Time-of-flight measurement system and electronic device

Abstract

The application discloses a time-of-flight measurement system and electronic equipment, and relates to the technical field of optical sensors. The assembly comprises a screen and a time-of-flight camera, the time-of-flight camera is arranged on one side of the screen, the time-of-flight camera comprises a transmitting end and a receiving end, the screen comprises a screen light-emitting layer and a substrate, the screen light-emitting layer is arranged on the substrate, and the screen is provided with a transmitting window and a receiving window. The infrared light emitted by the transmitting end passes through the transmitting window, the receiving end receives the infrared light passing through the receiving window, the distance between the transmitting end and the receiving end is greater than or equal to a threshold distance, and / or the substrate is provided with a light-absorbing structure. According to the application, the distance between the transmitting end and the receiving end is greater than or equal to the threshold distance, and / or the light-absorbing structure is arranged on the substrate, so that the interference of stray light on the imaging and depth calculation of the measured object is reduced, and the information acquisition accuracy of depth information is improved.

Description

Technical Field

[0001] This application relates to the field of optical sensor technology, and in particular to a time-of-flight measurement system and electronic device. Background Technology

[0002] Current mobile devices generally adopt full-screen displays for better visual effects and portability. To meet the needs of facial recognition, secure facial payment, and depth information acquisition, these devices are equipped with Time-of-Flight (TOF) cameras, which are located below the screen. The TOF camera emits near-infrared light into the scene and uses the time-of-flight or phase information of the light to measure the distance to objects in the scene. The advantages of TOF cameras include low computational cost for depth information, strong anti-interference capabilities, and a long measurement range, thus they are gradually gaining popularity.

[0003] In existing technology, the transmitter (TX) and receiver (RX) of a time-of-flight camera are both embedded below the screen, and the distance between the transmitter and receiver is a first distance. When the first distance is too small, the infrared light from the TOF transmitter will be reflected multiple times inside the multi-layer structure of the screen when it passes through the screen. This causes the image sensor (sensor) near the receiver to collect depth information that is not the actual situation, resulting in serious problems such as processing misjudgment and failure of recognition function. Summary of the Invention

[0004] This application provides a time-of-flight measurement system and electronic device. The time-of-flight measurement system can reduce the interference caused by stray light on the imaging and depth calculation of the measured object, and improve the accuracy of depth information acquisition.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] Firstly, a time-of-flight measurement system is provided, including a screen and a time-of-flight camera. The time-of-flight camera is disposed on one side of the screen and includes a transmitter and a receiver. The screen includes a screen light-emitting layer and a substrate, with the screen light-emitting layer disposed on the substrate. A transmission window and a reception window are formed on the screen. Infrared light emitted by the transmitter passes through the transmission window, and the receiver receives the infrared light passing through the reception window. The distance between the transmitter and the receiver is greater than or equal to a threshold distance, and / or an extinction structure is provided on the substrate. The threshold distance refers to the distance that reduces stray light entering the receiver through the screen light-emitting layer; the extinction structure reduces stray light entering the receiver through the screen light-emitting layer.

[0007] Based on this, infrared light is emitted from the transmitter. This infrared light passes through the emission window and reaches the object being measured, where it is reflected. The reflected infrared light is then received by the receiver through the receiving window. The distance to the object can be calculated by measuring the time of flight of the infrared light. By setting the distance between the transmitter and receiver to be greater than or equal to a threshold distance (which reduces the distance of stray light entering the receiver through the screen's emissive layer), the greater propagation distance causes the stray light to be reflected multiple times within the screen's emissive layer, thus weakening its energy and reducing the amount of stray light reaching the receiver, thereby improving the accuracy of depth information acquisition. Furthermore, by incorporating an extinction structure on the substrate, the structure can cause multiple reflections of stray light within the screen's emissive layer, consuming light energy and affecting its transmission direction. Alternatively, it can directly absorb stray light within the screen's emissive layer, reducing the amount of stray light transmitted to the receiver and minimizing interference with the imaging and depth calculation of the object being measured, further improving the accuracy of depth information acquisition.

[0008] In one possible design of the first aspect, the matting structure includes a matting film layer disposed on the side of the substrate near the screen light-emitting layer, and the matting film layer is used to absorb stray light entering the screen light-emitting layer.

