1. Field
The present disclosure pertains to systems and methods for controlling current being supplied to light sources, and, in particular, to systems and methods that control and/or provide a panel of light emitting diodes that is suitable to treat jaundice in infants by maintaining irradiance at a level corresponding to a recommended level.
2. Description of the Related Art
Infants, e.g. neonates, may be treated with phototherapy. An example of phototherapy is jaundice treatment using a panel of light sources that emit, e.g., blue light.
Accordingly, it is an object of one or more embodiments of the present invention to provide a system. The system includes a set of light sources, a photo-sensor, and one or more processors. The set of light sources is configured to emit electromagnetic radiation. The set includes light-emitting diodes. The photo-sensor is configured to generate output signals conveying information related to an irradiance level of electromagnetic radiation emitted by a subset of light sources from the set of light sources. The one or more processors are configured to obtain a recommended therapy regimen of electromagnetic radiation for a subject, to determine an irradiance parameter of electromagnetic radiation emitted by the subset of light sources, wherein the irradiance parameter is based on the generated output signals, and to adjust an amount of power supplied to the set of light sources. The adjustments are based on the recommended therapy regimen and the determined irradiance parameter
It is yet another aspect of one or more embodiments of the present invention to provide a method of adjusting an amount of power supplied to a set of light sources. The method includes activating a set of light sources, wherein the set includes light-emitting diodes (LEDs); emitting, by the set of light sources, electromagnetic radiation responsive to activation; generating output signals conveying information related to an irradiance level of electromagnetic radiation emitted by a subset of light sources from the set of light sources; obtaining a recommended therapy regimen of electromagnetic radiation for a subject; determining an irradiance parameter of electromagnetic radiation emitted by the subset of light sources, wherein the irradiance parameter is based on the output signals; and adjusting an amount of power supplied to the set of light sources, wherein adjustments are based on the recommended therapy regimen and the determined irradiance parameter.
It is yet another aspect of one or more embodiments to provide a system configured to adjust an amount of power supplied to a set of light source. The system includes emitting means for emitting electromagnetic radiation, wherein the emitting means includes light-emitting diodes (LEDs); means for generating output signals conveying information related to an irradiance level of electromagnetic radiation emitted by a portion of the emitting means; means for obtaining a recommended therapy regimen of electromagnetic radiation for a subject; means for determining an irradiance parameter of electromagnetic radiation emitted by the portion of the emitting means, wherein the irradiance parameter is based on the output signals; and means for adjusting an amount of power supplied to the means for emitting, wherein adjustments are based on the recommended therapy regimen and the determined irradiance parameter.
These and other objects, features, and characteristics of the present invention, as well as the methods of operation and functions of the related elements of structure and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention.
As used herein, the singular form of “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. As used herein, the statement that two or more parts or components are “coupled” shall mean that the parts are joined or operate together either directly or indirectly, i.e., through one or more intermediate parts or components, so long as a link occurs. As used herein, “directly coupled” means that two elements are directly in contact with each other. As used herein, “fixedly coupled” or “fixed” means that two components are coupled so as to move as one while maintaining a constant orientation relative to each other.
As used herein, the word “unitary” means a component is created as a single piece or unit. That is, a component that includes pieces that are created separately and then coupled together as a unit is not a “unitary” component or body. As employed herein, the statement that two or more parts or components “engage” one another shall mean that the parts exert a force against one another either directly or through one or more intermediate parts or components. As employed herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality).
Directional phrases used herein, such as, for example and without limitation, top, bottom, left, right, upper, lower, front, back, and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein.
Phototherapy can be used to treat jaundice (or hyperbilirubinemia) by reducing the level of bilirubin. Effective and/or appropriate levels of phototherapy may be based on an infant's age, size, weight, and/or other physiological, environmental, and/or infant-specific parameters. Phototherapy uses electromagnetic radiation having a peak wavelength between, e.g., 460 nm and 500 nm, an emission spectrum ranging from, e.g., 400 nm to 520 nm, and preferably using a narrow bandwidth delivered at an irradiance of, e.g., 15-35·W/cm2/nm to, e.g., up to 80% of an infant's body surface area (BSA). Phototherapy may potentially need to be kept from directly impinging on the eyes of the infant, e.g. by making the infant wear goggles. In some embodiments, phototherapy may use electromagnetic radiation having a broad range of wavelengths/frequencies/colors, including radiation that does not provide effective treatment.
With usage, a light source 11 may have a reduced efficiency (e.g. compared to a similar but brand-new light source). Efficiency may e.g. be expressed as a ratio of supplied/used power and generated level of irradiance. As a result of reduced efficiency (e.g. developed gradually over time with hundreds or thousands of hours of usage), a light source may need more power and/or current to provide the same level of irradiance. In some cases, the efficiency of a particular light source may have been reduced to such an extent that the maximum amount of power and/or current that can (safely) be supplied would not be sufficient to maintain the same level of irradiance as a similar but brand-new light source. By virtue of the techniques described in this disclosure, a recommended level of irradiance for a set of light sources 11 may be automatically maintained by increasing the supplied power and/or current to counteract the reduced efficiency (or estimated reduced efficiency) of the set of light sources 11. System 10 may automatically indicate when one or more light sources need to be replaced based on measurements of the level of irradiance provided and/or generated by at least a subset of light sources 11.
