Adaptive photobiomodulation (PBM)

Abstract

An electro-optical device (1) has a radiation unit (10) for emitting a pulsed radiation beam (11) having a peak emission wavelength between 610-1400 nm, a detection unit (20) for detecting a predetermined region of a user's body, and a radiation control unit (30) for receiving an input from the detection unit. The electro-optical device (1) is adapted to direct the radiation beam (11) to a predetermined area using the radiation control unit (30) such that the radiation beam has a peak illumination intensity higher than 0.1 mW / cm2 at the surface of the body of the user in the predetermined area.

Description

Technical Field

[0001] The present invention relates to a device for delivering radiation sufficient to induce a photobiomodulation (PBM) effect. Background Art

[0002] Photobiomodulation (PBM) involves irradiating a living organism with a certain energy / power level to induce a biological or biochemical response. The irradiation can be in the visible spectrum, such as red light, or in the invisible spectrum, such as infrared (IR). There has been a large amount of research on the medical benefits of using PBM therapy to treat physical and psychological symptoms.

[0003] However, most devices apply PBM radiation near-field excitation (i.e., close to the device) to the skin or treatment area, or use very high power to irradiate the entire body. These specifications make the PBM effect only applicable to specialized medical or therapeutic devices that are often bulky and / or expensive. These factors greatly limit the public's access to the medical benefits of PBM.

[0004] In the applicant's PCT applications published as WO 2020 / 119965 and WO 2021 / 099642 (incorporated herein by reference in their entirety), the concept of incorporating PBM into general lighting is proposed, using a lighting device for emitting steady visible light and additionally emitting pulsed PBM radiation. By driving the radiation source with a pulse rather than a continuous wave (or near-continuous wave) signal, the peak power can be increased during the pulse to achieve a PBM response. This allows the general lighting device to emit a sufficient amount of power to achieve a specific power density (irradiance) at a specific distance that can induce a PBM response. A sensor is provided in such a lighting device to turn the PBM radiation on or off based on the presence and / or distance of the user.

[0005] However, in order to emit an amount of radiation sufficient to induce a PBM response, known PBM devices still require a considerable amount of energy to induce a PBM response, and a significant amount of time to achieve a desired dose level. Summary of the invention

[0006] The object of the present invention is to provide a device that is more efficient with respect to the energy required to induce a PBM response and with respect to the time required to achieve a desired dose level. In particular, it is desirable to implement such a device in non-professional devices used in normal daily activities (e.g., smartphones, tablet computers, laptops, televisions, lighting equipment, etc.).

[0007] A first aspect of the invention relates to an electro-optical device. The device may include a radiation unit adapted to emit a radiation beam, a detection unit adapted to detect a predetermined area of ​​a user's body (e.g., a user's face), and a radiation control unit for receiving input from the detection unit. The electro-optical device may be adapted to: direct the radiation beam to the predetermined area using the radiation control unit so that the radiation beam has a power higher than 0.1 mW / cm at the surface of the user's body in the predetermined area. 2 The peak irradiation intensity.

[0008] The present invention is based on the insight that well-known detection methods (e.g., face detection) can be used to give useful information not only about the presence of the user itself, but also about the relative position between the device and the user (e.g., the direction and / or distance from the device to the user). Using such information, the electro-optical device can direct the radiation beam to a predetermined area in a more directional and / or focused manner, while reducing unnecessary radiation outside the predetermined area and wasting less energy.

[0009] The radiation control unit may be adapted to control the radiation unit to adaptively adjust the radiation pattern (e.g., beam direction, beam angle, focus, or a combination of these) of the radiation beam based on input from the detection unit. In this way, the electro-optical device may adaptively adjust the radiation pattern, rather than simply switching the entire PBM radiation on and off, thereby fully generating a PBM response in an efficient manner. Optionally, the radiation beam may be pulsed, as described in WO2020 / 119965 and WO 2021 / 099642.

[0010] In a preferred embodiment, the predetermined area covers at least a portion of the user's face. This has several advantages. First, face detection methods are well known and well developed, which makes implementation simpler and less expensive. Second, the skin on the face is typically not covered by clothing and provides a relatively large area (the average surface area of ​​a male face is 1323 cm 2 ). By directing the radiation beam towards at least a portion of the user's face, the PBM effect can be achieved in a particularly efficient manner. Preferably, the predetermined area covers substantially the entire face of the user, including the user's eyes, mouth and nose.

[0011] The radiation pattern refers to the way in which the radiation beam is emitted (e.g. beam angle, direction, illuminated area, transmission power, etc.). Controlling the radiation pattern enables the electro-optical device to steer the radiation beam towards a predetermined area of ​​the user even when the user moves. In this way, less energy is wasted to induce a PBM response, and the accumulated energy in the predetermined area also enables a desired dose level to be achieved more quickly. In an embodiment, the radiation control unit is adapted to: adjust the radiation pattern to substantially cover only the predetermined area.

