Light emitting and receiving module for distance measurement and distance measurement device

Abstract

To provide a light emitting and receiving module for distance measurement and a distance measurement device in which each element can be suitably arranged.SOLUTION: A light emitting and receiving module 2 includes: a wiring board 10 that has a main surface 11; a semiconductor laser unit 20 that is provided on the main surface 11 and emits laser light L from an end surface 22a that intersects the main surface 11; a reflection block 30 being the reflection block 30 that is provided on the main surface 11, has a reflective surface 31 inclined relative to the main surface 11 and reflects the laser light L from the semiconductor laser unit 20 to a side opposite to the wiring board 10; a collimating lens 40 that is provided on the main surface 11 and positioned between the semiconductor laser unit 20 and the reflection block 30; and a light receiving sensor 50 that is provided on the main surface 11 and detects the laser light L emitted from the semiconductor laser unit 20, transmitted through the collimating lens 40, reflected by the reflective surface 31 of the reflection block 30, and subsequently reflected from a target object.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a distance measuring light emitting and receiving module and a distance measuring device. [Background technology]

[0002] Patent Document 1 describes a lidar sensor that measures the distance to an object by a time-of-flight (TOF) method. This lidar sensor includes a light source and a detector mounted on a board. A lens assembly is disposed above the light source and the detector, and a light beam emitted from the light source passes through the lens assembly, is reflected by the object, and enters the detector. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-525426 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned apparatus is required to meet various requirements, such as improved yield and high accuracy in the placement of each element.

[0005] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a distance measuring light emitting and receiving module and a distance measuring device in which each element can be suitably arranged. [Means for solving the problem]

[0006] The distance measurement light projecting and receiving module of the present invention is [1] "a distance measurement light projecting and receiving module comprising: a wiring board having a main surface; a semiconductor laser unit provided on the main surface and emitting laser light from a side surface intersecting the main surface; a reflection block provided on the main surface, the reflection block having a reflection surface inclined with respect to the main surface and reflecting the laser light from the semiconductor laser unit to the opposite side to the wiring board; a collimating lens provided on the main surface and positioned between the semiconductor laser unit and the reflection block; and a light receiving sensor provided on the main surface for detecting the laser light emitted from the semiconductor laser unit, passing through the collimating lens, reflected by the reflection surface of the reflection block, and then reflected by an object."

[0007] In this distance measuring light projecting and receiving module, each element of the semiconductor laser unit, the reflection block, the collimating lens, and the light receiving sensor are provided on the main surface of the wiring board. This can improve the yield, for example, compared to a case where the semiconductor laser unit and the collimating lens are provided on one board and the light receiving sensor is provided on another board, and these boards are combined to configure the light projecting and receiving module. Also, the semiconductor laser unit is provided on the main surface so as to emit laser light from a side surface intersecting with the main surface, and the laser light from the semiconductor laser unit is reflected by the reflection block to the opposite side of the wiring board. This makes it possible to provide the collimating lens on the main surface. As a result, for example, compared to a case where a separate collimating lens is provided at a position away from the wiring board, the collimating lens can be positioned with high accuracy. Also, the laser light from the semiconductor laser unit is reflected by the reflection block to the opposite side of the wiring board. This can suppress attenuation of the laser light in the wiring board, and ensure the intensity of the laser light, for example, compared to a case where the laser light from the semiconductor laser unit is reflected by the reflection block to the side of the wiring board and transmitted through the wiring board to be emitted to the outside. In this manner, according to this distance measuring light emitting / receiving module, each element can be suitably arranged.

[0008] The distance measurement light emitting / receiving module of the present invention may be [2] "the distance measurement light emitting / receiving module according to [1], in which the reflection block is located between the collimating lens and the light receiving sensor." In this case, the distance between the semiconductor laser unit and the light receiving sensor can be secured long, and the heat generated in the semiconductor laser unit can be prevented from affecting the light receiving sensor. In addition, the semiconductor laser unit may emit laser light not only to the collimating lens side but also to the opposite side of the collimating lens. For example, if the light receiving sensor is located on the opposite side of the collimating lens with respect to the semiconductor laser unit, there is a concern that the light emitted to the opposite side of the collimating lens may be detected as stray light by the light receiving sensor. In contrast, in the distance measurement light emitting / receiving module of [2], the reflection block is located between the semiconductor laser unit and the light receiving sensor, so that such a situation can be prevented from occurring. In addition, the reflection block can also block light from outside the distance measurement light emitting / receiving module from entering the light receiving sensor.

[0009] The distance measurement light emitting / receiving module of the present invention may be [3] "the distance measurement light emitting / receiving module according to [1] or [2], in which the reflection block is configured as a separate member from the wiring board and fixed to the main surface." For example, if the reflection block and the wiring board are configured as a common member, the amount of processing required to form the reflection block increases. In addition, the reflection block cannot be formed from a material other than the wiring board. In contrast, in the light emitting / receiving module of [3], for example, the reflection block can be formed from a material other than the wiring board, making it possible to select a material and processing method suitable for the reflection block, thereby improving the forming accuracy and characteristics of the entire distance measurement light emitting / receiving module. In addition, for example, when the reflection block and the wiring board are configured as a common member, when applying a metal coating to the reflection block, great care must be taken to prevent the metal coating from being conductive with elements on the main surface. In contrast, in the light emitting / receiving module of [3], the reflection block is configured as a separate member from the wiring board, so such care is not required and processing can be facilitated.

[0010] The distance measuring light emitting and receiving module of the present invention may be [4] "the distance measuring light emitting and receiving module according to any one of [1] to [3], in which the wiring board and the reflecting block are formed of different materials." In this case, it becomes possible to select a material and processing method suitable for the reflecting block, and it is possible to improve the forming accuracy and characteristics of the entire distance measuring light emitting and receiving module.