[0009] Based on this, by setting the extinction structure as an extinction film layer and placing it on the side of the substrate close to the screen light-emitting layer, when stray light is transmitted within the screen light-emitting layer and reflected to the extinction film layer, the extinction film layer can absorb the stray light, thereby reducing the stray light transmitted through the screen light-emitting layer to the receiving end, reducing the interference of stray light on the imaging and depth calculation of the measured object, and improving the accuracy of depth information acquisition.

[0010] In one possible design of the first aspect, the extinction structure includes a microstructure layer disposed on the side of the substrate near the screen light-emitting layer. The microstructure layer is used to scatter and weaken stray light entering the receiver through the screen light-emitting layer.

[0011] Based on this, by setting the extinction structure as a microstructure layer and placing it on the side of the substrate close to the screen light-emitting layer, when stray light is transmitted within the screen light-emitting layer, it is reflected to the microstructure layer. The microstructure layer can scatter the stray light, so that the stray light within the screen light-emitting layer has multiple transmission directions. This reduces the stray light transmitted through the screen light-emitting layer to the receiving end, reduces the interference of stray light on the imaging and depth calculation of the measured object, and improves the accuracy of depth information acquisition.

[0012] In one possible design approach of the first aspect, the microstructure layer includes multiple structural units, the shape of which is one or more of the following: sawtooth, arc, triangle, rhombus, and stepped.

[0013] Based on this, by setting the microstructure layer to include multiple structural units, when stray light is transmitted to each structural unit, each structural unit can scatter the stray light within the screen's emissive layer, which helps to weaken the energy of the stray light. By setting the structural units to one or more of the following shapes—sawtooth, arc, triangular, rhomboid, and stepped—it is beneficial to scatter the stray light.

[0014] In one possible design approach of the first aspect, the element size of the structural unit is 0.05 μm, the thickness of the structural unit is 0.1 μm, and the interval between two adjacent structural units is 0.05 μm.

[0015] Based on this, the design approach demonstrates a specific dimensional design for structural units in a microstructure layer.

[0016] In one possible design of the first aspect, the transmitter is positioned directly below the first end of the screen, and the receiver is positioned directly below the second end of the screen.

[0017] Based on this, by placing the transmitter and receiver at opposite ends of the screen, and maintaining the maximum distance between them, it is beneficial to reduce interference from stray light and improve the accuracy of depth information acquisition.

[0018] In one possible design of the first aspect, the matte film layer is a colorless and transparent film layer, or the matte film layer is a diffuse reflection coating layer.

[0019] Based on this, by setting the matte film layer to a colorless and transparent state, the image efficiency of the screen can be guaranteed to meet conventional display requirements. Setting the matte film layer as a diffuse reflection layer is one specific implementation method in this application embodiment.

[0020] In one possible design of the first aspect, the thickness of the matting film layer is 5 μm to 70 μm.

[0021] Based on this, by setting the thickness of the matte film layer within this range, it is possible to eliminate stray light reflected from the inner layer of the screen without affecting the screen display characteristics within the interval area.

[0022] In one possible design approach of the first aspect, the matte film layer is made by spin coating, spraying, or casting.

[0023] Based on this, the design method demonstrates some specific manufacturing methods for matte film layers.

[0024] In one possible design approach of the first aspect, the microstructure layer is made by laser etching, chemical etching, sandblasting, laser atomization, or molding.

[0025] Based on this, the design approach demonstrates some specific methods for fabricating microstructure layers.

[0026] In one possible design of the first aspect, the line connecting the center of the transmitting end and the center of the transmitting window is perpendicular to the substrate, and the line connecting the center of the receiving end and the center of the receiving window is perpendicular to the substrate.

[0027] Based on this, by setting the transmitting window to correspond to the transmitting end settings and the receiving window to correspond to the receiving end settings, it is beneficial to transmit and receive infrared light. The width of the transmitting window and the receiving window can be set according to the actual situation.

[0028] Secondly, embodiments of this application provide an electronic device including the time-of-flight measurement system described in the first aspect and any possible design thereof.

