CN116149069A

CN116149069A - Laser beam filtering system and laser beam shaping system

Info

Publication number: CN116149069A
Application number: CN202310428906.2A
Authority: CN
Inventors: 请求不公布姓名
Original assignee: Suzhou Gaoshi Semiconductor Technology Co ltd
Current assignee: Suzhou Gaoshi Semiconductor Technology Co ltd
Priority date: 2023-04-20
Filing date: 2023-04-20
Publication date: 2023-05-23
Anticipated expiration: 2043-04-20
Also published as: CN116149069B

Abstract

The present disclosure discloses a laser beam filtering system and a laser beam shaping system. The filtering system includes: the device comprises a wavelength adjusting first lens group, a caliber adjusting second lens group, a wavelength adjusting second lens group, a converging lens and a diaphragm which are sequentially arranged; the first lens group for adjusting the wavelength and the second lens group for adjusting the wavelength are positive focal power, and the first lens group for adjusting the caliber and the second lens group for adjusting the caliber are negative focal power; the laser beam filtering system is configured to: if the wavelength of the laser beam is changed, moving the first lens group for wavelength adjustment and the second lens group for wavelength adjustment; and if the caliber of the laser beam is changed, moving the caliber-adjusting first lens group and the caliber-adjusting second lens group. The filtering system is compatible with laser beams with different wavelengths or calibers in a targeted zooming mode, so that different laser beams can form equal-size focusing light spots at the same focusing position without changing a filtering device, and the adjustment efficiency of the laser beam filtering system is improved.

Description

Laser beam filtering system and laser beam shaping system

Technical Field

The present disclosure relates generally to the field of laser shaping technology. More particularly, the present disclosure relates to a laser beam filtering system and a laser beam shaping system.

Background

With the development of the semiconductor industry, the requirements on the detection precision of wafers and semiconductor chips are higher and higher, and the LED light source adopted by the traditional machine vision detection is gradually replaced by laser.

In order to solve the problem that the detection result is affected by uneven brightness in a formed light spot when laser beams are in Gaussian distribution, a current common mode is to use a filter device in a laser shaping light path, improve the quality of the laser beams through filtering, and reduce interference caused by stray light. The filtering device is usually a pinhole, and the pinhole is placed at the focusing position of the laser, so that the stray light can be filtered and most of energy can be passed at the same time. In order to ensure the filtering effect, the diameter of the pinhole is matched with the ideal Airy spot diameter of the focusing light spot. However, when the type of the laser is changed, such as the caliber or wavelength of the laser beam is changed, the ideal airy spot diameter of the focused light spot is also changed, and in order to adapt to the change, the filter device needs to be replaced and debugged.

Conventional zoom systems are capable of changing the aperture ratio of the collimation system, the application of which depends on two factors: firstly, in a certain wave band range, default that the focal length of all components in the wave band is unchanged, for example, the visible light generally adopts achromatic design in a wide wave band range; secondly, in the visible light band, the focal length of the optical element changes less with wavelength, so that the influence of the wavelength change can be ignored. However, for a laser system, for example, in the ultraviolet to visible light range, the refractive index of the optical material changes rapidly in the ultraviolet band, and the influence caused in the laser system is very large, especially for a filtering scene of small hole filtering, the influence cannot be directly ignored, and the change of wavelength can bring about the simultaneous change of collimation and caliber. Therefore, in the laser system, the conventional zoom system cannot simultaneously consider the change of the magnification caused by the wavelength change and the caliber change.

In addition, in the laser shaping process, in order to adapt to the change of the multiplying power, all components in the whole system need to be adjusted so as to ensure the zooming effect, and the debugging process is complex and has low efficiency.

In view of the foregoing, it is desirable to provide a laser beam filtering scheme that can improve the adjustment efficiency of a laser beam filtering system while achieving both wavelength variation and aperture variation-induced magnification variation.

Disclosure of Invention

To address at least one or more of the technical problems mentioned above, the present disclosure proposes laser beam filtering schemes in various aspects.

In a first aspect, the present disclosure provides a laser beam filtering system comprising: the device comprises a wavelength adjusting first lens group, a caliber adjusting second lens group, a wavelength adjusting second lens group, a converging lens and a diaphragm, which are sequentially arranged along the emergent direction of a laser; the first lens group for adjusting the wavelength and the second lens group for adjusting the wavelength are positive focal power, and the first lens group for adjusting the caliber and the second lens group for adjusting the caliber are negative focal power; the laser beam filtering system is configured to: if the wavelength of the laser beam is changed, moving the first lens group for wavelength adjustment and the second lens group for wavelength adjustment; and if the caliber of the laser beam is changed, moving the caliber-adjusting first lens group and the caliber-adjusting second lens group.

