CN114609773B

CN114609773B - High-power laser kude optical path debugging method

Info

Publication number: CN114609773B
Application number: CN202210140866.7A
Authority: CN
Inventors: 张健; 王令玮; 郑晓刚
Original assignee: Harbin Xinguang Photoelectric Technology Co ltd
Current assignee: Harbin Xinguang Photoelectric Technology Co ltd
Priority date: 2022-02-16
Filing date: 2022-02-16
Publication date: 2023-05-26
Anticipated expiration: 2042-02-16
Also published as: CN114609773A

Abstract

The invention relates to a high-power laser curde optical path debugging method, belongs to the technical field of curde optical path debugging, and is used for solving the defect that the curde optical path debugging method in the prior art cannot avoid the change of the laser spot position in the rotating process of a turntable. The method of the invention comprises the following steps: the reference mirror is arranged at the entrance position of the kude optical path; the beam splitter, the fixed focus lens and the first detector are sequentially arranged along an emergent light path, and the second detector is arranged on a reflection light path of the beam splitter; rotating the horizontal shaft, observing the cross position variation received by the first detector and the second detector, and controlling the cross position variation within a preset range by adjusting the first kude reflector and the second kude reflector; and rotating the pitching shaft, and controlling the cross position variation within a preset range by adjusting the third and fourth kude reflectors. One application of the present invention is in the debugging of high energy laser emitting systems.

Description

High-power laser kude optical path debugging method

Technical Field

The invention relates to the technical field of kude optical path debugging, in particular to a high-power laser kude optical path debugging method.

Background

Along with the continuous improvement of the output power of a semiconductor laser, the development wave of high-energy laser emission equipment is driven, the equipment has the characteristics of long working distance, high output energy, tracking and emission of a common light path, laser in a system is often transmitted into an emission lens through a Cook light path system, horizontal 360 DEG scanning and pitching 0 DEG to 90 DEG scanning are realized through rotation of the Cook light path, the traditional Cook light path is assembled and called into an imaging system, the optical axis angle can only be guaranteed not to change in the rotating process of a turntable, the position of a light beam can translate, the beam expansion rate of a telescopic subsystem in the high-energy laser system is generally larger, when the position of the laser beam transmitted through the Cook light path deviates, the position offset of a light spot on a main mirror is amplified according to the equal proportion of the beam expansion rate, the high-energy laser is led to exceed a reflecting surface of the main mirror, the system is damaged, and the position change condition of the laser light spot caused by rotation of the turntable is shown in fig. 1 (a) and fig. 1 (b). In which fig. 1 (a) shows the laser emission position when the device rotates to a certain position, and fig. 1 (b) shows the laser emission position when the device rotates to another position, it can be seen that the laser emission position moves upwards in the process, and the conventional debugging method cannot eliminate such problems.

Disclosure of Invention

The invention aims to solve the defect that the laser spot position change in the rotating process of a turntable cannot be avoided by the kude optical path debugging method in the prior art.

According to a first aspect of the present invention, there is provided a method for debugging a high-power laser kude optical path, wherein the kude optical path sequentially comprises a first kude reflector, a second kude reflector, a third kude reflector and a fourth kude reflector from an inlet to an outlet; the method comprises the following steps: the reference mirror is arranged at the entrance position of the kude optical path, so that the center cross of the reference mirror coincides with the position of the high-power laser incident axis, and the mirror surface of the reference mirror is perpendicular to the optical axis of the high-power laser; the beam splitter, the fixed focus lens and the first detector are sequentially arranged along an emergent light path, and the second detector is arranged on a reflection light path of the beam splitter; aligning an inner focusing telescope with a reference mirror, wherein the optical axis of the inner focusing telescope is auto-collimated with the plane of the reference mirror, and the center of the inner focusing telescope coincides with the cross center of the reference mirror; fixing a pitching axis of the turntable, rotating a horizontal axis, observing the cross position variation received by the first detector and the second detector, and enabling the cross position variation received by the first detector and the second detector to be respectively smaller than a first preset value and a second preset value when the horizontal axis of the turntable is rotated by adjusting the first kude reflector and the second kude reflector; fixing a horizontal axis of the turntable, rotating a pitching axis, observing the cross position variation received in the first detector and the second detector, and enabling the cross position variation received in the first detector and the second detector to be respectively smaller than a third preset value and a fourth preset value when the turntable pitching axis is rotated by adjusting a third kude reflector and a fourth kude reflector.

Preferably, the focal length of the fixed focus lens is 100mm.

Preferably, the first preset value is 1 pixel, and the second preset value is 10 pixels.

