A light emitting component, a time-of-flight camera module and a mobile terminal

Abstract

A light emitting component, a time-of-flight camera module and a mobile terminal, relating to the technical field of electronic products. The light emitting component comprises: a substrate (1), a laser light source array and a lens array, wherein the laser light source array is arranged on the substrate (1); the lens array is arranged on the light emitting side of the laser light source array, a lens (3) in the lens array is arranged opposite to at least one laser light source (2) in the laser light source array, the light emitting surface of the lens (3) is a spherical surface, and at least part of the laser light sources (2) are eccentrically arranged with the corresponding lens (3). The light emitting component uses a lens (3) with a spherical light emitting surface to change the divergence angle. During the manufacturing process, a lens (3) with the same structure and a laser light source (2) with the same structure are used, and by changing the eccentricity between the laser light source (2) and the lens (3), a light emitting component with different divergence angles can be manufactured.

Description

Technical Field

[0001] The present application relates to the technical field of electronic products, and in particular to a light emitting component, a time-of-flight camera module and a mobile terminal. Background Art

[0002] 3D depth sensing technology is an inevitable trend in the development of emerging fields such as consumer electronics, automotive electronics, LiDAR, biosensing, and artificial intelligence. One of the main implementation schemes of 3D depth sensing is to introduce time-of-flight ranging technology based on traditional 2D cameras to obtain the depth information of the image, that is, the time-of-flight (TOF) camera module, to achieve 3D depth measurement. Specifically, a pulse-pumped light source is used to generate a short pulse beam that is projected onto the target object. The beam is reflected by the target object and received by the photosensitive component. The distance to the object, that is, the depth information, is calculated by calculating the time or phase difference from the light pulse being emitted to being received.

[0003] The divergence angle of the laser light source is fixed, but in practical applications, sometimes the divergence angle needs to be increased, and sometimes it needs to be reduced. For example, in the TOF camera module, in order to obtain the largest possible illumination field of view and detection effect, the light beam emitted by the TOF camera module needs to have a specific intensity distribution and field of view (FOV). For example, the FOV may be as large as 50° while the intensity is evenly distributed. However, the divergence angle of the laser light source is generally 10° to 30°, so the laser light source cannot meet the application requirements of the TOF camera module.

[0004] In the prior art, reference Figure 1 The light emitted by the laser light source 01 is modulated by the light diffuser 02. The surface of the light diffuser 02 has an irregular concave-convex structure. The light is diffused by the concave-convex structure to make the light beam emitted by the laser light source 01 have a larger divergence angle after passing through the light diffuser 02. Figure 1 Increase the divergence angle α of the laser light source to β).

[0005] During the assembly of the time-of-flight camera module, the light diffusion angle of the light using the light diffuser 02 of the same structure is fixed and unique. Therefore, in order to achieve different divergence angles, it is only possible to install light diffusers of different structures, which will increase the manufacturing cost accordingly.

[0006] Currently, there is a need for a technical solution that can produce a time-of-flight camera module with different divergence angles by only changing the positional relationship between the components without changing the component structure, so as to reduce the manufacturing cost. Summary of the invention

[0007] The embodiments of the present application provide a light emitting component, a time-of-flight camera module and a mobile terminal. The main purpose is to provide a light emitting component having a lens array arranged on the light output side of a laser light source array, so as to utilize the eccentric arrangement between the laser light source and the lens to change the divergence angle of the light emitted from the lens.

[0008] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0009] In the first aspect, the present application provides a light emitting component for being arranged in a time-of-flight camera module, the light emitting component comprising: a substrate, a laser light source array and a lens array, the laser light source array being arranged on the substrate, the lens array being arranged on the light emitting side of the laser light source array, one lens in the lens array being arranged opposite to at least one laser light source in the laser light source array, the light emitting surface of the lens being a spherical surface, and at least part of the laser light sources being arranged eccentrically with the corresponding lenses.

[0010] The light emitting component provided in the embodiment of the present application is a lens array arranged on the light emitting side of the laser light source array, and the light emitting surface of the lens in the lens array is a spherical surface. When the light of the laser light sources in the laser light source array is transmitted to the light emitting surface of the lens, the divergence angle is changed by refraction of the light by the spherical light emitting surface, and at least part of the laser light sources are eccentrically arranged with the lens to achieve the change of the divergence angle distribution of the laser light source array.

[0011] When assembling the light emitting component, the eccentricity between the laser light source and the lens is changed so that the laser light source component has different divergence angles. That is to say, when assembling the light emitting component, when the lens of the same structure and the laser light source of the same structure are used, by changing the eccentricity of the laser light source and the lens, a variety of light emitting components with different divergence angles can be made. Because the shape of the arc surface of the lens relative to the laser light source is different when the eccentricity is different, the inclination angle of the normal of the arc surface is also different, and then the divergence angle of the light refracted from the light exit surface of the lens is also different. Therefore, in order to achieve different divergence angles, it can be achieved by changing the eccentricity between the laser light source and the lens, so that in the time-of-flight camera module, the eccentric arrangement of the laser light source array and the lens array can achieve the change of the divergence angle distribution of the laser light source array. Compared with the prior art of changing the divergence angle by changing the light diffuser, it is more convenient to implement and will reduce the manufacturing cost.

[0012] In a possible implementation of the first aspect, the laser light source array forms N light-emitting areas, there are at least two laser light sources in each light-emitting area, N is an integer greater than 1, the eccentricities of some laser light sources in every two light-emitting areas are equal, or the eccentricities of all laser light sources in every two light-emitting areas are not equal.

