i.e., delay) its sequence with respect to another device performing the same sequence. For example, if a Brand A device detected a photocurrent measurement performed by an interfering device and it was known that the interfering device was also a Brand A device, it would be known from Brand A configuration information 1702 that the next measurement, if any, by the interfering device would be a non-interfering (non-photocurrent) measurement. The detecting device could not start its measurement sequence during that next interval, because the non-interfering first measurement of its sequence would align with the non-interfering next measurement of the interfering sequence. Because much of the Brand A measurement sequence alternates between interfering and non-interfering measurements, aligning two non-interfering measurements between the devices would likely cause alignment of two interfering (and sensitive) measurements in a subsequent interval of the sequence. If the detecting device delays one more interval before starting its sequence, however, any remaining sensitive (photocurrent) measurements by the interfering device should align with a non-sensitive measurement by the detecting device. This delay has the effect of offsetting, or shifting, the measurement sequence of the detecting device by an odd number of intervals from that of the interfering device.
Using a similar analysis for the measurement sequence of the Brand B device, it can be seen from configuration information 1704 that an offset 1716 of either 2 or 6 intervals would allow another Brand B device to perform an overlapping measurement sequence. Similarly, for the sequence of the Brand C device, an offset of between 4 and 8 intervals would allow another Brand C device to perform an overlapping but non-interfering measurement sequence.
Another quantity included in configuration information 1700 is interval range 1718 including all sensitive measurements. The Brand A sequence has a range 1718 of 7 intervals, from interval 2 to interval 8, in which all of the sensitive measurements are performed. The Brand B sequence has a range 1718 of 6 intervals, from interval 3 to interval 8. For the brand C device, all of the sensitive measurements are performed within a range 1718 of 4 intervals.
Also included in configuration information 1700 is interval range 1720 of the most contiguous non-sensitive measurements within a measurement sequence. Interval range 1720 is 5 for the sequence of Brand A, from interval 9 to interval 1 (assuming that the measurement sequence is continually repeated). For the measurement sequence of Brand B, interval range 1720 is 6 intervals, from interval 9 to interval 2. For the sequence of Brand C, interval range 1720 is eight intervals, from interval 5 to interval 12. Interval ranges 1718 and 1720 may be useful in determining whether different measurement sequences, such as those used by different device manufacturers, may be overlapped without interference. For example, the measurement sequences of the three devices of configuration information 1700 are too different to allow non-interfering overlap of two different device sequences using a simple one- or two-interval shift. In some cases, however, a larger shift can align a contiguous range of non-sensitive measurements in one sequence with the entire range of sensitive measurements in another sequence. To illustrate, the measurement sequence of Brand A in
Returning to the method of
In some embodiments, the control circuit is able to determine a measurement sequence used by the interfering device by monitoring the collision, free interval, and contiguous free interval counters during successive intervals. For example, a sequence of a detected photocurrent measurement (i.e., a collision), followed by a non-sensitive measurement (which increments the free interval and contiguous free interval counters), followed by another sensitive measurement (which increments the collision counter and clears the contiguous free interval counter) indicates that the sequence of Brand A is used by the interfering device. A sequence of three sensitive measurements in a row, on the other hand, would indicate that the sequence of Brand C is used by the interfering device.
If the sequence of the interfering measurements is known, the control circuit determines whether an overlapping, but non-interfering, measurement sequence by the controlled device is possible (decision 1670). In an embodiment, configuration information such as that of
In the embodiment of
Exemplary Embodiments of Improved Illumination Devices
The improved methods described herein for controlling an illumination device may be used within substantially any LED illumination device having a plurality of emission LED elements and one or more photodetectors. As described in more detail below, the improved methods described herein may be implemented within an LED illumination device in the form of hardware, software or a combination of both.
Illumination devices, which benefit from the improved methods described herein, may have substantially any form factor including, but not limited to, parabolic lamps (e.g., PAR 20, 30 or 38), linear lamps, flood lights and mini-reflectors. In some cases, the illumination devices may be installed in a ceiling or wall of a building, and may be connected to an AC mains or some other AC power source. However, a skilled artisan would understand how the improved methods described herein may be used within other types of illumination devices powered by other power sources (e.g., batteries or solar energy).
Exemplary embodiments of an improved illumination device are described with reference to
A computer-generated representation of a top view of an exemplary emitter module 1820 that may be included within the linear lamp 1810 of
In the illustrated embodiment, emitter module 1920 includes an array of emission LEDs 1930 and a plurality of dedicated photodetectors 1950, all of which are mounted on a common substrate and encapsulated within a primary optics structure (e.g., a dome) 1940. In some embodiments, the array of emission LEDs 1930 may include a number of differently colored chains of LEDS, wherein each chain is configured for producing illumination at a different peak emission wavelength. According to one embodiment, the array of emission LEDs 1930 may include a chain of four red LEDs, a chain of four green LEDs, a chain of four blue LEDs, and a chain of four white or yellow LEDs. Each chain of LEDs is coupled in series and driven with the same drive current. In some embodiments, the individual LEDs in each chain may be scattered about the array, and arranged so that no color appears twice in any row, column or diagonal, to improve color mixing within the emitter module 1920.
In the exemplary embodiment of
The illumination devices shown in
In the illustrated embodiment, illumination device 2000 comprises a plurality of emission LED elements 2045 and one or more dedicated photodetectors 2050. The emission LED elements 2045, in this example, comprise four chains of any number of LEDs. In typical embodiments, each chain may have 2 to 4 LEDs of the same color, which are coupled in series and configured to receive the same drive current. In one example, the emission LED elements 2045 may include a chain of red LEDs, a chain of green LEDs, a chain of blue LEDs, and a chain of white or yellow LEDs. However, the methods and devices described herein are not limited to any particular number of LED chains, any particular number of LEDs within the chains, or any particular color or combination of LED colors.