In some embodiments, moving the wavelength-adjusting first mirror group and the wavelength-adjusting second mirror group comprises: moving the first lens group for wavelength adjustment and the second lens group for wavelength adjustment until the first lens group for wavelength adjustment and the second lens group for wavelength adjustment meet

Wherein->

Indicating the wavelength of the laser beam, +.>

Indicating the amount of wavelength change of the laser beam; />

Represents the incident caliber of the laser beam on the converging lens, < ->

Representing the incident caliber variation of the laser beam on the converging lens; the moving aperture adjusting first lens group and the aperture adjusting second lens group include: moving the aperture-adjusting first lens group and/or the aperture-adjusting second lens group until +.>

。

In some embodiments, the movement functions of the wavelength-tuned first lens group and the wavelength-tuned second lens group are as follows:

the method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>

Indicating the distance of movement of the wavelength-adjusting first lens group, etc.>

Is positive indicating a movement towards the converging lens, +.>

For negative indication towards the laser, ">

Indicating the distance of movement of the wavelength-adjusting second mirror group, or +>

Is positive indicating a movement towards the converging lens, +.>

For negative indication towards the laser, ">

Represents the caliber of the laser beam emitted by the laser; the movement functions of the aperture adjustment first lens group and the aperture adjustment second lens group are as follows:

Indicating the moving distance of the aperture adjusting first lens group,

is positive indicating a movement towards the converging lens, +.>

For negative indication towards the laser, ">

Indicating caliber adjustmentThe moving distance of the second lens group, +.>

Is positive indicating a movement towards the converging lens, +.>

Being negative indicates a movement towards the laser,

the aperture variation of the laser beam emitted from the laser is shown.

In some embodiments, the movement function of the first lens group and the second lens group is adjusted at the wavelength

When the caliber of the laser beam is 1mm, if the wavelength of the laser beam is increased from 375nm to 457nm, the wavelength is adjusted by the moving distance of the first lens group>

Wavelength-adjusting the distance of movement of the second lens group +.>

The method comprises the steps of carrying out a first treatment on the surface of the When the caliber of the laser beam is 1mm, if the wavelength of the laser beam is increased from 375nm to 532nm, the wavelength is adjusted by the moving distance of the first lens group +.>

Wavelength-adjusting the moving distance of the second lens group

。

In some embodiments, the movement function of the aperture adjustment first lens group and the aperture adjustment second lens group

When the wavelength of the laser beam is 375nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group +.>

The moving distance of the aperture adjusting second lens group>

The method comprises the steps of carrying out a first treatment on the surface of the When the wavelength of the laser beam is 375nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 3mm, the caliber adjusts the moving distance of the first lens group +.>

The moving distance of the aperture adjusting second lens group>

The method comprises the steps of carrying out a first treatment on the surface of the When the wavelength of the laser beam is 457nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group +.>

The moving distance of the aperture adjusting second lens group>

The method comprises the steps of carrying out a first treatment on the surface of the When the wavelength of the laser beam is 457nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 3mm, the caliber adjusts the moving distance of the first lens group +.>

The moving distance of the aperture adjusting second lens group>

The method comprises the steps of carrying out a first treatment on the surface of the When the wavelength of the laser beam is 532nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group +.>

The moving distance of the aperture adjusting second lens group>

The method comprises the steps of carrying out a first treatment on the surface of the When the wavelength of the laser beam is 532nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 3mmAperture adjusting first lens group moving distance +.>

The moving distance of the aperture adjusting second lens group>

。/>

In some embodiments, the diaphragm is a pinhole having a diameter of

。

In some embodiments, the wavelength-tuning first mirror group is a biconvex lens with its first face facing the laser and its second face facing the aperture-tuning first mirror group; the wavelength adjusting second lens group is a meniscus positive lens, the first surface of the second lens group faces the caliber adjusting second lens group, and the second surface of the second lens group faces the converging lens; the aperture adjusting first lens group is a biconcave lens, the first surface of the biconcave lens faces the wavelength adjusting first lens group, and the second surface of the biconcave lens faces the aperture adjusting second lens group; the caliber-adjusting second lens group is a meniscus negative lens, the first surface of the caliber-adjusting second lens group faces the caliber-adjusting first lens group, and the second surface of the caliber-adjusting second lens group faces the wavelength-adjusting second lens group.