[0013] Since the eccentricity of some laser light sources in every two light-emitting areas is equal, or the eccentricity of all laser light sources in every two light-emitting areas is not equal, the far-field light spots formed by the light emitted by any two light-emitting areas after passing through the corresponding lens array are different. In specific implementation, the target far-field light spot can be divided into N areas according to the target far-field light spot, so that the light spot in each area is the target far-field sub-spot, and the N light-emitting areas of the laser light source array are one-to-one with the N areas of the target far-field light spot, and the far-field light spot formed by each light-emitting area is consistent with the corresponding target far-field sub-spot, so that ranging can be achieved.

[0014] In a possible implementation of the first aspect, each light-emitting area has a power supply unit, which is used to light up and extinguish all laser light sources in the corresponding light-emitting area, and multiple power supply units are connected in parallel. Since each light-emitting area of ​​the laser light source has a power supply unit, and multiple power supply units are connected in parallel, when performing long-distance ranging, only one light-emitting area can be lit at a time. If the input power of all laser light sources is 20W, and there are 100 laser light sources, when the existing solution of lighting all laser light sources at once is adopted, the input current of each laser light source is 0.1A. If the solution provided in the embodiment of the present application is adopted, the laser light source is divided into 10 light-emitting areas, and each light-emitting area has 10 laser light sources, then each time it is lit, the input current of each laser light source is 1A, which is significantly higher than the input current of 0.1A, so the brightness of the laser light source is significantly improved to achieve long-distance ranging.

[0015] In a possible implementation of the first aspect, the laser light source array includes a first laser light source and a second laser light source that are adjacent to each other, the lens array includes a first lens, the first lens is arranged on the light exit side of the first laser light source and the light exit side of the second laser light source, the eccentricity between the first laser light source and the first lens is a first eccentricity, the eccentricity between the second laser light source and the first lens is a second eccentricity, and the first eccentricity is not equal to the second eccentricity. In other words, when the first eccentricity between the first laser light source and the first lens is not equal to the second eccentricity between the second laser light source and the first lens, the first laser light source and the second laser light source can share a lens, which will reduce the number of lenses to simplify the structure of the entire light emitting assembly. In a possible implementation of the first aspect, the substrate is made of a light-transmitting conductive material, and the substrate has a first surface and a second surface that are opposite to each other; the laser light source includes an N-type restriction layer, an active layer, a P-type restriction layer, an anode electrode layer, and a cathode electrode layer, and the N-type restriction layer, the active layer, the P-type restriction layer, and the anode electrode layer are stacked from bottom to top on the first surface, and the cathode electrode layer is also arranged on the first surface; the lens array is arranged on one side of the second surface, and the light-emitting surface of the lens is opposite to the second surface. Since the stacked anode electrode layer, the N-type restriction layer, the active layer, and the P-type restriction layer are located on the first surface, and the cathode electrode layer is also located on the first surface, that is, the two electrode layers of the laser light source are coplanar. In this way, in a specific implementation, the cathode electrode layer and the anode electrode layer located on one side of the first surface can be electrically connected to the corresponding anode pin and cathode pin of the driving circuit through a welding structure. Compared with the two electrode layers in the prior art that are not on the same surface, it is not necessary to use a connecting wire to electrically connect the anode electrode layer to the driving circuit, which simplifies the structure and correspondingly simplifies the process steps.

[0016] In a possible implementation of the first aspect, a circuit board is further included, a driving circuit is arranged on the circuit board, the cathode electrode layer is electrically connected to the cathode pin of the driving circuit through a first welding structure, and the anode electrode layer is electrically connected to the anode pin of the driving circuit through a second welding structure. Since the first surface of the substrate faces the circuit board, and the cathode electrode layer and the anode electrode layer are both located on the first surface, the cathode electrode layer and the anode electrode layer can be electrically connected to the corresponding cathode pin and anode pin of the driving circuit through the welding structure. Compared with the connection method using connecting wires, firstly, the operation process is simplified, and secondly, the size of the entire light emitting component in the height direction is correspondingly reduced, so that the entire light emitting component meets the requirements of miniaturization design.

[0017] In a possible implementation of the first aspect, the lens is integrally formed with the substrate; or, the lens is connected to the substrate via a metal bonding structure. Compared with the existing bonding method, the integral molding or metal bonding structure connection will not cause the lens to fall off easily on the basis of changing the divergence angle of the light emitted by the laser light source. In this case, there is no need to set up a detector for monitoring whether the lens falls off, thereby simplifying the structure of the entire light emitting component, and correspondingly reducing the size of the entire light emitting component to meet the requirements of miniaturization design.

[0018] In a possible implementation of the first aspect, the substrate is made of a conductive material, and the substrate has a first surface and a second surface relative to each other; the laser light source includes an N-type confinement layer, an active layer, a P-type confinement layer, an anode electrode layer and a cathode electrode layer, the N-type confinement layer, the active layer, the P-type confinement layer and the anode electrode layer are stacked from bottom to top on the first surface, and the cathode electrode layer is arranged on the second surface; the lens array is arranged on one side of the first surface, and the light emitting surface of the lens is opposite to the first surface.

[0019] In a possible implementation of the first aspect, it also includes a circuit board, on which a driving circuit is arranged, the cathode electrode layer is electrically connected to the cathode pin of the driving circuit through a welding structure, and the anode electrode layer is electrically connected to the anode pin of the driving circuit through a connecting wire.

