Ambient radiation sensing

Abstract

A radiation sensitive device (800, 1000) configured to determine an ambient radiation intensity is disclosed. The device comprises at least one set of optical filters (805) comprising: a first optical filter (810, 1010) having a first passband spanning a portion of a spectrum associated with a radiation emitting device and a portion of an ambient radiation spectrum; and a second optical filter (815, 1015) having a second passband spanning a portion of the spectrum associated with the radiation emitting device and a portion of the ambient radiation spectrum, the second passband being different from the first passband. The device further comprises processing circuitry (830, 1030) configured to determine a contribution of the ambient radiation to intensities of incident radiation sensed using the first and second optical filters based on the intensities of the incident radiation sensed using the first and second optical filters and based on the spectrum associated with the radiation emitting device.

Description

TECHNICAL FIELD

[0001] The present disclosure is in the field of optical devices and relates in particular to ambient radiation sensing. BACKGROUND

[0002] Radiation sensors are commonly used in portable devices such as cellular phones, tablets and smartphones. Such devices typically have a display or screen for presenting information to a user, such as an LED display. The effectiveness of such a display in presenting information to a user can be influenced by ambient radiation. For example, in bright environments characterized by a high degree of ambient radiation, it can be desirable to increase the brightness of the display to increase the overall perceptibility of the displayed information. Similarly, in low-light environments characterized by a low degree of ambient radiation, it can be desirable to decrease the brightness of the display to avoid straining the user’s eyes.

[0003] Furthermore, the display of a portable device can account for a significant proportion of the power consumption and overall battery life of the device. As such, optimizing the brightness of the display based on detected ambient radiation can help to prolong the battery life of a portable device.

[0004] Radiation sensors can provide information about the level of ambient light. Radiation sensors can typically be implemented on such portable devices to enable the portable device to adapt the brightness of the display in response to the detected level of ambient light.

[0005] However, a recent trend in portable device design, in particular of smartphones, is to maximize the display area by reducing the area of the bezel. This can be achieved at least in part by positioning sensors such as radiation sensors and proximity sensors behind the display.

[0006] By mounting the sensors behind the display, the sensitivity of the sensors can be reduced due to the opacity of the display. Furthermore, in some cases, the display itself can emit radiation which can influence the measurement of radiation by a sensor disposed behind the display. That is, a radiation sensor disposed behind the display can detect both ambient radiation passing through the display as well as radiation generated by the display itself. Current solutions to this problem can include complex timing and synchronization of the display and the sensor to minimize the influence of such crosstalk. However, the effectiveness of such an approach can be very dependent on the refresh characteristics of the display, can require complex circuitry and can have limited accuracy.

[0007] It is therefore desirable to provide an effective, accurate and low-complexity ambient radiation sensing solution which is suitable for being arranged behind a display of a portable device. Furthermore, it is also desirable to provide a method of such ambient radiation sensing.

[0008] It is therefore an object of at least one embodiment of at least one aspect of the present disclosure to eliminate or at least mitigate at least one of the above-mentioned drawbacks of the prior art. SUMMARY

[0009] The present disclosure is in the field of optical devices, and in particular ambient radiation sensing. In particular, the present disclosure relates to devices, apparatuses and associated methods for discriminating the contribution of ambient radiation from the overall sensed or detected radiation level.

[0010] According to a first aspect of the present disclosure, there is provided a radiation- sensitive device for determining an ambient radiation intensity. The device comprises at least one set of optical filters comprising: a first optical filter having a first passband spanning a portion of a spectrum associated with a radiation-emitting device and a portion of an ambient radiation spectrum; and a second optical filter having a second passband spanning a portion of the spectrum associated with the radiation-emitting device and a portion of the ambient radiation spectrum, the second passband being different from the first passband. The device further comprises processing circuitry configured to determine, from intensities of incident radiation sensed using the first optical filter and the second optical filter and based on the spectrum associated with the radiation-emitting device, a contribution of the ambient radiation to the intensities of incident radiation sensed using the first optical filter and the second optical filter.

[0011] Advantageously, by making the determination based on the intensities of incident radiation sensed using the first optical filter and the second optical filter and based on the spectrum associated with the radiation-emitting device, the device can be suitable for Behind Organic Light Emitting Diode (BOLED) applications without requiring any synchronization between the OLED display and the sensor implementing the first optical filter and the second optical filter.

[0012] Furthermore, the determination can provide accurate results regardless of whether such OLED display is active (e.g. emitting radiation) or not.

[0013] Advantageously, the radiation-sensitive device according to the first aspect can provide a low-complexity and low-cost means suitable for controlling (e.g. directly or by providing an input to a controller) the brightness of the display in response to the determined contribution of the ambient radiation to the intensities of incident radiation.

[0014] The ambient radiation intensity can correspond to an ambient lux, e.g. an amount of luminous flux per unit area.

[0015] In some embodiments, the ambient radiation intensity can correspond to an ambient intensity of radiation outside the visible spectrum. For example, the ambient radiation intensity can correspond to an intensity of ambient infrared radiation. Advantageously, therefore, the disclosure according to the first aspect can additionally or alternatively be applicable to infrared proximity sensing applications, as described in more detail below.

[0016] The apparatus can comprise a plurality of radiation sensitive elements. For example, each radiation sensitive element can be associated with a channel (e.g. of the apparatus).

[0017] In some embodiments, the first optical filter can be associated with the first radiation sensitive element. That is, the first optical filter can filter radiation incident on the first radiation sensitive element. Similarly, the second optical filter can be associated with the second radiation sensitive element.

[0018] The radiation sensitive apparatus can be an integrated apparatus. For example, the first optical filter, the second optical filter and the processing circuitry or at least a portion of the processing circuitry can be integrated into a package, a module such as a multi-chip module, and / or provided as a monolithic device. Furthermore, the first radiation sensitive element and the second radiation sensitive element can be part of the integrated apparatus.

[0019] The radiation sensitive apparatus can be provided as a distributed system. That is, at least a portion of the processing circuitry and / or storage (such as one or more memory devices associated with the processing circuitry) can be located remotely from the first optical filter, the second optical filter and any associated radiation sensitive elements. For example, at least a portion of the processing circuitry can be provided on one or more servers and / or cloud-based devices. At least a portion of the processing circuitry can be provided on a remote console or client device.

[0020] The processing circuitry can be configured to determine the contribution of the ambient radiation to the intensity of the incident radiation sensed using the first optical filter and the second optical filter by solving the following simultaneous equations to determine ‘a’ and / or ‘y’:

[0021] O F1 = n1 a + Y1 y ——Equation (1)

[0022] O F2 = n2 a + Y2 y ——Equation (2)

[0023] where:

[0024] -a corresponds to the ambient radiation intensity per unit wavelength around the first passband and the second passband;

[0025] - y corresponds to an integral of a spectrum associated with the radiation emitting device.

[0026] - O F1 corresponds to radiation sensed using the first optical filter;

[0027] - O F2 corresponds to radiation sensed using the second optical filter;

[0028] - n1 corresponds to a wavelength range of the first passband;

[0029] - n2 corresponds to a wavelength range of the second passband;

[0030] - Y1 corresponds to a proportion of y corresponding to the first passband; and

[0031] - Y2 corresponds to a proportion of y corresponding to the second passband.

