Very low cyanosis observation index high efficacy light source

Abstract

According to certain embodiments, an electronic device comprises: one or more cool white light emitting diodes (LEDs); one or more warm white LEDs; one or more cyan LEDs; and one or more Royal Blue LEDs.

Description

[0001] Very low cyanosis observation index high efficacy light source

[0002] FIELD

[0003] The disclosure relates to light sources for healthcare applications. More particularly, the disclosure relates to light sources for healthcare applications where a low Cyanosis Observation Index is desired.

[0004] DESCRIPTION OF THE RELATED ART

[0005] Diagnosing medical conditions sometimes relies on detection and observation of the redness of the patient’s tissue resulting from trauma, which may be hard to detect in patients with dark skin. Other times, medics may be concerned about cyanosis, which is the result of poor blood oxygen. In both cases, the color quality of the light source is critical in rendering the redness of healthy tissue for comparison. However, light sources may not always provide the required color quality, which usually reduces efficacy due to the increase in the proportion of red, relative to the other colors. One quality measure of a light source to render blood rich tissue is the Cyanosis Observation Index (COI), Australian Standard AS1680.2.5: 1997. Thus, it may be desirable for some application to provide a high color quality light source that provides a very low COI value while maintaining high efficacy.

[0006] US 2016 / 298813 Al describes LED die and die on circuit board configurations used in combination with elongated homogenizers to achieve uniform lights with a wider color gamut.

[0007] CN 114 270 511 A describes a full spectrum white light emitting device, which may include: a broadband solid state excitation source for generating broadband excitation light having a dominant wavelength from about 420nm to about 480nm and a FWHM intensity greater than about 25 nm; and a narrow-band red photoluminescent material having an emission peak wavelength from about 620nm to about 640nm and a FWHM intensity of less than about 30 nm. The device has an efficacy of at least 1301m / W and produces white light having a CRI Ra >90 and wherein the maximum percent intensity deviation of the white light from the intensity of light of the black body curve or CIE standard illuminant D is less than about 50% over a wavelength range from about 430nm to about 520 nm. WO 2020 / 097579 Al describes a bioactive display systems for displaying digital content. The display systems have one or more LED-based lighting channels adapted to generate one or more of a long red near infrared (LRNE) red light, a circadian-inducing blue light output in first operational mode and a less-circadian-inducing blue light output in a second operational mode. The bioactive lighting can have a first circadian-stimulating energy characteristic related to the associated first spectral power distributions of light generated m the first operational mode, and the non-circadian-inducing blue light can have a second circadian-stimulating energy characteristic related to the associated second spectral power distribution of light generated in the second operational mode. The methods can generate a circadian-inducing blue light output in first operational mode and one of a LRNE output and a less-circadian-inducing blue light output in a second operational mode.

[0008] SUMMARY

[0009] According to certain embodiments, a lighting device comprises a light source configured to provide a low Cyanosis Observation Index (COI) white light having a total flux, the light source comprising: a first group of one or more light emitting diodes (LEDs) configured to provide cool white light; a second group one or more LEDs configured to provide warm white; a third group of one or more LEDs configured to provide cyan light; a fourth group of one or more LEDs configured to provide Royal Blue light, and wherein the low COI white light is a combination of light from the four groups of one or more LEDs, and wherein the cyan light contributes less than 10% of the total flux and the Royal Blue light contributes between 0.09-0.11% of the total flux, and wherein the COI of the low COI white light is .33 or lower.

[0010] According to certain embodiments, a method for providing a light source having a low Cyanosis Observation Index (COI) white light having a total flux, the method comprises a light source configured, the light source comprising, providing a first portion of a total flux of the light source with one or more cool white light emitting diodes (LEDs); providing a second portion of the total flux of the light source with one or more warm white LEDs; providing a third portion of the total flux of the light source with one or more cyan LEDs; providing a fourth portion of the total flux of the light source with one or more Royal Blue LEDs, and wherein the low COI white light is a combination of light from the four groups of one or more LEDs and wherein the third portion contributes is less than 10% of the total flux of the light source and the fourth portion is contributes between 0.09-0.11% of the total flux of the light source., and wherein the COI of the low COI white light is .33 or lower..

