CN217425676U

CN217425676U - Mixed solid-state laser radar

Info

Publication number: CN217425676U
Application number: CN202221057388.5U
Authority: CN
Inventors: 张洪奇; 高健; 李金鹏; 徐卫
Original assignee: Tianjin Jietai Gaoke Sensing Technology Co ltd
Current assignee: Tianjin Jietai Gaoke Sensing Technology Co ltd
Priority date: 2022-05-06
Filing date: 2022-05-06
Publication date: 2022-09-13
Anticipated expiration: 2032-05-06

Abstract

The utility model relates to a laser radar especially relates to a mix solid-state laser radar. A hybrid solid-state lidar comprising: the emitting part comprises a line light source and an emitting lens, and the emitting lens corrects emergent light of the line light source; the receiving part comprises a receiver, a negative lens and a positive lens which are arranged in sequence, wherein the receiving target surface length L of the receiver, the combined equivalent focal length f of the negative lens and the positive lens and the field angle theta have the relation of L/f = tg theta; and the rotating mirror is used for reflecting the emergent light of the emitting part and the reflected return light of the measured object. The utility model has the advantages that: through the design of the receiving mirror group, the equivalent focal length is far smaller than the actual space distance, and the volume of a receiving light path is greatly reduced.

Description

Mixed solid-state laser radar

Technical Field

The utility model relates to a laser radar especially relates to a mix solid-state laser radar.

Background

In the rapid development process of industrial automation, the photoelectric sensor plays an important role, and the laser radar is widely applied to the fields of measurement, protection and the like as a technical form of the photoelectric sensor.

The existing laser radar adopts near-infrared light sources, human eyes cannot see the light sources, and when the radar is installed, the problem of measurement error caused by the fact that the radar cannot be installed exists. Meanwhile, the volume of the device is made as small as possible in order to be matched with other equipment for installation.

At present, the hybrid solid-state laser radar mainly includes two types of MEMS and a rotating mirror in the scanning mode. The MEMS is in a form of two-dimensional galvanometer scanning simultaneously, is limited by the scanning angle range of the device, and needs multiple groups of receiving, transmitting and splicing if large-angle scanning is to be realized; the rotating mirror type is a one-to-one correspondence relationship of transmitting and receiving quantity at present, and the lens is a three-piece type Gaussian lens group, so that the volume structure is large. And at present above-mentioned laser radar all does not have the instruction light, adjusts inconvenient during the installation.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that overcome exist among the prior art not enough, provide a mix solid-state laser radar.

The utility model discloses a realize through following technical scheme:

a hybrid solid state lidar, comprising:

the emitting part comprises a line light source and an emitting lens, and the emitting lens corrects emergent light of the line light source;

the receiving part comprises a receiver, a negative lens and a positive lens which are arranged in sequence, wherein the receiving target surface length L of the receiver, the combined equivalent focal length f of the negative lens and the positive lens and the field angle theta have the relation of L/f = tg theta;

and the rotating mirror is used for reflecting the emergent light of the emitting part and the reflected return light of the measured object.

According to the above technical solution, preferably, the number of lines of the linear light source is smaller than the number of lines of the receiver, and the linear light source is located within the focal length of the emission lens.

According to the above technical solution, preferably, the turning mirror includes an emitting layer and a receiving layer, and a light-shielding plate is disposed between the emitting layer and the receiving layer.

According to the technical scheme, preferably, the number of other reflecting surfaces of the rotating mirror is greater than or equal to two, and a window mirror cover is arranged outside the rotating mirror.

According to the above technical solution, preferably, the rotating mirror is connected to a rotating part of a rotating motor, and a body of the rotating motor is fixedly connected to an external bracket.

According to the above technical solution, preferably, the laser irradiation device further comprises an indicating part, the indicating part comprises a visible laser source and an indicating lens, and the center of the indicating light of the visible laser source and the center of the emergent light of the linear light source are located on the same horizontal plane.

The utility model has the advantages that:

1. through the design of the receiving lens group, the equivalent focal length is far smaller than the actual space distance, and the volume of a receiving light path is greatly reduced;

2. the size of a transmitting device is reduced by the design of transmitting and receiving in a non-one-to-one correspondence mode, so that the volume of a transmitting light path is optimized by adopting a short-focal-length lens design;

3. the rotating mirror is matched with the light-isolating plate, so that the transmitting and receiving light path is effectively and completely isolated, and interference signals and measurement jitter caused by stray light are solved;

4. the structural design with the indicating light is convenient to install.

Drawings

Fig. 1 shows a schematic diagram of the size, focal length and field of view structure of a target surface according to an embodiment of the present invention.

Fig. 2 shows a schematic diagram of the principle of the optical path of the telephoto lens group according to the embodiment of the present invention.

Fig. 3 shows a schematic view of a telephoto receiver set according to an embodiment of the present invention.