[0032] Advantageously, by determining the intensity of ambient radiation per unit of wavelength in the vicinity of the first and second passbands, a more general estimate of the total amount of ambient radiation can be made. That is, the determined intensity of ambient radiation per unit of wavelength in the vicinity of the first and second passbands can be scaled, extrapolated and / or interpolated to estimate or predict the amount of ambient radiation at wavelengths falling outside the wavelengths in the vicinity of the first and second passbands.

[0033] Advantageously, by determining a value corresponding to an integral of a spectrum associated with the radiation emitting device, the total amount of radiation emitted by the radiation emitting device can be estimated. For example, with knowledge of the emission spectrum associated with the radiation emitting device, the value can be scaled to determine the total emission of the radiation emitting device.

[0034] Advantageously, by determining a value corresponding to an integral of a spectrum associated with the radiation emitting device, the ratio of ambient light to emitted light can be determined. Such a ratio can be used to adjust the brightness of the radiation emitting device relative to the determined intensity of ambient radiation.

[0035] The radiation sensitive device can comprise a third optical filter corresponding to a photopic luminosity function. The determination of the contribution of ambient radiation can comprise subtracting the determined contribution of radiation from the radiation emitting device from the intensity of incident radiation sensed using the third optical filter.

[0036] The photopic luminosity function can be the International Commission on Illumination (CIE) photopic luminosity function y(λ) or V(λ).

[0037] In some embodiments, the third optical filter can be associated with a third radiation sensitive element. That is, the third optical filter can filter radiation incident on the third radiation sensitive element.

[0038] Advantageously, the use of the third optical filter corresponding to the photopic luminosity function can enable the device to sense a contaminated lux, for example, a combination of the intensity of the ambient radiation as perceived by the human eye and the intensity of the emitted radiation. That is, the use of the third optical filter corresponding to the photopic luminosity function can enable the device to sense a total lux, for example, the lux from the environment plus the lux from the radiation emitting device.

[0039] Advantageously, the intensity of the ambient radiation as perceived by the human eye, for example, the ambient lux, can be determined based on subtracting the determined contribution from the radiation emitting device from the contaminated lux.

[0040] The determined radiation contribution from the radiation emitting device can correspond to a product of the photopic luminosity function and a spectrum associated with the radiation emitting device.

[0041] The determined radiation contribution from the radiation emitting device can correspond to a spectral overlap between the photopic luminosity function and a spectrum associated with the radiation emitting device.

[0042] That is, the determined radiation contribution from the radiation emitting device can correspond to an integral of the photopic luminosity function and a spectrum associated with the radiation emitting device, for example, a common area under two curves defined by the photopic luminosity function curve and the spectrum associated with the radiation emitting device.

[0043] Advantageously, by corresponding the photopic luminosity function to the spectrum associated with the radiation emitting device, the determined radiation contribution can correspond to the determined radiation contribution as perceived by the human eye.

[0044] The spectrum associated with the radiation emitting device can be a predetermined or measured spectrum. For example, the spectrum associated with the radiation emitting device can be determined during a calibration phase of the device. Similarly, the photopic luminosity function can be a predetermined photopic luminosity function or can correspond to a spectral sensitivity of the third optical filter.

[0045] The ambient lux can be calculated according to the following equation:

[0046] LUX amb = LUX cont – LUX device — Equation (3)

[0047] LUX device = y LUX unit_area_radiation_spectrum — Equation (4)

[0048] where:

[0049] -LUX ambcorresponding to ambient lux, e.g. the intensity of ambient radiation;

[0050] - LUX cont corresponding to contaminated lux, e.g. the intensity of ambient radiation and radiation from a radiation emitting device;

[0051] - y is a scaling factor determined by solving the simultaneous equations (1) and (2); and

[0052] - LUX device corresponding to the radiation spectrum per unit area of the radiation emitting device, scaled by the scaling factor 'y'.

[0053] The wavelength range of the first passband can substantially overlap the wavelength range of the second passband.

[0054] Advantageously, by having substantially overlapping wavelength ranges, it can be assumed that the spectrum of the ambient radiation is relatively linear over the wavelength range defined by the first and second passbands. In this way, the error in the determined ambient radiation intensity can be minimised.

[0055] In some embodiments, the wavelength range of the first passband can completely overlap the wavelength range of the second passband.

[0056] The at least one set of optical filters can comprise at least one of: a set of filters associated with green LEDs; a set of filters associated with red LEDs; a set of filters associated with blue LEDs; and / or a set of filters associated with infrared radiation sources.

[0057] Advantageously, such a set of optical filters can be suitable for use with RGB displays and / or infrared proximity sensors, such as those implemented on portable devices, cellular telephones, tablet computers, smart phones and the like.

[0058] The device can comprise a plurality of sets of optical filters, each set being associated with a different radiation emitting device. The processing circuitry can be configured to determine a contribution of the ambient radiation to the intensity of the incident radiation corresponding to each different radiation emitting device sensed.

[0059] For example, a set of optical filters associated with green LEDs of an RGB display can comprise a first optical filter having a passband spanning a portion of the spectrum associated with the green LEDs, a second optical filter having a second passband spanning a different portion of the spectrum associated with the green LEDs. The wavelength range of the first passband can substantially overlap the wavelength range of the second passband.

[0060] Similar arrangements of filter sets for each of the red and blue LEDs of an RGB display can also be implemented.

[0061] Advantageously, such a device can be suitable for determining the intensity of ambient radiation in the presence of an RGB display. Moreover, such a device can be suitable for back-of-organic light emitting diode (BOLED) applications, in which the device can be disposed behind an RGB display, and the ambient radiation detected by the device can be contaminated by radiation from the RGB display.

[0062] The ambient lux in the presence of red, green and blue LEDs (e.g., an RGB display) can be calculated according to the following equation:

[0063]

[0064] where:

[0065] LUX amb corresponding to the ambient lux, e.g., the intensity of ambient radiation;

[0066] LUX cont_RGB corresponding to the contaminated lux, e.g., the intensity of ambient radiation and radiation from one or more red, green and blue LEDs;

[0067] y R / G / B corresponding to the integral of the spectrum associated with the red / green / blue LED, as determined by solving the simultaneous equations (1) and (2) for each of the red, green and blue LEDs, or as determined by directly measuring the spectrum associated with each LED (such as under laboratory conditions); and

[0068] LUX LED_unit_area_R / G / B may be determined in a laboratory environment, and can be the integral of the R / G / B_spectrum with the unit area and photopic curve.

[0069] The determined ambient radiation intensity can be a visible and / or infrared ambient radiation intensity.