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0013] Fig. l is a block diagram of a lighting device in accordance with an embodiment of the disclosure;

[0014] Fig. 2 is a spectral power distribution (SPD) diagram of resultant light from mixing light from cool white light and warm white light in accordance with an embodiment of the disclosure;

[0015] Fig. 3 is a chromaticity chart or color space that shows the chromaticity point of the resultant light from mixing light from cool white light and warm white light that lies below the black body curve, in accordance with an embodiment of the disclosure;

[0016] Fig. 4 is an SPD diagram of cyan light in accordance with an embodiment of the disclosure;

[0017] Fig. 5 is the SPD diagram of royal blue light in accordance with an embodiment of the disclosure;

[0018] Fig. 6 is the SPD diagram of resultant light of Fig. 2 and Fig. 3 with the addition of Cyan and Royal blue for improving color quality in accordance with an embodiment of the disclosure;

[0019] Fig. 7 is a chromaticity chart or color space that shows the chromaticity point of the resultant light in Fig. 6 relative to the black body in accordance with an embodiment of the disclosure;

[0020] Fig. 8 is a method for providing a light source in accordance with an embodiment of the disclosure; and

[0021] Fig. 9 is a block diagram of a luminaire in accordance with an embodiment of the disclosure.

[0022] DETAILED DESCRIPTION

[0023] It should be appreciated that various embodiments of the present disclosure and the terms used therein are not intended to limit the technological features set forth herein to particular embodiments and include various changes, equivalents, or replacements for a corresponding embodiment. With regard to the description of the drawings, similar reference numerals may be used to refer to similar or related elements. It is to be understood that a singular form of a noun corresponding to an item may include at least one of the things, unless the relevant context clearly indicates otherwise. As used herein, each of such phrases as "A or B," "at least one of A and B," "at least one of A or B," "A, B, or C," "at least one of A, B, and C," and "at least one of A, B, or C," may include any one of, or all possible combinations of the items enumerated together in a corresponding one of the phrases. As used herein, such terms as "1st" and "2nd," or "first" and "second" may be used to simply distinguish a corresponding component from another, and does not limit the components in other aspect (e.g., importance or order). It is to be understood that if an element (e.g., a first element) is referred to, with or without the term "operatively" or "communicatively", as "coupled with," "coupled to," "connected with," or "connected to" another element (e.g., a second element), it means that the element may be coupled with the other element directly (e.g., wiredly), wirelessly, or via a third element.

[0024] As used herein, the term "module" may include a unit implemented in hardware, software, or firmware, and may interchangeably be used with other terms, for example, "logic," "logic block," "part," or "circuitry". A module may be a single integral component, or a minimum unit or part thereof, adapted to perform at least one functions. For example, according to an embodiment, the module may be implemented in a form of an application-specific integrated circuit (ASIC).

[0025] It shall be understood in this document that “detection” or “detecting” a condition is not necessarily direct detection or detecting of the condition. For example, detection of a condition can include detection of a circumstance that logically implies the condition.

[0026] It shall also be understood that an action that occurs “in response to,” “responsive to”, or “when” to an event, shall not be limited to directly “in response to”, “responsive to” or “when” the event occurs or to the first action that occurs, but may be “in response to,” “responsive to,” or “when” any number of other intervening actions that logically imply that the event has occurred.

[0027] Referring now to Fig. 1, there is illustrated a block diagram of a lighting device 100 that may produce white light with a low Cyanosis Observation Index (COI), in accordance with an embodiment of the disclosure. The lighting device can include a driver 105, a controller 110, and a light source 115. The light source 115 includes 4 groups (first, second, third and fourth groups) of one or more LEDs 120a, 120b, 120c, and 120d. The controller 110 may control the amount of current that the driver 105 provides to each of the respective groups one or more LEDs 120a, 120b, 120c, and 120d, including the portion of currents via electrical wires or conductive traces on a printed circuit board (PCB).

[0028] The controller 110 may control the amount of current that the driver provides to each of the respective one or more LEDs 120a, 120b, 120c, and 120d based either on a default configuration, or a user input provided via a user interface. The user interface may receive user input wirelessly, via a wired connection, or via direct user input. The controller 110 may include, for example, a processor, such as a central processing unit (CPU). The terms “controller”, “processor”, and “CPU” shall be understood to refer to both the singular and plural contexts.

