Packaging structure of time-of-flight distance sensor
By using a conductive part to monitor the displacement of the diffuser in the packaging structure of the time-of-flight distance sensor, the problems of complex packaging structure and difficulty in monitoring the displacement of the diffuser in the existing technology are solved, achieving higher safety in use and lower cost. production costs.
Patent Information
- Application Number
- CN202411787228.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-01-21
AI Technical Summary
The package construction of the existing time-of-flight distance sensor is complex, and the reference detector and measurement detector are not strictly separated, resulting in interference in measurement results, and the mechanism for monitoring diffusion plate displacement is complex, which increases cost and difficulty.
Design a packaging structure of a flight time distance sensor. By setting the conductive department on the diffuser, the electrical connection with the conductive line of the substrate to determine whether the diffuser is displaced or shed through the impedance of the electrical department, thereby turning off the light transmission unit To avoid directly projected on the eyes of the light source.
The packaging structure of the time-of-flight distance sensor is simplified, the safety of use is improved, the production cost and complexity are reduced, and the damage to the human eyes by the light source is avoided.
Smart Images
Figure CN119335546A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a packaging structure of a time-of-flight distance sensor, and in particular to a packaging structure of a time-of-flight distance sensor that can be used to detect whether a diffusion sheet is displaced. Background Art
[0002] The principle of time of flight (ToF) is to use a light emitting diode (LED) to emit infrared light and illuminate the surface of an object. The sensor then receives the light reflected by the object. The sensor calculates the time difference or phase difference between the emission and reflection of the light to convert the distance of the object to generate depth information. In addition, it can be further combined with traditional camera shooting to present the three-dimensional outline of the object in the form of a topographic map with different colors representing different distances.
[0003] The packaging structure of the existing time-of-flight distance sensor is relatively complex, and the reference detector and the measurement detector are usually not strictly separated, so that the measurement detector can receive the light emitted by the laser, thereby causing certain interference to the measurement result. In addition, the mechanism for monitoring whether the diffusion plate of the packaging structure of the time-of-flight distance sensor is displaced is too complicated, which is not conducive to reducing the cost and complexity of production. Therefore, it is urgent to design a packaging structure of the time-of-flight distance sensor to solve the above problems. Summary of the invention
[0004] In order to solve the above-mentioned problems of the prior art, the present invention proposes a packaging structure of a time-of-flight distance sensor, which mainly includes a diffusion sheet disposed on a light emitting unit and a conductive part disposed on the diffusion sheet. By measuring the impedance change of the conductive part, it can be determined whether the diffusion sheet is displaced or detached relative to the light emitting unit, thereby improving the safety of the packaging structure of the time-of-flight distance sensor in use.
[0005] One object of the present invention is to provide a packaging structure of a time-of-flight distance sensor, which mainly includes a substrate, a cover, a light emitting unit, a light sensing unit and a diffusion sheet. The light emitting unit and the light sensing unit are arranged on the substrate, and the cover is connected to the substrate, so that the light emitting unit and the light sensing unit are respectively located in a first accommodation space and a second accommodation space between the cover and the substrate. The diffusion sheet is arranged on the optical path of the light source of the light emitting unit, so that the light source generated by the light emitting unit is projected to the outside through the diffusion sheet.
[0006] A conductive part is disposed on the surface or inside of the diffuser, wherein the conductive part is electrically connected to the conductive circuit on the substrate, and the impedance of the conductive part can be measured through the conductive circuit on the substrate. When the measured impedance of the conductive part changes, it indicates that the diffuser may be displaced or detached relative to the light emitting unit, and the light emitting unit may be further turned off to prevent the light source generated by the light emitting unit from being directly projected onto the human eye.
[0007] In order to achieve the above-mentioned purpose, the present invention proposes a packaging structure of a time-of-flight distance sensor, characterized in that it includes: a substrate including at least one conductive circuit; a light emitting unit disposed on the substrate; a light sensing unit disposed on the substrate; a cover body, the cover body is connected to the substrate, and a first accommodating space and a second accommodating space are formed between the cover body and the substrate, the light emitting unit and the light sensing unit are respectively located in the first accommodating space and the second accommodating space, wherein the cover plate includes a first through hole and a second through hole, the first through hole is connected to the first accommodating space, and the second through hole is connected to the second accommodating space; a diffusion sheet is located between the light emitting unit and the first through hole, wherein a light source generated by the light emitting unit will pass through the diffusion sheet and project to the outside; and a conductive part is disposed on the diffusion sheet, wherein the conductive circuit of the substrate is connected to the conductive part, and the impedance of the conductive part is measured through the conductive circuit to determine whether the diffusion sheet is displaced relative to the light emitting unit.