[0011] The distance measurement light emitting / receiving module of the present invention may be [5] "the distance measurement light emitting / receiving module according to any one of [1] to [4], in which the reflection block has a flat surface on the side opposite to the wiring board." In this case, for example, when the reflection block is fixed to the wiring board, the reflection block can be easily picked up and placed at a predetermined position by adsorbing the flat surface with a pickup device.

[0012] The distance measuring light emitting and receiving module of the present invention may be [6] "the distance measuring light emitting and receiving module according to any one of [1] to [5], in which the reflection block is formed of reflectively coated silicon." In this case, the reflection block can be formed with high precision.

[0013] The distance measuring light emitting and receiving module of the present invention may be [7] "the distance measuring light emitting and receiving module according to any one of [1] to [6], including a plurality of the semiconductor laser units." In this case, the total intensity of the laser light can be increased.

[0014] The distance measuring light emitting / receiving module of the present invention may be [8] "the distance measuring light emitting / receiving module according to [7], comprising a plurality of the reflection blocks, each of which corresponds to the plurality of semiconductor laser units one-to-one and reflects the laser light from the corresponding semiconductor laser units." In this case, material costs can be reduced compared to the case where one reflection block is provided corresponding to the plurality of semiconductor laser units.

[0015] The distance measurement light emitting / receiving module of the present invention may be [9] "the distance measurement light emitting / receiving module according to [7], in which the reflection block reflects the laser light from the plurality of semiconductor laser units." In this case, since it is only necessary to provide one reflection block corresponding to the plurality of semiconductor laser units, the reflection block can be easily and accurately fixed to the wiring board.

[0016] The distance measuring light emitting / receiving module of the present invention may be

[10] "a distance measuring light emitting / receiving module according to any one of [7] to [9], comprising a plurality of collimating lenses, each of which corresponds to the semiconductor laser units in a one-to-one relationship, and collimates the laser light from the corresponding semiconductor laser units." For example, when one collimating lens is provided corresponding to a plurality of semiconductor laser units, even when only one semiconductor laser unit is operating, the laser light from the semiconductor laser unit may be reflected in the collimating lens, causing the entire collimating lens to emit light. In contrast, the distance measuring light emitting / receiving module of

[10] can prevent such a situation from occurring.

[0017] The distance measurement light emitting / receiving module of the present invention may be

[11] "the distance measurement light emitting / receiving module according to any one of [7] to [9], wherein the collimating lens collimates the laser light from the plurality of semiconductor laser units." In this case, since it is only necessary to provide one collimating lens corresponding to the plurality of semiconductor laser units, the collimating lens can be easily and accurately fixed to the wiring board.

[0018] The distance measurement light emitting / receiving module of the present invention may be

[12] "the distance measurement light emitting / receiving module according to any one of [1] to

[11] , in which a resin material is disposed between the collimating lens and the semiconductor laser unit." In this case, for example, by making the refractive index of the resin material larger than the refractive index of air and equal to or smaller than the refractive index of the collimating lens, it is possible to suppress reflection of the laser light when it is incident on the collimating lens. When the refractive index of the resin material is made larger than the refractive index of air, it is also possible to reduce the spread angle of the laser light from the semiconductor laser unit.

[0019] The distance measuring light emitting / receiving module of the present invention may be

[13] "the distance measuring light emitting / receiving module according to any one of [1] to

[12] , in which a concave portion recessed toward the semiconductor laser portion is formed on the surface of the collimating lens opposite to the semiconductor laser portion." In this case, the intensity distribution of the laser light can be adjusted to a desired shape by the collimating lens.

[0020] The distance measurement light emitting / receiving module of the present invention may be

[14] "the distance measurement light emitting / receiving module according to any one of [1] to

[13] , in which the semiconductor laser section has a submount substrate and a laser element mounted on the submount substrate, and the submount substrate is mounted on the main surface of the wiring substrate." In this case, it is possible to suppress the heat generated in the laser element from affecting the light receiving sensor. In addition, since the submount substrate is disposed between the laser element and the wiring substrate, it is possible to suppress the laser light emitted from the laser element from interfering with the wiring substrate before entering the collimator lens. In addition, compared to the case where the laser element is directly provided on the wiring substrate, for example, a burn-in test can be performed before fixing to the wiring substrate, so that only the semiconductor laser section that has passed the burn-in test can be used.

[0021] The distance measurement light emitting / receiving module of the present invention may be

[15] "a distance measurement light emitting / receiving module according to any one of [1] to

[14] , further comprising a bandpass filter arranged on the opposite side of the light receiving sensor from the wiring board, the bandpass filter being supported by a pair of supports provided on the main surface so as to sandwich the light receiving sensor." In this case, light of wavelengths other than the wavelength to be detected can be blocked by the bandpass filter, and detection efficiency can be improved. In addition, since the bandpass filter is supported by a pair of supports provided on the main surface so as to sandwich the light receiving sensor, for example, it is possible to suppress interference of the bandpass filter with a wire connecting the light receiving sensor to the wiring board.

[0022] The distance measuring light emitting and receiving module of the present invention may be

[16] "the distance measuring light emitting and receiving module according to any one of [1] to

[14] , further comprising a layered bandpass filter formed on the light receiving section of the light receiving sensor." In this case, light of wavelengths other than the wavelength to be detected can be blocked by the bandpass filter, and detection efficiency can be improved. In addition, since the bandpass filter is formed on the light receiving section of the light receiving sensor, the bandpass filter can be well formed.

[0023] The distance measuring light emitting and receiving module of the present invention may be

[17] "the distance measuring light emitting and receiving module according to any one of [1] to

[14] further comprising a bandpass filter placed on the light receiving section of the light receiving sensor." In this case, light of wavelengths other than the wavelength to be detected can be blocked by the bandpass filter, thereby improving detection efficiency.