[0012] The radiation pattern can be controlled in various ways. For example, the radiation pattern can be adjusted (e.g., steered, focused, etc.) by optical elements (e.g., lenses, reflectors, etc.). Alternatively or additionally, a multi-element transmitter can be used (e.g., using multiple LEDs or VCSEL arrays in the radiation unit). Each radiating element in the multi-element transmitter can be arranged to map to an effective illumination area. When the predetermined area is within the effective illumination area, the radiating element is turned on. When the predetermined area is not within the effective illumination area, the radiating element is not turned on (e.g., turned off by default). In this way, the electro-optical device can map its light to a desired location without the need for any moving parts.

[0013] In an embodiment, the radiation unit is adapted to project the radiation beam in a first direction. The radiation control unit may be adapted to adjust the first direction and / or the divergence angle of the radiation beam in response to an input from the detection unit so as to adjust the radiation pattern of the radiation beam. This enables a simple implementation, allowing the direction of the radiation beam to be simply changed when a user or user movement is detected.

[0014] The first direction of the radiation beam may refer to the direction of the nominal centerline of the beam. The divergence angle of the radiation beam may refer to the angle between two directions where the intensity measured in a plane passing through the nominal beam centerline is 50% of the maximum intensity (sometimes referred to as the full angle at half power (FAHP)). For beams that do not have rotational symmetry, the beam angles are typically given for two 90-degree planes, referred to as the maximum angle and the minimum angle. In the context of the present application, the divergence angle refers to the minimum angle in this case. Note that according to the present invention, the radiation pattern may include emitting radiation beams in multiple directions toward multiple predetermined areas (for example, in the case of multiple users). In this case, the divergence angle may be independent in each direction.

[0015] In an embodiment, the radiation unit comprises an optical element comprising one or more lenses and / or one or more mirrors and / or one or more diffractive optical elements, and wherein the radiation control unit is adapted to move and / or rotate a portion of the optical element to adjust a first direction of the radiation beam.

[0016] The radiating unit may be driven by a drive current, and the radiation control unit may be adapted to adjust the pulse width and / or frequency and / or amplitude of the drive current in response to input from the detection unit so as to adjust the radiation pattern of the radiation beam. In the multi-element transmitter discussed above, the adjustment may be adjusted at the level of the individual radiating elements.

[0017] In an embodiment, the radiation unit comprises a plurality of radiation elements, each radiation element being driven by a driving current, and wherein the radiation control unit is adapted to adjust the driving current of each radiation element in response to an input from the detection unit to adjust a radiation pattern of the radiation beam. In this way, the radiation pattern can be adjusted without relying on moving or rotating one or more optical elements.

[0018] In an embodiment, the radiation unit comprises a plurality of LEDs, and the radiation control unit is adapted to: in response to an input from the detection unit, switch a subset of the plurality of LEDs on or off so as to adjust the radiation pattern of the radiation beam. This enables switching a subset of the plurality of LEDs on and off based on detection of a predetermined area. Each subset of LEDs may comprise one or more LEDs, and different subsets may comprise different numbers of LEDs.

[0019] Additionally or alternatively, the radiation unit may comprise a vertical cavity surface emitting laser (VCSEL) array having one or more radiation elements, each radiation element having an effective illumination area, wherein, for each radiation element, the radiation control unit is adapted to: switch on the radiation element when the predetermined area is within the effective illumination area, and not switch on the radiation element when the predetermined area is not within the effective illumination area. Compared to LEDs, VCSEL arrays have the advantage of providing narrower beam angles, thereby allowing the radiation energy to be concentrated on a useful area at a greater distance. Additional flexibility may also be achieved by moving and / or rotating one or more deflection members (e.g., reflectors or (micro) lenses) integrated in the VCSEL array, which may serve as (partially or fully) the above-mentioned optical element.

[0020] In an embodiment, the detection unit is adapted to determine the distance between the electro-optical device and the predetermined area and to generate an output according to the distance, and the radiation control unit is adapted to react to the detection unit according to the output of the detection unit. The distance may be determined based on a dedicated distance sensor or may be estimated based on the detected size of the predetermined area. This allows, on the one hand, to generate a sufficient PBM response when the user is close enough to the electro-optical device and, on the other hand, to achieve eye safety when the user is too close to the electro-optical device.

[0021] Using one or more of the measures discussed above, alone or in combination, different degrees of flexibility in adjusting the radiation pattern can be achieved. This enables a wide range of PBM applications accessible to users in their daily lives.

[0022] The radiation unit may be adapted to: emit a pulsed radiation beam with a peak emission wavelength between 610-1400 nm. In an embodiment, the peak emission wavelength is in the (near) infrared ((N)IR) region, for example 700-1400 nm. In an embodiment, the range may be 760-1400 nm or 800-1100 nm. Another option is the range 800-870 nm. The peak emission wavelength may also have a spectrum of red light, for example in the range 610-700 nm. Irradiating a predetermined area (e.g., a user's face) with radiation in these spectra may induce a beneficial PBM response. Some embodiments may utilize devices that emit in different wavelength ranges simultaneously.

