CN112134135A

CN112134135A - Laser with automatic power optimization function

Info

Publication number: CN112134135A
Application number: CN202011217253.6A
Authority: CN
Inventors: 赵晓杰; 樊朴; 李硕; 苏炯锋; 黎凯; 林思引
Original assignee: Advanced Optowave Corp
Current assignee: Advanced Optowave Corp
Priority date: 2020-11-04
Filing date: 2020-11-04
Publication date: 2020-12-25

Abstract

The invention discloses a laser with automatic power optimization function, which comprises a closed resonant cavity and a control system, wherein a pumping source, a pumping mirror, a laser crystal, a Q switch, at least one nonlinear crystal and a cavity mirror for simultaneously reflecting double-frequency light and fundamental frequency light are arranged in the resonant cavity, the pumping mirror is used as one end mirror of the resonant cavity, the cavity mirror is used as the other end mirror of the resonant cavity, laser emitted by the pumping source sequentially passes through the pumping mirror, the laser crystal, the Q switch, the nonlinear crystal and the cavity mirror to be output, the laser crystal is used for absorbing the laser output by the pumping mirror to form laser oscillation between the two end mirrors, the laser further comprises a power detection feedback device, the power detection feedback device is electrically connected with the control system, and a beam expanding structure is arranged in the resonant cavity, the beam expanding structure is arranged on a laser output light path of the resonant cavity.

Description

Laser with automatic power optimization function

Technical Field

The invention relates to the technical field of lasers, in particular to a laser with an automatic power optimization function.

Background

With the progress of science and technology and the rapid development of laser technology, lasers have been widely used in the fields of communication, medical treatment, machining, weaponry, illumination, and the like.

The existing laser has several problems:

(1) the optical element can not bear overhigh power, and the coating film on the surface of the frequency doubling crystal is easy to damage.

(2) The output spot size is too small and easily damages the customer optical elements. The beam expander surface is also easily damaged by the addition of the beam expander.

(3) The existing laser resonant cavity is lack of an original element which can be used for adjusting a light path, and the deviation of an optical element generated in any transportation process, the power reduction and the light spot roundness reduction caused by the deviation cannot be recovered under the condition of not opening the cavity.

That is, as the service time of the laser goes on, the laser gradually degrades or even is damaged in the light emitting process, so that the output ultraviolet power is reduced or the laser cannot work normally.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a laser with an automatic power optimization function.

In order to achieve the purpose, the invention adopts the following technical scheme: a laser with an automatic power optimization function comprises a closed resonant cavity and a control system, wherein a pumping source, a pumping mirror, a laser crystal, a Q switch, at least one nonlinear crystal and a cavity mirror for simultaneously reflecting high frequency doubling light and fundamental frequency light are arranged in the resonant cavity, the pumping mirror is used as one end mirror of the resonant cavity, the cavity mirror is used as the other end mirror of the resonant cavity, laser emitted by the pumping source sequentially passes through the pumping mirror, the laser crystal, the Q switch, the nonlinear crystal and the cavity mirror to output, the laser crystal is used for absorbing the laser output by the pumping mirror to form laser oscillation between the two end mirrors, the laser further comprises a power detection feedback device, the power detection feedback device is electrically connected with the control system, a cavity mirror adjusting device is arranged in the resonant cavity, and the cavity mirror is arranged on the cavity mirror adjusting device, the cavity mirror adjusting device is used for adjusting a resonant light path in the resonant cavity, the cavity mirror adjusting device is electrically connected with the control system, and a beam expanding structure is arranged in the resonant cavity and arranged on a laser output light path of the resonant cavity.

The further technical scheme is as follows: the nonlinear crystal outputs at or near the brewster angle to fundamental frequency light.

The further technical scheme is as follows: the cavity mirror adjusting device comprises an adjusting mechanism and a driving assembly, the adjusting mechanism is connected with the driving assembly, the cavity mirror is fixedly arranged on the adjusting mechanism, the driving mechanism is electrically connected with a control system, and the adjusting mechanism is used for adjusting the angle of the cavity mirror so as to optimize the laser power output.

The further technical scheme is as follows: the power detection feedback device comprises a light splitting device and a light power measuring probe which are arranged on a laser output light path, the light power measuring probe is electrically connected with the control system, the light power measuring probe is used for receiving laser output by the light splitting device, and the control system is used for automatically optimizing the output power of the laser according to the power of the output laser.

The further technical scheme is as follows: the light splitting device is an ultraviolet optical polishing sheet without an optical film, and is placed in a range close to the Brewster angle with the output laser.

