Multi-channel optical communication via waveguides

Abstract

The device implementing optical communication uses a waveguide to efficiently collect wavelength-specific light for optical communication and propagate the collected light to a sensor. More particularly, light including multiple wavelengths and collected from one or more inlets propagates along a TIR waveguide until disturbed by a scattering element, which effectively guides the propagated light to one or more sensors. Each sensor detects a subset of multiple wavelengths. In doing so, for example, by providing light collected from multiple different locations to a single sensor, the solution proposed herein increases the amount of light available for optical communication and / or reduces the number of sensors required for optical communication. The waveguide solution proposed herein can be implemented inside the device and / or along the outer surface of the device (e.g., a housing or cover).

Description

Background Art

[0001] WiFi is a wireless technology that uses electromagnetic waves to wirelessly connect multiple devices within a specific area to each other and / or to connect one or more wireless devices within a specific area to the Internet. While WiFi has been very useful and popular in recent years, it is expected that the demand for more bandwidth will soon lead to alternative wireless technologies replacing or supplementing WiFi.

[0002] Light Fidelity (LiFi), which uses light within a specific wavelength range for local wireless communication, represents an alternative wireless technology that can replace or supplement WiFi. LiFi systems rely on visible, infrared, and / or near-ultraviolet spectrum waves. By modulating a light source (e.g., a light emitting diode), a LiFi transmitter sends a high-speed signal that is detectable by a photodetector. The photodetector converts the detected light into an electric current, which is further processed by a receiver to interpret the detected light.

[0003] The visible light spectrum is ~10,000 times larger than the radio frequency spectrum. Thus, LiFi is expected to increase bandwidth achievable by WiFi alone by a factor of 100. Additionally, LiFi tends to be more suitable for high-density and / or high-interference environments, e.g., airplanes, office buildings, hospitals, power plants, etc. As a result, there has been considerable recent interest in improving LiFi technology and / or adapting LiFi technology for specific applications and / or devices. Summary of the invention

[0004] The solution proposed herein uses a waveguide to efficiently collect light (particularly wavelength-specific light) for optical communication, and propagates the collected light to a sensor to achieve wavelength-specific detection. Such wavelength-specific light collection may involve filtering the light at the waveguide inlet to direct the wavelength-specific light to the sensor, directing the collected light to a wavelength-specific sensor, and / or filtering the light at the sensor so that the sensor detects only the desired wavelength. As used herein, "wavelength-specific" refers to one or more peak wavelengths having the maximum amplitude of a wavelength range. Thus, it will be understood that references to "wavelength-specific" typically include some number of wavelengths in addition to the peak wavelength, for example, wavelengths around each peak wavelength.

[0005] The solution proposed herein increases the amount of light available for optical communication, particularly wavelength-specific optical communication, even when the light associated with the optical communication enters the device at an angle. In addition, because multiple waveguides can guide light from multiple collection points to a single sensor, the solution proposed herein reduces the number of sensors required for optical communication. The waveguide solution proposed herein can be implemented inside a device and / or along an outer surface of a device (e.g., a housing or cover). In this way, the solution proposed herein also enables optical communication to be used in a variety of devices (e.g., cellular phones, tablet computers, smart phones, smart watches, smart glasses, etc.) and / or in a variety of scenarios.

[0006] An exemplary embodiment includes a detection system for optical communication. The detection system includes a total internal reflection (TIR) ​​waveguide and one or more light sensors. The TIR waveguide includes a first structure, a scattering element, and one or more waveguide inlets. The first structure has a first refractive index, wherein a second refractive index adjacent to the first structure is less than the first refractive index, so that light for optical communication input to the TIR waveguide propagates along the TIR waveguide within the first structure, and wherein the light includes multiple wavelengths. The scattering element is arranged at a first position of the TIR waveguide along an inner edge of the first structure, and is configured to disrupt the propagation of light along the TIR waveguide. Each of the one or more waveguide inlets is at a corresponding second position, wherein each second position deviates from the first position along the TIR waveguide. Each of the one or more waveguide inlets is configured to collect light associated with optical communication and input the collected light to the first structure at a corresponding second position. The one or more light sensors are arranged adjacent to an edge of the first structure opposite to the first position, and each light sensor is spaced from the scattering element by the thickness of the first structure. Each of the one or more light sensors detects a subset of the plurality of wavelengths of the disrupted light, wherein the subset of the plurality of wavelengths includes one or more wavelengths that total less than the plurality of wavelengths.