[0023] It is generally believed that the irradiation intensity at the skin surface needs to be greater than 0.1mW / cm 2 According to an embodiment of the present invention, the electro-optical device is designed to direct the radiation beam to a predetermined area using a radiation control unit so that the radiation beam has a power higher than 0.1 mW / cm at the body surface of the user in the predetermined area. 2 , preferably higher than 1mW / cm 2 This makes it possible to efficiently induce the PBM effect in a predetermined area.

[0024] In an embodiment, the electro-optical device is adapted to be placed on a table or desk. For example, the electro-optical device may be embodied in a table attachment that emits the radiation beam. A table or desk is an ideal location for placing the PBM device because it has well-defined dimensions, whereby the distance between the PBM device and the user is predictable. This enables the radiation element of the electro-optical device (e.g., the transmission power of the radiation beam, etc.) to be designed according to typical table / desk dimensions. In this way, a reliable and efficient PBM response may be achieved in a simple and reliable manner.

[0025] Such a table accessory may or may not have any other electrical function (e.g. a general lighting function or a display function). The electro-optical device may be arranged as a "PBM gadget" which is placed on a table and is used solely or primarily for PBM purposes (the device may include additional non-electrical functions, such as serving as a pencil holder). For example, in the absence of a general lighting function, and therefore without a lamp pole and lamp head in front of the user, these objects may be placed much closer to the user. This relatively short distance enables a relatively large radiation intensity to be obtained in a predetermined area, thereby allowing the desired dose level to be achieved more quickly.

[0026] In embodiments, the electro-optical device is mounted on a ceiling or wall and / or incorporated into a portable user device (e.g., a smartphone) and / or a display device (e.g., a television). In addition, these embodiments allow the electro-optical device to incorporate one or more radiation pattern adjustment measures to utilize typical distances between such devices and users to reliably induce a PBM effect.

[0027] In an embodiment, the electro-optical device is incorporated into a general lighting device, wherein the radiation unit is adapted to project a radiation beam at a diffusion angle within 2×30°, preferably within 2×25°, more preferably within 2×20°, more preferably within 2×15°, and more preferably within 2×10°. As discussed above in the background, the idea of ​​incorporating a PBM device into a general lighting device is known. However, utilizing the radiation pattern adjustment capability of the present invention and the relatively large typical distance between the lighting device and the user, a specific narrow diffusion angle of the radiation beam (e.g., 2×10°) can be adopted. Using such a narrow beam, both energy usage efficiency and dose accumulation efficiency can be obtained.

[0028] More generally, in an electro-optical device according to the present invention (not limited to general lighting devices), the radiation unit can be adapted to project a radiation beam around a central beam line with a divergence angle (or FAHP) within + / -30°, preferably within + / -25°, more preferably within + / -20°, more preferably within + / -15°, more preferably within + / -10° or less.

[0029] The electro-optical device may further comprise a timer which is activated in response to an input from the detection unit, and the radiation control unit is adapted to stop emitting the radiation beam from the radiation unit once the timer expires. The radiation control unit may be adapted to set the timer according to a predetermined expiration time, or to set the timer so that the timer expires when a predetermined dose level (e.g., in the range 0.01-50 J / cm2) in a predetermined area is exceeded. 2 Within, preferably in the range of 0.1-20J / cm 2 More preferably, in the range of 1-10 J / cm 2 More preferably, in the range of 4-7 J / cm 2 This enables efficient dosage control. In addition, combined with the measures discussed below, personalized dosage control for each user can be achieved.

[0030] The detection unit may be adapted to detect a plurality of predetermined areas corresponding to a plurality of users. This allows the electro-optical device to direct the radiation beam towards a plurality of users sequentially or simultaneously.

[0031] In a preferred embodiment, the detection unit is adapted to: identify and distinguish individual users (e.g., using facial recognition or similar methods to determine the user's identity), and for each identified user, the radiation control unit is adapted to: direct the radiation beam to predetermined areas of the user's body by adjusting the radiation pattern so that in each predetermined area of ​​each user, the radiation beam has a power higher than 0.1 mW / cm 2 , preferably higher than 1mW / cm 2 The peak illumination intensity of a radiation beam (at the same time or at different times) can be determined. This enables the electro-optical device to induce a PBM response on multiple users, and makes it possible to control the dose of each user individually. By identifying a specific user, the electro-optical device can easily track each user even if the user moves or exchanges positions. This also makes it possible to reliably adjust the dose for each specific user. The illumination intensity over a predetermined area can be generally uniform, or can vary to some extent across the area. In the latter case, a specific value of the radiation intensity can be measured at the center of the radiation beam (e.g., at the center of the predetermined area). Similarly, the cumulative dose can be derived in the same way.

[0032] In an embodiment, for each identified user, the electro-optical device is adapted to start a timer when the detection unit identifies the user, and the radiation control unit is adapted to adjust the radiation pattern on a user-by-user basis upon expiration of each individual timer. For example, when a timer for a particular user expires (indicating that the user in question has obtained a cumulative dose level, e.g. in the range 0.01-50 J / cm 2 Within, preferably in the range of 0.1-20J / cm 2 More preferably, in the range of 1-10 J / cm 2 More preferably in the range of 4-7 J / cm 2 ), the radiation control unit can stop directing the radiation beam towards the specific user.