[0024] The distance measuring device of the present invention is

[18] "a distance measuring device comprising a distance measuring light emitting and receiving module according to any one of [1] to

[17] , and a control unit that calculates the distance to the target object based on the detection result of the laser light by the light receiving sensor." With this distance measuring device, for the reasons described above, each element can be suitably arranged in the distance measuring light emitting and receiving module. Effect of the Invention

[0025] According to the present invention, it is possible to provide a distance measuring light emitting and receiving module and a distance measuring device in which each element can be suitably arranged. [Brief description of the drawings]

[0026] [Figure 1] 1 is a configuration diagram of a distance measuring device according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of the light emitting and receiving module as viewed from the front side. [Diagram 3] FIG. 2 is a perspective view of the light emitting and receiving module as seen from the rear side. [Figure 4] FIG. 2 is a perspective view of a semiconductor laser portion as viewed from the front side. [Diagram 5] FIG. 2 is a perspective view of the semiconductor laser portion as seen from the back side. [Figure 6] FIG. 2 is a diagram for explaining the arrangement of each element. [Figure 7] FIG. 13 is a perspective view of a light emitting and receiving module according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same or corresponding elements are designated by the same reference numerals, and redundant description will be omitted.

[0028] 1, the distance measuring device 1 includes a light emitting / receiving module 2 (light emitting / receiving module for distance measurement) and a control unit 3. In the distance measuring device 1, a laser light L is emitted (projected) from a semiconductor laser unit 20 of the light emitting / receiving module 2. The laser light L is reflected by an object S and then detected (received) by a light receiving sensor 50 of the light emitting / receiving module 2.

[0029] The control unit 3 calculates the distance from the distance measuring device 1 (light emitting and receiving module 2) to the object S based on the detection result of the laser light L by the light receiving sensor 50. In this example, the distance measuring device 1 is a LiDAR (Light Detection And Ranging) device that measures the distance to the object S by a TOF method, and the control unit 3 calculates the distance to the object S based on the time of flight of the laser light L (the time from when it is emitted from the semiconductor laser unit 20 to when it is detected by the light receiving sensor 50). The control unit 3 is configured by, for example, a microcomputer provided on a circuit board. In the distance measuring device 1, the light emitting and receiving module 2 is mounted on the circuit board, and the control unit 3 is electrically connected to the light emitting and receiving module 2.

[0030] As shown in FIG. 2, the light emitting / receiving module 2 includes a wiring board 10, a plurality of semiconductor laser units 20, a plurality of reflecting blocks 30, a plurality of collimating lenses 40, a plurality of light receiving sensors 50, and a band pass filter 60. In this example, the semiconductor laser units 20, the reflecting blocks 30, the collimating lenses 40, and the light receiving sensors 50 are provided in fours (the same number). The following description will be made with reference to the X direction, the Y direction (direction perpendicular to the X direction), and the Z direction (direction perpendicular to the X direction and the Y direction) shown in each figure. In FIG. 2, for ease of understanding, the sealing resin 28 of the semiconductor laser unit 20, the collimating lenses 40, and the band pass filter 60 are indicated by two-dot chain lines. This is the same in FIG. 7 described later, and in FIG. 3 and FIG. 4 described later.

[0031] The wiring board 10 is formed in a rectangular plate shape having long sides parallel to the X direction, for example, and has a main surface 11 and a main surface 12. The main surface 11 is a surface on one side in the Z direction, and the main surface 12 is a surface (back surface) opposite to the main surface 11. The main surfaces 11 and 12 are flat surfaces perpendicular to the Z direction, for example. The wiring board 10 is, for example, a glass epoxy board or a ceramic board. When the wiring board 10 is a ceramic board, the thermal conductivity of the ceramic board is higher than that of air, so that the heat generated in the semiconductor laser section 20 can be efficiently dissipated. The main surface 11 is provided with an alignment mark 18 formed by, for example, gold plating. The alignment mark 18 is used as a reference for positioning when the semiconductor laser section 20, the reflection block 30, the collimator lens 40, and the light receiving sensor 50 are fixed to the main surface 11 by die bonding.

[0032] The semiconductor laser section 20 is provided on the main surface 11, and emits laser light L along a direction parallel to the main surface 11. In this example, the semiconductor laser section 20 emits laser light L along the Y direction. As shown in Fig. 4, the semiconductor laser section 20 has a chip-on-board (COB) structure, and includes a submount substrate 21 (board) and a laser element 22 (chip) mounted on the submount substrate 21. The submount substrate 21 is formed in the shape of a rectangular plate (rectangular parallelepiped) having long sides parallel to the X direction, for example.

[0033] The laser element 22 is, for example, an edge-emitting semiconductor laser that emits laser light L from an end face 22a (side face) in the Y direction. The end face 22a is a side face that intersects with the main surface 11 of the wiring board 10, and in this example, is a flat surface perpendicular to the main surface 11 (perpendicular to the Y direction). The end face 22a may intersect with the main surface 11 at an angle other than perpendicular. The laser element 22 is, for example, a pulsed laser diode, and emits laser light L, which is pulsed light. The laser element 22 is electrically connected to an anode electrode 23 and a cathode electrode 24 provided on the front surface 21a of the submount substrate 21 so as to sandwich the laser element 22 in the X direction, via a plurality of wires 25 (four in this example). The laser element 22 is also disposed on the submount substrate 21 via a ground electrode 26, and is electrically connected to the ground electrode 26.

[0034] A pair of insulating members 27 are further provided on the surface 21a of the submount substrate 21, located between the anode electrode 23 and the ground electrode 26 and between the cathode electrode 24 and the ground electrode 26, respectively. The pair of insulating members 27 electrically insulate the anode electrode 23 and the ground electrode 26 and the cathode electrode 24 and the ground electrode 26, respectively. As in the example of FIG. 4, the area of ​​the surface 21a of the submount substrate 21 other than the area where the electrodes (the anode electrode 23, the cathode electrode 24, and the ground electrode 26) and the insulating members 27 are arranged may be exposed, or the entire area of ​​the surface 21a other than the area where the electrodes are arranged may be covered by the insulating member 27.