Fig. 4 shows a schematic view of an embodiment of the invention with the light emitting surface placed at the focus.

Fig. 5 shows a schematic view of a light emitting surface of an embodiment of the invention placed in front of the focus.

Fig. 6 shows a schematic view of a rotating light path of a rotating mirror according to an embodiment of the present invention.

Fig. 7 shows a schematic front view structure diagram of an embodiment of the present invention.

In the figure: 1. the device comprises a line light source, 2 an emission lens, 3 an indicating part, 4 an optical isolation plate, 5 a receiver, 6 a negative lens and a positive lens, and 7 a rotating mirror.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the present invention will be further described in detail with reference to the accompanying drawings and preferred embodiments.

As shown in the figure, the utility model relates to a mix solid-state laser radar, include:

the emitting part is used for emitting light. The emitting part includes a line light source and an emitting lens. The line light source is composed of a plurality of lasers, such as vertical cavity surface emitting lasers (vcsels), arranged along a line. Emergent light emitted by the linear light source is collimated by the emitting lens to form linear light spots in the vertical direction in the drawing. The linear light spots are reflected by the rotating mirror to form a large-field area light source formed by splicing a plurality of linear light spot detection sections, and the large-field area light source irradiates a measured object after being transmitted by the window mirror cover. The relationship among the size of the light emitting surface of the emitting part, the focal length of the emitting lens and the light emitting angle is similar to that of the receiving light path.

The receiving part is used for receiving the reflected return light of the measured object. The receiving part comprises a receiver, a negative lens and a positive lens which are sequentially arranged, and whether a reflector is used for turning the light path or not can be selected according to a specific structure. The receiver may employ either linear SiPM or linear SPAD. The negative lens and the positive lens form a telephoto type double lens combination. As shown in fig. 1, the relationship between the receiving target surface length L of the receptor, the combined equivalent focal length f of the negative lens and the positive lens, and the field angle θ is L/f = tg θ. Generally, the field angle is a design index of a product, the angular resolution is higher when the number of the emitting part linear light sources (linear array SPAD or SiPM) is larger, but the size of a corresponding receiving target surface is larger. In order to increase the number of lines without changing the angle of view, this can generally only be achieved by increasing the focal length of the receiving lens. The invention uses a telephoto type double-lens combined lens, the principle of the light path is shown in figure 2, and the telephoto type double-lens combined lens is composed of a positive lens far away from a receiver and a negative lens near a receiving element, so that the equivalent focal length is far less than the actual space distance, and the volume of the receiving light path is greatly reduced. Furthermore, a reflector turning light path can be added between the lens group and the receiver to improve the space utilization rate. The reflected light of the object to be measured passes through the window mirror cover to the rotating mirror, is reflected to a receiving mirror group consisting of a negative lens and a positive lens by the rotating mirror, and is converged to a receiver by the receiving lens.

The emitting line number and the receiving line number are not in one-to-one correspondence, and the line number of the line light source is smaller than that of the receiver, so that the size of a light emitting surface is reduced, and further, under the condition of the same light emitting angle, the light emitting device can be realized by using a shorter focal length, and the light path of an emitting part is reduced. Further, as shown in fig. 4 and 5, and the linear light source is located within the focal length of the emission lens, the light beam is output in a more divergent manner, and a correspondingly larger light-emitting angle is obtained. Therefore, the effect of covering a full receiving field of view can be achieved under the condition of less transmitting lines, and the volume of a transmitting light path is further reduced. Similarly, a reflector can be added between the emission lens and the linear VCSEL to improve the space utilization rate.

The rotating mirror can be a reflecting mirror, and four surfaces or other reflecting surfaces not less than two are adopted. A window mirror cover is arranged outside the rotating mirror. When the horizontal field of view is large when the rotating mirror needs to be rotated, the transmitting or receiving lens cannot be tightly attached to the rotating mirror, as shown in fig. 6, otherwise, light rays are blocked. The larger the horizontal field of view is, the farther the lens is from the rotating mirror, and an unsealed space is generated in the middle, so that a small amount of emitted scattered light in the upper half part enters a receiving light path, and false operation or measurement jitter of signals is caused. The rotating mirror comprises an emitting layer and a receiving layer, and an opaque light-shielding plate is arranged between the emitting layer and the receiving layer. The emitting part and the emitting layer are positioned on one side (namely, an emitting side) of the light-isolating plate, and the receiving part and the receiving layer are positioned on the other side (namely, a receiving side) of the light-isolating plate. The optical paths of the transmitting side and the receiving side are parallel. The light-shielding plate completely isolates stray light between the transmitting side and the receiving side, and interference signals and measurement jitter caused by the stray light are solved. The angles of the four reflecting surfaces of the rotating mirror in the vertical direction can be parallel to the rotating shaft, and can also form four angles of +2 theta, + theta, -theta and-2 theta with the rotating shaft respectively, or can be the same with the angles of two opposite surfaces, and the angles of two adjacent surfaces are respectively + theta and-theta.

