CN214149152U

CN214149152U - One-way micro-displacement detection device based on light spot image

Info

Publication number: CN214149152U
Application number: CN202022995918.8U
Authority: CN
Inventors: 王德麾; 姜世平; 董小春; 杨武; 谢伟民
Original assignee: Sichuan Windom Photoelectric Technology Co ltd
Current assignee: Sichuan Windom Photoelectric Technology Co ltd
Priority date: 2020-12-14
Filing date: 2020-12-14
Publication date: 2021-09-07
Anticipated expiration: 2030-12-14

Abstract

The utility model provides a one-way micro-displacement detection device based on facula images, which comprises a laser and a digital camera, wherein a beam splitter is arranged on the emergent light path of the laser; a collimating objective, a front lens and a measured object reflector are sequentially arranged on a reflecting light path of the beam splitter; the reflected light path of the reflector of the measured object reaches the beam splitter through the front lens and the collimating objective lens in sequence, and enters the digital camera after being transmitted by the beam splitter; the measured object reflector is provided with a plurality of circular grating stripes, and the extension lines of the circular grating stripes are intersected at one point. The utility model discloses an operating principle is absolute type and measures, can not produce and add up the error to use reflective circular grating, can be the metal material, also can be suitable for the glass material.

Description

One-way micro-displacement detection device based on light spot image

Technical Field

The utility model relates to a micrometric displacement detects technical field, particularly, relates to an one-way micrometric displacement detection device based on facula image.

Background

In the field of translational distance measurement, a grating ruler, also called a grating ruler displacement sensor (grating ruler sensor), is generally used in industry. Which is a measurement feedback device that works using the optical principle of the grating. Grating scales are often applied to closed-loop servo systems of numerically controlled machine tools and can be used for detecting linear displacement or angular displacement. The signal output by the sensor is digital pulse, and the sensor has the characteristics of large detection range, high detection precision and high response speed. For example, in a numerically controlled machine tool, it is common to detect the coordinates of the tool and the workpiece to observe and track the feed error, so as to compensate for the motion error of the tool. The grating scale is divided into a transmission grating and a reflection grating according to different manufacturing methods and optical principles.

The grating ruler consists of two parts, namely a ruler grating and a grating reading head. The key part of the grating detection device is a grating reading head which comprises a light source, a convergent lens, an indication grating, a photoelectric element, an adjusting mechanism and the like. The grating reading head has a plurality of structural forms, and is divided into direct receiving type reading heads (or called silicon photocell reading heads, mirror type reading heads, beam splitting mirror type reading heads and metal grating reflection type reading heads) according to the structural characteristics and the using occasions of the reading head.

However, the ruler grating in the precise grating ruler has high precision, high manufacturing cost and long manufacturing period; at the same time, the manufacture of the grating read head is complicated. The whole assembly and adjustment process of the precise grating ruler is very complex and can be implemented by a skilled assembly and adjustment technician seriously.

In high vibration and high impact application occasions, a glass grating device is not generally used, a reflective non-light-transmission metal grating device is preferred, and the manufacturing cost of a precise metal grating is high.

Disclosure of Invention

The utility model aims at providing an one-way micro displacement detection device based on facula image to solve the above-mentioned problem that adopts traditional grating chi to carry out micro displacement detection to exist.

The utility model provides a one-way micro-displacement detection device based on facula images, which comprises a laser and a digital camera, wherein a beam splitter is arranged on the emergent light path of the laser; a collimating objective, a front lens and a measured object reflector are sequentially arranged on a reflecting light path of the beam splitter; the reflected light path of the reflector of the measured object reaches the beam splitter through the front lens and the collimating objective lens in sequence, and enters the digital camera after being transmitted by the beam splitter; the measured object reflector is provided with a plurality of circular grating stripes, and the extension lines of the circular grating stripes are intersected at one point.

In one embodiment, the working surface of the beam splitter forms an angle of 45 ° with the exit optical path of the laser.

In one embodiment, the working surface of the beam splitter and the reflecting surface of the measured object reflector form an included angle of 45 degrees.

In one embodiment, the working surface of the beam splitter is at an angle of 45 ° to the receiving mirror surface of the digital camera.

In one embodiment, the digital camera is a CCD camera.

In one embodiment, the object reflector is made of glass.

In one embodiment, the reflector of the object to be measured is made of metal.

To sum up, owing to adopted above-mentioned technical scheme, the beneficial effects of the utility model are that:

1. the utility model discloses an one-way micrometric displacement detection device based on facula image's theory of operation is absolute formula measurement, can not produce and add up the error.

2. The utility model discloses an one-way micro displacement detection device based on facula image uses reflective circular grating, can be the metal material, also can be suitable for the glass material.

3. The utility model discloses an one-way micrometric displacement detection device based on facula image uses macroscopic diffraction facula pattern to measure, and data readout device uses general optics technique can realize, and preparation assembly cycle and cost are all preferred.

4. The utility model discloses a reflective circular grating's that one-way micrometric displacement detection device used based on facula image interval is less to final measuring result influence, can use great interval grating to realize, can reduce preparation and assembly cost, time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive efforts.