Similarly, the methods and devices described herein are not limited to any particular type, number, color, combination or arrangement of photodetectors. In one embodiment, the one or more dedicated photodetectors 2050 may include a small red, orange or yellow LED. In another embodiment, the one or more dedicated photodetectors 128 may include one or more small red LEDs and one or more small green LEDs. In some embodiments, one or more of the dedicated photodetector(s) 2050 shown in
In addition to including one or more emitter modules, illumination device 2000 includes various hardware and software components, which are configured for powering the illumination device and controlling the light output from the emitter module(s). In one embodiment, the illumination device is connected to AC mains 2005, and includes an AC/DC converter 2010 for converting AC mains power (e.g., 120V or 240V) to a DC voltage (VDC). As shown in
In the illustrated embodiment, PLL 2020 locks to the AC mains frequency (e.g., 50 or 60 HZ) and produces a high speed clock (CLK) signal and a synchronization signal (SYNC). The CLK signal provides the timing for control circuit 2035 and LED driver and receiver circuit 2040. In one example, the CLK signal frequency is in the tens of MHz range (e.g., 23 MHz), and is precisely synchronized to the AC Mains frequency and phase. The SYNC signal is used by the control circuit 2035 to create the timing of the intervals used for the detection and compensation measurements described above. In one example, the SYNC signal frequency is equal to the AC Mains frequency (e.g., 50 or 60 HZ) and also has a precise phase alignment with the AC Mains. In another embodiment, the SYNC signal frequency is an integral multiple of the AC mains frequency. In an embodiment, timing reference signal 1520 of
In some embodiments, a wireless interface 2025 may be included and used to calibrate the illumination device 2000 during manufacturing. As discussed in the co-pending applications referenced herein, an external calibration tool (not shown in
Wireless interface 2025 is not limited to receiving only calibration data, and may be used for communicating information and commands for many other purposes. For example, wireless interface 2025 could be used during normal operation to communicate commands, which may be used to control the illumination device 2000, or to obtain information about the illumination device 2000. For instance, commands may be communicated to the illumination device 2000 via the wireless interface 2025 to turn the illumination device on/off, to control the dimming level and/or color set point of the illumination device, to initiate the calibration procedure, or to store calibration results in memory. In other examples, wireless interface 2025 may be used to obtain status information or fault condition codes associated with illumination device 2000.
In some embodiments, wireless interface 2025 could operate according to ZigBee, WiFi, Bluetooth, or any other proprietary or standard wireless data communication protocol. In other embodiments, wireless interface 2025 could communicate using radio frequency (RF), infrared (IR) light or visible light. In alternative embodiments, a wired interface could be used, in place of the wireless interface 2025 shown, to communicate information, data and/or commands over the AC mains or a dedicated conductor or set of conductors.
Using the timing signals received from PLL 2020, the control circuit 2035 calculates and produces values indicating the desired drive current to be used for each LED chain 2045. This information may be communicated from the control circuit 2035 to the LED driver and receiver circuit 2040 over a serial bus conforming to a standard, such as SPI or I2C, for example. In addition, the control circuit 2035 may provide a latching signal that instructs the LED driver and receiver circuit 2040 to simultaneously change the drive currents supplied to each of the LEDs 2045 to prevent brightness and color artifacts.
Control circuit 2035 may be configured for determining the respective drive currents needed to achieve a desired luminous flux and/or a desired chromaticity for the illumination device in accordance with one or more compensation methods as described above in connection with
In some embodiments, the control circuit 2035 may determine the respective drive currents and perform the interference-related operations described herein by executing program instructions stored within the storage medium 2030. In one embodiment, the storage medium may be a non-volatile memory, and may be configured for storing the program instructions along with a table of calibration values used in the compensation methods and a data structure including configuration information such as that of
In general, the LED driver and receiver circuit 2040 may include a number (N) of driver blocks 2115 equal to the number of emission LED chains 2045 included within the illumination device. In the exemplary embodiment discussed herein, LED driver and receiver circuit 2040 comprises four driver blocks 2115, each configured to produce illumination from a different one of the emission LED chains 2045. The LED driver and receiver circuit 2040 also comprises the circuitry needed to measure ambient temperature (optional), the detector and/or emitter forward voltages, and the detector photocurrents, and to adjust the LED drive currents accordingly. Each driver block 2115 receives data indicating a desired drive current from the control circuit 2035, along with a latching signal indicating when the driver block 2115 should change the drive current.
As shown in
As noted above, some embodiments of the invention may use one of the emission LEDs (e.g., a green emission LED), at times, as a photodetector. In such embodiments, the driver blocks 2115 may include additional circuitry for measuring the photocurrents (Iph_d2), which are induced across an emission LED, when the emission LED is configured for detecting incident light. For example, each driver block 2115 may include a transimpedance amplifier 2130, which generally functions to convert an input current to an output voltage proportional to a feedback resistance. As shown in
When measuring the photocurrents (Iph_d2) induced by an emission LED, the buck converters 2120 connected to all other emission LEDs should be turned off to avoid visual artifacts produced by LED current transients. In addition, the buck converter 2120 coupled to the emission LED under test should also be turned off to prevent switching noise within the buck converter from interfering with the photocurrent measurements. Although turned off, the Vdr output of the buck converter 2120 coupled to the emission LED under test is held to a particular value (e.g., about 2-3.5 volts times the number of emission LEDs in the chain) by the capacitor within LC filter 2145. When this voltage (Vdr) is supplied to the anode of emission LED under test and the positive terminal of the transimpedance amplifier 2130, the transimpedance amplifier produces an output voltage (relative to Vdr) that is supplied to the positive terminal of difference amplifier 2135. Difference amplifier 2135 compares the output voltage of transimpedance amplifier 2130 to Vdr and generates a difference signal, which corresponds to the photocurrent (Iph_d2) induced across the LED chain 2045(a).
