CN108051880B - Method for processing metal multi-face scanning prism - Google Patents

Abstract

The invention discloses a method for processing a metal multi-face scanning prism, belongs to the technical field of optical processing, and particularly relates to a method for processing a multi-face scanning prism, aiming at solving the problem of low angle precision between each face when the multi-face scanning prism is processed in the prior art. The use of the technical scheme can be independent of a high-precision numerical control rotating shaft, the processing of the metal multi-surface scanning prism can be completed on a two-shaft machine tool, and the processing efficiency, the processing precision and the processing consistency are greatly improved.

Description

A kind of processing method of metal multi-faceted scanning prism

technical field

The invention belongs to the technical field of optical processing, and in particular relates to a processing method of a multi-faceted scanning prism.

Background technique

The multi-sided scanning prism has multiple reflective surfaces and is the core optical device in laser equipment such as scanners, copiers, and code scanners. When in use, it is usually installed on the rotating shaft of the motor. Through the high-speed rotation of the multi-faceted scanning prism, a wide-range, ultra-high-speed, high-precision and high-repeat laser beam scanning can be achieved. The angle accuracy, surface quality and other factors will directly affect the scanning. Therefore, the angular machining accuracy of each reflective surface is required to be very high.

At present, the machining of multi-faceted scanning prisms in China is mainly realized by CNC lathes with rotating shafts. The number of machining at one time is limited, and the angular accuracy between each surface is guaranteed by the accuracy of the numerical control rotating shafts. The problems are low processing efficiency and difficult cost. The control and angle accuracy are poor, and the scanning effect is not good; in addition, the product consistency during batch processing is poor, which seriously affects the stability of the assembly equipment.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problem that the angle precision between the faces of the multi-faceted scanning prism in the prior art is difficult to control.

A processing method of a metal multi-faceted scanning prism, the specific technical scheme is as follows:

1) Steps of processing the standard block: processing a polyhedral prism whose precision is better than the design parameters of the metal polyhedral scanning prism as the standard block;

2) Install and fix the standard block on the rotating shaft of the electric control turntable, wherein the normal direction of the cross section of the standard block is parallel to the rotating shaft of the electric control turntable;

3) The metal polygonal scanning prism embryo to be processed is also clamped on the rotating shaft of the electronically controlled turntable, wherein the normal direction of the cross-section of the metal polygonal scanning prism embryo is parallel to the rotation axis of the electronically controlled turntable;

4) Build a self-collimating optical path on the machine tool, install the electronically controlled turntable on the machine tool worktable, rotate the electronically controlled turntable, align any side of the standard block with the self-collimating optical path, and use a locking mechanism Fixing the rotating shaft of the electronically controlled turntable; turning a scanning surface on the metal multi-faceted scanning prism blank;

5) Rotate the electronically controlled turntable, align the other sides of the standard block with the self-collimating optical path in turn, and turn the remaining scanning surfaces on the metal polygonal scanning prism blank.

The machine tool of this processing method can be completed by the flying tool turning technology of two-axis or more single-point diamond lathes. In order to reduce the cutting amount, the metal polyhedral scanning prism blank can be made into a metal polyhedron with an angle error of less than 2 degrees, and then directly turned into an optical surface by the diamond flying knife turning technology according to the above technical scheme.

The above technical solution can also be turned on a long metal polygonal scanning prism embryo, and after all sides of the belt are processed, a plurality of metal polygonal scanning prisms can be directly obtained through a cutting process.

In the above technical solution, the standard block is a glass polygonal prism whose precision is better than the design parameters of the metal polygonal scanning prism.

In the above technical solution: the glass polygonal prism can be processed by conventional cold working methods, and the angle error and tower difference between the surfaces are strictly controlled when processing the standard block.

In the above technical solution, the standard block is provided with a through hole, and the through hole on the standard block is assembled and fixed in a coaxial manner with the rotating shaft of the electric control turntable.