[0035] A sealing resin 28 (mold resin) is further provided on the surface 21a of the submount substrate 21. The sealing resin 28 is provided, for example, on the entire surface 21a, and covers and seals the laser element 22, the anode electrode 23, the cathode electrode 24, the ground electrode 26, and the insulating member 27. The sealing resin 28 is formed, for example, in a rectangular parallelepiped shape, and the semiconductor laser portion 20 is formed in a rectangular parallelepiped shape as a whole.

[0036] As shown in FIG. 5, a plurality of electrodes 29 (six in this example) are provided on the surface 21b of the submount substrate 21. The surface 21b is the surface (rear surface) opposite to the surface 21a. Each electrode 29 is formed, for example, in a circular shape. In this example, the plurality of electrodes 29 are arranged in three rows along the X direction, each row consisting of two electrodes 29 aligned along the Y direction. The two electrodes 29A aligned in the Y direction are arranged so as to overlap the anode electrode 23 in the Z direction, and are electrically connected to the anode electrode 23. The two electrodes 29B aligned in the Y direction are arranged so as to overlap the ground electrode 26 in the Z direction, and are electrically connected to the ground electrode 26. The two electrodes 29C aligned in the Y direction are arranged so as to overlap the cathode electrode 24 in the Z direction, and are electrically connected to the cathode electrode 24. These electrodes 29 are connected by solder bumps to a plurality of electrodes 13 (six in this example) (see FIG. 6) provided on the main surface 11 of the wiring board 10, whereby the semiconductor laser section 20 is mounted on the wiring board 10. The electrodes 13 are arranged corresponding to the arrangement of the electrodes 29. The semiconductor laser section 20 is fixed to the main surface 11 at the surface having the largest area (surface 21b of the submount substrate 21 in this example).

[0037] The wiring board 10 has through holes formed therein at positions overlapping with the electrodes 13 in the Z direction, penetrating the wiring board 10 along the Z direction. The electrodes 13 are electrically connected to electrode pads 14 (see FIG. 3) provided on the main surface 12 of the wiring board 10 via the through holes. In this example, three electrode pads 14 are provided corresponding to one laser element 22, for a total of twelve electrode pads 14. The twelve electrode pads 14 are arranged at equal intervals along the X direction.

[0038] The three electrode pads 14 corresponding to one laser element 22 are electrically connected to the anode electrode 23, the cathode electrode 24, and the ground electrode 26 of the corresponding laser element 22. More specifically, the electrodes 29A, 29B, and 29C are electrically connected to the electrode pads 14 via the electrodes 13, respectively, and thus the anode electrode 23, the cathode electrode 24, and the ground electrode 26 are each electrically connected to the electrode pads 14. At least three electrodes 29 are required to electrically connect the anode electrode 23, the cathode electrode 24, and the ground electrode 26 to the electrode pads 14, but by providing six electrodes 29 as in the example of FIG. 5, the stability of the electrical connection and the heat dissipation can be improved.

[0039] The reflection block 30 is provided on the main surface 11 of the wiring board 10. In this example, the four reflection blocks 30 are arranged in a line at equal intervals along the X direction. The four reflection blocks 30 correspond one-to-one with the four semiconductor laser units 20, and face the corresponding semiconductor laser units 20 in the Y direction with the collimator lens 40 interposed therebetween. The four reflection blocks 30 also correspond one-to-one with the four collimator lenses 40 and one-to-one with the four light receiving sensors 50, and are located between the corresponding collimator lens 40 and the corresponding light receiving sensor 50. In other words, in this example, the corresponding semiconductor laser units 20, the collimator lenses 40, the reflection blocks 30, and the light receiving sensors 50 are arranged in this order in the Y direction.

[0040] The reflecting block 30 is a micromirror formed, for example, by wet etching a silicon material, and has a reflecting surface 31, a flat surface 32, a bottom surface 33, and side surfaces 34. The reflecting block 30 is configured as a separate member from the wiring board 10, and the bottom surface 33 is fixed to the main surface 11 of the wiring board 10 by die bonding. That is, in this example, the reflecting block 30 is not formed as a common (single) member with the wiring board 10 by integral molding. In addition, the reflecting block 30 is formed from a material different from that of the wiring board 10.

[0041] The reflecting surface 31 extends at an incline with respect to the main surface 11 of the wiring board 10. In this example, the reflecting surface 31 is inclined at 45 degrees with respect to the main surface 11. The reflecting surface 31 is provided with a reflective film (Au film) made of gold, which allows the reflecting surface 31 to reflect the laser light L. The reflective film is formed, for example, by applying a metal coating by sputtering to a silicon substrate obtained by wet etching. That is, the reflecting block 30 in this example is formed of reflectively coated silicon. The reflective film is formed, for example, on the entire flat surface 32 and a part of the bottom surface 33, and is not formed on the side surface 34 (surfaces other than the reflecting surface 31, the flat surface 32, and the bottom surface 33). The reflecting block 30 reflects the laser light L emitted from the corresponding semiconductor laser unit 20 and transmitted through the collimating lens 40 to the opposite side of the wiring board 10. In this example, the reflecting block 30 reflects the laser light L in the Z direction (the direction perpendicular to the main surface 11 of the wiring board 10). The reflective film (reflective coating) is not limited to a metal coating made of gold, but may be, for example, a metal coating made of other metal materials, or a reflective coating made of a dielectric multilayer film. The material for applying the reflective coating is not limited to silicon, but may be other materials.

[0042] The flat surface 32 is the surface of the reflecting block 30 opposite to the wiring board 10, and extends perpendicular to the Z direction (parallel to the main surface 11 of the wiring board 10). The flat surface 32 is formed in a rectangular shape having long sides parallel to the X direction, for example.