[0029] Understandably, the beneficial effects that the electronic device provided by the second aspect described above can achieve can be referenced to the beneficial effects of the first aspect and any of its possible design embodiments, which will not be repeated here. Attached Figure Description

[0030] Figure 1 A structural diagram of a screen and flight camera module provided for the prior art;

[0031] Figure 2 This is a schematic diagram of an electronic device according to an embodiment of this application;

[0032] Figure 3 This is a schematic diagram of the structure of a time-of-flight measurement system provided in an embodiment of this application;

[0033] Figure 4 A schematic diagram of another time-of-flight measurement system provided in this application embodiment;

[0034] Figure 5 This application provides a schematic diagram of the structure of a screen in a time-of-flight measurement system.

[0035] Figure 6 This is a schematic diagram of another structure of the screen in a time-of-flight measurement system provided in an embodiment of this application;

[0036] Figure 7 This is another schematic diagram of the screen structure in a time-of-flight measurement system provided in an embodiment of this application.

[0037] In the figure: 11-screen light-emitting layer; 12-substrate; 13-extinction structure; 131-extinction film layer; 132-microstructure layer; 20-emitter; 30-receiver; 40-image sensor; 50-emission window; 60-receiver window; 70-object under test; 80-imaging and depth information. Detailed Implementation

[0038] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0039] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0040] In the embodiments of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature.

[0041] It should be understood that the terminology used in the description of the various examples herein is for the purpose of describing the particular examples only and is not intended to be restrictive. As used in the description of the various examples, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context explicitly indicates otherwise.

[0042] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0043] It should also be understood that the term "and / or" as used herein refers to and covers any and all possible combinations of one or more of the associated listed items. The term "and / or" describes an association between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects are in an "or" relationship.

[0044] It should also be understood that, in this application, unless otherwise expressly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a sliding connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium.

[0045] It should also be understood that the term “comprising” (also referred to as “includes”, “including”, “comprises” and / or “comprising”) as used in this specification specifies the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0046] It should be understood that the terms "an embodiment," "another embodiment," and "a possible design" used throughout the specification mean that a specific feature, structure, or characteristic related to an embodiment or implementation is included in at least one embodiment of this application. Therefore, phrases such as "in one embodiment of this application," "in another embodiment of this application," and "a possible design" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0047] To facilitate understanding of the technical solutions of this application, the technical background related to the technical solutions of this application will be introduced before writing the embodiments of this application.

[0048] refer to Figure 1 , Figure 1 This is a structural diagram of a screen and flight camera module provided by existing technology. (Example) Figure 1 As shown, in the prior art, the distance between the transmitter (TX) and receiver (RX) of a TOF transmitter is a first distance. Because this first distance is too small, from... Figure 1 As can be seen, the infrared light emitted by the transmitter TX is reflected inside the multi-layer structure of the screen when it passes through the screen. This reflected infrared light is finally received by the receiver RX of the TOF, causing the image sensor (sensor) close to the receiver RX to collect these interference signals and obtain depth information that is not in line with the actual situation. This leads to serious problems such as processing misjudgment and failure of recognition function.

[0049] To address the problems of strong interference signals and poor accuracy of depth information acquisition in existing screen and flight camera modules, leading to algorithm recognition and functional failures, this application provides a time-of-flight measurement system and electronic device. This system can discretize and eliminate stray light in the time-of-flight camera, improving the accuracy of the received signal and the precision of depth information acquisition. The following is a detailed explanation... Figures 2 to 7 The embodiments of this application will be described.

[0050] This application provides an electronic device. This electronic device includes, for example, mobile phones, tablets, smartwatches, desktop computers, laptops, handheld computers, notebook computers, ultra-mobile personal computers (UMPCs), netbooks, as well as cellular phones, personal digital assistants (PDAs), augmented reality (AR) / virtual reality (VR) devices, etc. This application does not impose any special limitations on the specific form of the above-mentioned electronic device. For ease of explanation, the following description uses a mobile phone as an example.