[0007] An exemplary embodiment includes a method for detecting light associated with optical communication. The method includes collecting light configured for optical communication via one or more waveguide inlets, wherein the one or more waveguide inlets are arranged at different first positions along a total internal reflection (TIR) ​​waveguide, the light including a plurality of wavelengths. The TIR waveguide includes a first structure having a first refractive index, wherein a second refractive index adjacent to the first structure is less than the first refractive index, so that light entering the TIR waveguide propagates along the TIR waveguide within the first structure. The method also includes disrupting the propagation of light along the TIR waveguide using a scattering element, the scattering element being arranged at a second position of the TIR waveguide along an inner edge of the first structure, wherein the second position is offset from each of the one or more first positions along the TIR waveguide. The method also includes detecting the disrupted light using one or more light sensors, wherein the one or more light sensors are arranged adjacent to an edge of the first structure opposite to the second position and are spaced apart from the scattering element by a thickness of the first structure, each of the one or more light sensors detecting a subset of the plurality of wavelengths of the disrupted light, and wherein the subset of the plurality of wavelengths includes one or more wavelengths that are less than the plurality of wavelengths in total.

[0008] According to an exemplary embodiment, the detected light is processed according to any known means to determine the information conveyed in the light collected by the detection system, and to communicate that information (when appropriate) to a user. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 An exemplary waveguide-based light detection system according to an exemplary embodiment of the solution proposed herein is shown.

[0010] Figure 2 An exemplary plurality of wavelengths suitable for use with the light detection systems disclosed herein are shown.

[0011] Figure 3A-3B A top view of an exemplary waveguide-based light detection system according to an exemplary embodiment of the solution proposed herein is shown.

[0012] Figure 4A-4B A further exemplary waveguide-based light detection system according to an exemplary embodiment of the solution proposed herein is shown.

[0013] Figure 5 A top view of another exemplary waveguide-based light detection system according to an exemplary embodiment of the solution proposed herein is shown.

[0014] Figure 6 An exemplary waveguide-based light detection system according to another exemplary embodiment of the solution proposed herein is shown.

[0015] Figure 7 An exemplary waveguide-based light detection system according to another exemplary embodiment of the solution proposed herein is shown.

[0016] Figure 8 An exemplary waveguide-based light detection system according to another exemplary embodiment of the solution proposed herein is shown.

[0017] Fig. 9 An exemplary waveguide-based light detection system according to another exemplary embodiment of the solution proposed herein is shown.

[0018] Fig.10 An exemplary method for detecting light for optical communication according to an exemplary embodiment of the solution proposed herein is shown.

[0019] Figures 11A-11C An exemplary device comprising a light detection system according to an exemplary embodiment of the solution proposed herein is shown.

[0020] Fig.12 An exemplary device comprising a light detection system according to another exemplary embodiment of the solution proposed herein is shown.

[0021] Fig.13 An exemplary device comprising a light detection system according to another exemplary embodiment of the solution proposed herein is shown. DETAILED DESCRIPTION

[0022] The use of optical communications (e.g., LiFi, together with WiFi or as an alternative to WiFi) has expanded the capabilities of local wireless communications. However, it is generally preferred that the devices used for such communications are small and have limited space available for detectors / receivers used for such communications. In addition, as the size of these devices continues to decrease and / or new features and / or hardware are constantly added to these devices, the available space in these devices is also constantly decreasing. For example, wearable devices (e.g., glasses, watches, etc.) are designed to have a minimum size to improve their wearability (e.g., making them lighter, more comfortable, etc.). The limited physical size of many devices imposes restrictions on the location and / or size and / or number of optical sensors that can be included in the device for optical communication, especially when combined with all the functions intended to be included in such a device.

[0023] Conventional solutions require a sensor for each light capture / entrance location of the device. For example, a device that implements optical communication may include three openings on the housing of the device, wherein such openings are intended or used to receive external light associated with the optical communication. In conventional solutions, such a device must include three sensors, one sensor being arranged below each of the three openings to capture light entering each opening. Because many devices have limited space available for such sensors, such conventional solutions severely limit the number of sensors that can be used for optical communication, and therefore limit the amount of light that can be collected for optical communication and / or the effectiveness of optical communication. In addition, conventional solutions often have challenging mechanical requirements regarding the location of the sensors and / or the alignment of the sensors with the corresponding openings so that the sensors can capture as much light entering the openings as possible. These mechanical limitations can severely limit the choice of locations for the openings.