The further technical scheme is as follows: the beam expanding structure is a changeable point beam expander device, and the changeable point beam expander device is electrically connected with the control system.

The further technical scheme is as follows: the switchable point beam expander device comprises a motor, a rotating platform and a beam expander, wherein the beam expander is fixedly arranged on the rotating platform, the rotating platform is connected with an output shaft of the motor, the motor is electrically connected with the control system, and the motor is used for driving the rotating platform to rotate so as to adjust the position of laser on a first lens of the beam expander.

The further technical scheme is as follows: the beam expanding structure is a replaceable beam expander, and the replaceable beam expander is detachably connected with the resonant cavity.

The further technical scheme is as follows: an external switch is arranged behind the replaceable point beam expander device or the replaceable beam expander.

The further technical scheme is as follows: the air interchanger is arranged in the resonant cavity and comprises an air pump, a filter and a dryer, a drying agent is arranged in the dryer, an air inlet of the filter is connected with an air outlet of the air pump, and an air outlet of the filter is connected with an air inlet of the dryer.

Compared with the prior art, the invention has the beneficial effects that: the laser with the automatic power optimization function realizes power detection of light beams through the power detection feedback device. The resonant light path in the resonant cavity is adjusted through the cavity mirror adjusting device, so that the maximum output power of the whole laser with the automatic power optimization function is realized, and the power reduction caused by mechanical deformation due to transportation, vibration and the like is overcome. The beam expanding structure reduces power loss and influences the quality of the light beam, and the effect that maintenance can be facilitated in a production field without influencing use of a client is achieved.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above description and other objects, features, and advantages of the present invention more clearly understandable, preferred embodiments are described in detail below.

Drawings

FIG. 1 is a schematic diagram of a laser with automatic power optimization;

FIG. 2 is a schematic view of the structure of the cavity mirror adjusting device;

fig. 3 is a schematic diagram of a switchable point beam expander device.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and the detailed description.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be connected or detachably connected or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above should not be understood to necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by one skilled in the art.

As shown in fig. 1 to 3, a laser with an automatic power optimization function includes a closed resonant cavity 4 and a control system 5, a pumping source 41, a pumping mirror 42, a laser crystal 43, a Q-switch 44, at least one nonlinear crystal and a cavity mirror 47 for reflecting light of double frequency and fundamental frequency simultaneously and highly are disposed in the resonant cavity 4, the pumping mirror 42 is used as one end mirror of the resonant cavity 4, the cavity mirror 47 is used as the other end mirror of the resonant cavity 4, laser emitted from the pumping source 41 is sequentially output through the pumping mirror 42, the laser crystal 43, the Q-switch 44, the nonlinear crystal and the cavity mirror 47, the laser crystal 43 is used for absorbing laser output from the pumping mirror 42 to form laser oscillation between the two end mirrors, the laser further includes a power detection feedback device 7, the power detection feedback device 7 is electrically connected to the control system 5, a cavity mirror adjusting device 2 is disposed in the resonant cavity 4, the cavity mirror 47 is disposed on the cavity mirror adjusting device 2, the cavity mirror adjusting device 2 is used for adjusting a resonant light path in the resonant cavity 4, and the cavity mirror adjusting device 2 is electrically connected with the control system 5. The resonant cavity 4 is provided with a beam expanding structure, and the beam expanding structure is arranged on a laser output light path of the resonant cavity 4. Specifically, light emitted by the pump source 41 is absorbed by the laser crystal 43 through the pump mirror 42 to form laser oscillation, and fundamental frequency light generated by the laser oscillation is converted into double-frequency, triple-frequency or higher harmonic ultraviolet laser light by the nonlinear crystal after passing through the Q switch 44 to be output. The power detection feedback device 7 is used for detecting the power of the output laser beam, and the cavity mirror adjusting device 2 is used for adjusting a resonant light path in the resonant cavity 4, so that the whole laser with the automatic power optimization function can realize the maximum output power, and the power reduction caused by mechanical deformation due to transportation, vibration and the like is overcome. The beam expanding structure reduces power loss and influences the quality of the light beam, and the effect that maintenance can be facilitated in a production field without influencing use of a client is achieved.

In particular, the nonlinear crystal outputs at or near brewster angle to fundamental frequency light to prevent laser damage and to enable control of laser intensity.