In the above technical solution: the mirror blank of the multi-faceted metal scanning rotating mirror to be processed is also provided with a through hole, which penetrates into the rotating shaft of the electronically controlled turntable.

In the above technical solution: the self-collimating light path is a self-collimating collimated light pipe.

Preferred solution: the self-collimating light is composed of a parallel light laser, a beam splitter, a plane mirror, and an image screen, wherein the parallel light emitted by the parallel beam laser is incident on the beam splitter, and the light reflected by the beam splitter is placed vertically as a reference light After being reflected by the plane reflector in the optical path, it is incident on the image screen, and the light transmitted by the beam splitter is incident on any side of the standard block as detection light; when the electronically controlled turntable is rotated, the detection light is reflected by the side to the image screen, Form interference fringes on the image screen. The optical path is actually a Michelson interference optical path, and the rotation angle of the electric turntable can be controlled more precisely through the interference fringes.

The image screen can also be replaced with a CCD, and the interference fringes of the reference light and the detection light can be imaged in the CCD, and the changes of the interference fringes can be monitored in real time during the whole process. In this way, it is more convenient to observe whether the rotating shaft of the electronically controlled turntable is rotated during the processing.

The real-time change information of the interference fringes can also be fed back to the machine tool for real-time error compensation when turning with the machine tool. Such processing is a closed-loop processing process, which can be converted into the attitude change of the rotating shaft of the electronically controlled turntable through the change of the interference fringe, and the real-time change information is fed back to the processing machine tool, which can further improve the processing accuracy.

In order to adapt to batch processing, a more optimal solution is: in the above technical solution, the rotating shaft of the electronically controlled turntable described in step 2) is connected with several driven rotating shafts through a linkage mechanism, and each driven rotating shaft can be clamped At least one metal polygonal scanning prism embryo, when the rotating shaft of the electronically controlled turntable rotates, the driven rotating shaft also rotates by the same angle; in the above-mentioned step 3), a plurality of metal polygonal scanning prism embryos to be processed are installed and clamped at the same time. On the driven rotating shaft; in the above step 4), rotate the electronically controlled turntable, align any side of the standard block with the self-collimating optical path, and fix the rotating shaft of the electronically controlled turntable and all the slaves with a locking mechanism. A moving rotating shaft; a scanning surface is turned on the metal multi-faceted scanning prism blank fixed on the rotating shaft of the electronically controlled turntable and the driven rotating shaft. In this way, multiple metal polygonal scanning prism blanks to be processed can be installed on each rotating shaft, and multiple driven rotating shafts can be connected through the linkage device, so that batch processing can be realized, and the same batch of products can also be guaranteed to have the same precision. Greatly improves the stability of the assembled product.

Description of drawings

Fig. 1 Schematic diagram of processing of metal multi-faceted scanning prism;

Figure 2 Schematic diagram of multi-axis batch processing of metal multi-faceted scanning prisms;

3 is a schematic diagram of a self-collimating optical path;

Among them: 1- electronically controlled turntable, 2-standard block, 3-metallic multi-faceted scanning prism blank, 4-rotating shaft of electronically controlled turntable, 5-self-collimating optical path, 6-electronically controlled turntable bracket, 7-locking mechanism, 8- linkage mechanism, 9- driven shaft, 10- parallel light laser, 11- beam splitter, 12- reference light, 13- detection light, 14- plane mirror, 15- image screen.

Detailed ways

In order to illustrate the invention more clearly, further description is given below in conjunction with the accompanying drawings and embodiments

Example 1:

The processing method of a kind of metal polygonal scanning prism shown in accompanying drawing 1, the concrete technical scheme is as follows:

1) Steps of processing the standard block: processing a polygonal prism whose precision is better than the design parameters of the metal polygonal scanning prism as the standard block 2;

2) Install and fix the standard block on the rotating shaft 4 of the electronically controlled turntable 1, wherein the normal direction of the cross-section of the standard block is parallel to the rotating shaft of the electronically controlled turntable;