The invention has the technical effects that: 1. the optical axis angle is unchanged after the light beam is transmitted through the kude optical path, the optical axis position is unchanged, the system transmitting caliber is reduced, the optical axis angle of the system turntable is unchanged in the large-angle scanning process, and the system aiming precision and the system safety are improved. 2. The laser emission entrance reference mirror is aligned through the internal focusing telescope, the optical axis angle and the optical axis position of the kude optical path are monitored simultaneously through the two paths of detectors, the optical axis is overlapped with the rotating shaft of the turntable through adjusting the angle of the lens in the kude optical path, the optical axis angle change in the 360-degree rotation process of the horizontal axis after the adjustment is completed is smaller than 25 micro-arc degrees, the beam position change is smaller than 0.025 mm, the tracking and aiming precision of the system is improved, the jumping amount of light spots on the main mirror is reduced, the emission caliber of the system is reduced, and the safety of the high-power laser system is improved.

Other features of the present invention and its advantages will become apparent from the following detailed description of exemplary embodiments of the invention, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a schematic diagram of a laser spot position change generated by a prior art kude optical path debugging method; wherein fig. 1 (a) is a schematic view of the beam position when the turntable is at a certain rotation angle, and fig. 1 (b) is a schematic view of the beam position when the turntable is at another rotation angle;

FIG. 2 is a schematic view of the positional relationship between the optical path of kude and the horizontal and pitch rotation axes of the turntable; wherein A is a rotation shaft of a horizontal platform, and B is a pitching rotation shaft;

FIG. 3 is a schematic diagram showing the state of the system after the completion of steps S1 to S3;

FIG. 4 is a schematic diagram of turning the horizontal axis for debugging in step S4;

fig. 5 is a schematic diagram of turning the pitch axis for debugging in step S5.

Reference numerals illustrate:

1-first and second Cook mirror 2

3-third and fourth Cook mirror 4-fourth Cook mirror

5-secondary mirror 6-primary mirror

7-high-energy laser beam 8-reference mirror

9-internal focusing telescope 10-spectroscope

11-second detector 12-fixed focus lens

13-first detector

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise.

The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

The invention provides a high-power laser curde optical path debugging method, wherein a curde optical path is shown in fig. 1 (a), and comprises a first curde reflector 1, a second curde reflector 2, a third curde reflector 3, a fourth curde reflector 4, a main mirror 6 and

secondary mirrors

5 and 7 which are high-energy laser beams from an inlet to an outlet. Fig. 2 shows the position and rotation direction of the spindle, wherein the optical axis of the beam between the first and second kude-

mirror

1, 2 substantially coincides with the horizontal axis a of the turntable, and the optical axis of the beam exiting the fourth kude-mirror substantially coincides with the pitch axis B. The meaning of substantial coincidence is: the device has been roughly adjusted, the rotating shaft and the corresponding optical axis are coincident within the precision range of the roughly adjustment, but the fine adjustment with higher precision is still needed to make the variation of the spot position smaller. I.e. the final object of the invention is to achieve fine adjustment again by adjusting the position of the individual kude-mirrors with substantial coincidence.

The method specifically comprises the following steps:

step S1: the reference mirror 8 is installed at the entrance position of the kude optical path, so that the center cross of the reference mirror 8 coincides with the position of the high-power laser incidence axis, and the mirror surface of the reference mirror 8 is perpendicular to the optical axis of the high-power laser. "high power laser" refers to a laser having a power of not less than 10kW or a pulse energy of not less than 500J, according to the general definition in the art. The high power laser incidence axis refers to the optical axis of the incident laser light that enters the kude optical path and is reflected by the first kude mirror 1 in fig. 3.

Step S2: the beam splitter 10, the fixed focus lens 12 and the first detector 13 are sequentially arranged along an emergent light path, and the second detector 11 is arranged on a reflection light path of the beam splitter 10.

Step S3: the reference mirror 8 is aligned by the internal focusing telescope 9, the optical axis of the internal focusing telescope 9 is auto-collimated with the plane of the reference mirror 8, and the center coincides with the cross center of the reference mirror 8. After step S1 to step S3 are completed, the state shown in fig. 3 is an initial state before debugging.

