CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 202220757763.0, filed April 1, 2022, entitled “A LIDAR PATCH PLANAR MIRROR,” the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to the field of lidars, and in particular relates to a patch plane reflection mirror for a lidar.

BACKGROUND

At present, plane reflection mirrors for vehicle-mounted lidar are usually made of a single material, such as plastic, metal and glass. However, the surface profile of the plastic material is difficult to control when it moves and is heated, and the metal material and the glass material result in high costs. Furthermore, when the plane reflection mirror is made of a glass material, the assembly methods are relatively limited, and the assembly stability is also insufficient.

SUMMARY

In view of the shortcomings in the prior art, an objective of the present invention is to provide a patch plane reflection mirror for a lidar, in which a substrate with relatively low surface profile accuracy and a thin optical reflection lens with high surface profile accuracy and good surface quality are used, and the substrate and the thin optical reflection lens are fixed by adhesive bonding, which allows good optical surface profile of the plane reflection mirror and could solve the problem of high production cost of the plane reflection mirror with a single material as well as improve the convenience and stability of assembly.

In order to achieve the above objective, the present invention provides the following technical solutions.

A patch plane reflection mirror for a lidar comprises a substrate and a thin optical reflection lens, wherein the substrate and the thin optical reflection lens are fixed by adhesive bonding.

Further, the bonding surface of the substrate is provided with adhesive grooves. Further, the adhesive grooves include side adhesive grooves and middle adhesive grooves, wherein the side adhesive grooves are provided at the edges of the bonding surface of the substrate.

Further, the number of the side adhesive grooves is two, and the two side adhesive grooves are provided at two opposite edges of the bonding surface.

Further, the side adhesive grooves comprise chamfer grooves.

Further, the middle adhesive grooves comprise closed-loop adhesive grooves which have centrosymmetric structures.

Further, the middle adhesive grooves comprise a plurality of closed-loop adhesive grooves which are arranged in sequence from inside to outside.

Further, the middle adhesive grooves comprise dot adhesive grooves located in the middle of the closed-loop adhesive grooves.

Further, a plurality of middle adhesive grooves is arranged in a centrosymmetric manner.

Further, the closed-loop adhesive grooves include rectangular-loop adhesive grooves or circular-loop adhesive grooves.

Further, the side walls of the substrate are symmetrically provided with protrusions, and the side adhesive grooves extend to the edges of the bonding surfaces of the protrusions.

Further, the inner walls of the adhesive grooves are provided with auxiliary bonding layers for improving the bonding.

Further, the front surface of the substrate is connected to the thin optical reflection lens, and the back surface of the substrate is provided with weight reduction grooves.

Further, the substrate is provided with an auxiliary installation structure formed integrally.

Further, a first adhesive is provided in the middle adhesive grooves, and a second adhesive is provided in the side adhesive grooves, and the shore hardness of the first adhesive is different from that of the second adhesive.

In summary, the present invention has the following beneficial effects.

1. A substrate with relatively low surface profile accuracy and a thin optical reflection lens with high surface profile accuracy and good surface quality are used, and the substrate and the thin optical reflection lens are fixed by adhesive bonding, which allows good optical surface profile of the plane reflection mirror and could solve the problem of high production cost of the plane reflection mirror with a single material. 2. The side adhesive grooves and the middle adhesive grooves together provide a multi-point bonding of the thin optical reflection lens. Compared with the entire surface bonding, the multi-point bonding is beneficial to meet the requirements of high surface profile accuracy and high stability of the thin optical reflection lens and could ensure the firmness and stability of the bonding.

3. The rectangular-loop adhesive grooves or the circular-loop adhesive grooves could improve the uniformity of the stress change at the bonding locations, which is beneficial to meet the requirements of high surface profile accuracy and high stability of the thin optical reflection lens and ensures the firmness and stability of the bonding.

4. The protrusions facilitate to increase the structural strength of the substrate and the firmness and stability of the bonding.

5. The substrate is provided with an auxiliary installation structure formed integrally, which facilitates the installation of the product.