[0008] In at least one embodiment of the package structure of the time-of-flight distance sensor, a first filter unit is disposed in the first through hole, and the light source generated by the light emitting unit is sequentially projected onto at least one object through the diffuser and the first filter unit.
[0009] In at least one embodiment of the package structure of the time-of-flight distance sensor, a second filter unit is disposed in the second through hole, and the light sensing unit receives the reflected or scattered light source of the object through the second filter unit.
[0010] In at least one embodiment of the packaging structure of the time-of-flight distance sensor, the cover is made of a light-proof material to block the light source generated by the light emitting unit.
[0011] In at least one embodiment of the packaging structure of the time-of-flight distance sensor, a retaining wall is provided between the first accommodating space and the second accommodating space of the cover, and the retaining wall is located between the light emitting unit and the light sensing unit.
[0012] In at least one embodiment of the package structure of the time-of-flight distance sensor, at least one conductive wire is included to connect the conductive portion of the diffusion sheet and the conductive circuit on the substrate.
[0013] In at least one embodiment of the package structure of the time-of-flight distance sensor, at least one conductive sheet is connected to the conductive portion of the diffusion sheet and the conductive circuit on the substrate.
[0014] In at least one embodiment of the package structure of the time-of-flight distance sensor, a support portion is disposed near the light emitting unit, and a diffusion sheet is disposed on the support portion.
[0015] The present invention proposes a packaging structure of a time-of-flight distance sensor, which can monitor whether a diffusion sheet is displaced relative to a light emitting unit through a simple circuit connection, thereby improving the safety of the packaging structure of the time-of-flight distance sensor without increasing the cost and difficulty of product manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a cross-sectional schematic diagram of an embodiment of the packaging structure of a time-of-flight distance sensor of the present invention.
[0017] Figure 2 It is a three-dimensional schematic diagram of an embodiment of a diffusion sheet and a conductive part of a packaging structure of a time-of-flight distance sensor of the present invention.
[0018] Explanation of the reference numerals: 10 - packaging structure of the time-of-flight distance sensor; 11 - substrate; 111 - conductive circuit; 13 - cover; 131 - first accommodating space; 132 - retaining wall; 133 - second accommodating space; 135 - first perforation; 137 - second perforation; 151 - light emitting unit; 153 - light sensing unit; 155 - supporting portion; 171 - diffuser; 173 - conductive portion; 175 - conductive line; 191 - first filter unit; 193 - second filter unit. DETAILED DESCRIPTION
[0019] See also Figure 1 , is a cross-sectional schematic diagram of an embodiment of the package structure of the time-of-flight distance sensor of the present invention. As shown in the figure, the package structure 10 of the time-of-flight distance sensor includes a substrate 11, a cover 13, a light emitting unit 151, a light sensing unit 153 and a diffusion sheet 171, wherein the substrate 11 is connected to the cover 13, and the light emitting unit 151 and the light sensing unit 153 are packaged between the substrate 11 and the cover 13.
[0020] In actual application, the light emitting unit 151 and the light sensing unit 153 may be disposed on the substrate 11 first, and the electrical connection between the light emitting unit 151 and the light sensing unit 153 and the substrate 11 may be completed. For example, a plurality of conductive circuits 111 may be disposed on the surface or inside of the substrate 11, wherein the light emitting unit 151 and the light sensing unit 153 are connected to part of the conductive circuits 111 of the substrate 11. The substrate 11 may provide driving power to the light emitting unit 151 and the light sensing unit 153 via the conductive circuits 111, and transmit signals with the light emitting unit 151 and / or the light sensing unit 153. For example, the light emitting unit 151 may be a light emitting diode or a laser diode, and the light sensing unit 153 may be a CMOS sensor.
[0021] In one embodiment of the present invention, the light emitting unit 151 and the light sensing unit 153 may be fixed on the surface of the substrate 11 by a colloid. For example, the light emitting unit 151 may be a surface mounted LED (SMD: Surface Mount Device) or a VCSEL.
[0022] The cover 13 is made of opaque material and can be used to block the light generated by the light emitting unit 151. The cover 13 includes a first accommodation space 131 and a second accommodation space 133. When the cover 13 is connected to the substrate 11, the first accommodation space 131 and the second accommodation space 133 are aligned with the light emitting unit 151 and the light sensing unit 153 respectively.