[0024] The solution proposed herein solves many problems associated with conventional solutions by using waveguides to direct light from one or more openings to sensors for wavelength-specific optical communications. In doing so, the solution proposed herein reduces the number of sensors used for optical communications, enables each sensor to capture more light associated with optical communications, and / or enables flexibility in sensor size, sensor location in the device, and / or alignment of the sensor with any particular opening. In particular, the solution proposed herein enables any number of openings to be placed anywhere on the device, while also enabling one or more sensors to be placed at any suitable location within the device, which improves signal quality and reduces mechanical limitations associated with LiFi.

[0025] Figure 1 An exemplary optical detection system 100 for optical communication according to an embodiment of the solution proposed herein is shown, wherein the light used for optical communication includes multiple peak wavelengths, for example, λ 1 -λ N , for example, Figure 2 . The optical detection system 100 includes a waveguide 110 and one or more optical sensors 130. The waveguide 110 includes a total internal reflection (TIR) ​​structure 112 through which light propagates, a scattering element 114, and one or more waveguide inlets 116. The TIR structure 112 has a first refractive index n 1 , where the refractive index of the surrounding / adjacent TIR structure 112 (e.g., n 2 and / or 3 ) is less than the first refractive index n 1, so that light input to the waveguide 110 propagates along the waveguide 110 within the TIR structure 112. The scattering element 114 is arranged at a predetermined position of the waveguide 110 along the inner edge of the TIR structure 112 to disrupt the propagation of light along the TIR structure 112. Each of the one or more waveguide inlets 116 is at a position laterally offset from the position of the scattering element 114 along the waveguide 110, wherein each waveguide inlet 116 collects light 140 associated with optical communication and inputs the collected light 140 into the TIR structure 112 at a corresponding input position. Each of the one or more light sensors 130 detects a plurality of wavelengths λ 1 -λ N A subset of m -λ M , wherein ((Mm)+1)<N. To this end, the light sensor 130 is arranged adjacent to the inner edge of the TIR structure 112 opposite to the location of the scattering element 114, and is generally spaced apart from the scattering element 114 by the thickness t of the TIR structure 112, so that the light sensor 130 detects the wavelength-specific light disrupted by the scattering element 114. For example, each of the one or more light sensors 130 may include a photosensitive receiver (PSR) configured to detect the wavelength-specific light disrupted by the scattering element 114.

[0026] The propagation of light through the TIR structure 112 is at least partially affected by the refractive index n of the TIR structure 112. 1 One or more refractive index controls relative to the surroundings. When the material surrounding the TIR structure 112 has a lower refractive index than the TIR structure 112, the TIR structure 112 acts as a TIR layer, which allows light entering the TIR structure 112 at a TIR angle to propagate along the TIR structure 112 by total internal reflection, and thus with minimal or no loss. Although in some embodiments, the refractive index around the TIR structure 112 is the same, the solution proposed herein does not require the refractive index around the TIR structure 112 to be equal. Instead, the solution proposed herein only requires the refractive index n of the TIR structure 112 to be equal to the refractive index n of the TIR structure 112. 1 is greater than each refractive index of the surrounding materials so that light input into the TIR structure 112 propagates along the TIR structure 112 by total internal reflection.

[0027] The desired refractive index relationship between the TIR structure 112 and the surrounding structures / materials can be achieved in a variety of ways. For example, when the TIR structure 112 is a material having a first refractive index n 1 For a cylindrical tube, the second refractive index n around the tube is 2 Less than the first refractive index n 1 (n 2 <n 1) results in the expected total internal reflection in the TIR structure 112. In another example, when the TIR structure 112 is a structure having a first refractive index n 1 When the right rectangular prism is Figure 1 As shown in FIG. , the second refractive index n on one side of the TIR structure 112 2 Less than the first refractive index (n 2 <n 1 ), and a third refractive index n on the opposite side of the TIR structure 112 3 It is also smaller than the first refractive index (n 3 <n 1 ), resulting in total internal reflection in the TIR structure 112. In another example, the waveguide 110 can be implemented using a set of coatings or layers, where each layer / coating represents a different portion of the waveguide 110. In this example, one layer can represent a TIR layer (i.e., the TIR structure 112), while one or more layers surrounding the TIR layer have a lower refractive index than the TIR layer and therefore represent a "reflective" layer. Such a reflective layer can also be used as a protective layer to protect the TIR structure 112 from scratches, debris, and / or other foreign matter. Alternatively, a protective layer separate from the reflective layer can be applied between the TIR structure 112 and the reflective layer, wherein the protective layer has the same or lower refractive index as the reflective layer. The protective layer can also be used to add printed matter (e.g., text, images, etc.) that, when visible to a user of the device 200, identifies any desired information related to or about the device 200, such as a brand name, model name / number, team affiliation, school affiliation, etc.