[0029] In certain embodiments, driver 105 may provide a constant source of current to each group of the one or more LEDs 120a, 120b, 120c, and 120d.

[0030] The first one or more LED 120a may comprises one or more cool white LED providing a cool white light (6500K to 5000K). The second one or more LED 120b may provide one or more warm white LED providing a warm white light (<3000K). In this document, a correlated color temperature (CCT), e.g., 6500K, shall refer to the color that a black body has at the respective temperature measured in Kelvin. The third one or more LED 120c may provide a cyan light having a wavelength between 480nm and 510nm. The fourth one or more LED 120d may provide a royal blue light having a wavelength between 425nm and 475nm. In certain embodiments, the percentage flux contribution of the one or more cool white LEDs (6500K to 5000K by the one or more LEDs 120a), the one or more warm while LEDs (< 3000K by the one or more LEDs 120b), the one or more cyan light (by the one or more third LEDs 120c) and the one or more royal blue light (by the fourth one or more LED 120d) may be 33.7%, 57.1% 2700K, 9.1%, and 0.1%, respectively. In certain embodiments, the respective ranges may be between 56-58%, 32-35%, less than 10%, and between 0.09- 0.11%.

[0031] Fig. 2 describes a spectral diagram of the resultant light from mixing light from the first one or more LEDs (providing cool white light 6500K to 5000K) and the second one or more LED 120b (providing warm white light <3000K), in accordance with an embodiments of the disclosure. The horizontal axis represents the wavelengths in nanometers while the vertical axis represents intensity.

[0032] However, Fig. 3 compares the resultant light against a block body curve in accordance with an embodiments of the disclosure. The resultant correlated color temperature is a linear combination of the two flux outputs where the resultant chromaticity lies on a straight line between the color temperature between the color correlated temperatures of the first one or more LEDs 120a and the second one or more LEDs 120b. As can be seen in Fig. 3, the resultant color correlated temperature will be close to 4000K (3606K) but will be pushed below the black body curve.

[0033] Cyan and royal blue light are added to move the chromaticity point closer to the black body curve and to improve color quality and COI. Referring now to Fig. 4, there is illustrated the wavelength spectrum of the light from the third one or more Cyan LED 120c in accordance with an embodiments of the disclosure. The peak wavelength is between 480 and 520 nm. and centered at 490nm.

[0034] Referring now to Fig. 5, there is illustrated the wavelength spectrum of the light from the fourth one or more Royal Blue LED 120d in accordance with an embodiments of the disclosure. The peak wavelength is between 430 and 470 nm and centered at 450nm.

[0035] Referring now to Fig. 6 and 7, there are illustrated the properties of the resultant light from mixing light from the light from 4 one or more LEDs 120a, 120b, 120c, and 120d in accordance with an embodiment of the disclosure. The resultant light can be from 33.7% cool white light 6500K to 5000K (from one or more LEDs 120a), 57.1% warm white light <3000K (from one or more LEDs 120b), < 10% cyan light (from one or more LEDs 120c), and between 0.09% to 0.11% royal blue light (from one or more LEDs 120d). Fig. 6 describes the SPD diagram of the resultant light in accordance with an embodiments of the disclosure. Fig. 7 compares the resultant chromaticity point against a block body curve in accordance with embodiments of the disclosure. As can be seen in Fig. 7, the resultant color correlated temperature will be close to 4000K (4274K) and above the black body curve.

[0036] Table describes various properties of the resultant light:

[0037] Significantly less than 3.3

[0038] Pass P1 F3

[0039] A mix of 33.7% 6500K, 57.1% 2700K, 9.1% Cyan and 0.1% Royal Blue

[0040] Table 1

[0041] In contrast, a 4000K high color quality LED, of the same type as the cool white and warm white LEDs used in the embodiment, will have a significantly higher COI and lower color quality as shown in table 2. Less than 3.3 Fail P1 F3

[0042] 4000K KSF Phosphor LED Table 2

[0043] As can be seen, a COI of 0.33 is achieved, significantly less than the standard requirement of 3.3.