[0020] In a possible implementation of the first aspect, a first surface on which an N-type confinement layer, an active layer, a P-type confinement layer, and an anode electrode layer are formed is covered with a light-transmitting cover layer, and a lens is formed on a surface of the light-transmitting cover layer opposite to the first surface. By covering the first surface with a laser light source with a light-transmitting cover layer, so that the lens is formed on a side of the light-transmitting cover layer away from the first surface, the connection strength of the lens is effectively guaranteed.

[0021] In a possible implementation manner of the first aspect, the lens is a convex lens or a concave lens.

[0022] In a possible implementation manner of the first aspect, the lenses in the lens array are arranged in a one-to-one correspondence with the laser light sources in the laser light source array.

[0023] In the second aspect, the present application also provides a time-of-flight camera module, comprising: a light emitting component and a photosensitive component, the light emitting component is the light emitting component in the above-mentioned first aspect or any implementation of the first aspect, the laser light source array is used to emit light, and the light emitted by the laser light source array passes through the lens array and is projected onto the target object; the photosensitive component is used to receive light reflected from the target object, and based on the time difference or phase difference between the light emitted by the light emitting component and the reflected light received by the photosensitive component, the distance of the target object is measured.

[0024] In a third aspect, the present application also provides a mobile terminal, comprising the time-of-flight camera module in the implementation method of the above-mentioned second aspect.

[0025] The time-of-flight camera module provided in the second aspect of the embodiment of the present application and the mobile terminal provided in the third aspect include the light emitting component provided in the first aspect. Therefore, the time-of-flight camera module and mobile terminal provided in the embodiment of the present application and the light emitting component of the above-mentioned technical solution can solve the same technical problems and achieve the same expected effects.

[0026] In a fourth aspect, the present application also provides a method for preparing a light emitting component, the method comprising:

[0027] Based on the target divergence angle of the light emitting component and the divergence angle of the laser light source, the eccentricity between the laser light source and the lens is determined; a laser light source array is formed on a substrate, and then a lens array is arranged according to the eccentricity to obtain a light emitting component in which the laser light source array and the lens array are eccentrically arranged. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of a light emitting component in the prior art;

[0029] Figure 2 This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0030] Figure 3 This is a schematic diagram of the positional relationship between the laser light source and the lens in the embodiment of the present application;

[0031] Figure 4a This is a schematic diagram of the positional relationship when the eccentricity between the laser light source and the lens in the embodiment of the present application is zero;

[0032] Figure 4b This is a schematic diagram of the positional relationship when the eccentricity between the laser light source and the lens in the embodiment of the present application is zero;

[0033] Figure 4c This is a schematic diagram of the positional relationship when the eccentricity between the laser light source and the lens in the embodiment of the present application is D1;

[0034] Figure 4d This is a schematic diagram of the positional relationship when the eccentricity between the laser light source and the lens in the embodiment of the present application is D2;

[0035] Figure 5a The far-field light spot formed by the laser light source array with a divergence angle of 20° in the embodiment of the present application;

[0036] Figure 5b The far-field light spot is formed by the laser light source array with a divergence angle of 20° after passing through the lens array in the embodiment of the application;

[0037] Figure 6 This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0038] Figure 7 This is a schematic diagram of the positional relationship between the first laser light source, the second laser light source and the first lens in the light emitting assembly of the embodiment of the present application;

[0039] Figure 8 This is a schematic diagram of the structure in which a laser light source array in a light emitting assembly according to an embodiment of the present application forms 12 light emitting areas;

[0040] Fig. 9 for Figure 8 CC section view;

[0041] Fig.10 for Figure 8 The far-field spot pattern formed;

[0042] Fig.11 This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0043] Fig.12 This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0044] Fig.13 This is a schematic diagram of the connection relationship between the substrate and the laser light source in the light emitting component of the embodiment of the present application;

[0045] Fig.14 This is a schematic diagram of the connection relationship between the substrate, the laser light source and the circuit board in the optical emission component of the embodiment of the present application;

[0046] Fig.15 This is a schematic diagram of the connection relationship between the substrate and the laser light source in the light emitting component of the embodiment of the present application;

[0047] Fig.16 This is a schematic diagram of the connection relationship between the substrate, the laser light source and the circuit board in the optical emission component of the embodiment of the present application;

[0048] Fig.17a This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0049] Fig.17b for Fig.17a AA section view;

[0050] Fig.17c for Fig.17a BB cross-section diagram;

[0051] Fig.17d This is a schematic diagram of the connection relationship between the substrate and the laser light source in the light emitting component of the embodiment of the present application;

[0052] Fig.18 This is a schematic diagram of the structure of the light emitting component of the embodiment of the present application;

[0053] Fig.19 A schematic diagram of a structure for forming multiple light emitting components according to an embodiment of the present application;

[0054] Fig. 20 A schematic diagram of the structure of forming multiple light emitting components according to an embodiment of the present application.

[0055] Reference numerals:

[0056] 01-laser light source; 02-light diffuser; 1-substrate; 2-laser light source; 201-cathode electrode layer; 202-N-type confinement layer; 203-active layer; 204-P-type confinement layer; 205-anode electrode layer; 206-grating structure; 207-reflecting mirror; 208-waveguide; 21-first laser light source; 22-second laser light source; 3-lens; 31-first lens; 4-circuit board; 5-metal bonding structure; 6-light-transmitting covering layer; 7-connecting wires; 8-power supply unit. DETAILED DESCRIPTION

[0057] The embodiments of the present application relate to a light emitting component, a time-of-flight camera module, a mobile terminal, and a method for preparing the light emitting component. The light emitting component, the time-of-flight camera module, the mobile terminal, and the method for preparing the light emitting component are described in detail below in conjunction with the accompanying drawings.