[0028] The scattering element 114 includes any material or structure that disrupts the propagation of light within the TIR structure 112. In some embodiments, the scattering element 114 can direct the disrupted light to the sensor 130. In other embodiments, the scattering element 114 can scatter the light so that at least some of the originally propagated light is captured by the sensor 130. In one exemplary embodiment, the scattering element 114 includes a white or colored paint applied to the inner edge of the TIR structure 112 above the sensor 130. In another exemplary embodiment, the scattering element 114 is constructed by changing the material at the location of the scattering element 114 so that the location of the TIR structure 112 is no longer flat and / or smooth. For example, a machining point can be placed at the location of the scattering area 114 or the location of the scattering area 114 can be etched or roughened.

[0029] As described above, each of the one or more light sensors 130 detects a plurality of wavelengths λ 1 -λ N A subset of m -λ M, wherein ((Mm)+1)<N. The multiple wavelengths include multiple peak wavelengths suitable for optical communication, for example, 429nm, 509nm, 564nm, 611nm, 656nm, 703nm, and 753nm. Figure 2 In some embodiments, the plurality of wavelengths λ 1 -λ N Every subset λ m -λ M One peak wavelength among a plurality of peak wavelengths, or a plurality of peak wavelengths among a plurality of peak wavelengths may be included. For example, a first subset may include 429 nm, a second subset may include 509 nm and 564 nm, etc. It will be further understood that some subsets may overlap so that a particular peak wavelength is part of two or more subsets. Further, it will be understood that the subset may include additional non-peak wavelengths, for example, wavelengths around the peak wavelength, and the solutions proposed herein are described in terms of subsets of one or more peak wavelengths and / or described as wavelength-specific, where "wavelength-specific" refers to one or more peak wavelengths in a particular subset, but does not exclude the presence of other surrounding non-peak wavelengths.

[0030] Each sensor 130 of the one or more sensors 130 in the solution proposed herein can detect a specific subset of the plurality of wavelengths in any number of ways. In one exemplary solution, each sensor 130 can be wavelength specific, such that each sensor 130 is configured to detect a specific subset of the plurality of wavelengths. For example, Figure 3A-3B As shown in the top view of , one sensor for each subset of the plurality of wavelengths may be arranged opposite the scattering element 114 so that each sensor 130 detects only the corresponding peak wavelength. Figure 3A In the example, each sensor detects Figure 2 One of the peak wavelengths, for example, sensor 130 1 Detection 429nm, sensor 130 2 Detection 509nm, sensor 130 3 Detection 564nm, sensor 130 4 Detection 611nm, sensor 130 5 Detection 656nm, sensor 130 6 Detection 703nm, sensor 130 7 Detect 753nm. It will be appreciated that if there are more peak wavelengths, more sensors 130 may be used, while if there are fewer peak wavelengths to detect or if each subset includes multiple peak wavelengths, fewer sensors 130 may be used. For example, Figure 3BAn exemplary embodiment comprising four sensors is shown, wherein each of the four sensors is arranged opposite to the scattering element 114, and wherein the sensor 130 1 Detection 429nm, sensor 130 2 Detection of 509nm and 564nm, sensor 130 3 Detection of 611nm and 656nm, sensor 130 4 Detection of 703 nm and 753 nm. It will therefore be appreciated that the solution proposed herein allows for more or fewer sensors, depending on the number of wavelength subsets.

[0031] Although the figures used to illustrate embodiments of the solutions proposed herein show hexagonal sensors 130, it will be understood that the sensors 130 are not limited to a hexagonal shape. Each sensor 130 can be of any shape and / or size, wherein the shape and / or size are typically defined based on space constraints and / or manufacturer parameters. Further, the sensors 130 used in the solutions proposed herein need not all have the same size or shape. Still further, it will be understood that the solutions proposed herein do not require each sensor 130 to be adjacent to one or more of the other sensors 130, such as Figure 3A-3B As shown in ; the sensors 130 may be arranged relative to the scattering element 114 in any suitable manner so that each sensor 130 detects its corresponding subset of the plurality of wavelengths.