[0033] In an embodiment, for each identified user, the radiation control unit is adapted to pause the corresponding timer when the user is no longer identified (e.g. when the user leaves the room, is temporarily blocked or moves too far away), and resume the timer when the user is identified again. Since the electro-optical device identifies each specific user, this enables the electro-optical device to maintain the cumulative dose level for each user, even if a user temporarily disappears and reappears. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Embodiments will now be described, by way of example only, with reference to the accompanying drawings, wherein corresponding reference numerals indicate corresponding parts, and in which:

[0035] Figure 1A and Figure 1B An embodiment of an electro-optical device 1 according to the invention is schematically shown.

[0036] FIG. 2A to FIG. 2D Various arrangements are schematically shown in which the electro-optical device 1 according to the invention can be implemented.

[0037] FIG. 3A to FIG. 3D An embodiment of controlling the radiation pattern using optical means is schematically shown.

[0038] FIG. 4A to FIG. 4C An embodiment of controlling the radiation pattern by controlling the radiation source is schematically shown.

[0039] Figure 5 An embodiment of an electro-optical device 1 according to the invention is schematically shown, comprising a timer for dose control.

[0040] Figure 6 An embodiment in which the electro-optical device 1 is capable of identifying and distinguishing individual users is schematically shown. DETAILED DESCRIPTION

[0041] The following is a description of certain embodiments of the invention, given by way of example only and with reference to the accompanying drawings.

[0042] Figure 1A An embodiment of an electro-optical device 1 according to the invention is shown. The device 1 may comprise a radiation unit 10 for emitting a radiation beam 11 , a detection unit 20 for detecting a region of interest and a radiation control unit 30 for receiving input from the detection unit 20 .

[0043] The detection unit 20 is used to detect a predetermined area of ​​the user's body. The predetermined area may be any part of the user's body. In a preferred embodiment, the predetermined area covers at least a portion of the user's face, such as Figure 1A shown.

[0044] Facial detection or recognition is a type of object detection that is widely used in the fields of smartphones, security systems, photography, video conferencing, lip reading, etc. One approach relies on constructing a feature vector based on the size and position of detected features such as eyes, mouth and nose. For facial recognition, facial features are not only detected and recognized as general facial features, but also the facial features of a specific person are identified, for example by determining their specific size and (relative) position and comparing these to a reference image. The present invention can be implemented using either facial detection or facial recognition, the latter being advantageous when multiple users are involved or for personal dose control.

[0045] There are various well-known techniques for facial detection or recognition. Examples are traditional image analysis using visible light images and / or (N)IR images, human identification at a distance (HID), 3D facial recognition, thermal images, etc. The present invention may be implemented using any of these techniques, a combination of these techniques, or any other technique that can detect or recognize a user's face.

[0046] There is another advantage of using facial detection or recognition in embodiments of the present invention. The skin of the face is usually not covered by clothes and is relatively large (the average surface area of ​​a male face is 1323 cm 2 By directing the radiation beam 11 towards at least a portion of the user's face, a PBM effect can be induced in this relatively large and stable area. This improves the efficiency of the PBM device.

[0047] In this way, well-known detection methods (e.g., face detection) can be utilized to give useful information about the relative position between the device and the user, such as the direction and / or distance from the device to the user. Figure 1A As shown, using such information, the electro-optical device can direct the radiation beam to a predetermined area in a directional and / or focused manner, thereby reducing unnecessary radiation outside the predetermined area. This can be achieved by placing the electro-optical device 1 at a designed position, combined with a designed beam angle (e.g., a full angle at half power (FAHP) within 2×30°, 2×25°, 2×20°, 2×15° or 2×10°, depending on the designed position of the electro-optical device 1), and / or by adjusting the radiation pattern of the radiation beam 11 as described below.

[0048] The radiation control unit 30 may be adapted to control the radiation unit to adaptively adjust a radiation pattern (eg beam direction, beam angle, focus or a combination of these) of the radiation beam according to input from the detection unit. Figure 1B An embodiment is shown in FIG.

[0049] like Figure 1B As shown, when the user moves (e.g., stands up from their chair), the radiation pattern is adjusted to direct the radiation beam 11 to a new position of the predetermined area (e.g., the face). The radiation pattern can be adjusted by adjusting the beam direction (as shown) or in another way (e.g., by changing the spread angle, focus, etc., see below FIG. 3A to FIG. 3D and FIG. 4A to FIG. 4C ) to adjust the radiation pattern.

[0050] In an embodiment, the detection unit is adapted to determine the distance between the electro-optical device and the predetermined area and to generate an output according to the distance, and the radiation control unit is adapted to react to the detection unit according to the output of the detection unit. The distance may be determined based on a dedicated distance sensor (not shown), or the distance may be determined using the detection unit 20. For example, the detection unit 20 may estimate the size of the predetermined area and estimate the distance based on the estimation.