In some embodiments, the first face of the wavelength-adjusting first lens group has a radius of curvature of

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The radius of curvature of the first face of the aperture-adjusting first lens group is +.>

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The radius of curvature of the first face of the aperture-adjusting second lens group is +.>

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The radius of curvature of the first face of the wavelength-adjusting second lens group is +.>

The second face has a radius of curvature of +>

。

In a second aspect, the present disclosure provides a laser beam shaping system comprising: a laser beam filtering system, a collimation system, a laser shaper and a beam expanding and shrinking system as provided in any one of the first aspects; the laser beam filtering system, the collimation system, the laser shaper and the beam expanding and shrinking system are sequentially arranged along the emergent direction of the laser.

In some embodiments, the collimation system includes: a collimating concave lens and a collimating convex lens which are sequentially arranged along the emergent direction of the laser; the beam expanding and shrinking system comprises: the beam expanding and shrinking concave lens and the beam expanding and shrinking convex lens are sequentially arranged along the emergent direction of the laser.

Based on the laser beam filtering system provided above, the embodiments of the present disclosure provide two magnification-varying scenarios of wavelength-varying and aperture-varying in groups of wavelength-adjusting first mirror group, aperture-adjusting second mirror group, and wavelength-adjusting second mirror group. Moving the first lens group for wavelength adjustment and the second lens group for wavelength adjustment under a variable wavelength scene; and under the variable-caliber scene, the caliber-adjusting first lens group and the caliber-adjusting second lens group are moved, so that zooming is completed. The focusing lens has the advantages that the focusing lens is compatible with laser beams with different wavelengths or different calibers in a targeted zooming mode, so that different types of laser beams can form Airy spots with the same size at the same focusing position after passing through the focusing lens, and a filter device does not need to be frequently replaced and debugged, the adjusting efficiency of a laser beam filter system is improved, modularization and batch optical path debugging products are facilitated, and the cost is saved.

Drawings

The above, as well as additional purposes, features, and advantages of exemplary embodiments of the present disclosure will become readily apparent from the following detailed description when read in conjunction with the accompanying drawings. Several embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar or corresponding parts and in which:

FIG. 1 illustrates an exemplary block diagram of a laser beam filtering system of some embodiments of the present disclosure;

FIG. 2 illustrates an example diagram of a debugging process of a laser beam filtering system of some embodiments of the present disclosure;

FIG. 3 illustrates an example diagram of a debugging process of a laser beam filtering system of other embodiments of the present disclosure;

FIG. 4 illustrates a point plot of a focused spot of a laser beam filtering system of some embodiments of the present disclosure;

fig. 5 illustrates an exemplary block diagram of a laser beam shaping system of some embodiments of the present disclosure.

Detailed Description

The following description of the embodiments of the present disclosure will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the disclosure. Based on the embodiments in this disclosure, all other embodiments that may be made by those skilled in the art without the inventive effort are within the scope of the present disclosure.

It should be understood that the terms "comprises" and "comprising," when used in this specification and the claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the present disclosure is for the purpose of describing particular embodiments only, and is not intended to be limiting of the disclosure. As used in the specification and claims of this disclosure, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that the term "and/or" as used in the present disclosure and claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

As used in this specification and the claims, the term "if" may be interpreted as "when..once" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if a determination" or "if a [ described condition or event ] is detected" may be interpreted in the context of meaning "upon determination" or "in response to determination" or "upon detection of a [ described condition or event ]" or "in response to detection of a [ described condition or event ]".

Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

Exemplary application scenarios

In order to improve the quality of a light source for visual detection, the existing laser shaping light path can filter a laser beam by adopting a filter device so as to improve the quality of the laser beam and reduce interference tradition caused by stray light. The current common filtering device is provided with a pinhole, the pinhole needs to be placed at a laser focusing position in order to ensure the filtering effect, and the diameter of the pinhole is matched with the ideal Airy spot diameter of a focusing light spot formed by a laser beam.