3) the metal multi-faceted scanning prism embryo 3 to be processed is also clamped on the rotating shaft of the electronically controlled turntable, wherein the normal direction of the cross-section of the metal multi-faceted scanning prism embryo is parallel to the axis of rotation of the electronically controlled turntable;

4) Build the self-collimating optical path 5 on the machine tool, install the electronically controlled turntable on the machine tool table, rotate the electronically controlled turntable, align any side of the standard block with the self-collimating optical path, and lock the The mechanism fixes the rotating shaft of the electronically controlled turntable; a scanning surface is turned on the metal multi-faceted scanning prism blank;

5) Rotate the electronically controlled turntable, align the other sides of the standard block with the self-collimating optical path in turn, and turn the remaining scanning surfaces on the metal polygonal scanning prism blank.

Embodiment 2:

The processing method of a kind of metal polygonal scanning prism shown in accompanying drawing 2, the concrete technical scheme is as follows:

1) Steps of processing the standard block: processing a polygonal prism whose precision is better than the design parameters of the metal polygonal scanning prism as the standard block 2;

2) Install and fix the standard block on the rotating shaft 4 of the electronically controlled turntable 1, wherein the normal direction of the cross section of the standard block is parallel to the rotating shaft of the electronically controlled turntable; The rotating shaft 9 is connected, and at least one metal polygonal scanning prism blank 3 can be clamped on each driven rotating shaft. When the rotating shaft of the electronically controlled turntable rotates, the driven rotating shaft also rotates by the same angle;

3) Clamping a plurality of metal polygonal scanning prism embryos to be processed on the driven rotating shaft; wherein the normal direction of the cross section of the metal polygonal scanning prism embryo is parallel to the rotation axis of the electronically controlled turntable;

4) Build the self-collimating optical path 5 on the electronically controlled turntable support 6, install the electronically controlled turntable on the machine tool table, rotate the electronically controlled turntable, and align any side of the standard block with the self-collimating optical path, The rotating shaft of the electronically controlled turntable and all the driven rotating shafts are fixed by the locking mechanism 7; the scanning surface is turned on the metal multi-sided scanning prism blank fixed on the rotating shaft and the driven rotating shaft of the electronically controlled turntable.

5) Rotate the electronically controlled turntable, align the other sides of the standard block with the self-collimating optical path in turn, and turn the remaining scanning surfaces on the metal polygonal scanning prism blank.

Embodiment three:

Based on the technical solution of the first embodiment, the self-collimating optical path 5 is shown in FIG. 3 and consists of a parallel light laser 10, a beam splitter 11, a plane mirror 14, and an image screen 15, wherein the parallel light emitted by the parallel light laser Incident to the beam splitter, the light reflected by the beam splitter as the reference light 12 is reflected by a plane mirror placed vertically in the optical path and then incident on the image screen, and the light transmitted by the beam splitter is incident on any side of the standard block as the detection light 13 ; Rotate the electronically controlled turntable, the detection light is reflected by the side to the image screen 15, and interference fringes are formed on the image screen. The optical path is actually a Michelson interference optical path, and the rotation angle of the electric turntable can be controlled more precisely through the interference fringes.

The principle of the above-mentioned technical solution is that the rotation angle of the rotating shaft is precisely controlled by the self-collimating optical path and the standard block. Since the to-be-processed metal polygonal scanning prism blank and the standard block are clamped on the same rotating shaft, each standard block can be accurately copied. The angular accuracy of the sides. The use of the technical solution can be independent of the high-precision CNC rotating shaft, and the metal multi-faceted scanning prism can be processed on a two-axis machine tool, thereby greatly improving the processing efficiency, processing accuracy and processing consistency.

This technical solution is not only applicable to multi-faceted scanning prisms, but also to multi-faceted special-shaped prisms. For example, the sides of the prisms are spherical or aspherical. In order to precisely control the optical axis direction of each face of the multi-faceted special-shaped prism, it is also possible to process each face to be a plane first. The optical axis angle of the standard block is the same as the optical axis angle of the multi-face special-shaped prism, and the optical axis angle of the standard block is copied to the multi-face special-shaped prism through the technical solution.

