CN210089852U

CN210089852U - Optical power detection device of TOF (time of flight) light projection module

Info

Publication number: CN210089852U
Application number: CN201920666050.1U
Authority: CN
Inventors: 何立强; 肖晚辉
Original assignee: Shenzhen Ruiwai Technology Co Ltd
Current assignee: Shenzhen Ruiwai Technology Co Ltd
Priority date: 2019-05-05
Filing date: 2019-05-05
Publication date: 2020-02-18
Anticipated expiration: 2029-05-05

Abstract

The utility model discloses a luminous power detection device of a TOF light projection module, which shoots and identifies the brightest facula of the light projected by the TOF light projection module after imaging through a diffusion film through a camera; calculating a horizontal included angle theta b of the brightest light spot and an included angle theta a along the Z axis; adjusting the horizontal rotation angle of the optical power detector to be consistent with theta b through the central control rotation platform; after the included angle of the Z axis of the optical power detector is adjusted to be consistent with theta a through the angle rotating mechanism, the optical power of light projected by the TOF light projection module is detected, the safety range of human eyes can be accurately detected, and the problem of large detection error in the traditional method is effectively solved.

Description

Optical power detection device of TOF (time of flight) light projection module

Technical Field

The utility model relates to a TOF light throws the test field of module, especially relates to a device to the luminous power test of TOF light projection.

Background

The principle of the TOF technique is to use a transmitter to transmit light, such as laser light, infrared light, etc., to an object, receive a reflected light signal by a sensor, and calculate the distance between the object and the mobile phone according to the round-trip time of the light, so as to determine a reflection point. When the emitted laser light is sufficient, all the points can be connected into a solid surface. The existing products such as 3D face recognition cameras and the like mostly adopt TOF technology, infrared light, laser and the like need to be projected to faces in the recognition process, and for the safety of human eyes, the light power of light projected by a TOF light projection module needs to be detected to ensure that the light power is within the safety range of the human eyes.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a light power to TOF light projection module carries out accuracy, reasonable detection, ensures that the light that throws is in people's eye safety range.

The utility model provides a TOF light throws optical power detection device of module, its characterized in that: the device comprises an XY displacement module, a central control rotary platform connected with the XY displacement module, an angle rotary mechanism connected with the central control rotary platform, and an optical power detector arranged on the angle rotary mechanism; the device also comprises a diffusion film and a camera positioned on the diffusion film; the camera is used for shooting and identifying the brightest light spot of light projected by the TOF light projection module after the light is imaged by the diffusion film; the central control rotating platform can adjust the horizontal rotating angle of the optical power detector to be consistent with the horizontal included angle theta b of the brightest light spot; the angle rotating mechanism can adjust the included angle of the Z axis of the optical power detector to be consistent with the included angle theta a of the brightest light spot along the Z axis.

Further, the angle rotating mechanism comprises an angle mounting vertical plate, an angle adjusting motor fixedly mounted on a first side face of the angle mounting vertical plate, an arc guide rail arranged on a second side face, opposite to the first side face, of the angle mounting vertical plate, an angle sliding block and a rotating block, one end of the rotating block is connected with a rotor of the angle adjusting motor, the other end of the rotating block is movably connected with the arc guide rail through the angle sliding block, and the optical power detector is fixedly arranged on the rotating block.

Furthermore, the angle slider is provided with a guide wheel, the rotating block is provided with a linear guide groove extending from inside to outside, and the linear guide groove is matched with the guide wheel.

Further, angle rotary mechanism still includes L type piece, the vertical portion of L type piece is fixed to be set up in the side of rotatory piece keeping away from angle installation riser direction, and the optical power detector is installed in the horizontal portion of L type piece.

Furthermore, the XY displacement module comprises a module fixing plate, a Y-axis slide rail fixed on the bottom surface of the module fixing plate, a Y-axis slide block and a Y-axis servo motor for driving the Y-axis slide block to move along the Y-axis slide rail; the X-axis sliding block is fixedly arranged at the bottom of the Y-axis sliding block, the X-axis sliding rail is arranged on the bottom surface of the X-axis sliding block, the X-axis sliding block and the X-axis servo motor are used for driving the X-axis sliding block to move along the X-axis sliding rail.

Further, the X-axis sliding block hoisting device further comprises a hoisting frame, and the central control rotating platform is fixedly connected with the X-axis sliding block through the hoisting frame.