[0058] In a first aspect, an embodiment of the present application provides a light emitting component, which is used to be arranged in a time-of-flight camera module, referring to Figure 2 The light emitting assembly includes a substrate 1, a laser light source array (composed of a plurality of laser light sources 2) and a lens array (composed of a plurality of lenses 3); wherein the laser light source array is arranged on the substrate 1, the lens array is arranged on the light emitting side of the laser light source array, one lens in the lens array is arranged opposite to at least one laser light source in the laser light source array, and at least part of the laser light sources are arranged eccentrically with the corresponding lenses. Figure 3 The light-emitting surface (P surface) of the lens 3 is a spherical surface. There is an eccentricity D between the laser light source 2 and the corresponding lens 3. The eccentricity D is the distance between the center of the laser light source 2 and the perpendicular bisector L of the light-emitting surface P of the lens 3.

[0059] It should be noted that: all laser light sources and corresponding lenses may be arranged eccentrically, or part of the laser light sources and corresponding lenses may be arranged eccentrically.

[0060] The principle of changing the divergence angle of the light emitting component is that when the light emitted by the laser light source 2 passes through the lens 3, the light is refracted by the spherical light emitting surface to change the divergence angle of the light.

[0061] Since the light-emitting surface of the lens is a spherical surface, in the process of assembling the optical emission component, if you want to achieve different divergence angles of the light refracted from the lens, you can change the eccentricity between the laser light source and the lens. Because when the eccentricity is different, the arc shape of the lens opposite to the laser light source is different (such as Figure 4a and Figure 4c As shown in Figure 2, the inclination angle of the normal line of the curved surface is also different, and thus the divergence angle of the light refracted from the light exiting surface of the lens is also different. Figure 4a The laser light source 2 shown is a point light source, and Figure 4a The eccentricity is zero; Figure 4c The laser light source 2 shown is a point light source, and Figure 4c The eccentricity D1 is greater than zero; Figure 4d The laser light source 2 shown is a surface light source, and Figure 4d The eccentricity D2 is also greater than zero.

[0062] Figure 4a and Figure 4c The laser light source 2 has the same structure as the lens 3, and the lens 3 has the same structure. Figure 4a and Figure 4c It is obvious that when the eccentricity changes, the divergence angle of the light emitted from the lens 3 changes significantly, that is, the far-field light spot formed is also different. Therefore, by using a laser light source of the same structure and a lens of the same structure, the divergence angle of the light emitted from the lens can be changed by changing the eccentricity to obtain a light emitting component with different divergence angles. Compared with the prior art method of changing the divergence angle by replacing the light diffuser, firstly, it will reduce the manufacturing cost, and secondly, it will save the complicated installation process of the light diffuser. By changing the eccentricity between the laser light source and the lens to achieve different divergence angles, not only the structure is simple, but also the implementation is convenient.

[0063] Figure 5a It is a circular spot formed when the divergence angle of the light emitted by the laser light source array is about 20°. Figure 5b It is a rectangular light spot with a divergence angle greater than 60° formed after lens modulation.

[0064] When the eccentricity between the laser light source 2 and the lens 3 is zero (such as Figure 4a and Figure 4bAs shown in the figure, the divergence angle of the light emitted from the lens may increase or decrease. Whether it increases or decreases is related to the structural size of the lens. However, no matter whether it increases or decreases, the center of the far-field spot formed by the light emitted from the lens is still located on the extension line of the center of the laser light source. In specific applications, if the center of the far-field spot formed by the light emitted from the lens is still located on the extension line of the center of the laser light source, the eccentricity between the laser light source and the lens is selected to be zero, and then the corresponding lens structure is selected according to whether the divergence angle increases or decreases.

[0065] When the eccentricity between the laser light source 2 and the lens is greater than zero (such as Figure 4c and Figure 4d As shown in the figure, the center of the far-field spot formed by the light emitted from the lens is not on the extension line of the center of the laser light source, that is, an offset occurs, and the specific offset is related to the eccentricity. In specific implementation, if the center of the far-field spot formed by the light emitted from the lens is not on the extension line of the center of the laser light source, the eccentricity between the laser light source and the lens is made greater than zero, and the size of the eccentricity is changed according to the offset.

[0066] Reference Figure 2 and Figure 6 , Fig.11 and Fig.12 The lens provided in the embodiment of the present application can be a convex lens or a concave lens. During specific implementation, the lens type can be selected according to the design requirements of the divergence angle.

[0067] In some embodiments, reference Figure 7 , the laser light source array includes a first laser light source 21 and a second laser light source 22, the lens array includes a first lens 31, the first lens 31 is arranged on the light exit side of the first laser light source 21 and the light exit side of the second laser light source 22, and the first eccentricity between the first laser light source 21 and the first lens 31 is D3, the second eccentricity between the second laser light source 22 and the first lens 31 is D4, and the first eccentricity D3 is not equal to the second eccentricity D4. In other words, when the eccentricity of the first laser light source 21 is not equal to the eccentricity of the second laser light source 22, the lens corresponding to the first laser light source 21 and the lens corresponding to the second laser light source 22 can be one lens, which can produce the following technical effects: one lens is reduced, which simplifies the structure of the entire light emitting component, and correspondingly simplifies the assembly process of the light emitting component.

[0068] By analogy, when the laser light source further includes a third laser light source, a fourth laser light source, a fifth laser light source, etc., and the eccentricity between each laser light source and the corresponding lens is unequal, then one lens can be used.

[0069] Of course, the embodiment of the present application also protects that the number of lenses is equal to the number of laser light sources, and the lenses and laser light sources are one-to-one.