[0023] After the cover 13 is connected to the substrate 11, the first accommodating space 131 and the second accommodating space 133 are located between the cover 13 and the substrate 11, and the light emitting unit 151 and the light sensing unit 153 are respectively located in the first accommodating space 131 and the second accommodating space 133. Specifically, a retaining wall 132 is provided between the first accommodating space 131 and the second accommodating space 133 of the cover 13, wherein the retaining wall 132 is located between the light emitting unit 151 and the light sensing unit 153 to prevent the light sensing unit 153 from directly receiving the light source generated by the light emitting unit 151, thereby affecting the accuracy of the distance measured by the package structure 10 of the time-of-flight distance sensor.
[0024] The cover 13 further includes a first through hole 135 and a second through hole 137 , wherein the first through hole 135 is connected to the first accommodating space 131 , and the second through hole 137 is connected to the second accommodating space 133 .
[0025] The light source generated by the light emitting unit 151 in the first accommodating space 131 is projected onto an object outside the packaging structure 10 of the time-of-flight distance sensor through the first through-hole 135 of the cover body 13, while the light sensing unit 153 in the second accommodating space 133 receives the light source reflected and / or scattered by the object through the second through-hole 137 of the cover body 13.
[0026] The diffuser 171 is disposed between the light emitting unit 151 and the first through hole 135, and is located on the optical path of the light source generated by the light emitting unit 151, so that the light source generated by the light emitting unit 151 is projected onto an object outside the package structure 10 of the time-of-flight distance sensor through the diffuser 171. The diffuser 171 is mainly used to diffuse the light source generated by the light emitting unit 151 to increase the field of view of the light source generated by the light emitting unit 151, and at the same time, it can prevent the overly concentrated light source from being directly projected onto the human eye to improve the safety of use.
[0027] In one embodiment of the present invention, a first filter unit 191 may be disposed on the first through hole 135, wherein the light generated by the light emitting unit 151 is sequentially projected onto an object outside the package structure 10 of the time-of-flight distance sensor through the diffuser 171 and the first filter unit 191. A second filter unit 193 may be disposed on the second through hole 137, so that the light sensing unit 153 receives the reflected or scattered light from the object through the second filter unit 193, wherein the second filter unit 193 may filter out light other than the light generated by the light emitting unit 151.
[0028] Generally speaking, the diffuser 171 can be mounted on the light emitting unit 151, wherein the light source generated by the light emitting unit 151 can pass through the diffuser 171. In one embodiment of the present invention, at least one supporting portion 155 can be disposed on the substrate 11, wherein the supporting portion 155 is located near the light emitting unit 151, and the diffuser 171 can be disposed on the supporting portion 155 through a colloid. For example, two supporting portions 155 can be disposed on both sides of the light emitting unit 151, and the diffuser 171 can be disposed on the supporting portion 155.
[0029] During the use of the package structure 10 of the time-of-flight distance sensor, if the diffusion sheet 171 is displaced or falls off relative to the light emitting unit 151, the distance measurement performance of the package structure 10 of the time-of-flight distance sensor may be affected. In addition, if the light source generated by the light emitting unit 151 is directly projected onto the human eye, it may cause damage to the human eye.
[0030] To this end, the present invention proposes to set a conductive portion 173 on the diffuser 171. For example, the conductive portion 173 can be a metal circuit with a special shape set on the upper surface or side surface of the diffuser, such as Figure 2 shown. Figure 2 The shape of the conductive part 173 is only an embodiment of the present invention and is not intended to limit the scope of the present invention. In practical applications, the shape, location or wire diameter of the conductive part 173 may be changed according to requirements.
[0031] The conductive portion 173 on the diffuser 171 is electrically connected to the conductive circuit 111 of the substrate 11, and the impedance of the conductive portion 173 on the diffuser 171 can be measured through the conductive circuit 111 on the substrate 11. For example, the conductive portion 173 on the diffuser 171 can be connected to the conductive circuit 111 of the substrate 11 via the conductive line 175. By measuring the impedance change of the conductive portion 173 through the conductive circuit 111, it is determined whether the diffuser 171 disposed on the light emitting unit 151 is displaced or detached.