Furthermore, the camera is arranged on the angle mounting vertical plate and faces downwards along the Z axis on the second side face, and the diffusion film is fixedly arranged below the camera.

Drawings

Fig. 1 is a schematic diagram of the overall structure of the device in a preferred embodiment.

FIG. 2 is a schematic view of a camera of the device;

FIG. 3 is a schematic diagram of the device after a camera has shot and identified the brightest light spot;

fig. 4 is a schematic diagram of the horizontal angle of the brightest spot.

Detailed Description

The following will further describe certain preferred embodiments of the present invention with reference to the accompanying drawings and embodiments.

As shown in fig. 1, in a preferred embodiment, an optical power detection apparatus of a TOF light projection module includes an XY displacement module 1, a central control rotation platform 2, an optical power detector 4, and an angle rotation mechanism. The XY-displacement module 1 further comprises a module fixing plate 13, a Y-axis slide rail 112 fixed on the bottom surface of the module fixing plate 13, a Y-axis slider 113, and a Y-axis servo motor 111 for driving the Y-axis slider 113 to move along the Y-axis slide rail 112; the X-axis slide rail device comprises an X-axis cushion block 124 fixedly arranged at the bottom of a Y-axis slide block 113, an X-axis slide rail 122 arranged at the bottom of the X-axis cushion block 124, an X-axis slide block 123 and an X-axis servo motor 121 used for driving the X-axis slide block 123 to move along the X-axis slide rail 122. The central control rotary platform 2 is fixedly connected with the X-axis sliding block 123 through a hoisting frame 14, and the X, Y axis coordinate position of the whole central control rotary platform 2 can be adjusted under the driving of the Y-axis servo motor 111 and the X-axis servo motor 121. The central control rotary platform 2 has a rotary part capable of performing XY plane horizontal rotation by being driven by a motor inside the central control rotary platform 2.

The angle rotating mechanism comprises an angle mounting vertical plate 31, an angle adjusting motor 32 fixedly mounted on a first side surface of the angle mounting vertical plate 31, an arc guide rail 33 arranged on a second side surface of the angle mounting vertical plate 31 opposite to the first side surface, a rotating block 35 and an L-shaped block 352. The angle-mounting vertical plate 31 is connected with the rotating part of the central control rotating platform 2 through a transverse connecting plate 21. The rotating block 35 is arranged in parallel with the angle mounting vertical plate 31, a rotating shaft on a rotor of the angle adjusting motor 32 is fixedly connected with the rotating block 35, and the rotating block 35 can rotate under the action of the angle adjusting motor 32. The angle rotating mechanism further comprises an angle sliding block 34, and one end of the rotating block 35, which is far away from the angle adjusting motor 32, is connected with the arc guide rail 33 in a sliding manner through the angle sliding block 34. Preferably, the angle slider 34 is provided with a guide wheel 341, and the rotation block 35 is provided with a linear guide groove 351 extending from the inside to the outside. The longitudinal portion of the L-shaped block 352 is fixedly provided on the side surface of the rotating block 35 in the direction away from the angle mounting vertical plate 31, and the optical power detector 4 is mounted on the lateral portion of the L-shaped block 352. During work, the XY displacement module 1 is responsible for adjusting the position of the optical power detector 4 in the XY direction, and the central control rotary platform 2 is responsible for adjusting the angle of the optical power detector 4 on the horizontal plane; the angle rotating mechanism is responsible for adjusting angles between all directions and the Z axis. When the angle rotating mechanism works, the angle adjusting motor 32 controls the rotating block 35 to rotate by a required angle, and in the rotating process, the other end of the angle rotating mechanism is guided by the angle sliding block 34 and the arc guide rail 33, and the guide wheels 341 of the angle sliding block 34 and the guide grooves between the linear guide grooves 351 of the rotating block 35 are mutually limited and guided, so that the whole rotating process is smooth and stable, the error is small, and the shaking in the rotating process is prevented. In addition, the angle mounting vertical plate 31 is further provided with a camera 5 and a diffusion film 51 positioned below the camera 5 along the Z axis on the second side surface and on one side of the rotating block 35. The image formed by the light projected by the product after passing through the diffusion film 51 is photographed by the camera 5 and the diffusion film 51, and the placement position information of the product is judged by photographing.