[0051] The radiation unit may be adapted to emit a radiation beam having a peak emission wavelength between 610-1400 nm. In an embodiment, the peak emission wavelength is in the (near) infrared ((N)IR) region, for example 700-1400 nm. In an embodiment, the range may be 760-1400 nm or 800-1100 nm. Another option is the range 800-870 nm. The peak emission wavelength may also have a spectrum of red light, for example in the range 610-700 nm. Recent advances in medical research have shown that irradiating an organism with red light radiation including the (N)IR spectrum and / or at specific energy / power levels can induce beneficial biological or biochemical reactions. Such irradiation is generally referred to as photobiomodulation (PBM). Available medical research results on the medical benefits of using PBM therapy to treat physiological and psychological symptoms are rapidly increasing. Some wavelengths of particular interest include 606, 627, 630, 632.8, 640, 660, and 670 nm (in the red region) and 785, 800, 804, 808, 810, 820, 830, 850, 904, 980, and 1060 nm (in the NIR region). Some spectral ranges of particular interest include 650-680 and 800-870 nm. The radiation unit may be configured to emit radiation in multiple wavelength regions simultaneously.

[0052] The radiation beam 11 may be pulsed, as described in WO 2020 / 119965 and WO 2021 / 099642. Replacing a constant or near-constant signal with a pulse may increase the peak radiation power emitted by the light source while consuming the same amount of electrical power. In other words, a light source with pulsed emission may achieve a much higher peak radiation power than the same device with continuous wave (CW) emission. It is generally believed that an irradiation intensity greater than 0.1 mW / cm2 at the skin surface is required. 2 According to an embodiment of the present invention, the electro-optical device is designed to: use a radiation control unit to direct the radiation beam to a predetermined area, so that the radiation beam has a power higher than 0.1 mW / cm at the surface of the user's body in the predetermined area. 2 , preferably 1mW / cm 2 or greater peak irradiation intensity, which can efficiently induce the PBM effect and enable the desired dose level (e.g., 0.01-50 J / cm2 , preferably in the range of 0.1-20 J / cm 2 More preferably, in the range of 1-10 J / cm 2 More preferably, in the range of 4-7 J / cm 2 Inside).

[0053] FIG. 2A to FIG. 2D Various examples of how an electro-optical device 1 according to the invention can be applied are shown. Such a device can include the Figure 1A and Figure 1B The measures described.

[0054] Figure 2A An embodiment is shown where the electro-optical device 1 is designed to be placed on a table 201 (or stand) (e.g., in the form of a table attachment). The table (or stand) has well-defined dimensions. This makes it an ideal place to place a PBM device, as these dimensions set boundaries for the distance between the electro-optical device 1 and the user. Taking these dimensions into account, this makes it possible to design the characteristics of the radiation beam 11 (e.g., divergence angle, etc.) so that the width of the radiation beam 11 is just enough to cover the predetermined area, with sufficient power to induce the PBM effect.

[0055] Many people have objects on their desks (eg pencil cases, speakers, etc.). These objects are suitable for incorporating the electro-optical device 1. Most of these objects are placed relatively close to the user, making them suitable for embodying PBM functionality.

[0056] Figure 2B An embodiment is shown in which the electro-optical device 1 is embodied in a computer display 202. Figure 2A , this embodiment enables the electro-optical device 1 to be designed with typical dimensions of a table 201 (or desk) such that the transmission power of the radiation beam is sufficiently high to induce a PBM response during the intended use, taking into account the propagation of the radiation beam 11. In the embodiment shown, the radiation beam 11 is focused on the user's face (rather than being diffuse), which allows for efficient use of the energy of the radiation beam to induce the PBM effect. As part of the adjustment of the radiation pattern, the focus (and / or beam direction) can be adjusted when the user moves further or closer. Similarly, the electro-optical device 1 can be embodied in a television set (not shown), wherein it can be assumed that the user is sitting at a certain distance away. In addition, the radiating unit can be incorporated into a separate device mounted on or near a computer monitor or television set.

[0057] Figure 2CAn embodiment is shown in which the electro-optical device 1 is incorporated into a portable user device (e.g., a smartphone). This embodiment has several advantages. First, the facial detection / recognition function is usually already implemented in such a device, which reduces the cost of implementing the invention. In addition, many users use the screen time of such a device for relatively long periods of time and maintain a relatively short and stable distance from the screen (e.g., 30 cm). This makes such a portable device an ideal device for providing a PBM effect.

[0058] Figure 2D An embodiment is shown in which the electro-optical device 1 is incorporated into a general lighting device 203. In the embodiment shown, the general lighting device 203 is mounted on a ceiling 204. It can also be mounted on a wall, or on a stand-alone lamp, or on any other lamp arrangement.

[0059] In addition to the radiation beam 11, the general lighting device 203 also emits visible light 213 for general lighting purposes, as described in WO2020 / 119965 and WO 2021 / 099642. Compared with the prior art, the present invention allows the radiation beam 11 to be much more directional and / or focused. Preferably, the radiation beam 11 has a diffusion angle within 2×30°, preferably within 2×25°, more preferably within 2×20°, more preferably within 2×15°, and more preferably within 2×10°. It can be seen that while the visible light 213 is diffused at a wide angle for general lighting purposes, the radiation beam 11 is projected onto a predetermined area (e.g., the user's face) so as to induce a PBM effect in that area. This allows energy saving and optimal dosage. The better the delivery of the radiation beam 11 is controlled, the less energy is "lost", so that the user receives the right amount of accurate PBM radiation.