However, the types of lasers on the market are different, the caliber and wavelength of the emitted laser beams are different, so that the ideal Airy spot diameter is changed, and a set of fixed laser shaping system is difficult to match with various lasers, so that with the switching of the lasers, a filter device in the laser shaping system is also required to be replaced and debugged frequently correspondingly.

In order to solve the above problems, the prior art adopts a conventional zoom system in a laser shaping system to adjust the aperture ratio of a collimation system. However, the conventional zoom system changes only the focal length or changes only the magnification, which does not take into consideration the focal length change caused by the wavelength change, and thus it is applicable to only a single wavelength system or a broadband system.

In addition, in order to adapt to the magnification change, in the debugging process, a plurality of components in the laser shaping system need to be adjusted in a linkage mode to ensure the magnification change effect, and the debugging complexity is high and the efficiency is low.

Exemplary laser Beam Filtering scheme

In view of this, the embodiments of the present disclosure provide a laser beam filtering scheme, which groups two magnification changing scenes of variable wavelength and variable aperture by a wavelength adjusting first lens group, an aperture adjusting second lens group and a wavelength adjusting second lens group, so as to implement a targeted zoom scheme, thereby being capable of forming an airy spot of the same size at the same focusing position without frequent replacement and debugging of the filtering device.

Fig. 1 illustrates an exemplary block diagram of a laser beam filtering system in accordance with some embodiments of the present disclosure.

As shown in fig. 1, the present disclosure provides a laser beam filtering system 10 comprising: the lens comprises a wavelength adjusting first lens group 11, a caliber adjusting first lens group 12, a caliber adjusting second lens group 13, a wavelength adjusting second lens group 14, a converging lens 15 and a diaphragm 16.

The wavelength adjusting first lens group 11, the caliber adjusting first lens group 12, the caliber adjusting second lens group 13, the wavelength adjusting second lens group 14, the converging lens 15 and the diaphragm 16 are sequentially arranged along the emergent direction of the laser, wherein the wavelength adjusting first lens group 11 and the wavelength adjusting second lens group 14 are positive focal power, the caliber adjusting first lens group 12 and the caliber adjusting second lens group 13 are negative focal power, and the converging lens 15 is positive focal power.

The laser beam generated by the laser sequentially passes through the first lens group 11 for wavelength adjustment, the first lens group 12 for aperture adjustment, the second lens group 13 for aperture adjustment and the second lens group 14 for wavelength adjustment, is collimated and expanded, then enters the converging lens 15, is converged into a focus through the converging lens 15, and the diaphragm 16 is arranged at the focus for filtering the laser beam.

A diaphragm refers to an entity in an optical system that acts to limit a light beam, which may be an edge of a lens, a frame, or a specially configured perforated screen, the effect of which includes limiting the light beam or limiting the field of view size. Further, the diaphragm 16 may be a pinhole.

The wavelength adjustment first lens group 11 may be a positive power lens group formed of a plurality of lenses, or may be a single convex lens. Similarly, the wavelength-adjusting second lens group 14 may be a positive power lens group composed of a plurality of lenses, or may be a single-piece convex lens; the aperture-adjusting first lens group 12 and/or the aperture-adjusting second lens group 13 may be a negative power lens group formed by a plurality of lenses, or may be a single concave lens.

Fig. 2 illustrates an example diagram of a debugging process of a laser beam filtering system of some embodiments of the present disclosure. As shown in fig. 2, the laser beam filtering system 10 in the embodiment of the disclosure may be adapted for both laser beam aperture variation and laser beam wavelength variation, and in particular, the laser beam filtering system 10 is configured to:

if the wavelength of the laser beam changes, moving the wavelength adjusting first mirror group 11 and the wavelength adjusting second mirror group 14;

if the aperture of the laser beam is changed, the aperture adjustment first lens group 12 and the aperture adjustment second lens group 13 are moved.

In the above adjustment process, the positions of the converging lens 15 and the diaphragm 16 are not adjusted, and the diaphragm 16 does not need to be replaced.

The calculation formula of the airy disk radius is as follows:

wherein->

Indicate wavelength, & lt + & gt>

Representing the aperture of the diffraction screen. For machine vision inspection, the aperture of the diffraction screen can also be understood as the aperture transmittance diameter; in the laser beam filtering system 10, the laser beam is collimated and expanded and then is incident on the converging lens 15 to form a focusing spot, and at this time, the diameter of the aperture transmission can be understoodThe aperture of the laser beam incident on the condensing lens 15, that is, the aperture of the laser beam emitted from the wavelength adjustment second mirror group 14.