[0070] Since the eccentricity between each two laser light sources and the corresponding lenses is the same or different, it may happen that when the laser light sources 2 are evenly arranged, the lenses 3 are unevenly arranged; or, the lenses 3 are evenly arranged, and the laser light sources 2 are unevenly arranged; or, both the lenses 3 and the laser light sources 2 are unevenly arranged. The specific arrangement of the lenses and laser light sources still needs to be determined according to actual needs.

[0071] In some embodiments, the laser light source array forms N light emitting areas, there are at least two laser light sources in each light emitting area, N is an integer greater than 1, the eccentricities of some laser light sources in every two light emitting areas are equal, or the eccentricities of all laser light sources in every two light emitting areas are not equal.

[0072] That is to say, since the eccentricities of some laser light sources in every two light-emitting areas are equal, or the eccentricities of all laser light sources in every two light-emitting areas are not equal, the far-field light spots formed by any two light-emitting areas are different.

[0073] For example, refer to Figure 8 , the laser light source array 2 is divided into 12 light-emitting areas, and the 12 light-emitting areas are arranged in a 2*6 array, namely area 1, area 2, area 3, area 4...area 12, Fig. 9 yes Figure 8 The CC section view is composed of Fig. 9 It can be seen that the eccentricity between every two laser light sources and the corresponding lenses in zone 2 is different, and the eccentricity between the laser light source in zone 2 and the corresponding lens is also different from the eccentricity of any laser light source in zones 4, 6, 8, 10 and 12. Fig.10 The far-field light spot finally formed by area 1, area 2, area 3, area 4 ... area 12 is different from the far-field light spot formed by area 1 and any area in area 2, area 3 ... area 12. That is to say, in the specific implementation, if the far-field light spot is to be formed as follows Fig.10 The target far-field light spot is divided into 12 areas, so that each area is a target far-field sub-spot, and the 12 light-emitting areas of the laser light source array are one-to-one with the 12 areas of the target far-field light spot, and the far-field light spot formed by each light-emitting area of ​​the laser light source array is consistent with the corresponding target far-field sub-spot to achieve depth measurement.

[0074] In addition, refer to Figure 8 Each light-emitting area has a corresponding power supply unit 8, which is used to light up and extinguish all laser light sources in the corresponding light-emitting area, and multiple power supply units 8 are connected in parallel.

[0075] The solution provided in the embodiment of the present application can light up only one light-emitting area at a time when performing long-distance ranging. After measuring the distance through the laser light source in the light-emitting area, the laser light source in another light-emitting area is lit, and finally two-dimensional scanning and lighting are achieved.

[0076] In addition, there are two structures for realizing two-dimensional scanning. The first one is that there are multiple laser light sources, and the multiple laser light sources are arranged in two dimensions, and all the laser light sources are all lit or extinguished at once by the power supply unit to realize two-dimensional scanning; the second one is that the laser light sources are arranged in a linear or dotted manner, and the laser light sources arranged in a dotted or linear manner are driven by a mechanical scanner to move in a two-dimensional direction to realize two-dimensional scanning. Although the first structure can quickly complete the two-dimensional scanning, since all the laser light sources are lit or extinguished each time, the brightness of the laser light source is insufficient, and thus long-distance ranging cannot be realized; the number of laser light sources in the second structure is less than the number of laser light sources in the first structure, but the laser light source is driven to move by a mechanical scanner, so that the brightness of the laser light source in the second structure is higher than that of the first structure, so as to realize long-distance ranging, but the mechanical scanner set up obviously increases the size of the entire light emitting component.

[0077] The advantage of the two-dimensional scanning structure provided by the embodiment of the present application compared with the first and second types mentioned above is that compared with the first type, under the premise of realizing large-scale scanning, since only one luminous area is illuminated each time, the brightness of the laser light source will be improved. For example, if the input power of all laser light sources is 20W, there are 100 laser light sources, and when the first solution is adopted, the input current of each laser light source is 0.1A. If the solution provided by the embodiment of the present application is adopted, the laser light source is divided into 10 areas, and each area has 10 laser light sources. Then, each time it is lit, the input current of each laser light source is 1A, which significantly improves the brightness of the laser light source. Therefore, compared with the first scanning structure, long-distance ranging can be achieved, and power consumption is effectively reduced. Compared with the second type, there is no need to set up a mechanical scanner, which reduces the size and effectively reduces the manufacturing cost.

[0078] The connection relationship between the laser light source 2 and the substrate 1 is explained by the following two embodiments.

[0079] The laser light source described below includes a cathode electrode layer 201 , an N-type confinement layer 202 , an active layer 203 , a P-type confinement layer 204 and an anode electrode layer 205 . Of course, in addition to these structures, structures having other functions are also included.

[0080] Embodiment 1, refer to Fig.13The substrate 1 has a first surface A1 and a second surface A2 relative to each other; a cathode electrode layer 201 is arranged on the second surface A2, an N-type restriction layer 202, an active layer 203, a P-type restriction layer 204 and an anode electrode layer 205 are stacked from bottom to top on the first surface A1, a lens is arranged on one side of the first surface A1, and a light emitting surface of the lens is opposite to the first surface A1, and the substrate is made of a conductive material.

[0081] That is to say, the anode electrode layer 205 and the cathode electrode layer 201 of the laser light source 2 are located on two sides of the substrate 1 , that is, the positive and negative electrode layers are on different surfaces.