Infant-supporting body 9 in
Set of light sources 11 may emit electromagnetic radiation 12 upon activation. Emitted electromagnetic radiation may be guided through infant-supporting body 9. Electromagnetic radiation 12 may impinge on infant 106 and thus provide phototherapy for infant 106 during operation of system 10. Individual light sources 11 may include one or more of a light-emitting diode (LED), an organic light-emitting diode (OLED), and/or other source of electromagnetic radiation. The LEDs may be configured to emit electromagnetic radiation in a narrow range suitable for phototherapy. In some embodiments, all light sources in the set of light sources may be LEDs. Infant 106 may be monitored while on or near system 10 or a component thereof, e.g. while undergoing phototherapy.
Set of light sources 11 may be arranged in a regular pattern, irregular pattern, or combination of both. For example, light sources 11 may be arranged in a regular grid. The grid includes N rows and M columns, wherein N and M may number between 2 and 40, and/or between other numbers. In a preferred embodiment, N and M are 6 and 21. In some embodiments, as schematically illustrated in
By way of illustration,
Referring to
Sensor(s) 142 of system 10 in
In some embodiments, sensors 142 are configured to generate output signals conveying information related to a level of bilirubin in infant 106. Such sensors can be used to perform interstitial fluids bilirubin measurements.
The illustration of sensor 142 including two members in
In some embodiments, the function of system 10 needs to be accomplished within an incubator environment, such that the micro-climate within the incubator (including one or more of an internal temperature, humidity, and/or other characteristics of a micro-climate within an incubator), is left substantially undisturbed during phototherapy. By way of illustration,
One or more power supplies 30 are configured to supply current and/or power to one or more light sources 11, and/or other components of system 10. As used herein, multiple power supplies in a system such as system 10 may be referred to as “power supply 30.” In preferred embodiments, power supply 30 may be configured to supply direct current rather than alternating current to the one or more light sources 11. By supplying direct current to the one or more light sources 11 upon activation of system 10, electromagnetic interference (EMI), particularly EMI having radio frequencies (RF) may be reduced compared to phototherapy systems that use alternating currents to power one or more light sources.
User interface 120 of system 10 in
By way of non-limiting example, user interface 120 may include a radiation source capable of emitting light. The radiation source includes, for example, one or more of at least one LED, at least one light bulb, a display screen, and/or other sources. User interface 120 controls the radiation source to emit light in a manner that conveys information to user 108.
It is to be understood that other communication techniques, either hard-wired or wireless, are also contemplated herein as user interface 120. For example, in one embodiment, user interface 120 is integrated with a removable storage interface provided by electronic storage 130. In this example, information is loaded into system 10 from removable storage (e.g., a smart card, a flash drive, a removable disk, etc.) that enables the user(s) to customize the implementation of system 10. Other exemplary input devices and techniques adapted for use with system 10 as user interface 120 include, but are not limited to, an RS-232 port, RF link, an IR link, modem (telephone, cable, Ethernet, internet or other). In short, any technique for communicating information with system 10 is contemplated as user interface 120.
Electronic storage 130 of system 10 in
Processor 110 of system 10 in
As is shown in
It should be appreciated that although components 111-114 are illustrated in
Parameter determination component 111 of system 10 in
Control component 112 of system 10 in
Control component 112 may be configured to adjust and/or control the amount of current supplied to set of light sources 11 based on measurements by one or more sensors 142 conveying information related to one or more irradiance levels of electromagnetic radiation emitted by a subset of light sources 11. The subset of light sources that is related and/or used for measurements by one or more sensors 142 may be referred to as the measurement subset (or the measurement subset of light sources). In some embodiments, the measurement subset may include 1 or 2 light sources. In some embodiments, the measurement subset may include 3, 4, 5, or another number of light sources. In some embodiments, the measurement subset includes fewer light sources that set of light sources 11.
In some embodiments, the one or more light sources 11 are controlled using a circuit 40 of panel 15 depicted in
Operation of circuit 40 may be adjustable to at least two settings, for moderate and high levels of intensity of the phototherapy. For example, a moderate level of intensity may correspond to 15·W/cm2/nm, whereas a high level of intensity may correspond to 30·W/cm2/nm or more. Light sources 11 in circuit 40 are driven by a power supply, which may e.g. supply 24V. Variation of the voltage may vary the current through the rows of circuit 40, and thus through the LEDs therein. Adjusting the voltage may correspond to circuit 40 operating in another setting.
In a preferred embodiment of circuit 40, a voltage of 3V per LED may correspond to a 20 mA current going through the LEDs, which in turn correspond to the high level of intensity of 30·W/cm2/nm for the provided phototherapy. Reducing the voltage corresponds to a different operational setting, with a reduced level of intensity for the provided phototherapy.