Specifically, as shown in fig. 1, the nonlinear crystal includes a frequency doubling crystal 46 and a frequency tripling crystal 45, laser emitted from a pump source 41 is absorbed by a laser crystal 43 after passing through a pump mirror 42, laser oscillation is formed between the two end mirrors, and ultraviolet laser output is formed through the frequency tripling crystal 45 and the frequency doubling crystal 46.

Specifically, as shown in fig. 2, the cavity mirror 47 is an independent body, and if a slight change occurs in position, the resonant optical path of the laser deviates from an optimal state, which results in energy reduction of the laser output and deterioration of the beam quality. The cavity mirror adjusting device 2 comprises an adjusting mechanism 21 and a driving assembly 22, the adjusting mechanism 21 is connected with the driving assembly 22, a cavity mirror 47 is fixedly arranged on the adjusting mechanism 21, the driving assembly 22 is electrically connected with the control system 5, the driving assembly 22 comprises two driving motors which are a first driving motor 221 and a second driving motor 222 respectively, and the first driving motor 221 and the second driving motor 222 are used for adjusting the horizontal axis and the pitching axis of the cavity mirror 47 so as to optimize the laser power. When the power of the laser is reduced due to mechanical deformation caused by transportation, vibration and the like, the control system 5 transmits a detection signal sent by the power detection feedback device 7 to the driving assembly 22, and the driving assembly 22 drives the adjusting device to adjust the angle of the cavity mirror 47, so that the whole laser with the automatic optimization function realizes the maximum output power.

Specifically, as shown in fig. 1, the power detection feedback device 7 includes a light splitting device 71 and an optical power measuring probe 72, which are disposed on the laser output optical path, the optical power measuring probe 72 is electrically connected to the control system 5, the optical power measuring probe 72 is configured to receive the laser output by the light splitting device 71, and the control system 5 is configured to automatically optimize the output power of the laser according to the power of the output laser. The beam splitter 71 splits the laser beam output from the nonlinear crystal into two beams, one of which is output as a sub-energy (a small portion of laser light) that is power-detected by the optical power measuring probe 72 and transmits a detection signal to the control system 5.

Specifically, the beam splitting device 71 is an ultraviolet optical polishing sheet without an optical coating, thereby greatly prolonging the life of the crystal. The beam splitting device 71 is placed in a range close to the brewster angle with respect to the output laser light to prevent laser damage and to control the laser light intensity. The optical power measurement probe 72 may be a photodiode or the like.

Specifically, the ultraviolet optical polishing sheet is made of an ultraviolet optical material such as fused silica, CaF2 or MgF 2.

In another embodiment, the light splitting device 71 may be an uncoated flat mirror.

Specifically, as shown in fig. 1, the beam expanding structure is a switchable point beam expander device 3, and the switchable point beam expander device 3 is electrically connected to a control system 5. The point changing device 3 of the point-changeable beam expander can realize the automatic point changing of the beam expander, reduce the power loss and influence on the quality of light beams, and achieve the effect that the maintenance can be convenient and the use of customers can not be influenced in a production field.

Specifically, as shown in fig. 3, the switchable point beam expander device 3 includes a motor 11, a rotating platform 32 and a beam expander 33, the beam expander 33 is fixed on the rotating platform 32, the rotating platform 32 is connected to an output shaft of the motor 11, the motor 11 is electrically connected to the control system 5, and the motor 11 is used for driving the rotating platform 32 to rotate so as to adjust the position of the laser on the first lens of the beam expander 33. The laser is convenient to operate, manual debugging is omitted, efficiency is improved, and the energy of laser output by the laser is more stable.

In another embodiment, expand the removable expander that the beam structure was changed for convenience of customers, removable expander and 4 releasable connections of resonant cavity, removable expander on resonant cavity 4 is broken, can manually change from the resonant cavity 4 outsides, and convenient operation reduces power loss and the influence to the beam quality, reaches the effect of convenient maintenance. The effect that maintenance can be conveniently carried out on the production field without influencing the use of customers is achieved through the replaceable beam expander.

Specifically, as shown in fig. 1, an external shutter 8 is provided behind the exchangeable point expander device 3 or the exchangeable point expander. And the external switch 8 is automatically closed before the laser automatically optimizes the laser output power so as to prevent the output laser from damaging a workpiece or potential safety hazard.

Specifically, as shown in fig. 1, a ventilation device 6 is disposed in the resonant cavity 4, the ventilation device 6 includes an air pump 61, a filter 62 and a dryer 63, a drying agent is disposed in the dryer 63, an air inlet of the filter 62 is connected to an air outlet of the air pump 61, and an air outlet of the filter 62 is connected to an air inlet of the dryer 63. The ventilation device 6 is used for absorbing water vapor in the resonant cavity 4, reducing loss in the resonant cavity 4, stabilizing output energy of the laser and prolonging the service life of an optical device of the high-power laser.