That is, in the laser beam filtering system 10 provided by the present disclosure, the ideal airy spot radius of the focused spot

Wherein->

The aperture of incidence of the laser beam on the condensing lens 15 is shown.

When the wavelength of the laser beam emitted by the laser

When the change occurs, it is assumed that the wavelength is defined by +.>

Become->

In order to ensure that the ideal airy spot radius of the focused spot is unchanged, the wavelength-adjusting first mirror group 11 and the wavelength-adjusting second mirror group 14 are moved such that +.>

Wherein->

Indicating the wavelength variation of the laser beam, +.>

The variation of the incident aperture of the laser beam on the condensing lens 15 is shown.

It can be understood that by moving the first wavelength adjusting mirror group 11 and the second wavelength adjusting mirror group 14 in the laser beam filtering system 10, the variation trend of the emergent caliber of the laser beam emitted by the second wavelength adjusting mirror group 14 is consistent with the variation trend of the wavelength of the laser beam, i.e. the ratio of the emergent caliber of the second wavelength adjusting mirror group 14 to the wavelength of the laser beam is increased by 42%, so that the ratio of the emergent caliber of the second wavelength adjusting mirror group to the wavelength of the laser beam is unchanged, and the ideal airy focal radius of the focusing light spot is ensured to be unchanged.

For ease of understanding, the scene of laser wavelength variation is further described herein with reference to magnification.

Used herein

、/>

、/>

、/>

The optical power of the first lens group 11 for wavelength adjustment, the first lens group 12 for aperture adjustment, the second lens group 13 for aperture adjustment, and the second lens group 14 for wavelength adjustment are sequentially represented, and the optical power of the combination of the first lens group 11 for wavelength adjustment and the first lens group 12 for aperture adjustment is represented>

Optical power of combination of aperture-adjusting second lens group 13 and wavelength-adjusting second lens group 14 +.>

Wherein->

Indicating the distance between the first lens group 11 for wavelength adjustment and the first lens group 12 for aperture adjustment, +.>

The distance between the aperture-adjusting second lens group 13 and the wavelength-adjusting second lens group 14 is shown.

For a certain laser wavelength

A corresponding magnification +.>

When (when)Wavelength->

When the change occurs, the person is added with->

And->

Is also correspondingly changed, resulting in->

A change occurs.

And can be adjusted by moving the wavelength-adjusting first mirror group 11 and the wavelength-adjusting second mirror group 14

And->

Thereby adjusting +.>

And->

The magnification can be adjusted by the partial sub-items in the system, so that the emergent light caliber under the magnification of the final system can meet the requirement of unchanged Airy spot radius.

When the caliber of the laser beam emitted by the laser is changed, the wavelength is not changed at the moment, and the ideal Airy spot radius of the focusing light spot is used for adjusting the focal length

It can be known that the incident aperture of the converging lens is maintained unchanged, so that the ideal Airy spot radius of the focused light spot is ensured to be unchanged, and at the moment, the aperture adjustment first lens group 12 and the aperture adjustment second lens group 13 are moved to enable ∈>

。

It can be understood that by moving the aperture adjusting first lens group 12 and the aperture adjusting second lens group 13 in the laser beam filtering system 10, laser beams with the same wavelength and different apertures can be made to enter the converging lens 15 with the same incident aperture, so that the ratio of the wavelength to the incident aperture of the converging lens is unchanged, and the ideal airy spot radius of the focused light spot is ensured to be unchanged.

Because there is a matching requirement between the size of the diaphragm 16 and the ideal airy spot diameter of the focused light spot formed by the laser beam, the same filtering effect can be achieved without replacing the diaphragm 16 with another size on the premise of ensuring that the ideal airy spot radius of the focused light spot is unchanged.

It can be appreciated that the laser beam filtering system in the embodiments of the present disclosure can achieve the following two laser beam adjustment effects:

firstly, laser beams with the same caliber but different wavelengths are emitted into collimated laser beams with different calibers after passing through a first lens group 11 for adjusting the wavelength, a first lens group 12 for adjusting the caliber, a second lens group 13 for adjusting the caliber and a second lens group 14 for adjusting the wavelength, wherein the changing proportion of the calibers of the laser beams is consistent with the changing proportion of the wavelengths;

and secondly, the laser beams with the same wavelength and different calibers are emitted into collimated laser beams with the same caliber after passing through the first lens group 11 for wavelength adjustment, the first lens group 12 for caliber adjustment, the second lens group 13 for caliber adjustment and the second lens group 14 for wavelength adjustment.