[0044] Referring now to Fig. 8, there is illustrated a method for providing a light source. Recitation of the method operations in particular order shall not be understood to imply that the steps are performed in the foregoing order. Moreover, in certain embodiments, the operations may be performed simultaneously or in parallel, while in other embodiments, the operations may be performed in a sequence. The method comprises providing a first portion 805 of a total flux of the light source with one or more cool white light emitting diodes LEDs 120a. At 810, the method comprises providing a second portion of the total flux of the light source with one or more warm white LEDs 120b. At 815, the method comprises providing a third portion of the total flux of the light source with one or more cyan LEDs 120c. At 820, the method comprises providing a third portion of the total flux of the light source with one or more royal blue LEDs.

[0045] Referring now to Fig. 9, there is illustrated a block diagram of a luminaire 900 in accordance with an embodiment of the disclosure. The luminaire includes a power source 905, a dimmer 910, a power supply 915, input device 920, and an LED module 925. The power supply 915 includes a controller 930, a voltage source 935, and a pulse width modulation current source 940.

[0046] According to certain embodiments, the LED module 925 includes white LEDs 942 and color enhancement LEDs 945, one or more white 6500K to 5000K LEDs 942b, and one or more white 3000K or less LEDs 942c. In certain embodiments, the one or more white LEDs 942 can have an R9 of greater than 50 and can comprise KSF phosphor white LEDs. The one or more white LEDs 942 allows the user to realize color temperatures within a range by mixing specific proportions of the one or more white LEDs 942. However, the resultant chromaticity lies on a straight line connecting the two color correlated temperature points below the black body curve.

[0047] The color enhancement LEDs 945 correct this. The color enhancement LEDs 945 can include one or more cyan LEDs 945a, one or more Royal Blue LEDs 945b, Lime 945c, and one or more amber LEDs 945d. The color enhancement LEDs 945, in combination with the one or more white LEDs 940 allows realization of color correlated temperatures in a broad range with delta uv (duv) correction.

[0048] According to certain embodiments, the controller 930 can include a microprocessor, a processor, a CPU, as well as memory. In certain embodiments, the memory can include a look-up table with associating different color correlated temperatures with different flux ratios of the different white LEDs 942 and the color enhancement LEDs 945.

[0049] Certain embodiments are directed to a lighting device 100 comprising: one or more cool white light emitting diodes LEDs 120a; one or more warm white LEDs 120b; one or more cyan LEDs 120c; and one or more Royal Blue LEDs 120d.

[0050] According to certain embodiments, the one or more cool white LEDs 120a have a color temperature between 6500K to 5000K. According to certain embodiments, the one or more warm white LEDs 120b have a color temperature below 3000K.

[0051] According to certain embodiments, the one or more cyan LEDs 120c have a peak wavelength between 480nm and 510nm.

[0052] According to certain embodiments, the one or more Royal Blue LEDs 120d have a wavelength between 425nm and 475nm.

[0053] According to certain embodiments, the one or more cyan LEDs 120c provide less than 10% of the light output by the electronic device and the one or more Royal Blue LEDs 120d outputs between 0.09-0.11% of the light output by the lighting device.

[0054] According to certain embodiments, the one of more cool white LEDs 120a provide between 56-58% of the light output by the electronic device and the one or more warm white LEDs 120b provide between 32-35% of the light output by the electronic device.

[0055] According to certain embodiments, the one or more cool white LEDs 120a and the one or more warm white LEDs 120b comprise a phosphor KSF white LED.

[0056] According to certain embodiments, a method for providing a light source comprises: providing a first portion 805 of a total flux of the light source with one or more cool white light emitting diodes LEDs 120a; providing a second portion 810 of the total flux of the light source with one or more warm white LEDs 120b; providing a third portion 815 of the total flux of the light source with one or more cyan LEDs 120c; and providing a fourth portion 820 of the total flux of the light source with one or more Royal Blue LEDs 120d.

[0057] According to certain embodiments, the one or more cool white LEDs 120a have a color temperature between 6500K to 5000K.