In addition to including a plurality of driver blocks 2115, the LED driver and receiver circuit 2040 may include one or more receiver blocks 2150 for measuring the forward voltages (Vfd) and photocurrents (Iph_d1 or Iph_d2) induced across the one or more dedicated photodetectors 2050. Although only one receiver block 2150 is shown in
In the illustrated embodiment, receiver block 2150 comprises a voltage source 2155, which is coupled for supplying a DC voltage (Vdr) to the anode of the dedicated photodetector 2050 coupled to the receiver block, while the cathode of the photodetector 2050 is connected to current source 2160. When photodetector 2050 is configured for obtaining forward voltage (Vfd), the controller 2190 supplies a “Detector_On” signal to the current source 2160, which forces a fixed drive current (Idrv) equal to the value provided by the “Detector Current” signal through photodetector 2050.
When obtaining detector forward voltage (Vfd) measurements, current source 2160 is configured for drawing a relatively small amount of drive current (Idrv) through photodetector 2050. The voltage drop (Vfd) produced across photodetector 2050 by that current is measured by difference amplifier 2175, which produces a signal equal to the forward voltage (Vfd) drop across photodetector 2050. As noted above, the drive current (Idrv) forced through photodetector 2050 by the current source 2160 is generally a relatively small, non-operative drive current. In the embodiment in which four dedicated photodetectors 2050 are coupled in parallel, the non-operative drive current may be roughly 1 mA. However, smaller/larger drive currents may be used in embodiments that include fewer/greater numbers of photodetectors, or embodiments that do not connect the photodetectors in parallel.
Similar to driver block 2115, receiver block 2150 also includes circuitry for measuring the photocurrents (Iph_d1 or Iph_d2) induced on photodetector 2050 by ambient light, as well as light emitted by the emission LEDs. As shown in
As noted above, some embodiments of the invention may scatter the individual LEDs within each chain of LEDs 2045 about the array of LEDs, so that no two LEDs of the same color exist in any row, column or diagonal (see, e.g.,
As shown in
In some embodiments, the LED driver and receiver circuit 2040 may include an optional temperature sensor 2195 for taking ambient temperature (Ta) measurements. In such embodiments, multiplexor 2180 may also be coupled for multiplexing the ambient temperature (Ta) with the forward voltage and photocurrent measurements sent to the ADC 2185. In some embodiments, the temperature sensor 2195 may be a thermistor, and may be included on the driver circuit chip for measuring the ambient temperature surrounding the LEDs, or a temperature from the heat sink of the emitter module. If the optional temperature sensor 2195 is included, the output of the temperature sensor may be used in some embodiments to determine if a significant change in temperature is detected. In some embodiments detection of a significant change in temperature may cause compensation measurements to be initiated.
One implementation of an improved illumination device 2000 has now been described in reference to
An exemplary block diagram of circuit components for an illumination device including multiple emitter modules is shown in
In the embodiment of
In the illustrated embodiment, emitter board 2204 comprises six emitter modules 2212 and six interface circuits 2210. Interface circuits 2210 communicate with controller 2208 over the digital control bus and produce the drive currents supplied to the LEDs within the emitter modules 2212.
In an embodiment, the circuit components on power supply board 2202 are implemented in a similar manner as the power supply and control circuitry shown in
One implementation of an improved illumination device has now been described in reference to
It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide an improved illumination device and methods for avoiding interference-related errors when compensating individual LEDs in the illumination device for variations in quantities such as drive current and temperature. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. It is intended, therefore, that the following claims be interpreted to embrace all such modifications and changes and, accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.
