Patent Application
20080062706
Different aspects of the various embodiments of the present invention will become apparent from the following specification, drawings and claims in which:
a shows a block diagram of one embodiment of automotive LED illumination system 100;
b shows further illustrative details of one embodiment of LED light source and optical system 400 of the present invention that may be employed in system 100 of
a through 2i illustrate different embodiments of some LED light source and optical systems 400 of the present invention;
a shows light wavelength spectra corresponding to some LEDs that may be employed in the present invention;
b shows a CIE chromaticity diagram;
a shows standard power spectral distributions corresponding to blue, green and red LEDs, and a power spectral distribution resulting from the combination of the light emitted by such LEDs;
b shows power spectral distributions corresponding to different brightness levels in accordance with one embodiment of the present invention;
c shows power spectral distributions corresponding to different colors in accordance with another embodiment of the present invention;
d shows power spectral distributions corresponding to different brightness levels and colors in accordance with yet another embodiment of the present invention;
a through 5f illustrate various types of outputs that may be achieved using LED brightness control circuit 310 and LED drive circuit 325 of the present invention;
a through 6e illustrate various types of outputs that may be achieved using LED color control circuit 315 and LED drive circuit 325 of the present invention;
a illustrates one embodiment of a method of controlling and modulating light emitted by an automotive illumination system 100 of the present invention, and
b illustrates another embodiment of a method of controlling and modulating light emitted by an automotive illumination system 100 of the present invention.
The drawings are not necessarily to scale. Like numbers refer to like parts or steps throughout the drawings.
In the specification, claims and drawings attached hereto, the following terms have the following meanings:
The term “brightness” means the relative intensity or amplitude of the energy output of light source visible to a human observer, or in the case of some infra-red wavelengths, capable of being detected by an appropriate sensor.
The term “color” means the color of light falling within the spectrum of light visible to a normative human observer and capable of being perceived thereby; different colors are defined by their respective wavelengths and chromaticity as shown in
The term “LED light source” includes within its scope a light source comprising a plurality of LEDs and/or a plurality of clusters or groups of LEDs.
Set forth below are detailed descriptions of some preferred embodiments of the systems, devices, components and methods of the present invention.
a shows a block diagram of one embodiment of automotive LED illumination system 100, comprising LED illumination control and sensor system 200 and LED light source and optical system 400. LED illumination control and sensor system 200 further comprises LED control and drive circuit 300, environmental sensors 205 providing inputs 1 through n to A/D converter 330, user/manufacturer input/control 210, and software download/update input 215. Light sensors 220 provide inputs 1 through m to A/D converter 330. LED drive and control circuit 300 comprises A/D converter 330, LED control circuit 305 for controlling LEDs 1 through k, and LED drive circuit 325 for driving LEDs in LED light source 500.
LED light source and optical system 400 comprises LED light source 500 and optical assembly 600. LED light source 500 includes LED light source modules or lamp units 515, which contain individual LEDs 505 or clusters or groups of LEDs 510 (not shown individually in
Note that automotive illumination system 100 of the present invention may be employed in one or more of automotive headlights, automotive daytime modulators, automotive turn signals, automotive tail lights, automotive brake lights, automotive running lights, automotive fog lights, automotive backup lights, automotive cabin lights, and other automotive illumination applications.
In one embodiment of the present invention, LED control and drive circuit 300 does not include A/D converter 330 or inputs from environmental sensors 205 and light sensors 220. In such an embodiment, LED control and drive circuit 300 operates to controllably configure the brightness, color, and/or color and brightness of light emitted by LED light source 500 without sensing the output of LED light source 500 or of environmental sensors 205, and without using same as feedback control mechanisms for LED control circuit 305.
In another embodiment of the present invention, LED control and drive circuit 300 includes AND converter 330 and inputs from either or both of environmental sensors 205 and light sensors 220. In such an embodiment, LED control and drive circuit 300 operates to controllably configure the brightness, color, and/or color and brightness of light emitted by LED light source 500 using output signals provided by either or both of source 500 and environmental sensors 205 as feedback control mechanisms for LED control circuit 305.
User/manufacturer input/control 210 and software download/update input 215 are both optional features of the present invention. User/manufacturer input/control 210 may be employed by either a manufacturer of system 100 or by a user of system 100 to controllably configure LED drive control circuit and the resulting spatial, time, or space and time control over the brightness, color, and/or brightness and color of light emitted by LED light source 500. Predetermined patterns or configurations of light emitted by LED light sources 500 may be selected by the manufacturer or user, or such predetermined patterns or configurations may be adjusted by the user or manufacturer. Software download/update input 215 may be used by a manufacturer or technician to load updated or new brightness, color, and/or brightness and color control software into LED control circuit 305.