[0082] In some embodiments, reference Fig.14 The light emitting component also includes a circuit board 4, on which a driving circuit (not shown) is arranged, the cathode electrode layer 201 is electrically connected to the cathode pin of the driving circuit through a welding structure, and the anode electrode layer 205 is electrically connected to the anode pin of the driving circuit through a connecting wire 7.

[0083] Because the cathode electrode layer 201 faces the circuit board 4, the cathode electrode layer can be connected to the driving circuit on the circuit board through a welding structure. Because the anode electrode layer 205 is located on the first surface side of the substrate, the anode electrode layer is connected to the driving circuit through a connecting wire.

[0084] Example 2, refer to Fig.15 The substrate 1 is a light-transmitting substrate, and the substrate 1 has a first surface A1 and a second surface A2 opposite to each other. An N-type restriction layer 202, an active layer 203 and a P-type restriction layer 204 are stacked from bottom to top on the first surface A1. A cathode electrode layer 201 is also arranged on the first surface A1, and an anode electrode layer 205 is arranged on the P-type restriction layer 204. The lens is arranged on one side of the second surface A2, and the light-emitting surface of the lens is opposite to the second surface. In addition, the substrate is made of a conductive material.

[0085] That is to say, the anode electrode layer 205 and the cathode electrode layer 201 of the laser light source 2 are located on the same side of the substrate 1 , that is, the positive and negative electrode layers are coplanar.

[0086] In order to improve the light transmittance of the substrate, an anti-reflection film may be provided on the second surface of the substrate.

[0087] In some embodiments, reference Fig.16 The light emitting component also includes a circuit board 4, on which a driving circuit (not shown) is arranged, the anode electrode layer 205 is electrically connected to the anode pin of the driving circuit through a first welding structure, and the cathode electrode layer 201 is electrically connected to the cathode pin of the driving circuit through a second welding structure.

[0088] The technical effect achieved by the technical solution provided in the second embodiment is as follows: since the anode electrode layer 205 and the cathode electrode layer 201 of the laser light source 2 are located on the first surface side of the substrate 1, and since the first surface of the substrate faces the circuit board 4, the anode electrode layer and the cathode electrode layer can be electrically connected to the corresponding anode pin and cathode pin of the driving circuit through the welding structure. Compared with the connection method using connecting wires in the first embodiment, the operation process is simplified, and the size of the entire light emitting component in the height direction (such as Fig.16 H direction) so that the entire optical transmission component meets the requirements of miniaturization design.

[0089] When using reference Fig.11 and Fig.12 When a light emitting component is formed, the first surface of the substrate 1 having the N-type confinement layer, the active layer, the P-type confinement layer and the anode electrode layer is covered with a light-transmitting cover layer 6, and the lens 3 is formed on a side of the light-transmitting cover layer 6 away from the first surface. By covering the light-transmitting cover layer on the first surface having the laser light source, so that the lens is formed on the side of the light-transmitting cover layer away from the first surface, the connection strength of the lens is effectively guaranteed.

[0090] In addition, the material of the light-transmitting cover layer 6 can be a light-transmitting material such as semiconductor, organic matter, etc.

[0091] The active layer 203 has a micro-cavity structure of the micron scale, and the N-type confinement layer 202 and the P-type confinement layer 204 are both distributed Bragg reflectors. The laser light source 2 formed in this way is a vertical cavity surface emitting laser (VCSEL). Because the vertical cavity surface emitting laser is small in size, has a circular output light spot, single longitudinal mode output, a small threshold current, a low price, and is easy to integrate, and the divergence angle of the vertical cavity surface emitting laser is smaller than that of the light-emitting diode (LED), the emission wavelength of 850nm or 940nm is more uniform, the spectrum width is narrower, and the resistance to stray light interference is strong. The performance of the vertical cavity surface emitting laser in realizing 3D recognition and ranging is far superior to that of LED.

[0092] The present application embodiment also provides another laser light source 2, such as Fig.17a , Fig.17b and Fig.17cAs shown, the laser light source includes an N-type confinement layer 202 and a P-type confinement layer 204 relative to each other, and an active layer 203 located between the N-type confinement layer 202 and the P-type confinement layer 204. A grating structure 206 is arranged in the P-type confinement layer 204. The grating structure 206 is used to provide feedback on the light transmission direction to realize a horizontal resonant cavity parallel to the active layer 203. A waveguide 208 is formed on the side of the P-type confinement layer 204 away from the active layer 203. The waveguide 208 is used to provide lateral light field limitation. The horizontal resonant cavity is provided with a reflective mirror 207 formed by etching or corrosion at the positions of the light inlet and the light outlet of the waveguide 208. The reflective mirror 207 can totally reflect the light output from the waveguide 208 to emit light.

[0093] For example, refer to Fig.17b The substrate 1 is light-transmissive, the laser light source is located on the first surface A1 of the substrate, and the reflective mirror 207 can emit light from the second surface A2 of the substrate 1. The inclination angle α of the reflective mirror 207 can be 45°.

[0094] For another example, refer to Fig.17d , the laser light source is located on the first surface A1 of the substrate, compared Fig.17b , the reflective mirror surface 207 can emit the light toward the first surface A1, Fig.17b and Fig.17d The difference is that the light can be emitted from the second surface A2 or from the first surface A1 by setting the inclination angle of the reflective mirror surface 207 differently. The inclination angle α of the reflective mirror surface 207 can be 135°.

[0095] The laser light source provided in this embodiment can realize not only short-wavelength transmission but also long-wavelength transmission, for example, a wavelength of 1550 nm.

[0096] Fig.17a , Fig.17b and Fig.17c In the laser light source structure shown, in order to increase the transmittance of light from the substrate, an anti-reflection film may be provided on the second surface of the substrate.