The present application is a reissue of U.S. Pat. No. 9,345,097, issued on May 17, 2016 from U.S. application Ser. No. 14/510,266, filed Oct. 9, 2014, which is a continuation-in-part of the following: U.S. application Ser. No. 13/970,990 filed Aug. 20, 2013; U.S. application Ser. No. 14/097,339 filed Dec. 5, 2013; and U.S. application Ser. No. 14/314,530 filed Jun. 25, 2014; each of which is hereby incorporated by reference in their entirety and for all purposes as if completely and fully set forth herein.
Number | Name | Date | Kind |
---|---|---|---|
4029976 | Fish et al. | Jun 1977 | A |
4402090 | Gfeller et al. | Aug 1983 | A |
4713841 | Porter et al. | Dec 1987 | A |
4744672 | Turskey et al. | May 1988 | A |
4745402 | Auerbach | May 1988 | A |
4809359 | Dockery | Feb 1989 | A |
5018057 | Biggs et al. | May 1991 | A |
5103466 | Bazes | Apr 1992 | A |
5181015 | Marshall et al. | Jan 1993 | A |
5193201 | Tymes | Mar 1993 | A |
5218356 | Knapp | Jun 1993 | A |
5299046 | Spaeth et al. | Mar 1994 | A |
5317441 | Sidman | May 1994 | A |
5541759 | Neff et al. | Jul 1996 | A |
5619262 | Uno | Apr 1997 | A |
5657145 | Smith | Aug 1997 | A |
5797085 | Beuk et al. | Aug 1998 | A |
5905445 | Gurney et al. | May 1999 | A |
6016038 | Mueller et al. | Jan 2000 | A |
6067595 | Lindenstruth | May 2000 | A |
6069929 | Yabe et al. | May 2000 | A |
6084231 | Popat | Jul 2000 | A |
6094014 | Bucks et al. | Jul 2000 | A |
6094340 | Min | Jul 2000 | A |
6108114 | Gilliland et al. | Aug 2000 | A |
6127783 | Pashley et al. | Oct 2000 | A |
6147458 | Bucks et al. | Nov 2000 | A |
6150774 | Mueller et al. | Nov 2000 | A |
6234645 | Borner et al. | May 2001 | B1 |
6234648 | Borner et al. | May 2001 | B1 |
6250774 | Begemann et al. | Jun 2001 | B1 |
6333605 | Grouev et al. | Dec 2001 | B1 |
6344641 | Blalock et al. | Feb 2002 | B1 |
6356774 | Bernstein et al. | Mar 2002 | B1 |
6359712 | Kamitani | Mar 2002 | B1 |
6384545 | Lau | May 2002 | B1 |
6396815 | Greaves et al. | May 2002 | B1 |
6414661 | Shen et al. | Jul 2002 | B1 |
6441558 | Muthu et al. | Aug 2002 | B1 |
6448550 | Nishimura | Sep 2002 | B1 |
6495964 | Muthu et al. | Dec 2002 | B1 |
6498440 | Stam et al. | Dec 2002 | B2 |
6513949 | Marshall et al. | Feb 2003 | B1 |
6577512 | Tripathi et al. | Jun 2003 | B2 |
6617795 | Bruning | Sep 2003 | B2 |
6636003 | Rahm et al. | Oct 2003 | B2 |
6639574 | Scheibe | Oct 2003 | B2 |
6664744 | Dietz | Dec 2003 | B2 |
6692136 | Marshall et al. | Feb 2004 | B2 |
6741351 | Marshall et al. | May 2004 | B2 |
6753661 | Muthu et al. | Jun 2004 | B2 |
6788011 | Mueller et al. | Sep 2004 | B2 |
6806659 | Mueller et al. | Oct 2004 | B1 |
6831569 | Wang et al. | Dec 2004 | B2 |
6831626 | Nakamura et al. | Dec 2004 | B2 |
6853150 | Clauberg et al. | Feb 2005 | B2 |
6879263 | Pederson et al. | Apr 2005 | B2 |
6965205 | Piepgras et al. | Nov 2005 | B2 |
6969954 | Lys | Nov 2005 | B2 |
6975079 | Lys et al. | Dec 2005 | B2 |
7006768 | Franklin | Feb 2006 | B1 |
7014336 | Ducharme et al. | Mar 2006 | B1 |
7038399 | Lys et al. | May 2006 | B2 |
7046160 | Pederson et al. | May 2006 | B2 |
7072587 | Dietz et al. | Jul 2006 | B2 |
7088031 | Brantner et al. | Aug 2006 | B2 |
7119500 | Young | Oct 2006 | B2 |
7135824 | Lys et al. | Nov 2006 | B2 |
7161311 | Mueller et al. | Jan 2007 | B2 |
7166966 | Naugler, Jr. et al. | Jan 2007 | B2 |
7194209 | Robbins et al. | Mar 2007 | B1 |
7233115 | Lys | Jun 2007 | B2 |
7233831 | Blackwell | Jun 2007 | B2 |
7252408 | Mazzochette et al. | Aug 2007 | B2 |
7255458 | Ashdown | Aug 2007 | B2 |
7256554 | Lys | Aug 2007 | B2 |
7262559 | Tripathi et al. | Aug 2007 | B2 |
7294816 | Ng et al. | Nov 2007 | B2 |
7315139 | Selvan et al. | Jan 2008 | B1 |
7319298 | Jungwirth et al. | Jan 2008 | B2 |
7329998 | Jungwirth | Feb 2008 | B2 |
7330002 | Joung | Feb 2008 | B2 |
7330662 | Zimmerman | Feb 2008 | B2 |
7352972 | Franklin | Apr 2008 | B2 |
7358706 | Lys | Apr 2008 | B2 |
7359640 | Onde et al. | Apr 2008 | B2 |
7362320 | Payne et al. | Apr 2008 | B2 |
7372859 | Hall et al. | May 2008 | B2 |
7391406 | Yamamoto et al. | Jun 2008 | B2 |
7400310 | LeMay | Jul 2008 | B2 |
7445340 | Conner et al. | Nov 2008 | B2 |
7511695 | Furukawa et al. | Mar 2009 | B2 |
7525611 | Zagar et al. | Apr 2009 | B2 |
7553033 | Seki | Jun 2009 | B2 |
7554514 | Nozawa | Jun 2009 | B2 |
7573210 | Ashdown et al. | Aug 2009 | B2 |
7583901 | Nakagawa et al. | Sep 2009 | B2 |
7606451 | Morita | Oct 2009 | B2 |
7607798 | Panotopoulos | Oct 2009 | B2 |