Continuing to refer to
In another embodiment of the present invention, and continuing to refer to
In yet another embodiment of the present invention, and continuing to refer to
Any one or more of A/D converter 330, LED control circuit 305 and LED drive circuit 325 may be incorporated into a controller, a micro-controller, a processor, a micro-processor, a processing unit, a CPU, an ASIC, an integrated circuit or a chip.
In respect of LED illumination control and sensor system 200 of the present invention, particular reference is made to the following U.S. Patents assigned to Avago Technologies ECBU IP (Singapore) Pte., Ltd. for detailed information concerning the control and driving, and feedback control, of light emitted by LED light sources: (1) U.S. Pat. No. 6,344,641 to Blalock et al. for “System and method for on-chip calibration of illumination sources for an integrated display,” Feb. 5, 2002; (2) U.S. Pat. No. 6,448,550 to Nishimura for “Method and apparatus for measuring spectral content of LED light source and control thereof,” Sep. 10, 2002; (3) U.S. Pat. No. 6,894,442 to Lim et al. for “Luminary control system,” May 17, 2005; (4) U.S. Pat. No. 7,009,343 to Lim et al. for “System and method for producing white light using LEDs,” Mar. 7, 2006, and (5) U.S. Patent Publication No. 20060054776 to Nishimura for “Method and apparatus for regulating the drive currents of a plurality of light emitters,” Mar. 16, 2006. Each of the foregoing publications is hereby incorporated by reference herein, each in its respective entirety.
The capabilities of the various embodiments of the present invention may be employed to custom-configure the appearance and function of light emitted by LED light source and optical system 400, depending on the particular circumstances under which system 100 is being used. For example, in a case where LED light source and optical system 400 is a headlight or tail light comprising an array of LEDs 535, LED light source 500 may be controllably configured to accent or follow design cues of the automobile in which system 100 has been installed by varying the brightness, the color, or both the brightness and the color of the various LEDs 505 in LED array 535 in accordance with such design cues. The brightness, hue, tint or color of light emitted by system 100 may also be configured to complement or match the paint color of the automobile in which system 100 has been installed.
As external lighting conditions change at dawn, during the day, at dusk or at night, the brightness, hue, tint or color of light emitted by system 100 may be configured using inputs from environmental sensors 205 to provide customized optimal lighting according to the ambient light conditions in existence at the moment, or may be adjusted to complement or match the paint color or physical appearance of the automobile in which system 100 has been installed. System 100 of the present invention may be configured to sense and respond to changing weather or external light conditions and provide emitted light that is tuned or optimized to the particular ambient conditions at hand. As a further example, in response to foggy conditions being detected by environmental sensors 205, system 100 may be adjusted to provide light emitted from headlights that is more yellowish in tint than conventional “white” light. Many other possibilities for changing the brightness, color, or brightness and color of light emitted by system 100 are possible, more about which is said below.
Environmental sensor 205 is configured to sense at least one environmental characteristic and provide one or more inputs based on same to A/D converter 330. As discussed above, such inputs may be employed as part of a feedback control system for controlling and adjusting the brightness, color and/or brightness and color of light emitted by LED light source 500. Environmental sensor 205 may be any one or more of an external lighting level sensor, an automotive cabin lighting level sensor, on-coming headlight sensor, a rain sensor, a water sensor, a mist sensor, a snow sensor, an ice sensor, a sleet sensor, a fog sensor, a road width sensor, a road condition sensor, a road type sensor, an accelerometer, an automotive speed sensor, a pedestrian sensor, an off-axis vehicle sensor, a moving object sensor, an ignition key sensor, a keyless entry remote control sensor, a door sensor, a trunk sensor, an alarm sensor, a proximity sensor, a seatbelt sensor, an accident sensor, and/or any other type of suitable sensor. Multiple input signals of different types may be provided to A/D converter 330 by environmental sensors 205.
Light sensors 220 of the present invention may be photosensors, photodiodes, photodetectors, or any other suitable type of light sensor capable of sensing the brightness and/or color of light emitted by system 100. Light sensors 220 may be positioned in any of a number of different locations within or outside LED light source and optical system 400. For example, in one embodiment of the present invention, light sensors 220 may be disposed on an LED chip or semiconductor 525 between LEDs 505 in a manner similar to that described in the '550 patent to Nishimura. Light sensors 220 may be located anywhere within system 400 or external thereto, so long as sensors 220 are capable of effectively sensing the brightness or color of light emitted by system 100.