[0043] The collimating lenses 40 are provided on the main surface 11 of the wiring substrate 10. In this example, the four collimating lenses 40 are arranged in a line at equal intervals along the X direction. The four collimating lenses 40 correspond one-to-one to the four semiconductor laser units 20 and face the corresponding semiconductor laser units 20 in the Y direction. Each collimating lens 40 collimates the light from the corresponding semiconductor laser unit 20. The collimating lenses 40 are formed of, for example, glass.

[0044] A recess 41 recessed toward the semiconductor laser unit 20 is formed on the surface 40a of the collimator lens 40 opposite to the semiconductor laser unit 20. The recess 41 is formed in a semicircular shape when viewed from the Z direction. That is, the recess 41 has an inner surface that is curved in an arc shape when viewed from the Z direction. By refracting the laser light L on the curved surface in this way, the intensity distribution of the laser light L emitted from the collimator lens 40 can be adjusted to a desired shape. In this example, the laser light L emitted from the semiconductor laser unit 20 has a bihedral distribution (a shape having raised parts on both sides of the center) in which the intensity of the center is lower than the intensity of the both sides. After the laser light L passes through the collimator lens 40, the intensity distribution of the laser light L is adjusted to a Gaussian distribution. In other words, the recess 41 is formed in a shape according to the intensity distribution of the laser light L emitted from the semiconductor laser unit 20.

[0045] The collimator lens 40 is disposed away from the corresponding semiconductor laser unit 20 in the Y direction, and a resin material R is disposed between the collimator lens 40 and the semiconductor laser unit 20. The resin material R is formed of, for example, silicone. The material of the resin material R is selected so that the refractive index of the resin material R is greater than the refractive index of air and equal to or less than the refractive index of the collimator lens 40. In this embodiment, the refractive index of the resin material R is greater than the refractive index of the sealing resin 28 of the semiconductor laser unit 20 and equal to or less than the refractive index of the collimator lens 40.

[0046] The light receiving sensor 50 is provided on the main surface 11 of the wiring board 10. In this example, the four light receiving sensors 50 are arranged in a line at equal intervals along the X direction. The four light receiving sensors 50 correspond one-to-one to the four semiconductor laser units 20, and face the corresponding semiconductor laser units 20 in the Y direction via the collimator lens 40 and the reflection block 30. That is, the light receiving sensor 50 is arranged on the opposite side of the reflection block 30 to the semiconductor laser units 20. The light receiving sensor 50 is electrically connected by a wire 52 to an electrode 15 provided on the main surface 11 so as to be adjacent to the light receiving sensor 50 in the Y direction. The light receiving sensor 50 is fixed to the main surface 11 at the surface (bottom surface) with the largest area. The light receiving sensor 50 is configured by, for example, an avalanche photodiode.

[0047] The light receiving sensor 50 has, for example, a circular light receiving section 51, and detects the laser light L that is incident on the light receiving section 51 via the following path: The laser light L emitted from the semiconductor laser section 20 passes through the collimator lens 40 and travels toward the reflecting surface 31 of the reflecting block 30. The laser light L is then reflected by the reflecting surface 31 and travels toward the object S. The laser light L is then reflected by the object S and returns to the light emitting / receiving module 2. The laser light L then enters the light receiving section 51 and is detected by the light receiving sensor 50.

[0048] The bandpass filter 60 is disposed on the opposite side of the wiring board 10 with respect to the light receiving sensor 50. The bandpass filter 60 transmits light of a wavelength in a predetermined range while blocking light of wavelengths outside the range. The bandpass filter 60 is formed, for example, in a rectangular plate shape having long sides parallel to the X direction, and faces the four light receiving sensors 50 in the Z direction. The bandpass filter 60 is supported by a pair of support parts 16 provided on the main surface 11 of the wiring board 10 so as to sandwich the four light receiving sensors 50, and is separated from the four light receiving sensors 50 in the Z direction. The pair of support parts 16 are formed integrally with the wiring board 10 by, for example, integral molding, and constitute a member common to the wiring board 10. Each support part 16 is formed, for example, in a rectangular parallelepiped shape having long sides parallel to the Y direction. [Action and Effects]

[0049] In the light emitting / receiving module 2, the semiconductor laser section 20, the reflecting block 30, the collimating lens 40, and the light receiving sensor 50 are provided on the main surface 11 of the wiring board 10. This improves the yield rate compared to a case where the semiconductor laser section 20 and the collimating lens 40 are provided on one board and the light receiving sensor 50 is provided on another board, and the boards are combined to form a light emitting / receiving module. When combining the boards, it is difficult to adjust the positions between the boards, which may reduce the yield rate, whereas in the light emitting / receiving module 2, the positions of the elements can be easily adjusted. In addition, the semiconductor laser section 20 is provided on the main surface 11 so as to emit the laser light L from an end surface 22a intersecting with the main surface 11, and the laser light L from the semiconductor laser section 20 is reflected by the reflecting block 30 to the opposite side of the wiring board 10. This makes it possible to provide the collimating lens 40 on the main surface 11. As a result, the collimator lens 40 can be positioned with higher accuracy than, for example, a case where a separate collimator lens 40 is positioned away from the wiring board 10. Also, the laser light L from the semiconductor laser unit 20 is reflected by the reflection block 30 toward the opposite side of the wiring board 10. This makes it possible to suppress attenuation of the laser light L within the wiring board 10 and ensure the intensity of the laser light L, compared to, for example, a case where the laser light L from the semiconductor laser unit 20 is reflected by the reflection block 30 toward the wiring board 10 and transmitted through the wiring board 10 to be emitted to the outside. In this way, according to the light emitting / receiving module 2, each element can be appropriately positioned.