7619193 | Deurenberg | Nov 2009 | B2 |
7649527 | Cho et al. | Jan 2010 | B2 |
7656371 | Shimizu et al. | Feb 2010 | B2 |
7659672 | Yang | Feb 2010 | B2 |
7683864 | Lee et al. | Mar 2010 | B2 |
7701151 | Petrucci et al. | Apr 2010 | B2 |
7705541 | Watanabe et al. | Apr 2010 | B2 |
7733488 | Johnson | Jun 2010 | B1 |
7737936 | Daly | Jun 2010 | B2 |
7801600 | Carbunaru et al. | Sep 2010 | B1 |
7828479 | Aslan et al. | Nov 2010 | B1 |
8013538 | Zampini et al. | Sep 2011 | B2 |
8018135 | Van De Ven et al. | Sep 2011 | B2 |
8035603 | Furukawa et al. | Oct 2011 | B2 |
8040299 | Kretz et al. | Oct 2011 | B2 |
8044899 | Ng et al. | Oct 2011 | B2 |
8044918 | Choi | Oct 2011 | B2 |
8057072 | Takenaka et al. | Nov 2011 | B2 |
8075182 | Dai et al. | Dec 2011 | B2 |
8076869 | Shatford et al. | Dec 2011 | B2 |
8159150 | Ashdown et al. | Apr 2012 | B2 |
8174197 | Ghanem et al. | May 2012 | B2 |
8174205 | Myers et al. | May 2012 | B2 |
8264171 | Domer | Sep 2012 | B1 |
8283876 | Ji | Oct 2012 | B2 |
8299722 | Melanson | Oct 2012 | B2 |
8358075 | Sejkora | Jan 2013 | B2 |
8362707 | Draper et al. | Jan 2013 | B2 |
8471496 | Knapp | Jun 2013 | B2 |
8521035 | Knapp et al. | Aug 2013 | B2 |
8556438 | McKenzie et al. | Oct 2013 | B2 |
8569974 | Chobot | Oct 2013 | B2 |
8595748 | Haggerty et al. | Nov 2013 | B1 |
8624527 | Meir et al. | Jan 2014 | B1 |
8633655 | Kao et al. | Jan 2014 | B2 |
8653758 | Radermacher et al. | Feb 2014 | B2 |
8659237 | Archenhold | Feb 2014 | B2 |
8680787 | Veskovic | Mar 2014 | B2 |
8704666 | Baker, Jr. | Apr 2014 | B2 |
8721115 | Ing et al. | May 2014 | B2 |
8749172 | Knapp | Jun 2014 | B2 |
8773032 | May et al. | Jul 2014 | B2 |
8791647 | Kesterson et al. | Jul 2014 | B2 |
8816600 | Elder | Aug 2014 | B2 |
8911160 | Seo et al. | Dec 2014 | B2 |
9084310 | Bedell et al. | Jul 2015 | B2 |
9155155 | Ho et al. | Oct 2015 | B1 |
9210750 | Van der Veen et al. | Dec 2015 | B2 |
9237620 | Knapp et al. | Jan 2016 | B1 |
9247605 | Ho | Jan 2016 | B1 |
9332598 | Ho et al. | May 2016 | B1 |
9337925 | Pickard et al. | May 2016 | B2 |
9345097 | Ho et al. | May 2016 | B1 |
9360174 | Dong et al. | Jun 2016 | B2 |
9392660 | Dias et al. | Jul 2016 | B2 |
9392663 | Knapp et al. | Jul 2016 | B2 |
9485813 | Lewis et al. | Nov 2016 | B1 |
9497808 | Murata et al. | Nov 2016 | B2 |
9500324 | Dong | Nov 2016 | B2 |
9510416 | Dias et al. | Nov 2016 | B2 |
9538619 | Swatsky et al. | Jan 2017 | B2 |
9557214 | Ho | Jan 2017 | B2 |
9578724 | Knapp | Feb 2017 | B1 |
9651632 | Knapp | May 2017 | B1 |
9736895 | Dong et al. | Aug 2017 | B1 |
9736903 | Lewis | Aug 2017 | B2 |
9769899 | Ho | Sep 2017 | B2 |
9888543 | Chitta et al. | Feb 2018 | B2 |
9954435 | Knauss et al. | Apr 2018 | B2 |
10595372 | Ho et al. | Mar 2020 | B2 |
20010020123 | Diab et al. | Sep 2001 | A1 |
20010030668 | Erten et al. | Oct 2001 | A1 |
20020014643 | Kubo et al. | Feb 2002 | A1 |
20020033981 | Keller et al. | Mar 2002 | A1 |
20020047624 | Stam et al. | Apr 2002 | A1 |
20020049933 | Nyu | Apr 2002 | A1 |
20020134908 | Johnson | Sep 2002 | A1 |
20020138850 | Basil et al. | Sep 2002 | A1 |
20020171608 | Kanai et al. | Nov 2002 | A1 |
20030103413 | Jacobi, Jr. et al. | Jun 2003 | A1 |
20030122749 | Booth, Jr. et al. | Jul 2003 | A1 |
20030133491 | Shih | Jul 2003 | A1 |
20030179721 | Shurmantine et al. | Sep 2003 | A1 |
20040044709 | Cabrera et al. | Mar 2004 | A1 |
20040052076 | Mueller et al. | Mar 2004 | A1 |
20040052299 | Jay et al. | Mar 2004 | A1 |
20040101312 | Cabrera | May 2004 | A1 |
20040136682 | Watanabe | Jul 2004 | A1 |
20040201793 | Anandan et al. | Oct 2004 | A1 |
20040220922 | Lovison et al. | Nov 2004 | A1 |
20040257311 | Kanai et al. | Dec 2004 | A1 |
20050004727 | Remboski et al. | Jan 2005 | A1 |
20050030203 | Sharp et al. | Feb 2005 | A1 |
20050030267 | Tanghe et al. | Feb 2005 | A1 |
20050053378 | Stanchfield et al. | Mar 2005 | A1 |
20050077838 | Blumel | Apr 2005 | A1 |
20050110777 | Geaghan et al. | May 2005 | A1 |
20050169643 | Franklin | Aug 2005 | A1 |
20050200292 | Naugler, Jr. et al. | Sep 2005 | A1 |
20050207157 | Tani | Sep 2005 | A1 |
20050242742 | Cheang et al. | Nov 2005 | A1 |
20050265731 | Keum et al. | Dec 2005 | A1 |
20060061288 | Zwanenburg et al. | Mar 2006 | A1 |
20060145887 | McMahon | Jul 2006 | A1 |
20060164291 | Gunnarsson | Jul 2006 | A1 |
20060198463 | Godin | Sep 2006 | A1 |
20060220990 | Coushaine et al. | Oct 2006 | A1 |
20060227085 | Boldt, Jr. et al. | Oct 2006 | A1 |
20070040512 | Jungwirth et al. | Feb 2007 | A1 |