[0070] Advantageously, the apparatus for determining infrared ambient radiation intensity can be suitable for use in an infrared proximity sensor application. The infrared proximity sensor can comprise an infrared radiation emitting apparatus and one or more infrared radiation sensitive apparatuses for sensing reflected infrared radiation from the infrared radiation emitting apparatus. The one or more radiation sensitive apparatuses can be associated with at least one set of optical filters. The at least one set of optical filters can comprise a first optical filter having a first passband spanning a portion of the spectrum associated with the infrared radiation emitting apparatus and a portion of the ambient infrared radiation spectrum. The at least one set of optical filters can further comprise a second optical filter having a second passband spanning a portion of the spectrum associated with the infrared radiation emitting apparatus and a portion of the ambient infrared radiation spectrum, the second passband being different from the first passband. In this way, by solving the system of equations (1) and (2) to determine 'a', the ambient radiation intensity per unit wavelength in the vicinity of the first passband and the second passband can be determined. Furthermore, the determined ambient radiation intensity per unit wavelength can be scaled according to a particular wavelength range of interest, such as a wavelength range corresponding to the spectral sensitivity of the infrared radiation sensitive apparatus.

[0071] According to a second aspect of the disclosure, there is provided an apparatus comprising: a radiation sensitive apparatus; and at least one radiation emitting apparatus.

[0072] The apparatus can be a portable device, a cellular phone, a tablet computer, a smart phone, etc.

[0073] The at least one radiation emitting apparatus can form a component of an OLED display. The at least one radiation emitting apparatus can form a component of an RGB display. The at least one radiation emitting apparatus can be an LED. The radiation sensitive apparatus can be disposed behind the OLED display and configured to detect radiation passing through the OLED display.

[0074] The OLED display can comprise red, green and blue OLEDs. The at least one radiation sensitive apparatus can comprise: a set of optical filters associated with the red LEDs; a set of optical filters associated with the green LEDs; and a set of optical filters associated with the blue LEDs.

[0075] The apparatus can comprise a camera, wherein the processing circuitry is configured to white balance an image captured by the camera and / or adjust the brightness of an image captured by the camera based at least in part on the determined ambient radiation intensity.

[0076] According to a third aspect of the disclosure, there is provided a proximity sensor comprising: a radiation sensitive apparatus according to the first aspect, and at least one infrared radiation emitting apparatus.

[0077] In some embodiments, the radiation sensitive device and the infrared radiation emitting device can be integrated into a single component, device, and / or package.

[0078] According to a fourth aspect of the disclosure, there is provided a cellular telephone, smart phone, tablet computer device, laptop computer, or portable device comprising an apparatus according to the second aspect and / or a proximity sensor according to the third aspect.

[0079] According to a fifth aspect of the disclosure, there is provided a method of determining an ambient radiation intensity, the method comprising: sensing incident radiation using a first optical filter having a first passband spanning a portion of a spectrum associated with a radiation emitting device and a portion of an ambient radiation spectrum; sensing incident radiation using a second optical filter having a second passband spanning a portion of the spectrum associated with the radiation emitting device and a portion of the ambient radiation spectrum, the second passband being different from the first passband; and determining a contribution of the ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters based on the intensity of the incident radiation sensed using the first and second optical filters and on the spectrum associated with the radiation emitting device.

[0080] Determining the contribution of the ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters can comprise solving equations (1) and (2) to determine 'a' and / or 'y'.

[0081] The method can comprise sensing incident radiation using different plural sets of optical filters, wherein each set comprises a first optical filter and a second optical filter as above. Each set can correspond to a different range of wavelengths. For example, a first set can be selected to substantially correspond to a spectrum associated with a red LED, a second set can be selected to substantially correspond to a spectrum associated with a green LED, and a third set can be selected to substantially correspond to a spectrum associated with a blue LED.

[0082] The method of determining an ambient radiation intensity can comprise determining the contribution of the ambient radiation to the intensity of the incident radiation by solving equations (1) and (2) to determine 'a' and / or 'y' for each set of the different plural sets of optical filters. Further, a weighted sum of the calculated ambient radiation intensities per unit of wavelength for each set of optical filters can be computed.

[0083] Computing the weighted sum can comprise weighting or scaling each of the calculated ambient radiation intensities per unit of wavelength by a scaling factor. Each scaling factor can be a lux coefficient. Each lux coefficient can be a predetermined coefficient. For example, each lux coefficient can be computed or determined under laboratory conditions.

[0084] The above summary is intended to be merely exemplary and non-limiting. This disclosure includes one or more of the corresponding aspects, embodiments or features alone or in various combinations whether or not specifically stated in this summary and whether or not readily apparent from this summary. It should be appreciated that features described above in accordance with any of the aspects of this disclosure or in relation to any specific embodiments of this disclosure below can be used, either alone or in combination with any of the other features expressly mentioned or implied in this disclosure, in any of the other aspects or embodiments or to produce a further aspect or embodiment of this disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0085] These and other aspects of the present disclosure will now be described, by way of example only, with reference to the attached drawings in which:

[0086] Figure 1 A prior art ambient light measurement method is depicted;

[0087] Figure 2 A spectrum associated with ambient light and an RGB display is depicted;

[0088] Figure 3 A method of measuring lux of ambient light and an RGB display is depicted;

[0089] Figure 4 A spectrum associated with ambient light and a green LED is depicted;

[0090] Figure 5a A passband associated with a first optical filter is depicted;

[0091] Figure 5b A passband associated with a second optical filter is depicted;

[0092] Figure 6a A passband associated with a first optical filter and a spectrum associated with a green LED are depicted;

[0093] Figure 6b A passband associated with a second optical filter and a spectrum associated with a green LED are depicted;

[0094] Figure 7a Passbands associated with a plurality of optical filters, spectra associated with a plurality of radiation sources and an ambient light spectrum are depicted;

[0095] Figure 7b A method of determining ambient radiation intensity from a weighted sum of the calculated ambient radiation intensity per unit wavelength is depicted;

[0096] Figure 8 A radiation sensitive device in accordance with embodiments of the disclosure is depicted;

[0097] Figure 9An example apparatus according to embodiments of the disclosure is depicted, which is a smart phone;

[0098] Figure 10 A proximity sensor according to embodiments of the disclosure is depicted; and

[0099] Figure 11 A method of determining ambient radiance according to embodiments of the disclosure is depicted. DETAILED DESCRIPTION

[0100] Figure 1 An example of a prior art method of ambient radiance measurement is depicted. In Figure 1 In the example of FIG. 1, an ambient radiance spectrum 100 associated with an incandescent ambient radiance source (denoted as "TH1") is depicted. It will be appreciated that the incandescent ambient radiance source is for example purposes only, and that the described method is applicable to other ambient radiance sources, which can for example include one or a combination of the following: an incandescent lamp; sunlight; a fluorescent lamp; a halogen lamp; one or more LED lamps; etc.

[0101] In the method depicted in Figure 1 In the method depicted in

[0102] A photopic curve 110 is also depicted. The photopic curve 110 corresponds to a luminosity function that describes the average or typical spectral sensitivity of human visual perception of luminance. The photopic curve can correspond to the CIE photopic luminosity function y( ) or V( ).

[0103] In some examples, the sensor can include an optical filter, such as an interference filter, having a passband characteristic corresponding to the photopic curve 110. In this way, the sensed ambient radiance can correspond to the ambient lux, for example as perceived by the human eye.