[0032] In another exemplary embodiment, light to each sensor 130 may first be directed to the sensor 130, for example, at the waveguide inlet 116 (eg, Figure 4A ) and / or at the location of sensor 130 (as shown in Figure 4B 14) through the wavelength specific element 117 so that the light input to the sensor 130 includes only the wavelengths in the corresponding subset. In such an exemplary embodiment, the sensor 130 for collecting the light disturbed by the scattering element 114 may also be wavelength specific or may be capable of detecting any number of wavelengths, including but not limited to the wavelengths in the corresponding subset.

[0033] Figure 4A An exemplary embodiment is shown, wherein the wavelength specific element 117 is a filter 117 arranged at the waveguide inlet 116, wherein the filter 117 is configured to make the peak wavelength λ of the specific wavelength subset m -λ M By blocking the remaining peak wavelengths in the plurality of wavelengths, m -λ M The propagates along the waveguide 110 until they are disturbed by the scattering element 114 and detected by the corresponding sensor 130. Figure 4BAs shown in FIG. 1 , the filter 117 may alternatively or additionally be arranged adjacent to the sensor 130, wherein the wavelengths captured at the waveguide inlet 116 propagate along the waveguide 110, but only a subset of wavelengths λ m -λ M The light reaches the sensor 130 and is detected by the sensor 130 .

[0034] Figure 5 Another exemplary embodiment of the solution proposed herein is shown, where the wavelength specific element 117 is a prism 117. Exemplary prisms include, but are not limited to, a dispersive prism (e.g., a refractive prism or a diffraction grating) or a reflective prism. In this embodiment, the prism 117 separates the input light into separate wavelength subsets, where each subset is input into a subset-specific waveguide 110. For example, if the input light has seven peak wavelengths λ 1 -λ N , the prism 117 can separate the input light into seven different directions, wherein each direction corresponds to one of the peak wavelengths, so that each peak wavelength is input into a separate waveguide 110 to be detected by the sensor 130. Figure 5 In the example above, this leads to 1 is input to the waveguide 110 1 Sensor 130 1 Detection, λ 2 is input to the waveguide 110 2 Sensor 130 2 Detection, λ 3 is input to the waveguide 110 3 Sensor 130 3 Detection, λ 4 is input to the waveguide 110 4 Sensor 130 4 Detection, λ 5 is input to the waveguide 110 5 Sensor 130 5 Detection, λ 6 is input to the waveguide 110 6 Sensor 130 6 Detection, λ 7 is input to the waveguide 110 7 Sensor 130 7 It will be appreciated that if there are more than seven peak wavelengths, additional waveguides 110 and sensors 130 may be used, while if there are fewer than seven peak wavelengths and / or one or more subsets include multiple peak wavelengths, fewer waveguides 110 and sensors 130 may be used. Figure 5A top view of an exemplary prism solution is shown in which the prism 117 fans out each subset in one plane, but it will be understood that the prism 117 may be configured to separate the wavelengths in any suitable manner and / or in any suitable direction, and that the solution presented herein will configure the orientation of the waveguide 110 relative to the prism 117 and the waveguide inlet 116 as appropriate so that the waveguide 110 receives the corresponding subset of wavelengths and directs them to the corresponding sensor 130.

[0035] Further details are provided below regarding how light enters the device and is directed to the sensor 130. It will be appreciated that these details apply to any individual peak wavelength, subset of peak wavelengths, and / or multiple peak wavelengths separated at some point in the detection system 100 (e.g., at the waveguide inlet 116, at the sensor 130, etc.). As such, the wavelength-specific aspects described above apply to each of the multiple openings, multiple sensors, multiple directions, light-guiding elements, etc. discussed further below.