Compared with the prior art, the laser with the automatic power optimization function provided by the invention can realize power detection on the light beam through the power detection feedback device. The resonant light path in the resonant cavity is adjusted through the cavity mirror adjusting device, so that the maximum output power of the whole laser with the automatic power optimization function is realized, and the power reduction caused by mechanical deformation due to transportation, vibration and the like is overcome. The beam expanding structure reduces power loss and influences the quality of the light beam, and the effect that maintenance can be facilitated in a production field without influencing use of a client is achieved.

The technical contents of the present invention are further illustrated by the examples only for the convenience of the reader, but the embodiments of the present invention are not limited thereto, and any technical extension or re-creation based on the present invention is protected by the present invention. The protection scope of the invention is subject to the claims.

Claims

1. A laser with an automatic power optimization function is characterized by comprising a closed resonant cavity and a control system, wherein a pumping source, a pumping mirror, a laser crystal, a Q switch, at least one nonlinear crystal and a cavity mirror for simultaneously reflecting double-frequency light and fundamental-frequency light are arranged in the resonant cavity, the pumping mirror is used as one end mirror of the resonant cavity, the cavity mirror is used as the other end mirror of the resonant cavity, laser emitted by the pumping source sequentially passes through the pumping mirror, the laser crystal, the Q switch, the nonlinear crystal and the cavity mirror to be output, the laser crystal is used for absorbing the laser output by the pumping mirror to form laser oscillation between the two end mirrors, the laser further comprises a power detection feedback device, the power detection feedback device is electrically connected with the control system, and a cavity mirror adjusting device is arranged in the resonant cavity, the cavity mirror is arranged on the cavity mirror adjusting device, the cavity mirror adjusting device is used for adjusting a resonant light path in the resonant cavity, the cavity mirror adjusting device is electrically connected with the control system, a beam expanding structure is arranged in the resonant cavity, and the beam expanding structure is arranged on a laser output light path of the resonant cavity.

2. The laser with automatic power optimization function of claim 1, wherein the nonlinear crystal is at or near brewster angle output for fundamental frequency light.

3. The laser with automatic power optimization function of claim 1, wherein the cavity mirror adjusting device comprises an adjusting mechanism and a driving assembly, the adjusting mechanism is connected with the driving assembly, the cavity mirror is fixedly arranged on the adjusting mechanism, the driving mechanism is electrically connected with a control system, and the adjusting mechanism is used for adjusting the angle of the cavity mirror to optimize the laser power output.

4. The laser with the automatic power optimization function according to claim 1, wherein the power detection feedback device includes a light splitting device and an optical power measuring probe, the light splitting device and the optical power measuring probe are disposed on a laser output light path, the optical power measuring probe is electrically connected to the control system, the optical power measuring probe is configured to receive the laser output by the light splitting device, and the control system is configured to automatically optimize the output power of the laser according to the power of the output laser.

5. The laser with automatic power optimization function of claim 4, wherein the light splitting device is an ultraviolet optical polishing sheet without an optical coating, and the light splitting device is placed in a range close to the Brewster angle with the output laser light.

6. The laser with automatic power optimization function of claim 1, wherein the beam expanding structure is a switchable point beam expander device, and the switchable point beam expander device is electrically connected with the control system.

7. The laser with automatic power optimization function of claim 6, wherein the switchable point beam expander device comprises a motor, a rotating platform and a beam expander, the beam expander is fixedly arranged on the rotating platform, the rotating platform is connected with an output shaft of the motor, the motor is electrically connected with the control system, and the motor is used for driving the rotating platform to rotate so as to adjust the position of the laser on the first lens of the beam expander.

8. The laser with automatic power optimization function of claim 1, wherein the beam expanding structure is a replaceable beam expander, and the replaceable beam expander is detachably connected with the resonant cavity.

9. The laser with automatic power optimization function of claim 7 or 8, wherein an external switch is arranged behind the switchable point beam expander device or the switchable point beam expander.

10. The laser with the automatic power optimization function according to any one of claims 1 to 8, wherein an air exchanging device is arranged in the resonant cavity, the air exchanging device comprises an air pump, a filter and a dryer, a drying agent is arranged in the dryer, an air inlet of the filter is connected with an air outlet of the air pump, and an air outlet of the filter is connected with an air inlet of the dryer.