[0104] In other examples, the sensor can be configured to sense at least a substantial portion of the visible light range, and can perform subsequent processing operations on the sensed ambient radiance spectrum 100. That is, a function corresponding to the photopic curve 110 can be stored in, for example, a memory of the processing device, and used to calculate the ambient lux using the sensed ambient radiance spectrum 100. For example, the ambient lux can be calculated from an integral of a product of the photopic curve 110 and the sensed ambient radiance spectrum 100.

[0105] Figure 2The spectrum associated with ambient radiation and the RGB display is depicted. Again, for illustrative purposes, the ambient radiation spectrum 210 of the incandescent light source is shown. A first spectrum 220 associated with the blue LED (e.g., indicating radiation emitted by the blue LED), a second spectrum 230 associated with the green LED, and a third spectrum 240 associated with the red LED are also depicted. The first spectrum 220, the second spectrum 230, and the third spectrum 240 may correspond to radiation from an RGB display, such as an OLED RGB display that can be implemented on portable devices, cellular phones, tablets, smartphones, televisions, etc.

[0106] Figure 3 A method for measuring lux of ambient radiation and radiation from this RGB display is described. Spectrum 310 shows the combined radiation from the RGB display and the incandescent ambient radiation source, for example, the linear sum of the radiation. That is, as... Figure 2 The first spectrum 220, the second spectrum 230, the third spectrum 240, and the ambient radiation spectrum 210 shown can be combined by addition to provide Figure 3 The spectrum shown is 310.

[0107] In this way, the above-mentioned steps can be executed. Figure 1 The described method is applied, for example, by integrating the product of the photometric curve 320 and the spectrum 310, to determine a lux value corresponding to the combination of ambient radiation and radiation emitted by the RGB display.

[0108] However, when sensing ambient radiation, it may be desirable to separate the lux contribution from the ambient radiation source from the lux contribution from the RGB display. For example, in BOLED applications where the ambient radiation sensor can be placed behind the display, it may be desirable to be able to assess the intensity of ambient radiation without being affected by any such ambient radiation measurement being contaminated by radiation from the OLED display itself.

[0109] For illustrative and simplicity purposes, reference is made to the incandescent radiation spectrum 410 and the green LED spectrum 430 (e.g., the spectrum associated with a green LED, such as...). Figure 4 The following methods and apparatus for determining ambient radiation intensity are described (as shown). It should be understood that the subsequent methods and apparatus are also applicable to other radiation sources, such as additional red and blue LEDs, and different or additional ambient light sources. The spectrum 430 associated with the green LED is chosen for illustrative purposes only, because spectrum 430 typically overlaps with the photopic curve more than the first spectrum 220 associated with the blue LED and the third spectrum 240 associated with the red LED, and therefore the green LED may typically have the greatest contamination effect on ambient light measurements.

[0110] The disclosed methods and apparatus use a combination of optical filter sets to estimate ambient intensity and / or display intensity. In particular, the disclosed methods and apparatus take advantage of the fact that radiometric intensity can be linearly additive, as shown in Figure 3 where the spectrum 310 shows the combined radiation from an RGB display and an incandescent light source, e.g., linear and.

[0111] The disclosed methods and apparatus use a combination of optical filter sets to derive a similar combination of different linear mixtures of ambient radiation and radiation from a display.

[0112] In particular, the disclosed methods and apparatus employ linear algebra to decouple ambient radiation from radiation from a radiation-emitting device, such as an RGB LED display.

[0113] As described in more detail below, the disclosed methods and apparatus take advantage of prior knowledge of the spectra of the radiation-emitting devices of the display (e.g., a first spectrum 220 associated with a blue LED, a second spectrum 230 associated with a green LED, and / or a third spectrum 240 associated with a red LED) to help determine filter passband locations and ranges.

[0114] According to embodiments of the present disclosure, Figure 5a A first passband 510 associated with a first optical filter is depicted. The first passband 510 spans a portion of the spectrum associated with a radiation-emitting device (e.g., a green LED) and a portion of the ambient radiation spectrum. In Figure 5a the example, the first passband 510 extends from about 492.5 nm to about 537.5 nm. As such, the first passband 510 extends over a portion of the green LED spectrum 430 and the incandescent radiation spectrum 410, as shown in Figure 6a .

[0115] Figure 5b A second passband 520 associated with a second optical filter is depicted. The second passband 520 also spans a portion of the spectrum associated with a radiation-emitting device (e.g., a green LED) and a portion of the ambient radiation spectrum. In Figure 5b the example, the second passband 520 extends from about 502.5 nm to about 527.5 nm. As such, the second passband 520 also extends over a portion of the green LED spectrum 430 and the incandescent radiation spectrum 410, as shown in Figure 6b .

[0116] The first optical filter having the first passband 510 and the second optical filter having the second passband 520 together form a set of optical filters.

[0117] Notably, the second passband 520 is different from the first passband 510. That is, the first optical filter can be configured to sense a different combination of the incandescent radiation spectrum 410 and the green LED spectrum 430 than the second optical filter. While the first filter and the second filter have respective first and second passbands 510, 520 that correspond to different portions of the green LED spectrum 430, the first and second passbands 510, 520 correspond to similar portions of the ambient spectrum. In some embodiments, the first passband 510 can substantially overlap the second passband 520. That is, the wavelength range of the first passband 510 can substantially overlap the wavelength range of the second passband 520. Advantageously, by having substantially overlapping wavelength ranges, it can be assumed that the spectrum of the ambient radiation is relatively linear within the wavelength ranges defined by the first and second passbands 510, 520. As such, errors in the determined ambient radiation intensity can be minimized. The ambient radiation intensity can correspond to an ambient lux, e.g., an amount of luminous flux per unit area.

[0118] In some embodiments, the wavelength range of the first passband 510 can completely overlap the wavelength range of the second passband 520.

[0119] In some embodiments, the device implementing such first and second optical filters can further comprise processing circuitry configured to determine a contribution of the ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters based on a spectrum associated with the radiation emitting device, e.g., the green LED spectrum, from the intensities of the incident radiation sensed using the first and second optical filters.

[0120] Advantageously, by making the determination based on the intensities of the incident radiation sensed using the first and second optical filters and based on the spectrum associated with the radiation emitting device, the device can be suitable for BOLED applications without requiring any synchronization between the OLED display and the sensor implementing the first and second optical filters.

[0121] Continuing the above example, the outputs of the first and second optical filters, e.g., data corresponding to the radiation sensed by the device implementing such first and second filters, can be defined by the above equations (1) and (2). As such, continuing the above example of Figure 6a and Figure 6b the above example, the outputs of the first and second optical filters can be defined by:

[0122] O F1 = 9 a + 0.4417028 y equation (6)

[0123] O F2 = 5 a + 0.2714456 y equation (7)

[0124] where

[0125] -‘a’ corresponds to the ambient radiation intensity per 5 nm around the first passband 510 and the second passband 520;

[0126] -‘y’ corresponds to the integral of the spectrum 430 associated with the green LED;

[0127] O F1 corresponds to the radiation sensed using the first optical filter; and

[0128] O F2 corresponds to the radiation sensed using the second optical filter.