The part of the technical solution that is not described in detail belongs to the well-known technology of those skilled in the art.

Claims (10)

1. A method for processing a metal multi-face scanning prism comprises the following steps:

1) and (3) processing a standard block: processing a polygon prism with precision superior to the design parameters of the metal polygon scanning prism as a standard block;

2) the standard block is fixedly arranged on a rotating shaft of the electric control rotary table, wherein the normal direction of the cross section of the standard block is parallel to the rotating shaft of the electric control rotary table;

3) clamping a metal multi-surface scanning prism mirror blank to be processed on a rotating shaft of the electric control rotary table, wherein the normal direction of the cross section of the metal multi-surface scanning prism mirror blank is parallel to the rotating shaft of the electric control rotary table;

4) building an auto-collimation light path on a machine tool, installing an electric control rotary table on a machine tool workbench, rotating the electric control rotary table, aligning any one side surface of the standard block with the auto-collimation light path, and fixing a rotating shaft of the electric control rotary table by using a locking mechanism; turning a scanning surface on the metal multi-surface scanning prism mirror blank;

5) and rotating the electric control rotary table, sequentially aligning other side surfaces of the standard block to the auto-collimation light path, and turning the rest scanning surfaces on the metal multi-surface scanning prism lens blank.

2. The method of claim 1, wherein: the standard block is a glass multi-face prism with precision superior to the design parameters of a metal multi-face scanning prism.

3. The method of claim 2, wherein: the glass multi-face prism is processed by a cold processing method, and angle errors and tower difference among all surfaces are strictly controlled when the standard block is processed.

4. The method of claim 1, wherein: the standard block is provided with a through hole, and the through hole on the standard block is assembled and fixed in a coaxial mode with a rotating shaft of the electric control turntable.

5. The method of claim 4, wherein: the metal multi-surface scanning rotating mirror blank to be processed is also provided with a through hole which penetrates through a rotating shaft of the electric control rotating table.

6. The method for processing a metal polygon scanning prism according to any one of claims 1 to 5, wherein: the auto-collimation light path is an auto-collimation parallel light tube.

7. The method for processing a metal polygon scanning prism according to any one of claims 1 to 5, wherein: the auto-collimation light path consists of a parallel light laser, a beam expander, a spectroscope, a plane reflector and an image screen, wherein parallel light emitted by the parallel light laser is incident to the spectroscope after being subjected to beam expansion, light reflected by the spectroscope is incident to the image screen after being reflected by the plane reflector vertically placed in a light path as reference light, and light transmitted by the spectroscope is incident to any one side surface of the standard block as detection light; and rotating the electric control turntable, and reflecting the detection light to the image screen by the side surface to form interference fringes on the image screen.

8. The method of claim 7, wherein: the CCD is used for replacing an image screen, interference fringes of the reference light and the detection light are imaged in the CCD, and the change of the interference fringes is monitored in real time in the whole processing process.

9. The method of claim 8, wherein: and when the lathe is used for turning, feeding back the real-time change information of the interference fringes to the lathe for error real-time compensation.

10. The method for processing a metal polygon scanning prism according to any one of claims 1 to 5, wherein: the rotating shaft of the electric control turntable in the step 2) is connected with a plurality of driven rotating shafts through a linkage mechanism, each driven rotating shaft can be clamped with at least one metal multi-surface scanning prism lens blank, and when the rotating shaft of the electric control turntable rotates, the driven rotating shafts also rotate by the same angle; clamping a plurality of metal multi-surface scanning prism lens blanks to be processed on the driven rotating shaft simultaneously in the step 3); rotating the electric control turntable in the step 4), aligning any one side surface of the standard block with an auto-collimation light path, and fixing a rotating shaft and all driven rotating shafts of the electric control turntable by using a locking mechanism; and turning scanning surfaces on metal multi-surface scanning prism mirror blanks fixed on a rotating shaft and a driven rotating shaft of the electric control turntable.

Images