[0058] According to certain embodiments, the one or more warm white LEDs 120b have a color temperature below 3000K.

[0059] According to certain embodiments, the one or more cyan LEDs 120c have wavelengths between 480nm and 510nm.

[0060] According to certain embodiments, the one or more Royal Blue LEDs 120d have a wavelength between 425nm and 475nm.

[0061] According to certain embodiments, the third portion is less than 10% of the total flux of the light source and the fourth portion is between 0.09-0.11% of the total flux of the light source.

[0062] According to certain embodiments, the first portion is between 56-58% of the total flux of the light source and the second portion is between 32-35% of the total flux of the light source. According to an embodiment, a method according to various embodiments of the disclosure may be included and provided in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read only memory (CD-ROM)), or be distributed (e.g., downloaded or uploaded) online via an application store (e.g., PlayStore™), or between two user devices (e.g., smart phones) directly. If distributed online, at least part of the computer program product may be temporarily generated or at least temporarily stored in the machine-readable storage medium, such as memory of the manufacturer's server, a server of the application store, or a relay server.

[0063] While at least one embodiments of the disclosure have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.

Claims

CLAIMS:

1. A lighting device (100) comprising: a light source configured to provide a low Cyanosis Observation Index (COI) white light having a total flux, the light source comprising: a first group of one or more light emitting diodes (LEDs) 120a configured to provide cool white light; a second group one or more LEDs 120b configured to provide warm white; a third group of one or more LEDs 120c configured to provide cyan light ; a fourth group of one or more LEDs 120d configured to provide Royal Blue light, and wherein the low COI white light is a combination of light from the four groups of one or more LEDs (120a-d), and wherein the cyan light contributes less than 10% of the total flux and the Royal Blue light contributes between 0.09-0.11% of the total flux, and wherein the COI of the low COI white light is .33 or lower..

2. The lighting device 100 of claim 1, wherein the first group of one or more cool white LEDs 120a have a color temperature between 6500K to 5000K.

3. The lighting device 100 of claim 1, wherein the second group of one or more warm white LEDs 120b have a color temperature below 3000K.

4. The lighting device 100 of claim 1, wherein the third group of one or more cyan LEDs (120c) have wavelengths between 480nm and 510nm.

5. The lighting device 100 claim 1, wherein the fourth group of one or more Royal Blue LEDs 120d have a wavelength between 425nm and 475nm.

6. The lighting device 100 of claim 1, wherein the first group of one of more cool white LEDs 120a provide between 56-58% of the light output by the lighting device and thesecond group of one or more warm white LEDs 120b provide between 32-35% of the light output by the lighting device.

7. The lighting device 100 of claim 1, wherein the first group of one or more cool white LEDs 120a and the second group of one or more warm white LEDs 120b comprise a phosphor KSF white LED.

8. A method for providing a light source having a low Cyanosis Observation Index (COI) white light having a total flux, the method comprising: a light source configured, the light source comprising: providing a first portion 805 of a total flux of the light source with one or more cool white light emitting diodes (LEDs) 120a; providing a second portion 810 of the total flux of the light source with one or more warm white LEDs (120b); providing a third portion 815 of the total flux of the light source with one or more cyan LEDs 120c; providing a fourth portion 820 of the total flux of the light source with one or more Royal Blue LEDs 120d, and wherein the low COI white light is a combination of light from the four groups of one or more LEDs and wherein the third portion contributes less than 10% of the total flux and the fourth portion contributes between 0.09-0.11% of the total flux of the light source, and wherein the COI of the low COI white light is .33 or lower.

9. The method of claim 8, wherein the first group of one or more cool white LEDs 120a have a color temperature between 6500K to 5000K.

10. The method of claim 8, wherein the second group of one or more warm white LEDs 120b have a color temperature below 3000K.

11. The method of claim 8, wherein the third group of one or more cyan LEDs 120c have wavelengths between 480nm and 510nm.

12. The method of claim 8, wherein the fourth group of one or more Royal Blue LEDs 120d have a wavelength between 425nm and 475nm.

13. The method of claim 8, wherein the first portion is between 56-58% of the total flux of the light source and the second portion is between 32-35% of the total flux of the light source.

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