20070109239 | den Boer et al. | May 2007 | A1 |
20070132592 | Stewart et al. | Jun 2007 | A1 |
20070139957 | Haim et al. | Jun 2007 | A1 |
20070248180 | Bowman et al. | Oct 2007 | A1 |
20070254694 | Nakagwa et al. | Nov 2007 | A1 |
20070279346 | den Boer et al. | Dec 2007 | A1 |
20070284994 | Morimoto et al. | Dec 2007 | A1 |
20080061717 | Bogner et al. | Mar 2008 | A1 |
20080107029 | Hall et al. | May 2008 | A1 |
20080120559 | Yee | May 2008 | A1 |
20080136334 | Robinson et al. | Jun 2008 | A1 |
20080136770 | Peker et al. | Jun 2008 | A1 |
20080136771 | Chen et al. | Jun 2008 | A1 |
20080150864 | Bergquist | Jun 2008 | A1 |
20080186898 | Petite | Aug 2008 | A1 |
20080222367 | Co | Sep 2008 | A1 |
20080235418 | Werthen et al. | Sep 2008 | A1 |
20080253766 | Yu et al. | Oct 2008 | A1 |
20080265799 | Sibert | Oct 2008 | A1 |
20080297070 | Kuenzler et al. | Dec 2008 | A1 |
20080304833 | Zheng | Dec 2008 | A1 |
20080309255 | Myers et al. | Dec 2008 | A1 |
20080317475 | Pederson et al. | Dec 2008 | A1 |
20090016390 | Sumiyama et al. | Jan 2009 | A1 |
20090026978 | Robinson | Jan 2009 | A1 |
20090040154 | Scheibe | Feb 2009 | A1 |
20090049295 | Erickson et al. | Feb 2009 | A1 |
20090051496 | Pahlavan et al. | Feb 2009 | A1 |
20090121238 | Peck | May 2009 | A1 |
20090171571 | Son et al. | Jul 2009 | A1 |
20090196282 | Fellman et al. | Aug 2009 | A1 |
20090245101 | Kwon et al. | Oct 2009 | A1 |
20090278789 | Declercq et al. | Nov 2009 | A1 |
20090284511 | Takasugi et al. | Nov 2009 | A1 |
20090303972 | Flammer, III et al. | Dec 2009 | A1 |
20100005533 | Shamir | Jan 2010 | A1 |
20100020264 | Ohkawa | Jan 2010 | A1 |
20100054748 | Sato | Mar 2010 | A1 |
20100061734 | Knapp | Mar 2010 | A1 |
20100096447 | Kwon et al. | Apr 2010 | A1 |
20100134021 | Ayres | Jun 2010 | A1 |
20100134024 | Brandes | Jun 2010 | A1 |
20100141159 | Shiu et al. | Jun 2010 | A1 |
20100182294 | Roshan et al. | Jul 2010 | A1 |
20100188443 | Lewis et al. | Jul 2010 | A1 |
20100188972 | Knapp | Jul 2010 | A1 |
20100194299 | Ye et al. | Aug 2010 | A1 |
20100213856 | Mizusako | Aug 2010 | A1 |
20100272437 | Yoon et al. | Oct 2010 | A1 |
20100301777 | Kraemer | Dec 2010 | A1 |
20100327764 | Knapp | Dec 2010 | A1 |
20110031894 | Van De Ven | Feb 2011 | A1 |
20110044343 | Sethuram et al. | Feb 2011 | A1 |
20110052214 | Shimada et al. | Mar 2011 | A1 |
20110062874 | Knapp | Mar 2011 | A1 |
20110063214 | Knapp | Mar 2011 | A1 |
20110063268 | Knapp | Mar 2011 | A1 |
20110068699 | Knapp | Mar 2011 | A1 |
20110069094 | Knapp | Mar 2011 | A1 |
20110069960 | Knapp et al. | Mar 2011 | A1 |
20110084701 | Bancken et al. | Apr 2011 | A1 |
20110133654 | McKenzie et al. | Jun 2011 | A1 |
20110148315 | Van Der Veen et al. | Jun 2011 | A1 |
20110150028 | Nguyen et al. | Jun 2011 | A1 |
20110187281 | Lu | Aug 2011 | A1 |
20110241572 | Zhang et al. | Oct 2011 | A1 |
20110248640 | Welten | Oct 2011 | A1 |
20110253915 | Knapp | Oct 2011 | A1 |
20110299854 | Jonsson et al. | Dec 2011 | A1 |
20110309754 | Ashdown et al. | Dec 2011 | A1 |
20120001570 | Deurenberg et al. | Jan 2012 | A1 |
20120056545 | Radermacher et al. | Mar 2012 | A1 |
20120153839 | Farley et al. | Jun 2012 | A1 |
20120229032 | Van De Ven et al. | Sep 2012 | A1 |
20120286694 | Elder | Nov 2012 | A1 |
20120299481 | Stevens | Nov 2012 | A1 |
20120306370 | Van De Ven et al. | Dec 2012 | A1 |
20130009551 | Knapp | Jan 2013 | A1 |
20130016978 | Son et al. | Jan 2013 | A1 |
20130088522 | Gettemy et al. | Apr 2013 | A1 |
20130201690 | Vissenberg et al. | Aug 2013 | A1 |
20130257314 | Alvord et al. | Oct 2013 | A1 |
20130293147 | Rogers et al. | Nov 2013 | A1 |
20130393147 | Rogers et al. | Nov 2013 | |
20140028377 | Rosik et al. | Jan 2014 | A1 |
20140225529 | Beczkowski | Aug 2014 | A1 |
20140333202 | Hechtfischer | Nov 2014 | A1 |
20150022110 | Sisto | Jan 2015 | A1 |
20150055960 | Zheng et al. | Feb 2015 | A1 |
20150155459 | Ishihara et al. | Jun 2015 | A1 |
20150312990 | van de Ven et al. | Oct 2015 | A1 |
20150351187 | McBryde | Dec 2015 | A1 |
20150377695 | Chang et al. | Dec 2015 | A1 |
20150382425 | Lewis et al. | Dec 2015 | A1 |
20170105260 | Ho et al. | Apr 2017 | A1 |
20180084617 | Zhang et al. | Mar 2018 | A1 |
20180160491 | Biery et al. | Jun 2018 | A1 |
Number | Date | Country |
---|---|---|
1291282 | Apr 2001 | CN |
1396616 | Feb 2003 | CN |
1573881 | Feb 2005 | CN |
1596054 | Mar 2005 | CN |
1650673 | Aug 2005 | CN |
1830096 | Sep 2006 | CN |