[0129] In equation (6), the proportion of the spectrum 430 corresponding to the first passband 510 is 0.4417028, and in Figure 6a is depicted as the first shaded region 640. Similarly, in equation (6), the proportion of the spectrum 430 corresponding to the second passband 520 is 0.2714456, and in Figure 6b is depicted as the second shaded region 650.

[0130] As an example, for an experiment implementing the above set of optical filters exposed to a green LED and an incandescent ambient radiation source, the lux measurement of the radiation O F1 sensed using the first optical filter was 396.0263 lux, and the lux measurement of the radiation O F2 sensed using the second optical filter was 241.5154 lux.

[0131] In this example embodiment, the simultaneous equations (6) and (7) can thus be solved to determine the parameters “a” and “y”. For example, in some embodiments, the simultaneous equations (6) and (7) can be solved as a matrix operation, where:

[0132]

[0133] In this example embodiment, a = 3.503554. That is, the ambient radiation intensity per 5 nm around the first passband 510 and the second passband 520 is 3.503554 lux.

[0134] In this example embodiment, y = 825.202634. That is, the total integral of the green LED spectrum 430 is 825.202634. This represents the total lux from the green LED.

[0135] In use, knowledge of the parameters "a" and "y" can be used in several different ways, for example to determine information about the intensity of the ambient radiation, to determine the display intensity or brightness, and / or to determine the characteristics of the ambient light source.

[0136] For example, in some embodiments, a "polluted lux" measurement can be made, where the polluted lux represents a measurement of the ambient radiation that is polluted by radiation from the radiation emitting device. In some embodiments, such a measurement can be made with a photopic filter, such that the sensed radiation corresponds to the radiation that would be perceived by the human eye.

[0137] In some embodiments, such a measurement can be made without the use of a photopic filter, for example by a spectral sensor having a spectral sensitivity that substantially spans the visible light range. In such embodiments, a photopic curve (such as a photopic curve stored in a memory of the processing device) can be used to process data corresponding to the sensed radiation to adapt the sensed data to substantially correspond to the radiation that would be perceived by the human eye.

[0138] Continuing with the above example of an ambient radiation source corresponding to an incandescent lamp and a radiation emitting device corresponding to a green LED, in actual experiments, a polluted lux measurement made using a photopic filter was measured to be 703.5435 lux.

[0139] In some embodiments, the scaling factor corresponding to the lux contribution from the green LED can be determined during a calibration phase or in a manufacturing phase, such as under laboratory conditions.

[0140] The scaling factor can correspond to the lux contribution of a unit OLED signal. In the present example, the scaling factor can correspond to the lux contribution of the green LED. That is, the signal corresponding to the spectrum from the green LED is normalized such that the total area under the spectrum is one unit, and then scaled according to the photopic luminosity function.

[0141] That is, in some embodiments, the determined lux contribution from the green LED can correspond to the product of the photopic luminosity function and the spectrum or normalized / unit spectrum associated with the green LED. In some embodiments, the determined radiation contribution from the green LED can correspond to the spectral overlap between the photopic luminosity function and the spectrum or normalized / unit spectrum associated with the green LED.

[0142] In some embodiments, the determined radiation contribution from the green LED can correspond to the integral of the photopic luminosity function and the spectrum associated with the green LED, for example, the common area under the two curves defined by the photopic luminosity function curve and the spectrum associated with the green LED.

[0143] In this example, the scaling factor corresponding to the lux contribution from the green LED is determined to be 0.7117874. As such, the ambient lux can be calculated according to equation (3) above. That is, in this case, the LUX amb corresponding to the ambient lux is determined to be: 703.5435 - 825.202634 0.7117874 = 116.1747 lux. In experiments, this closely corresponds to actual measurements of ambient lux performed in the absence of the green LED.

[0144] Although the above-described apparatus and method have been described by way of example using a green LED, it will be appreciated that the method can be extended to include other or additional radiation-emitting devices, as described above with reference to equation (5). For example, in some embodiments, such an apparatus can be provided behind an RGB display, where the ambient radiation measurements can be contaminated by radiation from at least one or more red, green and / or blue LEDs. Accordingly, the apparatus can implement multiple sets of filters. That is, some embodiments can include using different multiple sets of optical filters to sense the incident radiation, where each set includes a first optical filter and a second optical filter as described above. Each set can correspond to a different wavelength range. For example, a first set can be selected to substantially correspond to the spectrum associated with a red LED, a second set can be selected to substantially correspond to the spectrum associated with a green LED, and a third set can be selected to substantially correspond to the spectrum associated with a blue LED. Such an apparatus is described in more detail below with reference to Figure 8 Such an apparatus is described in more detail below with reference to

[0145] In some embodiments, the determination of the ambient radiation intensity can include determining the contribution of the ambient radiation to the intensity of the incident radiation by solving equations (1) and (2) to determine ‘a’ and / or ‘y’ for each of the different multiple sets of optical filters. Further, a weighted sum of the calculated ambient radiation intensity per unit wavelength for each set of optical filters can be calculated. This is depicted in Figure 7a Figure 7a The passbands 710, 730, 750 associated with the multiple optical filters, the spectra 720, 740, 760 associated with the multiple radiation sources, and the ambient radiation spectrum 770 are shown for illustrative purposes.

[0146] In Figure 7a ​In the example shown, the first set of optical filters has a passband 710 around about 450 nm that substantially overlaps a portion of the spectrum 720 associated with the blue LED. The second set of optical filters has a passband 730 around about 520 nm that substantially overlaps a portion of the spectrum 740 associated with the green LED. The third set of optical filters has a passband 750 around about 620 nm that substantially overlaps a portion of the spectrum 760 associated with the red LED. By applying the above-described method and solving equations (1) and (2) for each of the first, second, and third sets of optical filters, the parameters "a" and "y" can be calculated for each set of filters. As shown in Figure 7a Equation (8), the parameters 'a' and 'y' are represented as: 'al, B' for the first set of filters having a passband 710 corresponding to the blue LED; 'a2, G' for the second set of filters having a passband 730 corresponding to the green LED; and 'a3, R' for the third set of filters having a passband 750 corresponding to the red LED.

[0147] In some embodiments, the determined weighted sum of the parameters al, a2, and a3 can be used to determine a total ambient lux. For example, calculating the weighted sum can include weighting or scaling each of al, a2, a3 by a scaling factor. Each scaling factor can be a lux coefficient. That is, the ambient lux can be determined by equation (7):

[0148] LUX amb = LUX COEFF1 al + LUX COEFF2 a2 + LUX COEFF3 a3 - Equation (8)

[0149] where:

[0150] - LUX amb corresponding to the ambient lux, e.g., the ambient radiance;

[0151] - LUX COEFF1 / 2 / 3 corresponding to a predetermined lux coefficient; and

[0152] - a 1 / 2 / 3 corresponding to the ambient radiance per unit wavelength around the passband of the corresponding filter set.