In the adjustment process, the wavelength adjustment first lens group 11 and the wavelength adjustment second lens group 14 have positive focal power, and both the two lens groups have the same converging effect on the laser beams, and the effects are similar; the aperture-adjusting first lens group 12 and the aperture-adjusting second lens group 13 are of negative focal power, and both the aperture-adjusting first lens group and the aperture-adjusting second lens group have the same divergence effect on the laser beam and similar effects. Therefore, the wavelength adjusting first lens group 11 and the wavelength adjusting second lens group 14 are divided into one group for adapting to the situation of changing the wavelength of the laser beam, while the caliber adjusting first lens group 12 and the caliber adjusting second lens group 13 are divided into the other group for adapting to the situation of changing the caliber of the laser beam, so that the component types in the two debugging processes are reduced, the debugging structure is simplified, and the debugging complexity is reduced.

According to the focusing lens, the targeted zooming mode is compatible with laser beams with different wavelengths or different calibers, so that after the laser beams with different types pass through the focusing lens, the Airy spots with the same size can be formed at the same focusing position, the filter device does not need to be replaced and debugged frequently, and the adjustment efficiency of the laser beam filter system is improved.

The change of multiplying power caused by wavelength and/or caliber of the laser beam is not in linear relation with the moving distance of the lens group in the debugging process, so that the embodiment adopts a hidden function form to respectively represent the moving functions of the lens group in the wavelength and caliber changing process.

Fig. 3 illustrates an example diagram of a debugging process of a laser beam filtering system of other embodiments of the present disclosure. The following describes a specific implementation procedure of the above-described movement function with reference to fig. 3.

First, a scene of a laser beam wavelength change will be described.

The movement functions of the wavelength-adjusting first mirror group 11 and the wavelength-adjusting second mirror group 14 can be expressed as follows:

；

wherein,

Is positive indicating a movement towards the converging lens, +.>

Negative indicates movement toward the laser;

Is positive to represent toward convergenceThe lens is moved so that the lens is moved,

negative indicates movement toward the laser;

the aperture of the laser beam emitted from the laser is shown.

For easy understanding, the caliber of the laser beam is used as follows

For example, a case of 1mm will be described as a function of movement of the lens group when changing the wavelength.

If the wavelength of the laser beam is changed from 375nm to 457nm

，/>

That is, the wavelength-adjusting first lens group 11 is moved toward the condensing lens 15 by 4.001mm, and the wavelength-adjusting second lens group 14 is moved toward the condensing lens 15 by 3.474mm. At this time, the incident aperture of the condensing lens 15>

Changing from 3mm to 3.68mm.

If the wavelength of the laser beam is changed from 375nm to 532nm

，/>

I.e. the wavelength-adjusting first mirror group 11 is moved 7.881mm towards the converging lens 15 and the wavelength-adjusting second mirror group 14 is moved 5.384mm towards the converging lens 15. At this time, the incident aperture of the condensing lens 15>

Changing from 3mm to 4.29mm.

Next, a scene in which the caliber of the laser beam changes will be described.

The movement functions of the aperture adjustment first lens group 12 and the aperture adjustment second lens group 13 can be expressed as follows:

；

wherein,

indicating the movement distance of the aperture-adjusting first lens group, < >>

Is positive indicating a movement towards the converging lens, +.>

Negative indicates movement toward the laser;

indicating the movement distance of the aperture-adjusting second lens group, < >>

Is positive to indicate movement towards the converging lens,

negative indicates movement toward the laser;

the aperture variation of the laser beam emitted from the laser is shown.

For ease of understanding, the movement function of the lens group at the time of changing the aperture will be described below.

In the first case, it is assumed that the laser beam wavelength of the laser is fixed to 375nm.

If the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm

，/>

That is, the aperture adjustment first lens group 12 moves 9.7mm toward the converging lens 15, and the aperture adjustment second lens group 13 moves 0.335mm toward the converging lens 15; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 3mm.

If the caliber of the laser beam emitted by the laser is increased from 1mm to 3mm

，/>

I.e. aperture adjusting first lens group 12 moves 13.389mm towards converging lens 15 and aperture adjusting second lens group 13 moves 1.409mm towards converging lens 15; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 3mm. />

In the second case, it is assumed that the laser beam wavelength of the laser is fixed at 457nm.