[0050] The reflection block 30 is located between the collimator lens 40 and the light receiving sensor 50. This allows a long distance to be secured between the semiconductor laser unit 20 and the light receiving sensor 50, and the heat generated in the semiconductor laser unit 20 can be prevented from affecting the light receiving sensor 50. In addition, the laser light L may be emitted from the semiconductor laser unit 20 not only to the collimator lens 40 side but also to the opposite side of the collimator lens 40. For example, if the light receiving sensor 50 is disposed on the opposite side of the collimator lens 40 with respect to the semiconductor laser unit 20, there is a concern that the light emitted to the opposite side of the collimator lens 40 may be detected as stray light by the light receiving sensor 50. In contrast, in the light emitting / receiving module 2, the reflection block 30 is located between the semiconductor laser unit 20 and the light receiving sensor 50, and thus the occurrence of such a situation can be prevented. In addition, the reflection block 30 can also block light from outside the light emitting / receiving module 2 from entering the light receiving sensor 50.

[0051] The reflection block 30 is configured as a member separate from the wiring board 10 and fixed to the main surface 11. For example, if the reflection block 30 and the wiring board 10 are configured as a common member, the amount of processing required to form the reflection block 30 increases. In addition, the reflection block 30 cannot be formed from a material other than that of the wiring board 10. In contrast, in the light projecting and receiving module 2, for example, the reflection block 30 can be formed from a material other than that of the wiring board 10, making it possible to select a material and processing method suitable for the reflection block 30, and improving the forming accuracy and characteristics of the entire light projecting and receiving module 2. In addition, for example, when the reflection block 30 and the wiring board 10 are configured as a common member, when applying a metal coating to the reflection block 30, great care must be taken to prevent the metal coating from being conductive with elements on the main surface 11. In contrast, in the light projecting and receiving module 2, since the reflection block 30 is configured as a member separate from the wiring board 10, such care is not required and processing can be facilitated.

[0052] The wiring board 10 and the reflection block 30 are formed from different materials. This makes it possible to select a suitable material and processing method for the reflection block 30, thereby improving the forming accuracy and characteristics of the entire light emitting and receiving module 2.

[0053] The reflecting block 30 has a flat surface 32 on the side opposite to the wiring board 10. As a result, for example, when fixing the reflecting block 30 to the wiring board 10, the reflecting block 30 can be easily picked up and placed in a predetermined position by adsorbing the flat surface 32 with a pickup device.

[0054] The reflective block 30 is made of reflectively coated silicon, which allows the reflective block 30 to be formed with high precision.

[0055] A plurality of semiconductor laser portions 20 are provided. This makes it possible to increase the total intensity of the laser light L.

[0056] The multiple reflection blocks 30 correspond one-to-one to the multiple semiconductor laser portions 20 and reflect the laser light L from the corresponding semiconductor laser portions 20. This makes it possible to reduce material costs compared to, for example, a case in which one reflection block 30 is provided corresponding to the multiple semiconductor laser portions 20.

[0057] The multiple collimator lenses 40 correspond one-to-one to the multiple semiconductor laser units 20, and collimate the laser light L from the corresponding semiconductor laser units 20. For example, when one collimator lens 40 is provided corresponding to the multiple semiconductor laser units 20, even when only one semiconductor laser unit 20 is operating, the laser light L from that semiconductor laser unit 20 may be reflected within the collimator lens 40, causing the entire collimator lens 40 to emit light. In contrast, the light emitting / receiving module 2 can prevent such an occurrence.

[0058] A resin material R is disposed between the collimator lens 40 and the semiconductor laser unit 20. As a result, for example, by making the refractive index of the resin material R larger than the refractive index of air and equal to or smaller than the refractive index of the collimator lens 40, it is possible to suppress reflection of the laser light L when it is incident on the collimator lens 40. By making the refractive index of the resin material R larger than the refractive index of air, it is also possible to reduce the spread angle of the laser light L from the semiconductor laser unit 20.

[0059] A recess 41 recessed toward the semiconductor laser section 20 is formed on a surface 40a of the collimator lens 40 opposite to the semiconductor laser section 20. This allows the intensity distribution of the laser light L to be adjusted to a desired shape by the collimator lens 40.

[0060] The semiconductor laser section 20 has a submount substrate 21 and a laser element 22 mounted on the submount substrate 21, and is mounted on the main surface 11 of the wiring board 10 in the submount substrate 21. Since the semiconductor laser section 20 has a chip-on-board structure in this way, heat generated in the laser element 22 is less likely to be released to the outside, and the heat generated in the laser element 22 can be prevented from affecting the light receiving sensor 50. In addition, since the submount substrate 21 is disposed between the laser element 22 and the wiring board 10, it is possible to prevent the laser light L emitted from the laser element 22 from interfering with the wiring board 10 before entering the collimator lens 40. In addition, compared to the case where the laser element 22 is directly provided on the wiring board 10, for example, a burn-in test can be performed before the laser element 22 is fixed to the wiring board 10, so that only the semiconductor laser section 20 that has passed the burn-in test can be used, and the total cost can be reduced.

[0061] A bandpass filter 60 is disposed on the opposite side of the wiring board 10 with respect to the light receiving sensor 50, and the bandpass filter 60 is supported by a pair of supports 16 provided on the main surface 11 so as to sandwich the light receiving sensor 50. This allows the bandpass filter 60 to block light of wavelengths other than the wavelength to be detected, improving detection efficiency. In addition, since the bandpass filter 60 is supported by a pair of supports 16 provided on the main surface 11 so as to sandwich the light receiving sensor 50, for example, it is possible to suppress interference of the bandpass filter 60 with the wires 52 connecting the light receiving sensor 50 and the wiring board 10. [Variations]

[0062] The light emitting and receiving module 2 may be configured as in the modified example shown in Fig. 7. In this modified example, the semiconductor laser section 20 is made of a laser element 22 and does not include a submount substrate 21. That is, the semiconductor laser section 20 is configured of a laser chip (laser element 22). When the semiconductor laser section 20 is a laser chip, heat is less likely to be trapped and heat dissipation is high compared to when the semiconductor laser section 20 has a chip-on-board structure (package).