[0153] Each lux coefficient LUX COEFF1 / 2 / 3 may be a predetermined coefficient. For example, each lux coefficient can be calculated or determined under laboratory conditions. Each lux coefficient can correspond to a particular wavelength or range of wavelengths. For example, LUX COEFF1This can correspond to the wavelength range across the spectrum associated with blue LEDs, LUX COEFF2 This can correspond to a wavelength range across the spectrum associated with green LEDs, and LUX COEFF3 This can correspond to a wavelength range across the spectrum associated with red LEDs.

[0154] In some embodiments, the determined parameters a1, a2, and a3 can be plotted, such as... Figure 7b As shown, each parameter a1, a2, a3 corresponds to the ambient radiation intensity per unit wavelength near the passband of the associated filter bank. In some embodiments, line 780 can be fitted to a point defined by each parameter a1, a2, a3, where the line can be used to identify ambient radiation sources. That is, the shape or other characteristics of the line can correspond to the characteristics of a known ambient radiation source, such as an incandescent lamp, sunlight, a fluorescent lamp, a halogen lamp, one or more LED lamps, etc.

[0155] In some embodiments, the determined parameters a1, a2, and a3 can be plotted, such as... Figure 7b As shown, the resulting line 720 is similar to the photopic curve (e.g., Figure 3 The integral of the visible curve (320) depicted in the figure is used to determine the environmental lux.

[0156] Figure 8 A radiation-sensitive device 800 according to an embodiment of the present disclosure is depicted. The radiation-sensitive device 800 includes: a first set of optical filters 805, the first set of optical filters 805 including: a first optical filter 810 having a first passband spanning a portion of the spectrum associated with the radiating device and a portion of the ambient radiation spectrum; and a second optical filter 815 having a second passband spanning a portion of the spectrum associated with the radiating device and a portion of the ambient radiation spectrum, the second passband being different from the first passband. In an example embodiment, the first optical filter 810 and the second optical filter 815 may be implemented as interferometric filters.

[0157] The first optical filter 810 of the first set of optical filters 805 is associated with the first radiation-sensitive element 820. In an example embodiment, the first radiation-sensitive element 820 may include one or more photodiodes.

[0158] The first optical filter 810 filters the incident radiation such that the first radiation sensitive element 820 receives filtered radiation. In one example embodiment, the passband of the first optical filter 810 corresponds to a portion of the spectrum of the blue LED (e.g., the spectrum 220). That is, the passband of the first optical filter 810 of the first set of optical filters 805 is configured to have a passband that substantially overlaps the spectrum of the radiation emitting device, which in this example embodiment is the blue LED.

[0159] The second optical filter 815 of the first set of optical filters 805 is associated with the second radiation sensitive element 825. The second radiation sensitive element 825 can include one or more photodiodes.

[0160] The second optical filter 815 filters the radiation such that the second radiation sensitive element 825 receives filtered radiation. In one example embodiment, the passband of the second optical filter 815 in this example embodiment also corresponds to a portion of the spectrum of the blue LED. That is, the passband of the second optical filter 815 of the first set of optical filters 805 is also configured to have a passband that substantially overlaps the spectrum of the radiation emitting device, which is the blue LED, and wherein the passbands of the first optical filter 810 and the second optical filter 815 are different.

[0161] The radiation sensitive device 800 also includes processing circuitry 830 configured to determine a contribution of ambient radiation to the intensity of the incident radiation sensed using the first optical filter 810 and the second optical filter 815 as a function of the intensity of the incident radiation sensed using the first optical filter 810 and the second optical filter 815 and based on a spectrum associated with a radiation emitting device (e.g., a red LED).

[0162] The first radiation sensitive element 820 and the second radiation sensitive element 825 are coupled to the processing circuitry 830. In this way, the processing circuitry 830 can receive data and / or signals corresponding to the radiation sensed by each of the first radiation sensitive element 820 and the second radiation sensitive element 825.

[0163] In Figure 8In the example embodiment of the radiation sensitive device 800, the radiation sensitive device 800 further comprises a second set of optical filters 835 comprising a third optical filter 840 associated with a third radiation sensitive element 850 and a fourth optical filter 845 associated with a fourth radiation sensitive element 855. In this example embodiment, the second set of optical filters 835 is associated with a green LED. The third radiation sensitive element 850 and the fourth radiation sensitive element 855 are also coupled to the processing circuitry 830. In this way, the processing circuitry 830 can receive data and / or signals corresponding to radiation sensed by each of the third radiation sensitive element 850 and the fourth radiation sensitive element 855.

[0164] In Figure 8 the example embodiment of the radiation sensitive device 800, the radiation sensitive device 800 further comprises a third set of optical filters 865 comprising a fifth optical filter 870 associated with a fifth radiation sensitive element 880 and a sixth optical filter 875 associated with a sixth radiation sensitive element 885. In this example embodiment, the third set of optical filters 835 is associated with a red LED. The fifth radiation sensitive element 880 and the sixth radiation sensitive element 885 are also coupled to the processing circuitry 830. In this way, the processing circuitry 830 can receive data and / or signals corresponding to radiation sensed by each of the fifth radiation sensitive element 880 and the sixth radiation sensitive element 885.

[0165] The processing circuitry 830 can also be configured to determine the contribution of ambient radiation to the intensity of incident radiation sensed using each of the first set of optical filters 805, the second set of optical filters 835 and the third set of optical filters 865 by solving equations (1) and (2) to determine ‘a’ and / or ‘y’ for each set of filters.

[0166] In this way, the example radiation sensitive device 800 can be used to provide data as shown in Figure 4, where the intensity of ambient radiation per unit wavelength is around the passband of each of the first, second and third filter sets. Figure 7b

[0167] Advantageously, such a device can be suitable for determining the intensity of ambient radiation when the detected ambient radiation is contaminated with radiation from an RGB display. Accordingly, such a device can be particularly suitable for BOLED applications.

[0168] It will be appreciated that the radiation sensitive device 800 is provided for the purposes of example only, and that other embodiments can comprise fewer or more than three sets of filters.

[0169] Furthermore, other embodiments can additionally or alternatively comprise filters having a passband in the infrared range, as described in more detail below with respect to Figure 10 Example Embodiments. ​

[0170] In some embodiments, the radiation sensitive element can be integrated into the radiation sensitive device 800. In some embodiments, an interference filter, such as the first through sixth optical filters 810, 815, 840, 845, 870, 875 described above, can be formed directly on the radiation sensitive element. In some embodiments, such an interference filter can form an assembly of a package or module that includes the radiation sensitive element. In some embodiments, such an interference filter can be formed on or coupled to a display, e.g., a back surface of a display. In some embodiments, the radiation sensitive device 800 can include additional radiation sensitive elements for spectral sensing, proximity sensing, light sensing, and / or other purposes.

[0171] Figure 9 An example apparatus according to embodiments of the disclosure is depicted, which is a smartphone 900. It will be appreciated that the disclosed methods, devices, and apparatuses for determining ambient radiation intensity are also applicable to other devices, such as portable devices, cellular phones, tablet computer devices, televisions, displays, and the like.