[0051] refer to Figure 2 , Figure 2 This is a schematic diagram of an electronic device according to an embodiment of this application. Figure 2 As shown, the electronic device is a mobile phone, in which, Figure 2 (a) is a schematic diagram of the mobile phone from the side. Figure 2 Figure (b) shows the internal structure of the mobile phone after the back cover has been removed. This electronic device mainly includes a display screen 100, a mid-frame 110, a time-of-flight camera 10, a PCB board (not shown), and a back cover 120. The display screen 100 is located on one side of the mid-frame 110, and the back cover 120 is located on the other side of the mid-frame 110, forming a closed space. The PCB board is located within the closed space between the screen 100 and the back cover 120. The time-of-flight camera 10 is mounted on the PCB board and is generally located at the top of the phone. When the display screen 100 is placed facing upwards, the time-of-flight camera 10 is located below the display screen 100.

[0052] When the time-of-flight camera 10 collects information, the received signal includes stray light. This stray light is formed by the combined influence of multiple factors, including the distance between the transmitter 20 and receiver 30 in the time-of-flight camera, and the influence of the display screen. To reduce the interference of stray light, the components formed by the display screen and the time-of-flight camera in the electronic device provided in this application embodiment are described below.

[0053] refer to Figure 3 , Figure 3 This is a schematic diagram of a time-of-flight measurement system provided in an embodiment of this application. Figure 3As shown, the structural component includes a screen and a time-of-flight camera. The time-of-flight camera is located below the screen and includes a transmitter 20 and a receiver 30. The transmitter 20 emits infrared light to the surface of the object 70 being measured. After being reflected by the object 70, the infrared light is received by the receiver 30. The distance to the object 70 is calculated by calculating the return time of the infrared beam, thereby obtaining the depth information of the object's surface.

[0054] The screen features a window structure comprising a transmitting window 50 and a receiving window 60. The transmitting window 50 corresponds to the transmitting end 20 in the time-of-flight camera, and the receiving window 60 corresponds to the receiving end 30 in the time-of-flight camera. During depth information acquisition, the transmitting end 20 in the time-of-flight camera emits infrared light, referred to as emitted light. This emitted light passes through the transmitting window 50 on the screen and reaches the object 70 outside the screen. The infrared light is reflected off the surface of the object 70, and the reflected light is called reflected light. The reflected light passes through the receiving window 60 on the screen and is received by the receiving end 30 below it. An image sensor 40 is located below the receiving end 30. The reflected light received by the receiving end 30 is transmitted to the image sensor 40, which calculates the imaging and depth information 80 corresponding to the object 70 based on the received light. Of the infrared light emitted by the transmitter 20, some of it enters the inner layer of the screen, is reflected, and is then received by the receiver 30. Since some of the light does not reflect the characteristics of the object 70 being measured, this portion of infrared light that passes through the inner layer of the screen and is received by the receiver 30 is called stray light.

[0055] It should be noted that the transmission window 50 is configured to correspond with the transmitter 20 in the time-of-flight camera. This means that the transmission window 50 is positioned near the transmitter 20 so that the infrared light emitted by the transmitter 20 can pass through the transmission window 50 to reach the object under test 70, and the intensity of the infrared light reaching the object under test 70 after passing through the transmission window 50 is sufficient for testing. Similarly, the receiving window 60 is configured to correspond with the receiver 30 in the time-of-flight camera. This means that the receiving window 60 is positioned near the receiver 30 so that the infrared light reflected by the object under test 70 can pass through the receiving window 60 to reach the receiver 30, and the intensity of the infrared light reaching the object under test 70 after passing through the receiving window 60 is sufficient for testing.

[0056] For example, when the transmitting window 50 and receiving window 60 are opened on the screen, the transmitting window 50 can be opened directly above the transmitting end 20, and the receiving window 60 can be opened directly above the receiving end 30. That is, the line connecting the center of the transmitting end 20 and the center of the transmitting window 50 is perpendicular to the substrate 12, and the line connecting the center of the receiving end 30 and the center of the receiving window 60 is perpendicular to the substrate 12. The size of the transmitting window 50 can be determined according to the projection range of the emitted light, and the size of the receiving window 60 can also be determined according to the projection range of the reflected light. In addition, the positions of the transmitting window 50 and the receiving window 60 can be appropriately offset. The specific offset distance can be determined according to the actual design requirements, with the aim of allowing as much infrared light as possible to pass through the transmitting window 50 and the receiving window 60.