[0063] The semiconductor laser section 20 is electrically connected to the anode electrode 23 and the cathode electrode 24 provided on the main surface 11 of the wiring board 10 via a plurality of wires 25 (four in this example). The semiconductor laser section 20 is also disposed on the main surface 11 via the ground electrode 26 and is electrically connected to the ground electrode 26. The anode electrode 23, the cathode electrode 24, and the ground electrode 26 are electrically connected to the electrode pad 14 (see FIG. 3) provided on the main surface 12 of the wiring board 10 via a through hole penetrating the wiring board 10. The through hole is formed so as not to overlap the connection area with the wire 25 in the Z direction. In this example, the through hole is formed in the lower part of the anode electrode 23, the cathode electrode 24, and the ground electrode 26 on the opposite side to the collimator lens 40 in the Y direction. This makes it possible to suppress a decrease in adhesion when the wire 25 is connected, and the wire 25 can be connected well.

[0064] 7, one reflection block 30 is provided corresponding to four semiconductor laser units 20. The reflection block 30 is formed to extend along the X direction, and faces the four semiconductor laser units 20 in the Y direction via the collimator lens 40. In this case, the reflection block 30 reflects the laser light L from the four semiconductor laser units 20 by one reflection surface 31.

[0065] 7, one collimating lens 40 corresponding to four semiconductor laser portions 20 is provided. The collimating lens 40 is formed to extend along the X direction and faces the four semiconductor laser portions 20 in the Y direction. The collimating lens 40 has four recesses 41, which collimate the laser light L from the four semiconductor laser portions 20. That is, the collimating lens 40 is configured as a collimating lens array in which four recesses 41 (parallelizing portions) corresponding to the four semiconductor laser portions 20 are arranged side by side along the X direction.

[0066] In the modification of FIG. 7, the bandpass filter 60 is placed on the light receiving section 51 (light receiving surface) of each light receiving sensor 50. In this example, the bandpass filter 60 is formed in a square shape. Alternatively, the bandpass filter 60 may be formed in a layer on the light receiving section 51 of each light receiving sensor 50. In this case, the bandpass filter 60 may be formed in a circular shape corresponding to the light receiving section 51, for example. In either case of being placed or being formed as a film, the bandpass filter 60 may be formed in any shape. In the modification of FIG. 7, the refractive index of the resin material R arranged between the collimator lens 40 and the semiconductor laser section 20 is equal to or higher than the refractive index of the active layer of the laser element 22 and equal to or lower than the refractive index of the collimator lens 40.

[0067] Even with this modification, each element can be suitably arranged, as in the above embodiment. Moreover, in this modification, one reflection block 30 reflects the laser light from the plurality of semiconductor laser units 20. In this case, since it is only necessary to provide one reflection block 30 corresponding to the plurality of semiconductor laser units 20, the reflection block 30 can be easily and accurately fixed to the wiring board 10. Moreover, it is possible to effectively prevent the heat generated in the semiconductor laser unit 20 from affecting the light receiving sensor 50, and it is also possible to effectively prevent the laser light L emitted from the semiconductor laser unit 20 to the opposite side of the collimator lens 40 from being detected as stray light by the light receiving sensor 50. Moreover, the reflection block 30 can also block light from the outside of the light emitting / receiving module 2 from entering the light receiving sensor 50.

[0068] In this modification, one collimator lens 40 collimates the laser light L from the multiple semiconductor laser portions 20. In this case, since it is only necessary to provide one collimator lens 40 corresponding to the multiple semiconductor laser portions 20, the collimator lens 40 can be easily and accurately fixed to the wiring board 10. In addition, the collimator lens 40 can effectively prevent the heat generated in the semiconductor laser portion 20 from affecting the light receiving sensor 50.

[0069] In the modification of FIG. 7, the semiconductor laser section 20 may have a chip-on-board structure, as in the above embodiment. In the modification of FIG. 7, four reflecting blocks 30 may be provided, as in the above embodiment. In the modification of FIG. 7, four collimating lenses 40 may be provided, as in the above embodiment. In the modification of FIG. 7, the bandpass filter 60 may be supported by a pair of supports 16 provided on the main surface 11 so as to sandwich the light receiving sensor 50, as in the above embodiment. That is, the combination of the configuration of the semiconductor laser section 20 (chip-on-board structure or laser chip structure), the configuration of the reflecting block 30 (one reflecting block 30 or multiple reflecting blocks 30), the configuration of the collimating lens 40 (one collimating lens 40 or multiple collimating lenses 40), and the configuration of the bandpass filter 60 (one bandpass filter 60, or multiple bandpass filters 60 placed or formed) is not limited to the above example, and may be any combination. In the modification of Fig. 7, one reflecting block 30 is provided corresponding to the four semiconductor laser portions 20, but two reflecting blocks 30 may be provided corresponding to the four semiconductor laser portions 20, for example. That is, each reflecting block 30 may correspond to two semiconductor laser portions 20. Similarly, in the modification of Fig. 7, one collimating lens 40 is provided corresponding to the four semiconductor laser portions 20, but two collimating lenses 40 may be provided corresponding to the four semiconductor laser portions 20, for example. That is, each collimating lens 40 may correspond to two semiconductor laser portions 20.

[0070] The present invention is not limited to the above-described embodiment and modified examples. For example, the materials and shapes of the components are not limited to those described above, and various materials and shapes can be adopted.

[0071] In the above embodiment, the reflection block 30 is located between the collimator lens 40 and the light receiving sensor 50, but the light receiving sensor 50 may be located on the opposite side of the semiconductor laser unit 20 to the collimator lens 40. That is, the corresponding light receiving sensor 50, the semiconductor laser unit 20, the collimator lens 40, and the reflection block 30 may be arranged in this order in the Y direction. The reflection block 30 may be a common member with the wiring board 10. For example, the reflection block 30 may be formed integrally with the wiring board 10 by integral molding. In this case, the reflection block 30 is formed of the same material as the wiring board 10.