[0036] As described above, light enters the waveguide 110 after first entering the waveguide inlet 116. Each waveguide inlet 116 includes an opening on the housing of the device 200 that is configured to collect light 140 associated with, for example, optical communications and input the collected light into the TIR structure 112 of the waveguide 110. Each waveguide inlet 116 is laterally offset from the location of the scattering element 114 / sensor 130, wherein the light 140 collected at one inlet propagates along the waveguide 110 to reach the sensor 130. In some embodiments, the waveguide inlet 116 may include only an opening. In other embodiments, the waveguide inlet 116 may include a collecting element 124, such as a lens or a lens system (e.g., Figure 7 ), wherein the collecting element 124 is configured to increase the amount of external light 140 input into the waveguide 110. When the waveguide inlet 116 includes the collecting element 124, typically the collecting element 124 will have a wide field of view (FoV) to increase the amount of light collected. Exemplary lenses include, but are not limited to, Fresnel lenses 124a ( Figure 8 )、Plano-convex lens 124b( Figure 8 ) etc. It will be appreciated that the use of any collecting element 124 in one or more waveguide inlets 116 is optional.

[0037] The waveguide 110 may also include a light guide element 118 opposite the corresponding waveguide inlet 116, which is configured to promote the propagation of light collected from the waveguide inlet 116 along the TIR structure 112. In an exemplary embodiment, the light guide element 118 includes a reflector configured to reflect the light collected by the corresponding waveguide inlet 116 at a total internal reflection angle to promote the propagation of the collected light along the TIR structure 112. An exemplary reflector includes an angled mirror 118, such as Figure 6 As shown in , it reflects the incident light at an angle θ equal to the incident angle θ. To achieve total internal reflection, this angle θ may be equal to the total internal reflection angle for waveguide 110. Additional reflectors include, but are not limited to, multiple etched surfaces (such as Figure 8 ), mirror printing or a material with a lower refractive index, so that the angle θ of the light leaving the light guide element 118 is the same as the incident angle on the light guide element 118. In another exemplary embodiment, the light guide element 118 includes a curved portion near the corresponding waveguide inlet 116, such as Figure 7 As shown in , where the curved portion is configured to direct the collected light at a total internal reflection angle to promote the propagation of the collected light along the TIR structure 112.

[0038] Figure 1 3-7 shows a single waveguide inlet 116 providing light to a single sensor 130. However, the solutions presented herein are not limited thereto. Alternative embodiments may include multiple waveguide inlets 116 that collect light to propagate to the sensor 130 along one or more corresponding waveguides 110. In some embodiments, multiple waveguide inlets 116 propagate light to a single sensor 130 using the same waveguide 110. In other embodiments, multiple waveguides 110 propagate light from one or more waveguide inlets 116 to a single sensor 130. In addition, the position of one or more waveguide inlets 116 relative to the sensor may be selected to reduce noise and / or increase signal strength. For example, the lateral spacing between multiple waveguide inlets 116 and corresponding sensors 130 may be configured so that light entering the sensor 130 is constructively increased. Alternatively or additionally, the lateral spacing between multiple waveguide inlets 116 and corresponding sensors 130 may be configured so that interference present in the collected light is destructively or neutrally increased.

[0039] Figure 8-9 An exemplary embodiment is shown having multiple waveguide inlets 116 directing light to a single sensor 130. Figure 8As shown in FIG. 1 , the optical sensor 130 can detect light originating from a plurality of waveguide inlets 116 (e.g., a first waveguide inlet 116a and a second waveguide inlet 116b located on opposite sides of the TIR waveguide 110 as viewed from the optical sensor 130). In this exemplary embodiment, the waveguide inlet 116a and the lens 124a collect light 140a, and the light guide element 118a establishes a TIR angle for the collected light to propagate 126a of the collected light along the TIR structure 112 in a first direction toward the sensor 130. In addition, the waveguide inlet 116b and the lens 124b collect light 140b, and the light guide element 118b establishes a TIR angle for the collected light to propagate 126b of the collected light along the TIR structure 112 in a second direction opposite to the first direction toward the sensor 130. The scattering element 114 disrupts the propagation 126a, 126b of the light collected by the waveguide inlets 116a, 116b from the two directions to be detected by the sensor 130.

[0040] exist Fig. 9 , the light sensor 130 detects light originating from three waveguide inlets 116a, 116b, 116c. In this exemplary embodiment, the TIR waveguide 110 includes a plurality of branches 110a, 110b, 110c, each branch propagating 126a, 126n, 126v light from a corresponding inlet 116a, 116b, 116a, respectively, toward the light sensor 130 in a different direction, wherein the scattering element 114 disrupts the propagated light to enable detection by the light sensor 130. It will be appreciated that Fig. 9 The multiple branches 110 a , 110 b , 110 c of may represent different waveguides 110 , which together guide the collected light to a single sensor 130 .