Fig. 1 is the structure schematic diagram of the unidirectional micro-displacement detection device based on the light spot image.

Fig. 2 is the structure schematic diagram of the reflective circular grating of the unidirectional micro-displacement detection device based on the light spot image of the present invention.

Fig. 3 is the utility model discloses a position and diffraction facula pattern sketch map in the application example of facula image based one-way micro displacement detection device.

Icon: 1-laser, 2-beam splitter, 3-collimating objective, 4-front lens, 5-measured object reflector and 6-digital camera.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Examples

Referring to fig. 1, the embodiment provides a one-way micro-displacement detection device based on a light spot image, which includes a laser 1 and a digital camera 6, wherein a beam splitter 2 is arranged on an emergent light path of the laser 1; a collimating objective 3, a front lens 4 and a measured object reflector 5 are sequentially arranged on a reflection light path of the beam splitter 2; the reflected light path of the measured object reflector 5 sequentially passes through the front lens 4 and the collimating objective 3 to reach the beam splitter 2, and enters the digital camera 6 after being transmitted by the beam splitter 2; referring to fig. 2, the measured object reflector 5 is provided with a plurality of circular grating stripes, and the extension lines of the circular grating stripes are intersected at one point.

That is, the utility model provides a reflection-type circular grating carries out the micro displacement and detects. The material of the measured object reflector 5 may be glass or metal, on which circular grating stripes are printed or stamped, and the extension lines of each circular grating stripe are all intersected at one point (i.e. the central point of the circular grating), see fig. 2.

Application example:

the unidirectional micro-displacement detection device is installed according to the structure, and the included angle between the working surface of the beam splitter 2 and the emergent light path of the laser 1 is 45 degrees; the included angle between the working surface of the beam splitter 2 and the reflecting surface of the measured object reflecting mirror 5 is 45 degrees; the included angle between the working surface of the beam splitter 2 and the receiving mirror surface of the digital camera 6 is 45 degrees; thereby forming the unidirectional micro-displacement detection device shown in fig. 1, and the digital camera 6 adopts a CCD camera.

The measured object reflector 5 is arranged on the measured object, when the measured object reflector 5 generates micro displacement along the moving direction, the grating interference pattern shot by the digital camera 6 can rotate, and the actual moving distance can be measured by measuring the rotating value. Specifically, the method comprises the following steps:

referring to fig. 2, when the object reflector 5 is at the position 1 and the position 2, the spatial absolute position of the measurement point of the unidirectional micro-displacement detection device is unchanged, so that the relative position of the measurement point on the object reflector 5 is changed, and since the object reflector 5 adopts a circular grating, the diffraction light spot patterns shown in fig. 3 are respectively generated at the position 1 and the position 2 (a straight line formed by diffraction light spots of multiple levels, and the patterns diffracted at different positions rotate), and the movement distance information can be obtained by identifying and measuring the diffraction light spot patterns.

If a calibration method is adopted, diffraction light spot patterns are recorded in advance at a plurality of standard moving distance positions to form a pattern database; when the unidirectional micro-displacement detection device is actually applied to micro-displacement detection, the shot diffraction light spot patterns are directly compared with the diffraction light spot patterns in the pattern database, the closest diffraction light spot patterns in the pattern database are found out, and the closest moving distance information is obtained; furthermore, a measurement result with higher precision can be obtained by an interpolation mode.

In view of the above, the utility model discloses an one-way micrometric displacement detection device based on facula image has following beneficial effect:

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A unidirectional micro-displacement detection device based on a facula image is characterized by comprising a laser (1) and a digital camera (6), wherein a beam splitter (2) is arranged on an emergent light path of the laser (1); a collimating objective lens (3), a front lens (4) and a measured object reflector (5) are sequentially arranged on a reflection light path of the beam splitter (2); the reflected light path of the measured object reflector (5) sequentially passes through the front lens (4) and the collimating objective lens (3) to reach the beam splitter (2), and enters the digital camera (6) after being transmitted by the beam splitter (2); the measured object reflector (5) is provided with a plurality of circular grating stripes, and the extension lines of the circular grating stripes are intersected at one point.

2. The device for detecting the unidirectional micro-displacement based on the facula image according to claim 1, wherein the included angle between the working surface of the beam splitter (2) and the emergent light path of the laser (1) is 45 degrees.

3. The device for detecting the unidirectional micro-displacement based on the facula image according to claim 2, characterized in that the included angle between the working surface of the beam splitter (2) and the reflecting surface of the measured object reflector (5) is 45 °.

4. The device for detecting the unidirectional micro-displacement based on the facula image according to claim 3, characterized in that the included angle between the working surface of the beam splitter (2) and the receiving mirror surface of the digital camera (6) is 45 degrees.

5. The unidirectional micro-displacement detection device based on the light spot image according to claim 4, wherein the digital camera (6) is a CCD camera.

6. The device for detecting the unidirectional micro-displacement based on the light spot image according to claim 1, wherein the measured object reflector (5) is made of glass.

7. The device for detecting the unidirectional micro-displacement based on the light spot image according to claim 1, wherein the measured object reflector (5) is made of metal.