[0072] The reflection block 30 may not have the flat surface 32. For example, the reflection block 30 may be formed in a triangular shape with the reflection surface 31 as the hypotenuse when viewed from the X direction without having the flat surface 32. In particular, when the reflection block 30 is formed integrally with the wiring board 10, the reflection block 30 does not need to be fixed to the wiring board 10 by die bonding, and the reflection block 30 does not need to be adsorbed by a pickup device, so the flat surface 32 may be omitted. In addition, as a method of picking up the reflection block 30, a method of pinching and lifting the reflection block 30 along the X direction is also considered. In this case, the flat surface 32 may also be omitted. The material of the reflection block 30 is not limited to silicon, and may be any material.

[0073] Only one semiconductor laser unit 20 may be provided. In this case, one each of the reflection block 30, collimator lens 40, and light receiving sensor 50 are also provided. The resin material R arranged between the collimator lens 40 and the semiconductor laser unit 20 may be omitted. The surface 40a of the collimator lens 40 does not need to have a recess 41 formed thereon. The bandpass filter 60 may be omitted. The light emitting and receiving module 2 may be applied to a distance measuring device other than a LiDAR device. The distance measuring device 1 may be a device that measures the distance to the target S by other methods such as a FMCW (Frequency Modulated Continuous Wave) method, not limited to the TOF method.

[0074] In the above embodiment, the electrodes 13 on the main surface 11 are electrically connected to the electrode pads 14 on the main surface 12 via through holes provided in the wiring board 10, but the electrodes 13 may be electrically connected to the electrode pads 14 via a side surface of the wiring board 10. In the above embodiment, the six electrodes 29 are grouped into three systems, the anode electrode 23, the cathode electrode 24, and the ground electrode 26, in the electrode pads 14 on the main surface 12, but they may be grouped into three systems in the electrodes 13 on the main surface 11, or may be grouped into three systems inside the wiring board 10. [Explanation of symbols]

[0075] 1...distance measuring device, 2...light emitting and receiving module (light emitting and receiving module for distance measuring), 3...control unit, 10...wiring board, 11...main surface, 16...support part, 20...semiconductor laser part, 21...submount board, 22...laser element (chip), 22a...end face (side), 30...reflection block, 31...reflection surface, 32...flat surface, 40...collimating lens, 40a...surface, 41...recess, 50...light receiving sensor, 60...bandpass filter, L...laser light, R...resin material, S...object.

Claims

1. A wiring substrate having a main surface; a semiconductor laser section provided on the main surface and configured to emit laser light from a side surface intersecting the main surface; a reflection block provided on the main surface, the reflection block having a reflection surface inclined with respect to the main surface and reflecting the laser light from the semiconductor laser portion to an opposite side to the wiring substrate; a collimator lens provided on the main surface and positioned between the semiconductor laser unit and the reflection block; A distance measuring light projecting and receiving module comprising: a light receiving sensor provided on the main surface for detecting the laser light emitted from the semiconductor laser portion, passing through the collimating lens, reflected by the reflecting surface of the reflecting block, and then reflected by an object.

2. 2. The distance measuring light emitting / receiving module according to claim 1, wherein the reflection block is located between the collimating lens and the light receiving sensor.

3. 3. The distance measuring light emitting and receiving module according to claim 1, wherein the reflection block is configured as a separate member from the wiring board and is fixed to the main surface.

4. 3. The distance measuring light emitting and receiving module according to claim 1, wherein the wiring board and the reflecting block are made of different materials.

5. 3. The distance measuring light emitting and receiving module according to claim 1, wherein the reflection block has a flat surface on a side opposite to the wiring board.

6. 3. The distance measuring light emitting and receiving module according to claim 1, wherein said reflective block is made of reflectively coated silicon.

7. 3. The distance measuring light emitting / receiving module according to claim 1, comprising a plurality of said semiconductor laser units.

8. A plurality of the reflection blocks are provided, 8. The distance measuring light emitting and receiving module according to claim 7, wherein the plurality of reflection blocks correspond one-to-one to the plurality of semiconductor laser units and reflect the laser light from the corresponding plurality of semiconductor laser units.

9. 8. The distance measuring light emitting and receiving module according to claim 7, wherein the reflection block reflects the laser light from the plurality of semiconductor laser portions.

10. A plurality of the collimating lenses are provided, 8. The distance measuring light emitting and receiving module according to claim 7, wherein the plurality of collimating lenses correspond one-to-one to the plurality of semiconductor laser sections, and collimate the laser light from the corresponding plurality of semiconductor laser sections.

11. 8. The distance measuring light emitting / receiving module according to claim 7, wherein the collimator lens collimates the laser light from the plurality of semiconductor laser units.

12. 3. The distance measuring light emitting / receiving module according to claim 1, further comprising a resin material disposed between said collimating lens and said semiconductor laser portion.

13. 3. The distance measuring light projecting and receiving module according to claim 1, wherein a recess recessed toward said semiconductor laser section is formed on a surface of said collimating lens opposite to said semiconductor laser section.

14. 3. The distance measurement light emitting / receiving module according to claim 1, wherein the semiconductor laser section has a submount substrate and a laser element mounted on the submount substrate, and is mounted on the main surface of the wiring substrate in the submount substrate.

15. a bandpass filter disposed on an opposite side of the wiring board with respect to the light receiving sensor; 3. The distance measuring light emitting and receiving module according to claim 1, wherein the bandpass filter is supported by a pair of supports provided on the main surface so as to sandwich the light receiving sensor therebetween.

16. 3. The distance measuring light emitting and receiving module according to claim 1, further comprising a layered bandpass filter formed on the light receiving portion of the light receiving sensor.

17. 3. The distance measuring light emitting and receiving module according to claim 1, further comprising a bandpass filter placed on the light receiving portion of the light receiving sensor.

18. A distance measuring light emitting / receiving module according to claim 1 or 2; A distance measuring device comprising: a control unit that calculates a distance to the object based on a detection result of the laser light by the light receiving sensor.

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