[0041] Although the exemplary detection system 100 is shown as having only one to three wavelength inlets 116, it will be understood that the detection system 100 disclosed herein may include any number of waveguide inlets 116. In general, the detection system 100 may include any number of waveguide inlets 116 and / or waveguides 110, wherein each inlet 116 is located at a location of the waveguide 110 that is laterally displaced from the sensor 130 and the scattering element 114, such that fewer sensors 130 than waveguide inlets 116 and / or waveguides 110 are used to achieve optical communication. In doing so, the solution proposed herein reduces the number of sensors 130 associated with optical communication while improving the quality of optical communication, for example, by increasing the amplitude of the detected light. In addition, by using the waveguide 110 to direct light from multiple inlets 116 to the sensor 130, the solution proposed herein relaxes the limitations previously imposed on the sensor 130, such as size, power, etc., because the sensor 130 can now be placed at any suitable location in the device 200.

[0042] Fig.10 An exemplary method 300 for detecting light associated with optical communication is shown. The method 300 includes collecting light configured for optical communication via one or more waveguide inlets 116 arranged at different first locations along a total internal reflection TIR waveguide 110 (block 310), wherein the light includes a plurality of wavelengths λ 1 -λ N The TIR waveguide 110 includes a first refractive index n 1 The TIR structure 112, wherein the second refractive index n adjacent to the TIR structure 112 2 and / or 3 Less than the first refractive index n 1 , so that light entering the TIR waveguide 110 propagates along the TIR structure 112. The method 300 also includes disrupting the propagation of light along the TIR waveguide 110 using a scattering element 114, the scattering element 114 being arranged at a second position of the TIR waveguide 110 along an inner edge of the TIR structure 112 (block 320). The second position is offset (laterally) from each of the one or more first positions along the TIR waveguide 110. The method 300 also includes detecting the disrupted light using one or more light sensors 130, the one or more light sensors 130 being arranged adjacent to an edge of the TIR structure 112 opposite the second position and spaced apart from the scattering element 114 by a thickness t of the TIR structure 112 (block 330). Each of the one or more light sensors 130 detects a plurality of wavelengths λ of the disrupted light 1 -λ N A subset of m -λ M , where the multiple wavelengths λ 1 -λ N A subset of m -λ M One or more wavelengths are included that total less than the plurality of wavelengths, ie, ((Mm)+1)<N.

[0043] As mentioned above, the light detection system 100 of the solution proposed herein can be implemented in and / or as a part of any number of wireless devices 200 that implement optical communication. The exemplary device 200 can be worn and / or carried by a user, wherein the light detection system 100 disclosed herein can be inside the housing of the device 200, partially arranged inside the device 200 and partially integrated with / arranged on the housing of the device 200, or implemented on the outer surface of the housing of the device 200.

[0044] Figures 11A-11CAn exemplary smartphone device 200 is shown. The smartphone device 200 may include a waveguide inlet 116 around the display 220 along the perimeter of the housing 210, such as Fig.11A and Fig. 11C Alternatively or additionally, the device 200 may include a waveguide inlet (eg, Fig. 11B ), and / or a waveguide inlet integrated with display 220 (as shown in Fig. 11C ). It will be appreciated that integration of the waveguide inlet 116 with the display 220 may include placing the waveguide inlet 116 below a transparent type of display 220 (e.g., an active matrix organic light emitting diode (AMOLED) screen / display). It will be further appreciated that the waveguide solution presented herein enables multiple waveguide inlets 116 to be placed at any suitable location on the smartphone device 200, in addition to those explicitly shown, while enabling a single sensor 130 (or fewer sensors 130 than there are waveguide inlets 116) to be placed at any location in the device 200 suitable for a sensor 130 to detect light from multiple inlets 116, thereby enabling optical communication.

[0045] In another exemplary embodiment, the device 200 comprises a watch, such as Fig.12 For the watch embodiment, the waveguide inlet 116 may be placed at any suitable location, for example, around the watch face 230 and / or in the watch bezel, integrated with the watch display (not shown), as part of the watch face (not shown), etc. Fig.13 In yet another exemplary embodiment shown in , the device 200 comprises glasses, wherein the waveguide inlet 116 is arranged along the frame 240 of the glasses. In addition to the implementations of smart phones, watches, and glasses discussed herein, the solutions proposed herein are also applicable to any wireless device that implements optical communication. For example, other exemplary devices 200 include, but are not limited to, hearing aids, fitness monitors, cellular phones, laptop computers, tablet computers, etc.