1849707 | Oct 2006 | CN |
101083866 | Dec 2007 | CN |
101150904 | Mar 2008 | CN |
101331798 | Dec 2008 | CN |
101458067 | Jun 2009 | CN |
101772988 | Jul 2010 | CN |
102422711 | Apr 2012 | CN |
102573214 | Jul 2012 | CN |
102625944 | Aug 2012 | CN |
102695332 | Sep 2012 | CN |
103718005 | Apr 2014 | CN |
102007036978 | Feb 2009 | DE |
0196347 | Oct 1986 | EP |
0456462 | Nov 1991 | EP |
0677983 | Oct 1995 | EP |
1482770 | Dec 2004 | EP |
2273851 | Jan 2011 | EP |
2307577 | May 1997 | GB |
06-302384 | Oct 1994 | JP |
08-201472 | Aug 1996 | JP |
11-025822 | Jan 1999 | JP |
2001-514432 | Sep 2001 | JP |
2004-325643 | Nov 2004 | JP |
2005-539247 | Dec 2005 | JP |
2006-260927 | Sep 2006 | JP |
2007-266974 | Oct 2007 | JP |
2007-267037 | Oct 2007 | JP |
2008-507150 | Mar 2008 | JP |
2008-300152 | Dec 2008 | JP |
2009-134877 | Jun 2009 | JP |
0037904 | Jun 2000 | WO |
03075617 | Sep 2003 | WO |
2005024898 | Mar 2005 | WO |
2007004108 | Jan 2007 | WO |
2007069149 | Jun 2007 | WO |
2008065607 | Jun 2008 | WO |
2008129453 | Oct 2008 | WO |
2010124315 | Nov 2010 | WO |
2011016860 | Feb 2011 | WO |
2012005771 | Jan 2012 | WO |
2012042429 | Apr 2012 | WO |
2013041109 | Mar 2013 | WO |
2013142437 | Sep 2013 | WO |
Entry |
---|
International Search Report & Written Opinion, PCT/US2010/000219, dated Oct. 12, 2010. |
International Search Report & Written Opinion, PCT/US2010/002171, dated Nov. 24, 2010. |
International Search Report & Written Opinion, PCT/US2010/004953, dated Mar. 22, 2010. |
International Search Report & Written Opinion, PCT/US2010/001919, dated Feb. 24, 2011. |
Office Action dated May 12, 2011 for U.S. Appl. No. 12/360,467. |
Final Office Action dated Nov. 28, 2011 for U.S. Appl. No. 12/360,467. |
Notice of Allowance dated Jan. 20, 2012 for U.S. Appl. No. 12/360,467. |
Office Action dated Feb. 1, 2012 for U.S. Appl. No. 12/584,143. |
Final Office Action dated Sep. 12, 2012 for U.S. Appl. No. 12/584,143. |
Office Action dated Aug. 2, 2012 for U.S. Appl. No. 12/806,114. |
Office Action dated Oct. 2, 2012 for U.S. Appl. No. 12/806,117. |
Office Action dated Jul. 11, 2012 for U.S. Appl. No. 12/806,121. |
Final Office Action dated Oct. 11, 2012 for U.S. Appl. No. 12/806,121. |
Office Action dated Dec. 17, 2012 for U.S. Appl. No. 12/806,118. |
Office Action dated Oct. 9, 2012 for U.S. Appl. No. 12/806,126. |
Office Action dated Jul. 10, 2012 for U.S. Appl. No. 12/806,113. |
Notice of Allowance dated Oct. 15, 2012 for U.S. Appl. No. 12/806,113. |
International Search Report & Written Opinion dated Sep. 19, 2012 for PCT/US2012/045392. |
Partial International Search Report dated Nov. 16, 2012 for PCT/US2012/052774. |
Office Action dated Nov. 4, 2013 for CN Application No. 201080032373.7. |
Office Action dated Dec. 4, 2013 for U.S. Appl. No. 12/803,805. |
Notice of Allowance dated Jan. 28, 2014 for U.S. Appl. No. 13/178,686. |
Notice of Allowance dated Feb. 21, 2014 for U.S. Appl. No. 12/806,118. |
Office Action dated Apr. 22, 2014 for U.S. Appl. No. 12/806,114. |
International Search Report & Written Opinion for PCT/US2012/052774 dated Feb. 4, 2013. |
Notice of Allowance dated Feb. 4, 2013 for U.S. Appl. No. 12/809,113. |
Notice of Allowance dated Feb. 25, 2013 for U.S. Appl. No. 12/806,121. |
Notice of Allowance dated May 3, 2013 for U.S. Appl. No. 12/806,126. |
International Search Report & Written Opinion, PCT/US2013/027157, dated May 16, 2013. |
Office Action dated Jun. 10, 2013 for U.S. Appl. No. 12/924,628. |
Office Action dated Jun. 27, 2013 for U.S. Appl. No. 13/178,686. |
Final Office Action dated Jul. 9, 2013 for U.S. Appl. No. 12/806,118. |
Final Office Action dated Jun. 14, 2013 for U.S. Appl. No. 12/806,117. |
Johnson, “Visibile Light Communications,” CTC Tech Brief, Nov. 2009, 2 pages. |
Chonko, “Use Forward Voltage Drop to Measure Junction Temperature,” © 2013 Penton Media, Inc., 5 pages. |
Office Action dated Oct. 24, 2013 for U.S. Appl. No. 12/806,117. |
Notice of Allowance dated Oct. 31, 2013 for U.S. Appl. No. 12/924,628. |
Office Action dated Nov. 12, 2013 for U.S. Appl. No. 13/231,077. |
Final Office Action dated Jun. 18, 2014 for US Appl. No. 13/231,077. |
Office Action dated Jun. 23, 2014 for U.S. Appl. No. 12/806,117. |
Notice of Allowance dated Aug. 21, 2014 for U.S. Appl. No. 12/584,143. |
Office Action dated Sep. 10, 2014 for U.S. Appl. No. 12/803,805. |
Office Action dated Jan. 28, 2015 for U.S. Appl. No. 12/806,117. |
Office Action dated Feb. 2, 2015 for CN Application 201080035731. |