[0060] The following table shows simulation results reflecting this advantage over the comparative example. The embodiment and the comparative example use the same pulse conditions (current, frequency, pulse width, duty cycle) for the radiation beam, while using a significantly narrower beam angle in the embodiment, and therefore a significantly narrower illumination area. In the simulated embodiment, the illumination area is barely larger than the average surface area of ​​a male face (1323 cm 2 ; Reference: Jayasekara et al. Forensic Med. Anat. Res. 2016). Therefore, most of the radiation energy is accumulated in the predetermined area, and accordingly, 6.3 Jcm 2 The time required for cumulative dosing of the embodiment is significantly shortened (1.2 hours vs. more than 8 hours), and significantly fewer LEDs can be used. Therefore, the amount of energy required in the embodiment is significantly reduced.

[0061]

[0062] Radiation pattern adjustment

[0063] FIG. 3A to FIG. 3D Several embodiments of controlling the radiation pattern using an optical element 10b are shown. These measures can be implemented in the electro-optical device 1 in Figs. 1-2.

[0064] In these embodiments, the radiation unit 10 includes a radiation source 10a and may optionally include an optical element 10b. The optical element 10b may include one or more lenses ( Figure 3A ), one or more reflectors ( Figure 3B ), one or more diffractive optical elements (DOE) ( Figure 3C ) or a combination of these. For example, one or more lenses and one or more reflectors can be combined to utilize total internal reflection ( Figure 3D ). Other combinations are possible, including combinations of the same type of deflection elements (e.g., two or more lenses, two or more mirrors, two or more DOEs). The radiation pattern can be adjusted by moving and / or rotating a portion of the optical element, such as moving one lens / mirror / DOE while maintaining the position of another lens / mirror / DOE.

[0065] In this way, the propagation of the radiation beam 11 may be adjusted in various ways. For example, the radiation control unit 30 may be adapted to adjust the direction (along the centre line "c") and / or the divergence angle and / or the focus of the beam in response to input from the detection unit.

[0066] Alternatively or additionally, the radiation pattern may be adjusted by changing the radiation emitted from the radiation source 10a, such as Figure 4A and Figure 4B As shown, this can be achieved in the embodiments discussed above.

[0067] like Figure 4AAs shown, a multi-element transmitter can be used. In the embodiment shown, the radiation source 10a of the radiation unit 10 includes a plurality of radiation elements 410, 411, 412, each of which is driven by a driving current. Although only three radiation elements are shown in the figure, any other number of radiation elements can be implemented. In this embodiment, the radiation control unit 30 (not shown in FIG. 4) is adapted to: in response to an input from a detection unit, adjust the driving current of each radiation element so as to adjust the radiation pattern of the radiation beam 11 (in this embodiment, the radiation beam 11 is a collection of radiation 110, 111, 112 from each radiation element 410, 411, 412). Each radiation element in the multi-element transmitter can be arranged to be mapped to an effective illumination area. For example, when a predetermined area is within the effective area, the radiation element is turned on; when the predetermined area is not within the effective area, the radiation element is not turned on (for example, turned off by default). This enables the electro-optical device to project the radiation beam 11 to a desired position without the need for any moving parts.

[0068] In an embodiment, the radiation unit comprises a plurality of LEDs, and the radiation control unit is adapted to: in response to an input from the detection unit, switch a subset of the plurality of LEDs on or off so as to adjust the radiation pattern of the radiation beam. This enables switching a subset of the plurality of LEDs on and off based on detection of a predetermined area. Each subset of LEDs may comprise one or more LEDs, and different subsets may comprise different numbers of LEDs. Different subsets of LEDs may be used to project radiation beams to different users.

[0069] VCSEL arrays (vertical cavity surface emitting laser arrays) are another suitable option. Compared with LEDs, VCSEL arrays have the advantage that the radiation beam they provide is relatively narrow. For example, II-VI's commercial VCSEL array product APS6401010002 can produce a beam at 25 degrees.

[0070] A VCSEL array typically comprises a plurality of individual emitters. Each individual emitter may be provided with an integrated deflection member (e.g. a reflector or a lens) to set the beam direction. Typically, each deflection member is fixed in position but configured differently for each individual emitter so that each emitter irradiates in a predetermined direction. Individual emitters may be switched on or off so that only objects of interest (within a wide far field pattern) are irradiated. This enables these individual emitters to be switched on and off based on input from the detection unit 20.