[0097] The structure of the waveguide provided in this embodiment may be a rectangular waveguide or a ridge waveguide.

[0098] In some embodiments, the distance between every two adjacent waveguides is greater than or equal to 8 μm. The distance between every two adjacent reflection cavities is 50 μm or 100 μm.

[0099] The substrate material may be a semiconductor material such as InP or GaAs, and the active region material may be a semiconductor material such as InGaAsP, InGaAs, AlGaAs, etc.

[0100] If adopted Fig.17a , Fig.17b and Fig.17c In the case of the laser light source shown, the anode electrode layer of the laser light source is arranged on the P-type confinement layer, and the cathode electrode layer is arranged on the first surface of the substrate. In other words, the anode electrode layer and the cathode electrode layer of the laser light source 2 of this structure are located on the same side of the substrate, that is, the positive and negative electrode layers are coplanar.

[0101] If adopted Fig.17d In the case of the laser light source shown, the anode electrode layer of the laser light source is arranged on the P-type confinement layer, and the cathode electrode layer is arranged on the second surface of the substrate. In other words, the anode electrode layer and the cathode electrode layer of the laser light source 2 of this structure are located on both sides of the substrate, that is, the positive and negative electrode layers are on different surfaces.

[0102] There are many types of connection structures between the lens 3 and the substrate 1, which are described below using two embodiments.

[0103] Embodiment 1, refer to Figure 2 and Figure 6 , the lens 3 is integrally formed with the substrate 1. For example, Figure 2 As shown, when the laser light source 2 is located on the first surface of the substrate 1 , the lens 3 can be directly formed on the second surface of the substrate 1 .

[0104] Example 2, refer to Fig.18 , the lens 3 is connected to the substrate 1 through a metal bonding structure 5.

[0105] The lens 3 is connected to the substrate 1 through the above two embodiments, and the technical effects that can be achieved are: compared with the bonding method of the one-piece molding and metal bonding structure, the connection strength between the lens and the substrate can be improved; in particular, when the eccentric distance between the lens and the laser light source is used to achieve the change of the divergence angle, and the connection structure of the one-piece molding or metal bonding structure has greater mechanical strength, compared with the prior art, the detector for detecting whether the light diffuser is detached is omitted. Therefore, the light emitting component provided in the embodiment of the present application not only ensures the change of the divergence angle, but also simplifies the structure of the entire light emitting component, thereby realizing a miniaturized design.

[0106] In specific implementation, multiple light emitting components may be required. There are two embodiments for implementing multiple light emitting components. Fig.19 , the substrate on which the multiple laser light sources are arranged is split into multiple sub-substrates, and the lens is split into multiple sub-lenses, and then each sub-lens and the sub-substrate are metal-bonded to form multiple light emitting components. Fig. 20 The lens and a substrate provided with a plurality of laser light sources are connected via a metal bonding structure, and then the substrate and the lens connected as one are cleaved to form a plurality of light emitting components.

[0107] In a second aspect, the present application also provides a method for preparing the light emitting component described in the first aspect, the method comprising:

[0108] Determining the eccentricity between the laser light source and the lens based on the target divergence angle of the light emitting assembly and the divergence angle of the laser light source;

[0109] A laser light source array is formed on a substrate, and then a lens array is arranged according to the eccentricity to obtain a light emitting component in which the laser light source array and the lens array are arranged eccentrically.

[0110] In the specific implementation, the final target divergence angle must be determined first, and then the eccentricity between the laser light source and the lens is determined based on the divergence angle of the laser light source itself. The eccentricity may be zero or greater than zero, and the specific eccentricity size also needs to be determined based on the size of the target divergence angle; then a laser light source array is manufactured on the substrate; and then a lens array is set on the light output side of the laser light source array according to the determined eccentricity to obtain a light emitting component in which the laser light source array and the lens array are eccentrically arranged.

[0111] Among them, when it is necessary to prepare Figure 2 When the light emitting assembly shown in FIG. 1 is used, a lens array is obtained by photolithography on the surface of the substrate 1 opposite to the laser light source array according to the determined eccentricity, or by referring to Fig.18 , the lens array is connected to the substrate by using a metal bonding structure 5. Fig.11 In the light emitting assembly shown, a light-transmitting cover layer 6 is deposited on the side of the substrate 1 where the laser light source array is formed, and then a lens array is photoetched on the side of the light-transmitting cover layer 6 away from the substrate according to a determined eccentricity.

[0112] In the process of manufacturing the light emitting assembly by using this preparation method, the eccentricity between the laser light source and the corresponding lens can be adjusted at any time according to the size of the target divergence angle of the light emitting assembly, so that light emitting assemblies with different target divergence angles can be obtained by using lenses of the same structure. That is, different products can be obtained by using parts of the same structure and only changing the relative position relationship of each part. Compared with the method of using parts of different structures to make different products, the manufacturing cost can be effectively reduced.

[0113] On the third aspect, the embodiments of the present application also provide a time-of-flight camera module, which includes a photosensitive component and a light emitting component provided in the above embodiments, a laser light source array is used to emit light, and the light emitted by the laser light source array passes through a lens array and is projected onto a target object, and the photosensitive component is used to receive light reflected from the target object, and based on the time difference or phase difference between the light emitted by the light emitting component and the reflected light received by the photosensitive component, the distance of the target object is measured.