[0057] In this embodiment, when setting up the time-of-flight camera, the distance between the transmitter 20 and the receiver 30 in the time-of-flight camera is set as a second distance, wherein the second distance is greater than the first distance and greater than a threshold distance. The threshold distance refers to the following: when the transmitter 20 and receiver 30 are at a certain distance, stray light reflected from the inner layer of the screen in the infrared light emitted by the transmitter 20 will not be received by the receiver 30, or the amount of stray light received by the receiver 30 will be reduced so as not to affect the imaging of the measured object 70 and the calculation of the depth information 80, or the impact on the imaging of the measured object 70 and the calculation of the depth information 80 is within an acceptable range. This "certain distance" is referred to as the threshold distance.

[0058] It should be noted that, in practical applications, those skilled in the art can determine the threshold distance based on the performance of the time-of-flight camera, the image sensor 40, and the specific performance requirements of the electronic device. For example, different electronic devices may have different requirements for the accuracy of imaging and depth information 80 of the measured object 70, which may lead to different threshold distances.

[0059] In this embodiment, the distance between the transmitter 20 and the receiver 30 is set as a second distance. Since the second distance is greater than the first distance and greater than the threshold distance, it essentially increases the distance between the transmitter 20 and the receiver 30. The transmitter window 50 and the receiver window 60 are set corresponding to the transmitter 20 and the receiver 30, respectively. When the distance between the transmitter 20 and the receiver 30 increases, the distance between the transmitter window 50 and the receiver window 60 also increases accordingly. That is, the length of the screen located between the transmitter window 50 and the receiver window 60 increases.

[0060] like Figure 3As shown, after the transmitter 20 emits infrared light, some of the infrared light enters the inner layer of the screen and is continuously reflected between the inner layers. Due to the increased length of the screen between the transmitter window 50 and the receiver window 60, the number of reflections of the infrared light in the inner layers of the screen increases. By increasing the number of reflections, the energy of the infrared light gradually weakens, making it impossible for it to be transmitted to the image sensor 40 through the receiver 30. This effectively prevents the introduction of stray light information, allowing the receiver 30 to receive the infrared light reflected from the surface of the object 70 being measured. Alternatively, by increasing the length of the screen between the transmitter window 50 and the receiver window 60, the number of reflections of the infrared light in the inner layers of the screen increases, resulting in very weak stray light energy finally received by the receiver 30. This weak stray light will not affect the imaging of the object 70 or the calculation of the depth information 80, or the effect will be minimal and within an acceptable range.

[0061] When setting up the transmitter 20 and receiver 30, they can be positioned at opposite ends of the screen. Specifically, transmitter 20 is positioned directly below the first end of the screen, and receiver 30 is positioned directly below the second end of the screen. The first and second ends of the screen can refer to either the two ends along the length or width of the screen. Positioning transmitter 20 and receiver 30 directly below the first and second ends of the screen represents the maximum distance that transmitter 20 and receiver 30 can maintain in that direction. In other words, the second distance is at its maximum value in either the length or width of the screen. This also maximizes the screen length between the transmitting window 50 and the receiving window 60, resulting in the longest transmission distance of stray light within the inner layers of the screen, the most reflections between the inner layers, and the best stray light attenuation. Therefore, when the influence of stray light is weakened by increasing the distance between the transmitter 20 and the receiver, placing the transmitter 20 and the receiver 30 at opposite ends of the screen minimizes the impact of stray light on the imaging of the object under test 70 and the calculation of depth information 80.

[0062] In this embodiment, besides increasing the distance between the transmitter 20 and receiver 30 in the time-of-flight camera to reduce stray light interference and improve the accuracy of depth information acquisition, the interference of stray light can also be reduced by setting the light-absorbing structure 13, thereby improving the accuracy of depth information acquisition.