6. The back surface of the substrate is provided with weight reduction grooves, which could reduce the weight of the product.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a patch plane reflection mirror for a lidar according to embodiment 1.

FIG. 2 is a schematic structural diagram of a substrate according to embodiment 1.

FIG. 3 is a schematic structural diagram of a patch plane reflection mirror for a lidar according to embodiment 2.

FIG. 4 is a schematic structural diagram of a patch plane reflection mirror for a lidar according to embodiment 3.

FIG. 5 is a schematic structural diagram of a substrate according to embodiment 3.

FIG. 6 is a schematic structural diagram of a substrate according to embodiment 4.

FIG. 7 is a schematic structural diagram of a substrate according to embodiment 5.

FIG. 8 is a schematic structural diagram of a substrate according to embodiment 6.

Reference numerals: 1, thin optical reflection lens; 2, substrate; 21, middle adhesive groove; 22, side adhesive groove; 23, protrusion; 24, weight reduction groove; 25, auxiliary installation structure. DETAILED DESCRIPTION OF EMBODIMENTS

The present invention will be further described in detail below with reference to the accompanying drawings.

These specific embodiments are merely intended to explain the present invention instead of limiting the present invention. After reading the specification, those skilled in the art could make modifications to the present embodiments as required without creative contributions, and all these modifications fall within the scope of the claims of the present invention.

Embodiment 1:

Referring to FIG. 1 , a patch plane reflection mirror for a lidar comprises a substrate 2 and a thin optical reflection lens 1, wherein the substrate 2 and the thin optical reflection lens 1 are fixed by adhesive bonding. In this embodiment, the substrate 2 with relatively low surface profile accuracy and the thin optical reflection lens 1 with high surface profile accuracy and good surface quality are used, and the substrate and the thin optical reflection lens are fixed by adhesive bonding, which allows good optical surface profile of the plane reflection mirror and could solve the problem of high production cost of the plane reflection mirror with a single material.

Referring to FIG. 1, in this embodiment, the thin optical reflection lens 1 could be processed from a silicon wafer, a standard wafer, a thin glass sheet, a thin metal sheet, etc., to achieve high surface profile accuracy and good surface quality. The optical surface could be treated depending on the waveband used to meet the requirement of specific reflection. The substrate 2 could be made of a material with low cost and easy to process, such as ceramic and metal, etc.

Referring to FIG. 1, preferably, adhesive grooves are provided on the bonding surface of the substrate 2. With the adhesive grooves, the firmness and stability of the bonding could be improved, and it is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1. Preferably, the inner walls of the adhesive grooves are provided with auxiliary bonding layers for improving the bonding. Specifically, surface treatment is performed on the inner wall of the adhesive groove to form the auxiliary bonding layer. The surface treatment includes surface cleanliness treatment, surface roughness treatment, or surface chemical treatment. The surface treatment could be selected depending on the materials of the substrate 2 and the thin optical reflection lens 1 and is not limited herein.

Referring to FIG. 1, preferably, the adhesive grooves comprise side adhesive grooves 22 and middle adhesive grooves 21 , wherein the side adhesive grooves 22 are provided at the edges of the bonding surface of the substrate 2. The side adhesive grooves 22 and the middle adhesive grooves 21 together provide a multi-point bonding of the thin optical reflection lens 1. Compared with the entire surface bonding, the multi-point bonding is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1 and could ensure the firmness and stability of the bonding. Preferably, the number of the side adhesive grooves 22 is two, and the two side adhesive grooves 22 are provided at two opposite edges of the bonding surface. The two side adhesive grooves 22 are arranged symmetrically, and the side adhesive grooves 22 are not formed as a closed loop, which is also beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1. Specifically, in this embodiment, both the thin optical reflection lens 1 and the substrate 2 are rectangular, and the side adhesive grooves 22 are provided at the long sides of the substrate 2 to ensure the firmness and stability of the bonding. Preferably, in this embodiment, the side adhesive grooves 22 are chamfer grooves, that is, chamfers are provided at the edges of the substrate 2 to form chamfer grooves. The chamfer grooves provide the advantages of simple structure, high structural strength, convenient processing, etc. In other embodiments, the side adhesive grooves 22 may be sunken grooves, which is not limited herein.