Preferably, stoppers are provided at both ends of the circular arc guide 33 to prevent the angular slider 34 from being disengaged. Alternatively, the optical power meter 4 may be other sensing component of the optical power test.

With reference to fig. 2, 3 and 4, when the optical power detection device of the TOF light projection module performs a test, the camera 5 on the device is first moved to a position right above the TOF light projection module. The light of the TOF light projecting module is projected and imaged through the diffusion film 51. The camera 5 takes an image of the diffuser film 51 and then recognizes the brightest spot by software. The horizontal angle thetab of the brightest spot is then calculated, as well as the angle thetaa along the Z-axis. Moving an optical power detector 4 of an optical power detection device of the TOF optical projection module to be right above the TOF optical projection module through an XY displacement module; the horizontal rotation angle of the optical power detector 4 is adjusted through the central control rotary platform 2, so that the horizontal angle of the optical power detector 4 is the same as the horizontal included angle theta b of the brightest light spot; the included angle of the Z axis of the optical power detector 4 is adjusted through the angle rotating mechanism to enable the included angle theta a of the Z axis of the optical power detector 4 to be the same as the included angle theta a of the Z axis of the brightest light spot, and finally, after the optical power detector 4 is adjusted in place, the optical power of light projected by the TOF light projection module, such as infrared light, laser light and the like, can be detected, and whether the safety value of human eyes is exceeded or not is judged. Therefore, the maximum light power of the projected light can be accurately detected by finding out the maximum light spot projected, determining the angle of the maximum projected light distribution and then adjusting the detection angle of the optical power detector 4, so as to judge whether the maximum light power is in the safety range of human eyes, and effectively solve the problem of large error in the traditional detection.

Claims

1. An optical power detection device of a TOF light projection module, characterized in that: the device comprises an XY displacement module, a central control rotary platform connected with the XY displacement module, an angle rotary mechanism connected with the central control rotary platform, and an optical power detector arranged on the angle rotary mechanism; the device also comprises a diffusion film and a camera positioned on the diffusion film; the camera is used for shooting and identifying the brightest light spot of light projected by the TOF light projection module after the light is imaged by the diffusion film; the central control rotating platform can adjust the horizontal rotating angle of the optical power detector to be consistent with the horizontal included angle theta b of the brightest light spot; the angle rotating mechanism can adjust the included angle of the Z axis of the optical power detector to be consistent with the included angle theta a of the brightest light spot along the Z axis.

2. The optical power detection device of the TOF light projection module according to claim 1, wherein the angle rotation mechanism comprises an angle mounting vertical plate, an angle adjusting motor fixedly mounted on a first side surface of the angle mounting vertical plate, an arc guide rail disposed on a second side surface of the angle mounting vertical plate opposite to the first side surface, an angle slider, and a rotation block, one end of the rotation block is connected to a rotor of the angle adjusting motor, the other end of the rotation block is movably connected to the arc guide rail through the angle slider, and the optical power detector is fixedly disposed on the rotation block.

3. The apparatus of claim 2, wherein the angle slider is provided with a guide wheel, and the rotation block is provided with a linear guide groove extending from inside to outside, and the linear guide groove is adapted to the guide wheel.

4. The apparatus of claim 3, wherein the angle rotation mechanism further comprises an L-shaped block, a longitudinal portion of the L-shaped block is fixedly disposed on a side of the rotation block away from the direction of the vertical angle-mounting plate, and the optical power detector is mounted on a transverse portion of the L-shaped block.

5. The apparatus of claim 4, wherein the XY-shift module comprises a module fixing plate, a Y-axis slide rail fixed on a bottom surface of the module fixing plate, a Y-axis slider, and a Y-axis servo motor for driving the Y-axis slider to move along the Y-axis slide rail; the X-axis sliding block is fixedly arranged at the bottom of the Y-axis sliding block, the X-axis sliding rail is arranged on the bottom surface of the X-axis sliding block, the X-axis sliding block and the X-axis servo motor are used for driving the X-axis sliding block to move along the X-axis sliding rail.

6. The optical power detection device of the TOF light projection module of claim 5, further comprising a hoisting frame, wherein the central control rotating platform is fixedly connected with the X-axis slider through the hoisting frame.

7. The apparatus of claim 6, wherein said camera is disposed on said angle mounting plate and faces downward along the Z-axis on said second side, and said diffusing film is fixed under said camera.