In a preferred embodiment of the present invention, LED light source 500 comprises one or more LED chips or semiconductors 525 such as those described in the foregoing '641, '550, '442 and '343 patents assigned to Avago Technologies. In such embodiments, light source 500 may further comprise fluorescent material disposed adjacent one or more of the LEDs thereof, which material will radiate light in response to having been excited by light emitted from adjacent LEDs. LED light source 500 is not limited to semiconductor embodiments, however, and includes within its scope printed circuit boards containing discrete LEDs mounted thereon, as well as other types of LED light sources presently known in the automotive lighting arts. LED light source 500 may also be attached to, mounted on or form a portion of LED support 540, as shown in
Referring now to
As is described in further detail below in connection with
a through 2i illustrate various different embodiment of some of the LED light source and optical systems 400 of the present invention. As will become apparent by referring to the embodiments of the present invention illustrated in
a shows one system 400 where LED light source 500 comprises individual LEDs 505 mounted on LED support 540. Light rays 625 emitted by LEDs 505 are reflected by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620.
b shows another system 400 where LED light source 500 comprises LED chip 525 mounted on LED support 540. Light rays 625 emitted by LED chip 525 are reflected by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED chip 525 and LED support 540, which is mounted on LED housing 520. As shown in
c shows a system 400 where LED light source 500 comprises LED chip 525 mounted on LED support 540. Light rays 625 emitted by LED chip 525 are reflected by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED chip 525 and LED support 540.
d shows another system 400 where LED light source 500 comprises LED chip 525 mounted on LED support 540, which in turn is attached to LED housing 520. Portions of light rays 625 emitted by LED chip 525 are blocked by shade 615, which forms a portion of LED housing 520. Light rays 625 not blocked by shade 615 are directed through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620.
e shows one system 400 similar to that illustrated in
f shows a system 400 where LED light source 500 again comprises LED chip 525 mounted on LED support 540. Light rays 625 emitted by LED chip 525 are reflected by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED chip 525 and LED support 540, which is mounted on LED housing 520/reflector 605. As shown in
g shows another system 400 where LED light source 500 comprises LED chip 525 mounted on LED support 540 and LED housing 520. Light rays 625 emitted by LED chip 525 are reflected by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED chip 525, LED support 540 and LED housing 520.
h shows one system 400 where LED light source 500 comprises LED 505 mounted on LED support 540. Light rays 625 emitted backwardly from LED 505 are reflected forwardly by reflector 605 through lens 610 to form collimated light beams 630 which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED support 540 and LED housing 520.
i shows another system 400 where LED light source 500 comprises LED chip 525 mounted on LED support 540. Light rays 625 emitted by LED chip 525 are captured by surrounding LED lens or translucent member 550 and collimated forwardly to create collimated light beams 630, which are directed approximately along optical axis 620. LED light source or lamp unit 515 comprises LEDs 505, LED chip 525, LED support 540, and LED housing 520. Note that no reflector 605 is necessarily required in the embodiment of the present invention illustrated in
In some embodiments of the present invention, the use of LEDs capable of emitting light of different colors is contemplated. Table 1 below lists some of the more commonly available colors of LEDs which may be employed in the present invention.
Light emitted by LEDs of different color, and their corresponding individual intensities or brightnesses, may be modulated by means of LED control circuit 305, LED drive circuit 325 and/or optical system 400 to produce collimated light beams 635 having many, if not most, of the colors illustrated in the CIE chromaticity diagram of
In a preferred embodiment of the present invention, light source 500 comprises one or more clusters of LEDs having three different colors, such as red, green and blue, to permit finer modulation and better control of the combined colors emitted by LED clusters 510 comprising three LEDs. More than three LEDs may also be employed in LED clusters or groups 510 of the present invention, depending on the particular application at hand. For example, if a single LED 505 of a first color emits less light relative to an LED 505 of a second or third color, more than one LED 505 of the first color may be employed in a cluster of LEDs 510 comprising LEDs 505 of the first, second and third colors. Or an LED 505 of a fourth color may be added to an LED cluster 510 comprising LEDs 505 of first, second and third colors to fill in a gap in, or low-amplitude portion of, the combined light spectrum emitted by the LEDs 505 of the first, second and third colors.