[0063] refer to Figure 4 , Figure 4 This is a schematic diagram of another time-of-flight measurement system provided in an embodiment of this application. Figure 4As shown, the structural components include a screen and a time-of-flight camera, wherein the time-of-flight camera is positioned below the screen and includes a transmitter 20 and a receiver 30. The screen of this electronic device can be a full-screen display composed of organic light-emitting diodes (OLEDs) with self-emissive properties. The screen generally includes a multi-layer structure, comprising at least: a substrate 12, an anode, an organic layer, a conductive layer, an emitting layer, and a cathode. The anode, organic layer, conductive layer, emitting layer, and cathode together constitute the screen's light-emitting layer 11. The substrate 12 supports the entire screen structure, and the screen's light-emitting layer 11 is located above the substrate 12.

[0064] To reduce stray light transmission within the screen, this embodiment provides an anti-light structure 13 on the screen substrate 12. The screen substrate 12 can be made of materials such as transparent plastic, glass, or metal foil. When setting up the time-of-flight camera, the distance between the transmitter 20 and the receiver 30 does not necessarily need to be set according to the requirements of the aforementioned embodiments. For example, the distance between the transmitter 20 and the receiver 30 can be a first distance, a second distance, or the transmitter 20 and the receiver 30 can be located at opposite ends of the screen. The following description uses the distance between the transmitter 20 and the receiver 30 as the first distance.

[0065] refer to Figure 5 , Figure 5 This is a schematic diagram of the screen structure in a time-of-flight measurement system provided in an embodiment of this application. Figure 5 As shown, the screen includes a screen light-emitting layer 11 and a substrate 12. The screen light-emitting layer 11 is disposed above the substrate 12. A matting film layer 131 is disposed in the substrate 12. The matting film layer 131 can be disposed on the surface of the substrate 12 near the screen light-emitting layer 11, or it can be disposed throughout the entire substrate 12. When setting the matting film layer 131, it can be disposed on the lower substrate by spin coating, spraying, or casting. Furthermore, the matting film layer 131 can also be disposed on the upper surface of the screen light-emitting layer 11; that is, a matting film layer 131 is disposed on both the upper and lower surfaces of the screen light-emitting layer 11. This method of setting the matting film layer 131 is simple to operate and mass-producible. Of course, this embodiment only provides a simple example of how to set the matting film layer 131 and does not limit the specific method of setting the matting film layer 131.

[0066] like Figure 5As shown, a portion of the infrared light emitted from the transmitter 20 of the time-of-flight camera enters the screen through the emission window 50. This portion of infrared light is referred to as stray light. The stray light propagates within the screen's emissive layer 11. The stray light is reflected when it encounters both the upper and lower surfaces of the emissive layer 11, with the lower surface of the emissive layer 11 adhering to the upper surface of the substrate 12. By providing an anti-glare film layer 131 on the upper surface of the substrate 12 or within the substrate 12, the anti-glare film layer 131 absorbs the stray light when it is reflected back to the substrate 12. Since the stray light undergoes multiple reflections within the inner layers of the screen, each reflection to the anti-glare film layer 131 on the substrate 12 results in absorption by the anti-glare film layer 131. After multiple reflections and absorptions, the stray light cannot pass through the emissive layer 11 and be received by the receiver 30 of the time-of-flight camera, thus preventing its transmission to the image sensor 40. Alternatively, the stray light energy received by the receiver 30 of the time-of-flight camera after passing through the screen light-emitting layer 11 and transmitted to the image sensor 40 is very weak and will not interfere with the imaging and depth calculation of the object under test 70.

[0067] When setting the matte film layer 131, a colorless and transparent matte film layer 131 is generally selected. The colorless and transparent matte film layer 131 ensures the projection efficiency of the screen, allowing the screen after setting the matte film layer 131 to meet conventional display requirements. Furthermore, the matte film layer 131 can be a diffuse reflection coating layer made of diffuse reflection paint, which is composed of a base material, diffuse reflection material, high thermal conductivity material, filler, etc. It is uniformly formed as a high diffuse reflection coating by spraying or applying adhesive to aluminum, ceramic, copper substrates, or various reflectors. The thickness of the coated matte film layer 131 is generally controlled between 5-70 μm, achieving the elimination of stray light reflected from the inner layer of the screen without affecting the display characteristics of the screen within the interval area (the screen between the transmitting window 50 and the receiving window 60).