[0071] Figure 4BAn embodiment of a radiation unit 10 using a VCSEL array comprising a plurality of emitters is shown. In the embodiment shown, the VCSEL array has a plurality of active regions 410a, 411a, 412a (typically in the form of quantum wells in a semiconductor laser diode) for generating radiation (which can be used as a radiation source 10a) and a substrate 420 forming a plurality of microlenses 410b, 411b, 412b (which can be used as (partial or complete) optical element 10b). The VCSEL array may further include a submount for accommodating the plurality of emitters. The microlenses 410b, 411b, 412b are shaped and / or positioned to direct laser radiation in a variety of different directions. In the illustrated embodiment, the microlens 411b is concentric with the corresponding active area 411a (thus, the laser radiation 111 generated by the active area 411a is not deflected), while the microlenses 410b and 412b are not concentric with the corresponding active areas 410a and 412b in different directions (thus, the laser radiation 110 and 112 generated by the active areas 410a and 412a are deflected to the designed direction). By turning the individual emitters (active areas) on and off, the radiation pattern can be controlled. In this way, no moving parts are required. Alternatively, more flexible beam control can also be achieved by moving and / or rotating the microlenses 410b, 411b, 412b in the VCSEL array relative to the active areas 410a, 411a, 412a. The array of microlenses 410b, 411b, 412b can be moved (such as Figure 4B As shown by arrow b in FIG. 4 ), by moving the array of active regions 410a, 411a, 412a (as shown in FIG. Figure 4B The microlenses 410b, 411b, 412b can also be manufactured as separate parts, for example using a so-called micromechanical system (MEMS), and these elements can be controlled separately.

[0072] For example, Figure 4C As shown, for each radiation element 410, 411, 412, the radiation control unit 30 ( Figure 4C 4 (not shown) may be adapted to turn on the radiating element when the predetermined area is within the effective area, and not turn on the radiating element when the predetermined area is not within the effective area. In the illustrated embodiment, because the predetermined area (the user's face) falls outside the illumination area of ​​radiating element 412, the element is turned off. The predetermined area falls within the illumination area of ​​radiating elements 410, 411, so these elements are turned on. Note that for simplicity, the schematic diagram shows only three radiating elements. In practice, an LED or VCSEL array contains many more radiating elements.

[0073] Multi-user handling and individual dose control

[0074] Figure 5An embodiment is shown in which the electro-optical device 1 further comprises a timer 40. This embodiment may comprise one or more of the measures described above in the context of Figs. 1-4.

[0075] Studies have shown that the benefits of PBM effects vary depending on the cumulative dose per day. When the cumulative dose is too small, the benefits are negligible. When the cumulative dose is too large, the beneficial PBM effects will also deteriorate and may even cause harm. Therefore, it is preferred to control the daily cumulative dose within a certain amount (e.g., 0.01-50 J / cm 2 , preferably in the range of 0.1-20 J / cm 2 More preferably, in the range of 1-10 J / cm 2 More preferably in the range of 4-7 J / cm 2 Inside).

[0076] In accordance with this, the timer 40 may be started in response to an input from the detection unit 20. For example, when the detection unit 20 detects or recognizes a face, it may instruct the timer 40, or instruct the radiation control unit 30 to start the timer. Once the timer expires, it indicates that a sufficient amount of dose level (e.g., 0.01-50 J / cm2) has been accumulated within one day. 2 ), the radiation control unit 30 then stops the irradiation of the radiation beam 11 from the radiation unit 10. The timer 40 may be set according to a predetermined expiration time (e.g., two hours), or the timer is set to expire when a predetermined dose level (e.g., 0.01-50 J / cm 2 ) after the expiration of the term.

[0077] Figure 6 An embodiment of an electro-optical device 1 is shown in which the user-by-user Figure 5 Dosage control as described in .

[0078] In this embodiment, the detection unit is adapted to: identify and distinguish individual users (e.g., using facial recognition instead of facial detection). The radiation pattern is such that the radiation beam 11 is directed to all users individually. In the embodiment shown, the radiation beam 11 comprises a plurality of beamlets 11a and 11b, each beamlet being directed to a predetermined area (e.g., a face) of an identified user. The same applies when there are more than two users, in which case there are more than two beamlets. Alternatively or additionally, the radiation beam 11 may be directed to the radiation control unit 30 ( Figure 6 In this way, for each user, a power of more than 0.1 mW / cm in a predetermined area can be achieved at the same time or at different times. 2 , preferably higher than 1mW / cm 2By adding face detection to facial recognition in this embodiment, the electro-optical device can easily track each user even if the user happens to move or change positions.

[0079] For each individual user, the electro-optical device 1 may start a timer when the detection unit 20 recognizes the user, and the radiation control unit 30 may adjust the radiation pattern when each individual timer expires so that the radiation beam 11 is no longer directed to the user whose cumulative dose has exceeded a certain threshold. Figure 6 In the illustrated embodiment, when the left user has obtained a cumulative dose exceeding a threshold, the radiation control unit 30 may turn off the small beam 11 a (eg, by turning off a corresponding LED or VCSEL emitter, etc.).

[0080] The radiation control unit can also pause the corresponding timer when the user is no longer recognized (for example, when the user leaves the room, is temporarily blocked, or moves too far), and resume the timer when the user is recognized again. Since the electro-optical device 1 recognizes each specific user (using facial recognition in this embodiment), this enables the electro-optical device to maintain accurate dose control without interruption due to some users happening to disappear for a period of time during operation.