[0032] In one embodiment of the present invention, the conductive portion 173 on the diffuser 171 can be connected to a processor through the conductive line 111 on the substrate 11, and the processor measures and determines the impedance change of the conductive portion 173. For example, when the processor measures that the change in the impedance value of the conductive portion 173 exceeds a default value, it can be determined that the diffuser 171 is displaced or detached relative to the light emitting unit 151, and the driving power provided to the light emitting unit 151 can be further turned off to prevent the light source generated by the light emitting unit 151 from being directly projected onto the human eye without passing through the diffuser 171, so as to improve the use safety of the package structure 10 of the time-of-flight distance sensor.
[0033] Generally speaking, the package structure 10 of the time-of-flight distance sensor is very small. If an additional sensor is provided inside the package structure 10 of the time-of-flight distance sensor, and the sensor is used to detect whether the diffuser 171 is displaced or detached relative to the light emitting unit 151, the manufacturing difficulty and cost of the package structure 10 of the time-of-flight distance sensor will be increased. In contrast, the package structure 10 of the time-of-flight distance sensor of the present invention only needs to provide a conductive portion 173 on the diffuser 171, and then connect the conductive portion 173 and the conductive line 111 of the substrate 11, so as to detect whether the diffuser 171 is displaced or detached relative to the light emitting unit 151, without the need to provide an additional sensor in the first accommodating space 131, so as to improve the safety of use without increasing the manufacturing difficulty and cost of the package structure 10 of the time-of-flight distance sensor.
[0034] Advantages of the present invention:
[0035] A conductive part is disposed on the surface or inside of the diffuser, wherein the conductive part is electrically connected to the conductive circuit on the substrate, and the impedance of the conductive part can be measured through the conductive circuit on the substrate. By measuring the impedance of the conductive part, the purpose of monitoring whether the diffuser is displaced relative to the light emitting unit can be achieved, which is beneficial to improving the safety of the packaging structure of the time-of-flight distance sensor without increasing the cost and difficulty of product production.
[0036] The above is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. That is, all equivalent changes and modifications to the shape, structure, characteristics and spirit described in the patent application scope of the present invention should be included in the patent application scope of the present invention.
Claims
1. A packaging structure of a time-of-flight distance sensor, characterized in that: include: A substrate including at least one conductive circuit; a light emitting unit, disposed on the substrate; A light sensing unit is disposed on the substrate; a cover body, the cover body is connected to the substrate, and a first accommodating space and a second accommodating space are formed between the cover body and the substrate, the light emitting unit and the light sensing unit are respectively located in the first accommodating space and the second accommodating space, wherein the cover plate includes a first through hole and a second through hole, the first through hole is connected to the first accommodating space, and the second through hole is connected to the second accommodating space; a diffusion sheet located between the light emitting unit and the first through hole, wherein a light source generated by the light emitting unit passes through the diffusion sheet and is projected to the outside; and A conductive part is arranged on the diffusion sheet, wherein the conductive circuit of the substrate is connected to the conductive part, and the resistance change of the conductive part is monitored through the conductive circuit to determine whether the diffusion sheet is displaced relative to the light emitting unit.
2. The packaging structure of the time-of-flight distance sensor according to claim 1, characterized in that: A first filter unit is disposed on the first through hole. The light source generated by the light emitting unit is sequentially projected onto at least one object through the diffusion sheet and the first filter unit.
3. The packaging structure of the time-of-flight distance sensor according to claim 2, characterized in that: A second filter unit is disposed on the second through hole, and the light sensing unit receives the light source reflected or scattered by the object through the second filter unit.
4. The packaging structure of the time-of-flight distance sensor according to claim 3, characterized in that: The cover is made of opaque material to block the light source generated by the light emitting unit.
5. The packaging structure of the time-of-flight distance sensor according to claim 4, characterized in that: A blocking wall is provided between the first accommodating space and the second accommodating space of the cover body, and the blocking wall is located between the light emitting unit and the light sensing unit.
6. The packaging structure of the time-of-flight distance sensor according to claim 1, characterized in that: At least one conductive line is included to connect the conductive part of the diffusion sheet and the conductive circuit on the substrate.
7. The packaging structure of the time-of-flight distance sensor according to claim 1, characterized in that: It includes at least one conductive sheet connected to the conductive part of the diffusion sheet and the conductive circuit on the substrate.
8. The packaging structure of the time-of-flight distance sensor according to claim 1, characterized in that: A supporting part is arranged near the light emitting unit, and the diffusion sheet is arranged on the supporting part.