Referring to FIG. 1 , in this embodiment, the middle adhesive grooves 21 comprise closed- loop adhesive grooves which have centrosymmetric structures. The closed-loop adhesive grooves with centrosymmetric structures improve the uniformity of the stress change at the bonding locations, which is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1 and ensures the firmness and stability of the bonding. In this embodiment, the centrosymmetric structure of the closed-loop adhesive groove means that the closed-loop adhesive groove has a centrosymmetric plane, and the portions of the closed-loop adhesive groove located on both sides of the centrosymmetric plane are symmetrical. In this embodiment, the closed-loop adhesive groove is a rectangular-loop adhesive groove which has two centrosymmetric planes perpendicular to each other, and the two centrosymmetric planes perpendicular to each other are also the centrosymmetric planes of the rectangular substrate so that the uniformity of the stress change at the bonding locations could be improved, which is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1 and ensures the firmness and stability of the bonding. In other embodiments, the formation of the closed-loop adhesive groove could be adjusted as required, which is not limited herein. Preferably, the closed-loop adhesive groove has a centrosymmetric structure.

Referring to FIG. 1, preferably, the middle adhesive grooves 21 comprise a plurality of closed-loop adhesive grooves which are arranged in sequence from inside to outside to increase the firmness and stability of the bonding and meet the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1. Specifically, in this embodiment, the middle adhesive grooves 21 comprise two rectangular-loop adhesive grooves arranged from inside to outside. In other optional embodiments, the number of the closed-loop adhesive grooves could be adjusted as required or depending on the size of the substrate 2, which is not limited herein.

Referring to FIGS. 1 and 2, preferably, in this embodiment, the side walls of the substrate 2 are symmetrically provided with protrusions 23, and the side adhesive grooves 22 extend to the edges of the bonding surfaces of the protrusions 23. The protrusions 23 facilitate to increase the structural strength of the substrate 2 and the firmness and stability of the bonding. In this embodiment, each of the two opposite long sides of the substrate 2 is provided with a protrusion 23 so that the substrate 2 is generally in the form of a shuttle. In other optional embodiments, the configuration of the overall structure of the substrate 2 could be adjusted depending on the needs of the structural strength and bonding, which is not limited herein. In this embodiment, the front surface of the substrate 2 is connected to the thin optical reflection lens 1. Preferably, the back surface of the substrate 2 is provided with a weight reduction groove 24. The weight reduction groove 24 could reduce the weight of the product. In this embodiment, the back surface of the substrate 2 is provided with a circular weight reduction groove 24. In other optional embodiments, the number and shape of the weight reduction groove 24 could be adjusted as required, which is not limited herein.

Referring to FIG. 1 , in this embodiment, a first adhesive is provided in the middle adhesive grooves 21, a second adhesive is provided in the side adhesive grooves 22, and the shore hardness of the first adhesive is different from that of the second adhesive so that the uniformity of the stress change at the bonding locations could be increased, which is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens 1 and ensures the firmness and stability of the bonding. Specifically, in this embodiment, both the first adhesive and the second adhesive are glue, and the glue with higher shore hardness is used in the middle adhesive grooves 21, and the glue with lower shore hardness is used in the side adhesive grooves 22. In other optional embodiments, the glue at different locations could be adjusted depending on the material of the substrate 2 or the thin optical reflection lens 1 , which is not limited herein. For example, the glue with lower shore hardness is selected for the middle adhesive grooves 21 , and the glue with higher shore hardness is selected for the side adhesive grooves 22. Alternatively, the glue in the middle adhesive grooves 21 and the glue in the side adhesive grooves 22 have the same shore hardness.