Step S4: fixing the pitching axis of the turntable, rotating the horizontal axis, observing the cross position variation received by the first detector 13 and the second detector 11, and adjusting the first kude reflector 1 and the second kude reflector 2 to enable the cross position variation received by the first detector 13 and the second detector 11 to be respectively smaller than a first preset value and a second preset value when the horizontal axis of the turntable is rotated. The schematic diagram of this step is shown in fig. 4, namely, the device is changed from fig. 3 to fig. 4 by rotating the rotating shaft of the horizontal table. In one embodiment, the pixel sizes of the first detector 13 and the second detector 11 are 2.5 micrometers, and when the cross image received in the first detector 13 changes by 1 pixel along with the rotation of the turntable, the angle deviation between the optical axis of the high-energy laser and the rotating shaft is 25 micro radians; the cross image received in the second detector 11 changes its position by 1 pixel with one rotation of the turntable, indicating that the deviation between the optical axis of the high-energy laser and the position of the rotation axis is 2.5 micrometers. It should be noted that, the rotation of the horizontal axis means a complete rotation, that is, the rotation is still returned to the position shown in fig. 3 after the completion of the rotation, and the variation means the maximum value of the deviation in the process.

Step S5: fixing the horizontal axis of the turntable, rotating the pitching axis, observing the cross position variation received in the first detector 13 and the second detector 11, and adjusting the third kude reflector 3 and the fourth kude reflector 4 to enable the cross position variation received in the first detector 13 and the second detector 11 to be respectively smaller than a third preset value and a fourth preset value when the pitching axis of the turntable is rotated. The schematic diagram of this step is shown in fig. 5, i.e. the device is changed from fig. 3 to fig. 5 by rotating the pitch axis. Turning the pitch axis means turning a complete revolution, i.e. returning to the position shown in fig. 3 after the completion of the revolution, and the variation means the maximum value of the amount of deviation in the process.

The first preset value, the second preset value, the third preset value and the fourth preset value can be set to different values, and represent the precision requirements of different dimensions. The unit of the preset value may be a pixel. In a specific embodiment, the first preset value and the third preset value are 1 pixel, which represents that the spot position variation of the first detector 13 in the rotation process of two dimensions cannot be greater than 1 pixel, that is, the deviation of the angle between the optical axis of the high-energy laser and the rotating shaft needs to be less than 25 micro radians. The second preset value and the fourth preset value are 10 pixels, which represents that the spot position variation of the second detector 11 in the rotation process of two dimensions cannot be greater than 10 pixels, that is, the position deviation between the high-energy laser optical axis and the rotating shaft needs to be less than 25 micrometers.

Therefore, the method overcomes the defect that the traditional kude optical path cannot control the position change of the high-energy laser beam in the scanning process, and provides a high-precision debugging method based on the internal focusing telescope and the beam splitting probe lens group. Finally, the optical axis angle is not changed when the turntable rotates, and the position of the light beam is not changed.

While certain specific embodiments of the invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A high-power laser Curie light path debugging method, the stated Curie light path includes the first Curie mirror, second Curie mirror, third Curie mirror and fourth Curie mirror sequentially from entrance to exit;

characterized in that the method comprises:

the reference mirror is arranged at the entrance position of the kude optical path, so that the cross at the center of the reference mirror coincides with the position of the incident optical axis, and the mirror surface of the reference mirror is perpendicular to the optical axis of the high-power laser;

the beam splitter, the fixed focus lens and the first detector are sequentially arranged along an emergent light path, and the second detector is arranged on a reflection light path of the beam splitter;

aligning an inner focusing telescope with a reference mirror, wherein the optical axis of the inner focusing telescope is auto-collimated with the plane of the reference mirror, and the center of the inner focusing telescope coincides with the cross center of the reference mirror;

fixing a pitching axis of the turntable, rotating a horizontal axis, observing the cross position variation received by the first detector and the second detector, and enabling the cross position variation received by the first detector and the second detector to be respectively smaller than a first preset value and a second preset value when the horizontal axis of the turntable is rotated by adjusting the first kude reflector and the second kude reflector; the rotating horizontal shaft means rotating for a complete circle, namely returning to the initial position after the rotation is completed, and the variation is the maximum value of the deviation in the process;

fixing a horizontal axis of the turntable, rotating a pitching axis, observing the cross position variation received in the first detector and the second detector, and enabling the cross position variation received in the first detector and the second detector to be respectively smaller than a third preset value and a fourth preset value when the turntable pitching axis is rotated by adjusting a third kude reflector and a fourth kude reflector; the rotation pitch axis means a complete rotation, i.e., the rotation is completed and returned to the initial position, and the variation means the maximum value of the deviation amount in the process.

2. The method for adjusting the optical path of a high-power laser according to claim 1, wherein the focal length of the fixed focus lens is 100mm.

3. The method for debugging a high-power laser kude optical path according to claim 2, wherein,

the first preset value and the third preset value are 1 pixel, and the second preset value and the fourth preset value are 10 pixels.