[0068] In another embodiment of this application, the matting structure 13 may also be a microstructure layer 132 disposed in the substrate 12. (See reference...) Figure 6 , Figure 6 This is a schematic diagram of another screen structure provided in an embodiment of this application for time-of-flight measurement system. (See diagram below.) Figure 6As shown, the screen includes a screen light-emitting layer 11 and a substrate 12. The screen light-emitting layer 11 is disposed above the substrate 12. A microstructure layer 132 is disposed in the substrate 12. The microstructure layer 132 can be disposed throughout the entire substrate 12, or it can be disposed on the side of the substrate 12 closest to the screen light-emitting layer 11. The microstructure layer 132 is composed of multiple structural units, each of which can be independent of each other. The minimum unit size of each structural unit is 0.05 μm, where the unit size can refer to the length, width, or diameter of the structural unit. The minimum thickness of each structural unit is 0.1 μm, and the minimum spacing between two adjacent structural units is 0.05 μm. The structural units can be zigzag, arc-shaped, triangular, rhomboid, stepped, or other shapes. Each structural unit in the microstructure layer 132 can be of the same shape or different shapes. For example, the microstructure layer 132 can be composed of zigzag structural units, triangular structural units, and rhomboid structural units, or it can be composed entirely of zigzag structural units or triangular structural units. The embodiments of this application do not limit the specific shape of the structural units, and the structural units can also be made into irregular shapes. However, for ease of processing, the structural units are generally made into regular shapes, and the microstructure layer 132 is generally composed of multiple structural units of the same shape.

[0069] When fabricating the microstructure layer 132, methods such as laser etching, chemical etching, sandblasting, laser atomization, and microstructure film pressing can be used to fabricate the microstructure layer 132 on the substrate 12. Of course, this embodiment only provides a simple list of ways to set the microstructure layer 132 and does not limit the specific way of setting the microstructure layer 132.

[0070] like Figure 6As shown, some infrared light (stray light) emitted from the transmitter 20 of the time-of-flight camera enters the screen through the emission window 50. The stray light is transmitted through the screen's emissive layer 11. The stray light is reflected when it encounters both the upper and lower surfaces of the emissive layer 11, with the lower surface of the emissive layer 11 adhering to the upper surface of the substrate 12. A microstructure layer 132 is provided on the upper surface of the substrate 12 or within the substrate 12. Since the microstructure layer 132 is composed of multiple structural units, each structural unit and the gaps between structural units can form multiple tiny reflective surfaces. When stray light is reflected onto the microstructure layer 132 of the substrate 12, the stray light is reflected on these multiple tiny reflective surfaces. Because there is also a certain angle between each tiny reflective surface, the stray light reflected from these multiple tiny reflective surfaces can weaken each other's energy. Therefore, during the transmission process of the screen's emissive layer 11, the stray light will be reflected multiple times onto the microstructure layer 132. Each time the light is reflected onto the microstructure layer 132, it is scattered by multiple tiny reflective surfaces within the microstructure layer 132. The scattered stray light and the continuously transmitted stray light do not travel in the same direction, causing the energy of the stray light to be continuously weakened during its transmission within the inner layer of the screen. Ultimately, this prevents the stray light from being transmitted to the image sensor 40 via the time-of-flight camera receiver 30, thus avoiding the image sensor 40 receiving infrared light information reflected from a non-actual object surface near the receiver 30. Alternatively, after being scattered and weakened by the microstructure layer 132, the stray light energy received by the time-of-flight camera receiver 30 and transmitted to the image sensor 40 via the screen light-emitting layer 11 is extremely weak and will not interfere with the imaging and depth calculation of the measured object 70.

[0071] In another embodiment of this application, the matting structure 13 may further be an matting film layer 131 disposed in the substrate 12 and a microstructure layer 132 disposed in the substrate 12. For example... Figure 7 As shown, Figure 7 This is another schematic diagram of the screen structure in a time-of-flight measurement system provided in an embodiment of this application. For example... Figure 6 As shown, the screen includes a screen light-emitting layer 11 and a substrate 12. The screen light-emitting layer 11 is disposed above the substrate 12. The substrate 12 has an anti-glare film layer 131 and a microstructure layer 132 disposed thereon, wherein the anti-glare film layer 131 is disposed on the microstructure layer 132. The description of the anti-glare film layer 131 and the microstructure layer 132 can be referred to the description in the foregoing embodiments, and will not be repeated here.