Referring now to
b shows PSD 700 labeled as a “First Brightness Level,” and two other curves labeled 705 (“Second Brightness Level”) and 710 (“Third Brightness Level”). The three brightness levels of
Reference to
c shows PSD 700 labeled as a “First Color PSD,” and two other curves labeled 715 (“Second Color PSD”) and 720 (“Third Color PSD”). The three PSDs shown in
Reference to
d shows PSD 700 labeled as a “First Color and Brightness Level,” and two other curves labeled 725 (“Second Color and Brightness Level”) and 730 (“Third Color and Brightness Level”). The three color and brightness levels of
a through 5f illustrate various types of outputs that may be achieved using is LED brightness control circuit 310 and LED drive circuit 325 of the present invention. For purposes of clarity, note that components of optical system 600 such as reflectors 605, lenses 610 or other optical elements 615 are not shown in
a shows one embodiment of a brightness-controllable automotive illumination device of the present invention. In
b and 5c illustrate the operation of one embodiment of a headlight of the present invention.
When the headlight of system 100 is in the first state shown in
When the headlight of system 100 is in the second state shown in
Referring now to
Referring now to
a through 6e illustrate various types of outputs that may be achieved using LED color control circuit 315 and LED drive circuit 325 of the present invention.
For purposes of clarity, note that components of optical system 600 such as reflectors 605, lenses 610 or other optical elements 615 are not shown in
a shows one embodiment of a color-controllable automotive illumination device of the present invention. In
b shows another embodiment of a color-controllable automotive illumination device of the present invention. In a first state, color triads 510 in rows a through c are brightness- and color-modulated to operate as a high beam headlight. In a second state, color triads 510 in rows a through c are brightness- and color-modulated to operate as a low beam headlight, or a low-beam headlight and a fog light. Alternatively, in a first state color triads 510 in rows a through c are brightness- and color-modulated to operate as a headlight, and in a second state, color triads 510 in rows a and b are brightness- and color-modulated to operate as a headlight, and color triads 510 in row c are brightness- and color-modulated to operate as a turn signal or running light. As will now become apparent, many other combinations of color-controllable headlights, daytime modulators, turn signals, tail lights, brake lights, running lights, fog lights and backup lights may also be employed in the present invention.
d shows another embodiment of a color-controllable automotive illumination device of the present invention. LEDs/LED clusters 505/510 located at the intersections of rows a though e and columns A through G are preferably color triads 510. As illustrated in
The various brightness and color patterns and concepts illustrated in
a illustrates one embodiment of a method of controlling and modulating light emitted by an automotive illumination system 100 of the present invention. Environmental sensors 205 provide input signals to LED control circuit 305, which are then employed to adjust the light emitted by LED light source and optical system 400. In the example of
b illustrates another embodiment of a method of controlling and modulating light emitted by an automotive illumination system 100 of the present invention. A user selects between predetermined brightness, color, and/or color and brightness patterns that are to be employed in system 100 of the present invention.
Other embodiments of the present invention include an integrated circuit for an automotive illumination system, comprising an LED brightness control circuit configured to control the brightness of light emitted by LED light sources between at least one minimum brightness level and at least one maximum brightness level, where the at least one minimum brightness level may be configured to be greater than zero. The integrated circuit may further comprise at least one signal input means corresponding to the output of a light sensor, the integrated circuit, the at least one signal input means and the light sensor output comprising a feedback control system for controlling and adjusting the brightness of light emitted by the LED light sources. The at least one signal input may be provided by an analog-to-digital converter forming a portion of the integrated circuit. The integrated circuit may further comprise an LED drive circuit for driving LED light sources.
The present invention includes within its scope various methods of controlling the brightness, the color, and the brightness and the color of light emitted by an automotive illumination system, methods of adjusting the brightness, color and brightness and color of light emitted by an automotive feedback control illumination system, methods of making automotive illumination systems, methods of making automotive feedback control illumination systems, methods of installing automotive illumination systems, methods of installing automotive feedback control illumination systems, and methods of making automobiles.
The preceding specific embodiments are illustrative of the practice of the invention. It is to be understood, therefore, that other expedients known to those skilled in the art or disclosed herein may be employed without departing from the invention or the scope of the appended claims. For example, the present invention is not strictly limited to automotive illumination systems, devices, components and methods, but may also be employed in trucks, buses, and other forms of transportation.
Having read and understood the present disclosure, those skilled in the art will now understand that many combinations, adaptations, variations and permutations of known automotive illumination systems, devices, components and methods may be employed successfully in the present invention.
In the claims, means plus function clauses are intended to cover the structures described herein as performing the recited function and their equivalents. Means plus function clauses in the claims are not intended to be limited to structural equivalents only, but are also intended to include structures which function equivalently in the environment of the claimed combination.
All printed publications and patents referenced hereinabove are hereby incorporated by referenced herein, each in its respective entirety.