[0046] Of course, without departing from the essential characteristics of the invention, the present invention may be implemented in other ways different from those specifically set forth herein. The embodiments herein are considered in all respects to be illustrative and not restrictive, and all changes within the meaning and equivalent range of the appended claims are intended to be included therein.

Claims

1. A detection system for optical communication, the detection system comprising: A total internal reflection TIR waveguide comprising: a first structure having a first refractive index, wherein a second refractive index of a material portion adjacent to the first structure is less than the first refractive index, such that light for optical communication input to the TIR waveguide at one or more waveguide inlets propagates along the TIR waveguide within the first structure, the light comprising a plurality of wavelengths; a single scattering element disposed along an inner edge of the first structure at a first location of the TIR waveguide, the first location offset from a second location of each of the one or more waveguide inlets; and and a plurality of wavelength-specific light sensors disposed adjacent to an edge of the first structure opposite the first position and each of the wavelength-specific light sensors is spaced apart from the scattering element by a thickness of the first structure, wherein each of the plurality of wavelength-specific light sensors detects a different subset of the plurality of wavelengths of light disrupted by the scattering element.

2. The detection system according to claim 1, wherein: At least one of the one or more waveguide inlets comprises a wavelength specific element configured to collect wavelength specific light corresponding to a subset of the plurality of wavelengths to input the wavelength specific light into the first structure.

3. The detection system according to claim 2, wherein: The wavelength specific element includes a wavelength specific filter.

4. The detection system according to claim 2, wherein: The wavelength specific element includes a prism configured to separate the collected light so as to input the wavelength specific light into the first structure.

5. The detection system according to any one of claims 1 to 4, wherein: The scattering element comprises a white or colored paint applied to the inner edge of the first structure.

6. The detection system according to any one of claims 1 to 4, wherein: The scattering elements include machined points placed at the locations of the scattering elements, or wherein the locations of the scattering elements are etched or roughened.

7. A portable device comprising the detection system according to any one of claims 1-6.

8. The portable device according to claim 7, wherein: The portable device is a smartphone.

9. The portable device according to claim 7, wherein: The portable device is a watch or glasses wearable by a user of the portable device.

10. A method of detecting light associated with optical communications, the method comprising: collecting light configured for said optical communication via one or more waveguide inlets, said one or more waveguide inlets being arranged at one or more first locations along a total internal reflection (TIR) ​​waveguide, said light comprising a plurality of wavelengths, and said TIR waveguide comprising a first structure, said first structure having a first refractive index, wherein a second refractive index of a material portion adjacent to said first structure is less than said first refractive index, such that light entering said TIR waveguide propagates within said first structure along said TIR waveguide; disrupting propagation of the light along the TIR waveguide using a single scattering element, the scattering element being arranged along an inner edge of the first structure at a second location of the TIR waveguide that is offset from each of the one or more first locations along the TIR waveguide; and The disrupted light is detected using a plurality of wavelength-specific light sensors arranged adjacent to an edge of the first structure opposite the second position and spaced apart from the scattering element by a thickness of the first structure, wherein each of the plurality of wavelength-specific light sensors detects a different subset of the plurality of wavelengths of light disrupted by the scattering element.

11. The method according to claim 10, wherein: at least one of the one or more waveguide inlets comprises a wavelength specific element configured to collect wavelength specific light corresponding to a subset of the plurality of wavelengths; as well as The collecting the light includes: inputting the wavelength-specific light into the first structure.

12. The method according to claim 11, wherein: The wavelength specific element includes a wavelength specific filter; as well as The collecting the light includes filtering the light configured for the optical communication to input the wavelength-specific light into the first structure.

13. The method according to claim 11, wherein: The wavelength specific element includes a prism configured to separate the light configured for the optical communication into wavelength specific lights; as well as The collecting the light includes: inputting the wavelength-specific light into the first structure.

14. The method according to any one of claims 10 to 13, wherein: The scattering element comprises a white or colored paint applied to the inner edge of the first structure.

15. The method according to any one of claims 10 to 13, wherein: The scattering elements include machined points placed at the locations of the scattering elements, or wherein the locations of the scattering elements are etched or roughened.

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