[0081] exist Figure 6 In the illustrated embodiment, the electro-optical device 1 is incorporated into a general lighting device, but this embodiment is equally applicable to any embodiment of the electro-optical device 1 described above, such as the above-described desktop monitor or television.

[0082] Some of the above embodiments involve logical operations or calculations. These can be implemented using software (e.g., code embodied on a machine-readable medium or in a transmission signal), hardware, or a combination of these. In a software implementation, one or more processors can be used. A hardware implementation can involve the use of a dedicated circuit system or logic configured to perform a specific operation. For example, a hardware module can be a programmable logic device, such as a field programmable gate array (FPGA) or an ASIC. It will be understood that the decision to implement using software, hardware, or a combination of these can be driven by cost and time considerations.

[0083] The above description is intended to be illustrative rather than limiting. It will be apparent to those skilled in the art that alternative and equivalent embodiments of the present invention may be conceived and put into practice without departing from the scope of the appended claims.

Claims

1. An electro-optical device (1), comprising: A radiation unit (10) adapted to: emit a radiation beam (11) having a peak emission wavelength between 610 and 1400 nm; A detection unit (20) adapted to: detect a predetermined area of ​​a user's body; and A radiation control unit (30) is used to: receive input from the detection unit, The electro-optical device (1) is adapted to: use the radiation control unit (30) to direct the radiation beam (11) toward the predetermined area, so that the radiation beam has a power higher than 0.1 mW / cm at the surface of the user's body in the predetermined area. 2 The peak irradiation intensity.

2. The electro-optical device (1) according to claim 1, wherein: The radiation control unit (30) is adapted to: The radiation unit is controlled to adaptively adjust the radiation pattern of the radiation beam (11) according to the input from the detection unit.

3. The electro-optical device (1) according to claim 1 or 2, wherein: The predetermined area substantially covers the entire face of the user, including the eyes, mouth and nose of the user.

4. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit (10) is adapted to: project the radiation beam (11) in a first direction, and The radiation control unit is adapted to adjust the first direction and / or the divergence angle of the radiation beam in response to input from the detection unit so as to adjust the radiation pattern of the radiation beam (11).

5. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit (10) comprises an optical element (10b), wherein the optical element (10b) comprises one or more lenses and / or one or more reflectors and / or one or more diffractive optical elements, and The radiation control unit (30) is adapted to move and / or rotate a portion of the optical element to adjust the first direction of the radiation beam.

6. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit (10) comprises a plurality of radiation elements (410, 411, 412), each radiation element being driven by a driving current, and The radiation control unit is adapted to adjust the driving current of each radiation element in response to the input from the detection unit so as to adjust the radiation pattern of the radiation beam (11).

7. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit includes a plurality of LEDs, and The radiation control unit is adapted to switch a subset of the plurality of LEDs on or off in response to input from the detection unit to adjust a radiation pattern of the radiation beam (11).

8. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit comprises a vertical cavity surface emitting laser (VCSEL) array having one or more radiation elements, each radiation element having an effective illumination area, Wherein, for each radiation element, the radiation control unit (30) is adapted to: When the predetermined area is within the effective lighting area, the radiation element is turned on, and when the predetermined area is not within the effective lighting area, the radiation element is not turned on.

9. An electro-optical device (1) according to any one of the preceding claims, wherein: The detection unit is adapted to: determine the distance between the electro-optical device (1) and the predetermined area, generate an output according to the distance, and The radiation control unit is adapted to react to the detection unit according to the output of the detection unit (20).

10. An electro-optical device (1) according to any one of the preceding claims, wherein: The electro-optical device is suitable for being placed on a table or a desk.

11. An electro-optical device (1) according to any one of the preceding claims, wherein: The electro-optical device (1) is mounted on a ceiling or a wall, and / or Therein, the electro-optical device is incorporated into a portable user equipment and / or a display device.

12. An electro-optical device (1) according to any one of the preceding claims, wherein: The electro-optical device is incorporated into a general lighting device, Wherein, the radiation unit is suitable for projecting a radiation beam with a diffusion angle within 2×30°, preferably within 2×25°, more preferably within 2×20°, more preferably within 2×15°, and more preferably within 2×10°.

13. An electro-optical device (1) according to any one of the preceding claims, wherein: The radiation unit is suitable for: The radiation beam is projected about the central beam line with a divergence angle within + / -30°, preferably within + / -25°, more preferably within + / -20°, more preferably within + / -15°, more preferably within + / -10°.

14. An electro-optical device (1) according to any one of the preceding claims, wherein: The detection unit is adapted to: identify and distinguish individual users, and For each identified user, the radiation control unit is adapted to: By adjusting the radiation pattern, the radiation beam is directed to predetermined areas in the user's body, so that in each predetermined area of ​​each user, the radiation beam has a power higher than 0.1 mW / cm 2 The peak irradiation intensity.

15. The electro-optical device (1) according to claim 14, wherein: For each identified user, The electro-optical device is adapted to start a timer when the detection unit recognizes a user, and The radiation control unit is adapted to adjust the radiation pattern on a user-by-user basis upon expiration of each individual timer.

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