The rotating mirror is connected with a rotating part of the rotating motor, and a body of the rotating motor is fixedly connected with an external bracket. The rotary motor is provided with a code disc scale mark, and the time sequence positioning function of images is realized by matching with an encoder. A through groove is formed between the transmitting layer and the receiving layer, a part of the light isolating plate is inserted into the through groove, and the light isolating plate is fixedly connected with an external support.

The laser indicator further comprises an indicating part, and the indicating part comprises a visible laser source and an indicating lens. The visible laser source can adopt a red LD laser module to output a point light source. The centers of the red laser tube and the emergent light of the line light source are positioned on the same horizontal plane. The red laser emitted by the red laser tube is collimated by the indicating lens and then reflected by the rotating mirror, so that the red laser (namely indicating light) is positioned at the central line position of the vertical view field and is used as a scanning plane formed by scanning of the indicating near-infrared laser during installation, and the accuracy of installation and measurement and the convenience of installation operation are greatly improved.

The working principle of the embodiment is as follows: the transmitting part consists of a linear array VCSEL, a mirror bracket and a transmitting lens (a reflector can be added in a light path). Emergent light is collimated by the lens to form linear light spots in the vertical direction, and is reflected by the rotating mirror to form a large-field-of-view area light source formed by splicing a plurality of linear light spot detection sections, and the large-field-of-view area light source irradiates a measured object after being transmitted by the window mirror cover. The transmitting lens is a single-chip or multi-chip aspheric or spherical mirror.

The receiving part consists of a linear array SiPM (or linear array SPAD), a spectacle frame and a telephoto type receiving mirror group (a reflector can be added in an optical path). The light reflected by the object passes through the outer window mirror cover to the rotating mirror, is reflected to the receiving mirror group by the rotating mirror, and is converged to the linear array SiPM (or linear array SPAD) by the receiving lens. The telephoto lens group consists of two aspheric or spherical lenses, a positive lens far away from the receiver and a negative lens close to the receiver; a narrow-band filter corresponding to the emission wavelength can be added in the receiving light path to reduce the interference problem of the ambient light.

The rotating mirror part is composed of four-side reflecting mirrors (the number of reflecting surfaces can be more than or equal to two) and a rotating motor. The rotating mirror is divided into an upper layer and a lower layer for transmitting and receiving, and an inwards concave groove is arranged at the interface and can be matched with the light baffle plate to realize the complete isolation of transmitting and receiving light paths. The interior of the rotating mirror is of a hollow structure, a motor can be embedded into the rotating mirror for installation, the lower edge of the rotating mirror is provided with a code disc scale mark, and the time sequence positioning function of images is realized by matching with an encoder.

The isolation structure is two light isolation plates formed by splicing around the groove of the rotating mirror, and the complete isolation of the transmitting and receiving light path is realized.

The indicating part consists of a red laser tube and a lens. The red laser tube is collimated by the lens, reflected by the rotating mirror, is positioned on the same horizontal plane with the emergent light at the center of the linear array VCSEL and is used as a scanning plane for indicating the near infrared laser scanning during installation, and therefore the accuracy of installation and measurement and the convenience of installation operation are greatly improved.

The utility model has the advantages that:

4. the structural design with the indicating light is convenient to install.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A hybrid solid state lidar, comprising:

2. A hybrid solid state lidar according to claim 1, wherein the number of lines of the line source is less than the number of lines of the receiver, the line source being located within the focal length of the transmitting lens.

3. A hybrid solid state lidar according to claim 1, wherein the turning mirror comprises a transmitting layer and a receiving layer with an optically isolating plate disposed therebetween.

4. A hybrid solid state lidar according to claim 3, wherein the transmitting layer and the receiving layer of the rotating mirror are integrally formed, an annular groove is provided between the transmitting layer and the receiving layer, and the light barrier is inserted into the annular groove.

5. A hybrid solid state lidar according to claim 1, wherein the number of other reflecting surfaces of the rotating mirror is greater than or equal to two, and a window mirror cover is provided outside the rotating mirror.

6. A hybrid solid state lidar according to claim 1, wherein the angle of the reflecting surface of the turning mirror in the vertical direction may be parallel to the axis of rotation or may be one of +2 θ, + θ, - θ or-2 θ, θ being the field angle.

7. A hybrid solid state lidar according to claim 1, wherein the rotating mirror is coupled to a rotating portion of a rotating motor, and a body of the rotating motor is fixedly coupled to an external support.

8. The hybrid solid-state lidar according to claim 1, further comprising an indicating portion comprising a visible laser source and an indicating lens, wherein the center of the indicating light of the visible laser source and the center of the outgoing light of the line light source are located at the same horizontal plane.