In some embodiments, one or more (photo-)sensors (or photodiodes) may be mounted on top of a light source (or LED) in the measurement subset of light sources (e.g. connected by optical glue, which may serve to reduce external factors that might otherwise cause an undue influence for measurements). In some embodiments, an LED and a photodiode may be embedded and/or integrated in a package or housing to improve measurement reliability. In some embodiments, light sources in a corner of a panel or circuit may be suitable as elements in the measurement subset, as light sources in the corner may be less likely to contribute to phototherapy under common usage conditions of system 10 (e.g. based on placing an infant centrally on a panel).
In some embodiments, operation of control component 112 is responsive to, and/or controlled by a timer. For example, phototherapy is stopped after a predetermined period of time has elapsed, as indicated by the timer. In some embodiments, the level of intensity of the provided phototherapy is reduced over time, for example gradually from more to less intensive levels (or settings of control component 112 corresponding thereto). For example, control of the level of intensity may be programmed into an algorithm that operates based on one or more of the current intensity level of emitted electromagnetic radiation 12 as determined through a sensor such as sensor 142a and/or sensor 142b, elapsed time of phototherapy according to a timer, prescribed therapy regimen as provided by a caregiver.
In some embodiments, the measurement subset may include a single LED. However, if this LED, for whatever reason, prematurely indicates a reduced efficiency (which in turn may be counteracted by increasing the amount of current provided to this and other LEDs, and/or which in turn may lead to an indication that the set of light sources 11 needs to be replaced) any subsequent action, determination, or decision may likewise be premature. As an improvement, the measurement could include multiple LEDs. For example, the measurement subset could include two LEDs, such that aberrant measurements may be ignored and related premature actions, determinations, and/or decisions avoided. However, individual LEDs in a measurement subset that includes multiple LEDs may convey conflicting information. In some embodiments, a measurement subset may include three LEDs. Control component 112 may be configured to aggregate measurements from multiple LEDs in the measurement subset. For example, control component 112 may be configured to determine and/or select which two LEDs indicate the most similar irradiance level and ignore the outlier measurements from the third LED. The irradiance levels from the selected LEDs may subsequently be used (e.g. by averaging their respective irradiance levels) as described elsewhere herein to adjust the amount of current supplied to set of light sources 11. Reliability and/or quality of the measurements may be improved by increasing the measurement subset to more than three LEDs and/or by applying additional and/or more advanced techniques to remove outlier measurements from consideration prior to adjustments of the power and/or current supplied as described. For example, the measurement subset could include five LEDs and aim one or more strategies to select which LEDs to ignore and which ones to use to create an aggregate (e.g. averaged) value for a measured irradiance level. One strategy may be to ignore the highest and lowest measured level in a measurement subset, and average the remaining measurements. One strategy may compare the measurements and determine which ones fall outside of the distribution, for example based on standard deviation or other statistical techniques and/or analysis. Other strategies, as well as combined strategies, are considered within the scope of this disclosure.
Referring to
Alert component 114 of system 10 in
In some embodiments, method 500 is implemented in one or more processing devices (e.g., a digital processor, a microcontroller, an analog processor, a digital circuit designed to process information, an analog circuit designed to process information, a state machine, and/or other mechanisms for electronically processing information). The one or more processing devices may include one or more devices executing some or all of the operations of method 500 in response to instructions stored electronically on an electronic storage medium. The one or more processing devices may include one or more devices configured through hardware, firmware, and/or software to be specifically designed for execution of one or more of the operations of method 500.
At an operation 502, a set of light sources is activated. The set includes light-emitting diodes (LEDs. In some embodiments, operation 502 is performed by a set of light source the same as or similar to set of light sources 11 (shown in
At an operation 504, electromagnetic radiation is emitted. In some embodiments, operation 504 is performed by a set of light source the same as or similar to set of light sources 11 (shown in
At an operation 506, output signals are generated that convey information related to an irradiance level of electromagnetic radiation emitted by a subset of light sources from the set of light sources. In some embodiments, operation 506 is performed by a photo-sensor the same as or similar to photo-sensor 142 (shown in
At an operation 508, a recommended therapy regimen of electromagnetic radiation is obtained for a subject. In some embodiments, operation 508 is performed by a therapy component the same as or similar to therapy component 113 (shown in
At an operation 510, an irradiance parameter of electromagnetic radiation emitted by the subset of light sources is determined. The irradiance parameter is based on the output signals. In some embodiments, operation 510 is performed by a parameter determination component the same as or similar to parameter determination component 111 (shown in
At an operation 512, an amount of power supplied to the set of light sources is adjusted. Adjustments are based on the recommended therapy regimen and the determined irradiance parameter. In some embodiments, operation 512 is performed by a control component the same as or similar to control component 112 (shown in
In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” or “including” does not exclude the presence of elements or steps other than those listed in a claim. In a device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. In any device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain elements are recited in mutually different dependent claims does not indicate that these elements cannot be used in combination. [55] Although the invention has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to
Filing Document | Filing Date | Country | Kind |
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PCT/IB2014/066036 | 11/14/2014 | WO | 00 |
Number | Date | Country | |
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61908191 | Nov 2013 | US |