[0072] like Figure 7As shown, some infrared light (stray light) emitted from the transmitter 20 of the time-of-flight camera enters the screen through the emission window 50. The stray light is transmitted through the screen's light-emitting layer 11. The stray light is reflected when it encounters both the upper and lower surfaces of the light-emitting layer 11, with the lower surface of the light-emitting layer 11 adhering to the upper surface of the substrate 12. By providing an anti-glare film layer 131 and a microstructure layer 132 on the substrate 12, the microstructure layer 132 can scatter and weaken the stray light reflected to it. When the stray light is reflected to the anti-glare film layer 131, it can be absorbed by the anti-glare film layer 131. By simultaneously providing the anti-glare film layer 131 and the microstructure layer 132, the interference of stray light can be better reduced, avoiding any impact on the imaging and depth calculation of the object under test 70.

[0073] Furthermore, in this embodiment, an extinction structure 13 can be provided on the substrate 12. The extinction structure 13 includes an extinction film layer 131 and / or a microstructure layer 132. When setting up the time-of-flight camera, the distance between the transmitter 20 and the receiver 30 is set to be greater than a threshold distance. By increasing the distance between the screen light-emitting layer 11 between the transmitter 20 and the receiver 30, the transmission of stray light is weakened. Furthermore, by providing the extinction structure 13, stray light is scattered, weakened, or absorbed. By simultaneously reducing stray light interference through multiple methods, the imaging and depth calculation accuracy of the object under test 70 is improved. The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

[0074] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0075] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the scope of protection of this application includes the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of this application.

[0076] The above provides a detailed description of the time-of-flight measurement system and electronic device provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

[0077] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A time-of-flight measurement system, comprising a screen and a time-of-flight camera, characterized in that, The time-of-flight camera is disposed on one side of the screen. The time-of-flight camera includes a transmitter and a receiver. The screen includes a screen light-emitting layer and a substrate. The screen light-emitting layer is disposed on the substrate. The screen has a transmitter window and a receiver window. The substrate is provided with a microstructure layer, which is composed of multiple structural units. Each structural unit and the gaps between the structural units form multiple reflective surfaces. A matting film layer is disposed on the surface of the substrate facing the screen light-emitting layer, and the matting film layer is disposed on the surface of the screen light-emitting layer away from the substrate. The matting film layer is used to absorb stray light entering the screen light-emitting layer. Along a direction parallel to the substrate, both the microstructure layer and the matting film layer are disposed between the emission window and the receiving window; The infrared light emitted by the transmitting end passes through the transmitting window, and the receiving end receives the infrared light passing through the receiving window; along the length or width direction of the screen, the transmitting end is located directly below the first end of the screen, and the receiving end is located directly below the second end of the screen; the line connecting the center of the transmitting end and the center of the transmitting window is perpendicular to the substrate, and the line connecting the center of the receiving end and the center of the receiving window is perpendicular to the substrate. The distance between the transmitter and the receiver is greater than or equal to a threshold distance, where the threshold distance refers to the distance that can reduce stray light entering the receiver through the screen's light-emitting layer.

2. The measurement system according to claim 1, characterized in that, The shape of the structural unit is one or more of the following: sawtooth, arc, triangle, rhombus, and stepped.

3. The measurement system according to claim 2, characterized in that, The structural unit has a unit size of 0.05 μm, a thickness of 0.1 μm, and a spacing of 0.05 μm between two adjacent structural units.

4. The measurement system according to claim 1, characterized in that, The matte film layer is a colorless and transparent film layer, or the matte film layer is a diffuse reflection coating layer.

5. The measurement system according to claim 4, characterized in that, The thickness of the matting film layer is 5 μm to 70 μm.

6. The measurement system according to claim 4 or 5, characterized in that, The matte film layer is made by spin coating, spray coating or casting.

7. The measurement system according to claim 1, characterized in that, The microstructure layer is made by laser etching, chemical etching, sandblasting, laser atomization, or molding.

8. An electronic device, characterized in that, Includes the time-of-flight measurement system as described in any one of claims 1-7.

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