[0172] The smartphone includes an RGB display 910. In example embodiments, the RGB display can be an OLED display. The display includes a plurality of radiation emitting elements 915. In Figure 9 example, the radiation emitting elements 915 include red, green, and blue LEDs. The RGB display 910 is coupled to processing circuitry 925, which can directly or indirectly control the brightness of the RGB display 910.

[0173] The smartphone 900 also includes a radiation sensitive device 920 according to embodiments of the disclosure. In some embodiments, the radiation sensitive device 920 can be a device as described above with reference to Figure 8 The processing circuitry 925 is coupled to the radiation sensitive device 920.

[0174] In some embodiments, the radiation sensitive device 920 can be an integrated device. For example, the optical filter and processing circuitry 925 and / or at least a portion of the processing circuitry 925 can be integrated into a package, a module such as a multi-chip module, and / or provided as a monolithic device. In some embodiments, the radiation sensitive device 920 can be provided as a distributed system. That is, at least a portion of the processing circuitry 925 and / or storage devices such as one or more memory devices associated with the processing circuitry 925 can be located remotely from the radiation sensitive device 920. For example, at least a portion of the processing circuitry 925 can be provided on one or more servers and / or cloud-based devices. At least a portion of the processing circuitry 925 can be provided on a remote console or client device.

[0175] As Figure 9As shown, the radiation-sensitive device 920 is disposed behind the display 910. Thus, Figure 9 The use of the radiation-sensitive device 920 in a BOLED application is represented.

[0176] The radiation-sensitive device 920 can be configured to sense ambient radiation propagating through the RGB display 910, as represented by the arrow 935. For example, the RGB display 910 can include one or more holes or transparent regions to enable ambient radiation to propagate through the RGB display 910. In some embodiments, a layer or coating disposed on the back of the RGB display 910 can be partially removed to enable ambient radiation to propagate through the RGB display 910 and be incident on the radiation-sensitive device 920.

[0177] The radiation-emitting elements 915 of the RGB display 910 are configured to emit radiation (e.g., display information) primarily in a direction away from the smartphone 900, as represented by the arrow 930. However, a portion of such radiation can also be incident on the radiation-sensitive device 920, as represented by the double-headed arrow 930.

[0178] The processing circuitry 925 can be configured to determine the contribution of the ambient radiation 935 to the intensity of the incident radiation 930 sensed using the one or more sets of optical filters based on the spectrum associated with the radiation-emitting elements 915 of the RGB display and according to the intensity of the incident radiation sensed using the one or more sets of optical filters as described above with reference to Figure 8 That is, in some embodiments, the processing circuitry 925 can be configured to solve the system of equations (1) and (2) and thus determine the parameters “a” and “y” for each of the one or more sets of optical filters.

[0179] By determining the ambient radiation intensity (e.g., ambient lux), the brightness of the RGB display 910 can be adjusted accordingly to ensure that the user optically views the information presented by the RGB display 910.

[0180] In some embodiments, the radiation-sensitive device can be or can include a proximity sensor.

[0181] A radiation-sensitive device 1000 according to embodiments of the disclosure is depicted, wherein the radiation-sensitive device 1000 is a proximity sensor 1000. Figure 10

[0182] ​The radiation-sensitive device 1000 includes a first optical filter 1010 having a first passband spanning a portion of a spectrum associated with the infrared radiation-emitting device 1050 and a portion of an ambient infrared radiation spectrum, and a second optical filter 1015 having a second passband spanning a portion of the spectrum associated with the infrared radiation-emitting device 1050 and a portion of the ambient infrared radiation spectrum, the second passband being different than the first passband. In example embodiments, the first optical filter 1010 and the second optical filter 1015 can be implemented as interference filters.

[0183] The first optical filter 1010 is associated with a first infrared radiation- sensitive element 1020. In example embodiments, the first infrared radiation- sensitive element 1020 can include one or more photodiodes.

[0184] The first optical filter 1010 filters incident infrared radiation such that the first infrared radiation-sensitive element 1020 receives filtered infrared radiation. In one example embodiment, the passband of the first optical filter 1010 corresponds to a portion of the spectrum of the infrared radiation-emitting device 1050. That is, the passband of the first optical filter 1010 is configured to have a passband that substantially overlaps the spectrum of the infrared radiation-emitting device 1050.

[0185] The second optical filter 1015 is associated with a second infrared radiation- sensitive element 1025. The second infrared radiation-sensitive element 1025 can include one or more photodiodes.

[0186] The second optical filter 1015 filters infrared radiation such that the second infrared radiation-sensitive element 1025 receives filtered infrared radiation. In one example embodiment, the passband of the second optical filter 1015 also corresponds to a portion of the spectrum of the infrared radiation-emitting device 1050. That is, the passband of the second optical filter 1015 is also configured to have a passband that substantially overlaps the spectrum of the infrared radiation-emitting device 1050, and wherein the passbands of the first optical filter 810 and the second optical filter 815 are different.

[0187] The infrared radiation-sensitive device 1000 also includes processing circuitry 1030 configured to determine a contribution of ambient infrared radiation to the intensity of incident infrared radiation sensed using the first optical filter 1010 and the second optical filter 1015 as a function of the intensity of incident infrared radiation sensed using the first optical filter 1010 and the second optical filter 1015 and based on the spectrum associated with the infrared radiation-emitting device 1050.

[0188] The first infrared radiation sensitive element 1020 and the second infrared radiation sensitive element 1025 are coupled to the processing circuit 1030. In this way, the processing circuit 1030 can receive data and / or signals corresponding to infrared radiation sensed by each of the first infrared radiation sensitive element 1020 and the second infrared radiation sensitive element 1025.

[0189] The processing circuit 1030 can also be configured to determine the contribution of ambient radiation to the intensity of incident radiation sensed using each of the first set of optical filters 805, the second set of optical filters 835, and the third set of optical filters 865 by solving equations (1) and (2) to determine ‘a’ and / or ‘y’ for each set of filters.

[0190] In such embodiments, the value ‘a’ can represent the ambient infrared contribution, and ‘y’ can represent the intensity of the infrared radiation emitting device 1050 in the sensed radiation mix.

[0191] By configuring the radiation emitting device 1050 to emit infrared radiation in the direction of the target, such a device can generally be used in proximity sensing applications. One or more radiation sensitive elements, such as the first radiation sensitive element 1020 and the second radiation sensitive element 1025, can detect infrared radiation reflected from the target. The intensity of the reflected radiation can be indicative of the proximity of the target. However, such reflected infrared radiation can be contaminated by ambient infrared radiation, which can result in false alarms and / or missed target detections.

[0192] Advantageously, when used for proximity sensing, such a radiation sensitive device 1000 can be well suited to reduce the incidence of false alarms and / or missed target detections.

[0193] For example, there are at least two conditions that can result in high intensity infrared radiation being incident on the radiation sensitive device 1000. The first condition can be having a relatively distant target in bright sunlight. Under the first condition, the disclosed radiation sensitive device 1000 can readily identify that a large portion of the incident radiation is from ambient infrared radiation, and thus the target is relatively far away, thus reducing false alarms.