[0114] Since the time-of-flight camera module includes the light emitting assembly provided in the above embodiment, the divergence angle of the light emitted from the laser light source array is increased by eccentrically arranging the laser light source array and the lens array, so that the time-of-flight camera module can obtain as large a detection range as possible, thereby improving the performance of the time-of-flight camera module. When the time-of-flight camera module is specifically prepared, if the target divergence angle is to be changed, the target divergence angle can be changed by changing the eccentric distance between the laser light source and the lens.

[0115] In a fourth aspect, an embodiment of the present application further provides a mobile terminal, which includes the time-of-flight camera module provided in the above embodiment. For example, the mobile terminal may be a mobile phone, a tablet computer or other electronic devices.

[0116] For example, when the time-of-flight camera module is used in a mobile phone, the divergence angle is increased by eccentrically arranging the laser light source array and the lens array, so that the mobile phone can obtain depth information of the image within a larger field of view when taking pictures. In addition, compared with the existing method of increasing the divergence angle by using a light diffuser, the time-of-flight camera module in the existing mobile phone, in addition to the light diffuser, also includes a detector for monitoring whether the light diffuser falls off. However, when the time-of-flight camera module provided by the embodiment of the present application, in which the lens array is integrally formed with the substrate or the lens array is connected to the substrate through a metal bonding structure, is used in a mobile phone, there is no need to set a detector, which can reduce the number of components of the mobile phone and avoid the phenomenon that the detector occupies space in the mobile phone.

[0117] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0118] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A light emitting component, used to be arranged in a time-of-flight camera module, characterized in that: The light emitting assembly comprises: substrate; A laser light source array is arranged on the substrate; A lens array is arranged on the light-emitting side of the laser light source array, and the lens array is integrally formed with the substrate; One lens in the lens array is arranged opposite to at least one laser light source in the laser light source array, the light emitting surface of the lens is a spherical surface, and at least part of the laser light sources are arranged eccentrically with the corresponding lens; The lens arranged eccentrically with respect to the laser light source is used to change the projection direction of the light beam from the corresponding laser light source, so that the lens array is used to increase or decrease the divergence angle of the light beam of the laser light source array; The laser light sources in the laser light source array and the lenses in the lens array are arranged in one-to-one correspondence; The laser light source array forms N light-emitting areas, each of which has at least two laser light sources, N is an integer greater than 1, the eccentricities of some laser light sources in every two light-emitting areas are equal, or the eccentricities of all laser light sources in every two light-emitting areas are not equal, and the far-field light spots formed by the light emitted by any two light-emitting areas through the corresponding lens array are different.

2. The light emitting assembly according to claim 1, characterized in that: Each of the light-emitting areas has a power supply unit, which is used to light up and extinguish all laser light sources in the corresponding light-emitting area, and a plurality of the power supply units are connected in parallel.

3. The light emitting assembly according to claim 1 or 2, characterized in that: The laser light source array includes a first laser light source and a second adjacent laser light source, and the lens array includes a first lens, which is arranged on the light exit side of the first laser light source and the light exit side of the second laser light source, the eccentricity between the first laser light source and the first lens is a first eccentricity, the eccentricity between the second laser light source and the first lens is a second eccentricity, and the first eccentricity is not equal to the second eccentricity.

4. The light emitting assembly according to claim 1 or 2, characterized in that: The substrate is made of a light-transmitting conductive material, and has a first surface and a second surface opposite to each other; The laser light source comprises an N-type confinement layer, an active layer, a P-type confinement layer, an anode electrode layer and a cathode electrode layer, wherein the N-type confinement layer, the active layer, the P-type confinement layer and the anode electrode layer are stacked on the first surface from bottom to top, and the cathode electrode layer is also arranged on the first surface; The lens array is arranged on one side of the second surface, and the light emitting surface of the lens is opposite to the second surface.

5. The light emitting assembly according to claim 4, characterized in that: It also includes a circuit board, on which a driving circuit is arranged, the cathode electrode layer is electrically connected to the cathode pin of the driving circuit through a first welding structure, and the anode electrode layer is electrically connected to the anode pin of the driving circuit through a second welding structure.

6. The light emitting assembly according to claim 1 or 2, characterized in that: The substrate is made of a conductive material and has a first surface and a second surface opposite to each other; The laser light source comprises an N-type confinement layer, an active layer, a P-type confinement layer, an anode electrode layer and a cathode electrode layer, wherein the N-type confinement layer, the active layer, the P-type confinement layer and the anode electrode layer are stacked from bottom to top on the first surface, and the cathode electrode layer is arranged on the second surface; The lens array is arranged on one side of the first surface, and the light emitting surface of the lens is opposite to the first surface.

7. The light emitting assembly according to claim 6, characterized in that: It also includes a circuit board, on which a driving circuit is arranged, the cathode electrode layer is electrically connected to the cathode pin of the driving circuit via a welding structure, and the anode electrode layer is electrically connected to the anode pin of the driving circuit via a connecting wire.

8. The light emitting assembly according to claim 6, characterized in that: The first surface on which the N-type confinement layer, the active layer, the P-type confinement layer, and the anode electrode layer are formed is covered with a light-transmitting cover layer, and the lens is formed on a surface of the light-transmitting cover layer opposite to the first surface.

9. A time-of-flight camera module, characterized in that: include: A light emitting component, wherein the light emitting component is a light emitting component as claimed in any one of claims 1 to 8, wherein the laser light source array is used to emit light, and the light emitted by the laser light source array can pass through the lens array and be projected onto a target object; A photosensitive component is used to receive the light reflected from the target object and measure the distance of the target object based on the time difference or phase difference between the light emitted by the light emitting component and the reflected light received by the photosensitive component.

10. A mobile terminal, characterized in that: Comprising a time-of-flight camera module as described in claim 9.

Images