Embodiment 2:

FIG. 3 shows a patch plane reflection mirror for a lidar. Referring to FIG. 3, the difference between the present embodiment and embodiment 1 lies in that, in the present embodiment, the middle adhesive grooves 21 comprise circular-loop adhesive grooves, and the substrate 2 is provided with three middle adhesive grooves 21. The circular-loop adhesive grooves with centrosymmetric structures further increase the uniformity of the stress change at the bonding locations, which is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens. Preferably, in this embodiment, the three middle adhesive grooves 21 are arranged in a centrosymmetric manner. Specifically, each of the three middle adhesive grooves 21 has two centrosymmetric planes perpendicular to each other, and the two centrosymmetric planes perpendicular to each other are also the centrosymmetric planes of the rectangular substrate so that the uniformity of the stress change at the bonding locations could be increased, which is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens and ensures the firmness and stability of the bonding. In other optional embodiments, the number of the middle adhesive grooves 21 could be adjusted as required, which is not limited herein.

Referring to FIG. 3, preferably, in this embodiment, the middle adhesive grooves 21 further comprise dot adhesive grooves located in the middle of the closed-loop adhesive grooves. In this embodiment, the dot adhesive grooves are circular and corporate with the circular-loop adhesive grooves so that the middle adhesive grooves 21 are in the form of a circular target, which facilitates to improve the uniformity of the stress change at the bonding locations and is beneficial to meeting the requirements of high surface profile accuracy and high stability of the thin optical reflection lens and ensures the firmness and stability of the bonding. Specifically, for the three middle adhesive grooves 21 in this embodiment, the middle adhesive groove 21 located in the middle comprises a dot adhesive groove and two circular-loop adhesive grooves arranged along the radial direction, and each of the middle adhesive grooves on the side comprises a dot adhesive groove and one circular-loop adhesive groove. That is, the number of the circular-loop adhesive grooves of the middle adhesive grooves 21 could be adjusted depending on the width of the substrate 2 at the corresponding position, which is not limited herein. In other optional embodiments, a plurality of middle adhesive grooves 21 with different shapes may be provided in the substrate 2, which is not limited herein. For example, rectangular-loop adhesive grooves and circular-loop adhesive grooves could be used together.

Embodiment 3:

Referring to FIGS. 4 and 5, the difference between the present embodiment and embodiment 2 lies in that, in this embodiment, the three protrusions 23 spaced from each another are respectively provided on two long sides of the substrate 2 so that the substrate 2 is generally in the form of a fishbone. In this embodiment, the weight reduction groove 24 on the back surface of the substrate 2 is a waist type groove, and the weight reduction groove 24 in the waist type could extend in the longitudinal direction of the substrate 2 and, compared with the circular weight reduction groove 24, further reduce the weight of the product.

Embodiment 4:

Referring to FIG. 6, the difference between the present embodiment and embodiment 1 lies in that, in this embodiment, the substrate 2 is provided with an auxiliary installation structure 25 formed integrally to facilitate the installation of the product. Specifically, in this embodiment, the auxiliary installation structure 25 comprises engaging positioning slots symmetrically arranged at the two ends of the substrate 2 in the longitudinal direction of the substrate. In other optional embodiments, the auxiliary installation structure 25 could be adjusted as required, which is not limited herein.

Embodiment 5:

Referring to FIG. 7 the difference between the present embodiment and embodiment 2 lies in that, in this embodiment, the substrate 2 is provided with an auxiliary installation structure 25 formed integrally to facilitate the installation of the product. Specifically, in this embodiment, the auxiliary installation structure 25 comprises fasteners symmetrically provided at the two ends of the substrate 2 in the longitudinal direction of the substrate. In other optional embodiments, the auxiliary installation structure 25 could be adjusted as required, which is not limited herein. Embodiment 6:

Referring to FIG. 8, the difference between the present embodiment and embodiment 3 lies in that, in this embodiment, the substrate 2 is provided with an auxiliary installation structure 25 formed integrally to facilitate the installation of the product. Specifically, in this embodiment, the auxiliary installation structure 25 comprises lugs symmetrically arranged at the two ends of the substrate 2 in the longitudinal direction of the substrate. In other optional embodiments, the auxiliary installation structure 25 could be adjusted as required, which is not limited herein.