[0194] Under the second condition, the target can be relatively close to the radiation sensitive device 1000. In this case, the disclosed radiation sensitive device 1000 can readily identify that a large portion of the incident radiation is reflected radiation from the infrared radiation emitting device 1050 itself, and thus identify a close target and avoid missed target detections from occurring.

[0195] Figure 11A method of determining an intensity of ambient radiation is depicted, the method comprising a first step 1110 of sensing incident radiation using a first optical filter, the first optical filter having a first passband spanning a portion of a spectrum associated with a radiation-emitting device and a portion of a spectrum of ambient radiation.

[0196] The method comprises a second step 1120 of sensing incident radiation using a second optical filter, the second optical filter having a second passband spanning a portion of the spectrum associated with the radiation-emitting device and a portion of the spectrum of ambient radiation, the second passband being different to the first passband.

[0197] It will be appreciated that in some embodiments the first and second steps can occur simultaneously, sequentially and / or in either order.

[0198] The method comprises a third step 1130 of determining a contribution of ambient radiation to the intensity of incident radiation sensed using the first and second optical filters from the intensities of incident radiation sensed using the first and second optical filters and based on the spectrum associated with the radiation-emitting device.

[0199] Although the present disclosure has been described in terms of certain embodiments, it is to be understood that these embodiments are for illustration only and that the claims are not limited to these embodiments. Skilled persons will be able to make modifications and alternatives in view of the present disclosure, which are to be considered to fall within the scope of the claims. Each feature disclosed or shown in the specification can be incorporated into any embodiment whether appearing alone or in any appropriate combination with any other feature disclosed or shown.

[0200]

Claims

1. A radiation-sensitive device (800, 1000) for determining the intensity of ambient radiation, said device comprising: At least one set of optical filters (805), including: The first optical filter (810, 1010) has a first passband that spans a portion of the spectrum associated with the radiative emission device and a portion of the ambient radiation spectrum; A second optical filter (815, 1015) has a second passband spanning a portion of the spectrum associated with the radiating device and a portion of the ambient radiation spectrum, the second passband being different from the first passband; and Processing circuits (830, 1030) are configured to determine the contribution of ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters based on the intensity of the incident radiation sensed using the first and second optical filters and based on the spectrum associated with the radiating device, wherein the processing circuits (830, 1030) are configured to determine the contribution of ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters (810; 815; 1010; 1015) by solving the following simultaneous equations to determine 'a' and / or 'y': About F1 = n1 and + Y1 y Oh F2 = n2 and + Y2 the in: -'a' corresponds to the ambient radiation intensity per unit wavelength near the first passband and the second passband; -'y' corresponds to the integral of the radiant intensity of the spectrum associated with the radiating device; -O F1 Corresponding to the radiation sensed using the first optical filter (810, 1010); -O F2 Corresponding to the radiation sensed using the second optical filter (815; 1015); -n1 corresponds to the wavelength range of the first passband; -n2 corresponds to the wavelength range of the second passband; Y1 corresponds to the proportion of y corresponding to the first passband; and Y2 corresponds to the proportion of y that corresponds to the second passband.

2. The radiation-sensitive device (800, 1000) according to claim 1, comprising a third optical filter corresponding to a photometric function, wherein the determination of the contribution of ambient radiation comprises subtracting the determined radiation contribution from the radiating device from the intensity of incident radiation sensed using the third optical filter.

3. The radiation-sensitive device (800, 1000) according to claim 2, wherein the determined radiation contribution from the radiative emitting device corresponds to the product of the photometric function and the spectrum associated with the radiative emitting device.

4. The radiation-sensitive device (800, 1000) according to any one of claims 1-3, wherein the wavelength range of the first passband substantially overlaps with the wavelength range of the second passband.

5. The radiation-sensitive device (800, 1000) according to any one of claims 1-3, wherein, The at least one set of optical filters includes at least one of the following: A set of filters associated with the green LED; A set of filters associated with the red LED; A set of filters associated with the blue LED; and / or A set of filters associated with an infrared radiation source.

6. The radiation-sensitive device (800, 1000) according to any one of claims 1-3, comprising a plurality of optical filters, each associated with a different radiation emitting device, and wherein the processing circuitry is configured to determine the contribution of ambient radiation to the intensity of incident radiation sensed corresponding to each of the different radiation emitting devices.

7. The radiation-sensitive device (800, 1000) according to any one of claims 1-3, wherein the determined ambient radiation intensity is visible and / or infrared ambient radiation intensity.

8. An optical device, comprising: Radiation-sensitive device (1000) according to any one of claims 1-7. At least one radiation emitting device (1050).

9. The optical device of claim 8, wherein the at least one radiation emitting device forms an assembly of an OLED display (910), and wherein the radiation-sensitive device is disposed behind the OLED display and configured to detect radiation passing through the OLED display.

10. The optical device of claim 9, wherein the OLED display (910) comprises red, green, and blue OLEDs, and wherein the at least one radiation-sensitive device (1000) comprises: A set of optical filters associated with the red LED; A set of optical filters associated with the green LED; And a set of optical filters associated with the blue LED.

11. The optical device of claim 9 or 10, comprising a camera, wherein the processing circuitry is configured to perform white balance on an image captured by the camera and / or adjust the brightness of the image captured by the camera based at least in part on a determined ambient radiation intensity.

12. A proximity sensor, comprising: Radiation-sensitive device according to any one of claims 1 to 7; At least one infrared radiation emitting device.

13. A portable device comprising an optical device according to any one of claims 8 to 11 and / or a proximity sensor according to claim 12.

14. The portable device of claim 13, wherein the portable device includes a cellular phone, a smartphone (900), a tablet computer device, or a laptop computer.

15. A method for determining ambient radiation intensity, the method comprising: Use the first optical filter (810); 1010) Sensing incident radiation, the first optical filter having a first passband spanning a portion of the spectrum associated with the radiating device and a portion of the ambient radiation spectrum; Use a second optical filter (815); 1015) Sensing the incident radiation, the second optical filter having a second passband spanning a portion of the spectrum associated with the radiation emitting device and a portion of the ambient radiation spectrum, the second passband being different from the first passband; as well as The contribution of ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters is determined based on the intensity of the incident radiation sensed using the first and second optical filters and on the spectrum associated with the radiating device. Determining the contribution of ambient radiation to the intensity of the incident radiation sensed using the first and second optical filters (810; 815; 1010; 1015) involves solving the following simultaneous equations to determine 'a' and / or 'y': About F1 = n1 and + Y1 y Oh F2 = n2 and + Y2 the in: -'a' corresponds to the ambient radiation intensity per unit wavelength near the first passband and the second passband; -'y' corresponds to the integral of the radiant intensity of the spectrum associated with the radiating device; -O F1 Corresponding to the radiation sensed using the first optical filter; -O F2 Corresponding to the radiation sensed using the second optical filter; -n1 corresponds to the wavelength range of the first passband; -n2 corresponds to the wavelength range of the second passband; -Y1 corresponds to the proportion of y corresponding to the first passband; and -Y2 corresponds to the proportion of y that corresponds to the second passband.

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