Office Action dated Jul. 1, 2014 for JP Application 2012-520587. |
Office Action dated Feb. 17, 2015 for JP Application 2012-520587. |
Office Action dated Mar. 11, 2014 for JP Application 2012-523605. |
Office Action dated Sep. 24, 2014 for JP Application 2012-523605. |
Office Action dated Mar. 25, 2015 for U.S. Appl. No. 14/305,472. |
Notice of Allowance dated Mar. 30, 2015 for U.S. Appl. No. 14/097,355. |
Office Action dated Apr. 8, 2015 for U.S. Appl. No. 14/305,456. |
Notice of Allowance dated May 22, 2015 for U.S. Appl. No. 14/510,212. |
Office Action dated May 27, 2015 for U.S. Appl. No. 12/806,117. |
Partial International Search Report dated Mar. 27, 2015 for PCT/US2014/068556. |
International Search Report & Written Opinion for PCT/US2014/068556 dated Jun. 22, 2015. |
Final Office Action for U.S. Appl. No. 12/803,805 dated Jun. 23, 2015. |
Office Action for U.S. Appl. No. 13/970,964 dated Jun. 29, 2015. |
Office Action for U.S. Appl. No. 14/510,243 dated Jul. 28, 2015. |
Office Action for U.S. Appl. No. 13/970,990 dated Aug. 20, 2015. |
Partial International Search Report for PCT/US2015/037660 dated Aug. 21, 2015. |
Final Office Action for U.S. Appl. No. 13/773,322 dated Sep. 2, 2015. |
Notice of Allowance for U.S. Appl. No. 13/970,944 dated Sep. 11, 2015. |
Notice of Allowance for U.S. Appl. No. 14/604,886 dated Sep. 25, 2015. |
Notice of Allowance for U.S. Appl. No. 14/604,881 dated Oct. 9, 2015. |
International Search Report & Written Opinion for PCT/US2015/037660 dated Oct. 28, 2015. |
Office Action for U.S. Appl. No. 14/573,207 dated Nov. 4, 2015. |
Notice of Allowance for U.S. Appl. No. 14/510,243 dated Nov. 6, 2015. |
Notice of Allowance for U.S. Appl. No. 12/806,117 dated Nov. 18, 2015. |
Partial International Search Report for PCT/US2015/045252 dated Nov. 18, 2015. |
Office Action dated Mar. 6, 2015 for U.S. Appl. No. 13/733,322. |
International Search Report and the Written Opinion for PCT/US2015/035081 dated Jan. 26, 2016. |
Office Action for U.S. Appl. No. 14/510,283 dated Jul. 29, 2015. |
Reissue U.S. Appl. No. 16/282,231, filed Feb. 21, 2019. |
Reissue U.S. Appl. No. 16/033,917, filed Jul. 12, 2018. |
Reissue U.S. Appl. No. 16/205,071, filed Nov. 29, 2018. |
Reissue U.S. Appl. No. 15/970,436, filed May 3, 2018. |
International Search Report and the Written Opinion for PCT/US2015/045252 dated Jan. 26, 2016. |
U.S. Appl. No. 16/819,497, filed Mar. 16, 2020. |
“Office Action for U.S. Appl. No. 14/510,266 dated Jul. 31, 2015”,10 pages. |
“Search Report, Chinese Patent Application CN 2018112133483 A, dated Mar. 24, 2021”. |
Hall et al., “Jet Engine Control Using Ethernet with a BRAIN (Postprint),” AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibition, Jul. 2008, pp. 1-18. |
Kebemou, “A Partitioning-Centric Approach for the Modeling and the Methodical Design of Automotive Embedded System Architectures,” Dissertation of Technical University of Berlin, 2008, 176 pages. |
O'Brien et al., “Visible Light Communications and Other Developments in Optical Wireless,” Wireless World Research Forum, 2006, 26 pages. |
Zalewski et al., “Safety Issues in Avionics and Automotive Databuses,” IFAC World Congress, Jul. 2005, 6 pages. |
“Visible Light Communication: Tutorial,” Project IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs), Mar. 2008. |
Johnson, “Visible Light Communications,” CTC Tech Brief, Nov. 2009, 2 pages. |
Office Action mailed Oct. 24, 2013 for U.S. Appl. No. 12/806,117. |
“Color Management of a Red, Green, and Blue LED Combinational Light Source,” Avago Technologies, Mar. 2010, pp. 1-8. |
Final Office Action mailed Jan. 28, 2015 for U.S. Appl. No. 12/806,117. |
Office Action mailed Feb. 2, 2015 for CN Application 201080035731.X. |
Bouchet et al., “Visible-light communication system enabling 73 Mb/s data streaming,” IEEE Globecom Workshop on Optical Wireless Communications, 2010, pp. 1042-1046. |
“LED Fundamentals, How to Read a Datasheet (Part 2 of 2) Characteristic Curves, Dimensions and Packaging,” Aug. 19, 2011, OSRAM Opto Semiconductors, 17 pages. |
Office Action for U.S. Appl. No. 14/510,283 mailed Jul. 29, 2015. |
Number | Date | Country | |
---|---|---|---|
Parent | 14314530 | Jun 2014 | US |
Child | 14510266 | US | |
Parent | 14097339 | Dec 2013 | US |
Child | 14314530 | US | |
Parent | 13970990 | Aug 2013 | US |
Child | 14097339 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 14510266 | Oct 2014 | US |
Child | 15982681 | US |