，/>

I.e. aperture adjusting first mirror group 12 moves 11.582mm towards converging lens 15 and aperture adjusting second mirror group 13 moves 0.149mm towards the laser; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 3.68mm.

，/>

I.e. aperture adjusting first lens group 12 moves 16.123mm towards converging lens 15 and aperture adjusting second lens group 13 moves 0.606mm towards converging lens 15; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 3.68mm.

In the third case, it is assumed that the laser beam wavelength of the laser is fixed at 532nm.

，/>

I.e. aperture-adjusting first mirror group 12 moves 13.165mm towards converging lens 15 and aperture-adjusting second mirror group 13 moves 0.552mm towards the laser; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 4.29mm.

，/>

I.e. the aperture-adjusting first lens group 12 is moved 18.45mm towards the converging lens 15 and the aperture-adjusting second lens group 13 is moved 0.079mm towards the laser; after adjustment, the entrance aperture of the converging lens 15 is +.>

Still 4.29mm.

Combining the above-mentioned several cases of laser beam wavelength and caliber variation, nine parameter examples of the laser beam filtering system can be found as shown in the following table:

wherein,

indicating the spacing of the laser from the wavelength-adjusting first mirror group 11,/for example>

Represents the distance between the aperture-adjusting first lens group 12 and the aperture-adjusting second lens group 13, +.>

Represents the distance between the aperture-adjusting second lens group 13 and the wavelength-adjusting second lens group 14, +.>

Representing the spacing of the wavelength-adjusting second lens group 14 from the converging lens 15.

According to the above table, in the above nine parameter examples, the distances from the laser to the converging lens 15 are uniform and are 233.92mm, that is, the positions of the laser and the converging lens 15 are fixed and do not move during the adjustment process.

It should be noted that, the wavelength adjusting first lens group 11 is a biconvex lens, a first surface faces the laser, and a second surface faces the aperture adjusting first lens group;

the wavelength adjusting second lens group 14 is a meniscus positive lens, a first surface of the second lens group faces the aperture adjusting second lens group, and a second surface of the second lens group faces the converging lens;

the aperture-adjusting first lens group 12 is a biconcave lens, a first surface of which faces the wavelength-adjusting first lens group, and a second surface of which faces the aperture-adjusting second lens group;

the aperture-adjusting second lens group 13 is a meniscus negative lens, a first surface of the second lens group faces the aperture-adjusting first lens group, and a second surface of the second lens group faces the wavelength-adjusting second lens group;

the converging lens is a biconvex lens, the first surface of the converging lens faces the wavelength adjusting second lens group, and the second surface of the converging lens faces the diaphragm.

Wherein the curvature radius of the first surface of the wavelength adjusting first lens group 11 is as follows

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the Optionally, the radius of curvature of the first face of the wavelength-adjusting first mirror group 11 is 80.234mm and the radius of curvature of the second face is-43.442 mm.

The thickness of the wavelength-adjusting first lens group 11 may be

Alternatively, the thickness of the wavelength-adjusting first mirror group 11 is 5mm.

In some embodiments, the wavelength-adjusting first lens group 11 may employ an optical glass of the model f_silca.

The radius of curvature of the first surface of the aperture-adjusting first lens group 12 is

The curvature radius of the second surface is

The method comprises the steps of carrying out a first treatment on the surface of the Optionally, the radius of curvature of the first face of the aperture-adjusting first lens group 12 is-15.001 mm and the radius of curvature of the second face is 15.035mm.

The thickness of the aperture-adjusting first lens group 12 can be

Optionally, the aperture adjusts the thickness of the first lens group 12 to 3mm.

In some embodiments, aperture-adjusting first lens group 12 may employ optical glass of type F_SILICA.

The radius of curvature of the first surface of the aperture-adjusting second lens group 13 is

First, theRadius of curvature of two faces

The method comprises the steps of carrying out a first treatment on the surface of the Alternatively, the radius of curvature of the first face of the aperture-adjusting second mirror group 13 is 324.897mm, and the radius of curvature of the second face is 15.000mm.

The thickness of the aperture-adjusting second lens group 13 can be

Alternatively, the thickness of the aperture-adjusting second mirror group 13 is 3mm.

In some embodiments, the aperture-adjusting second lens group 13 may employ an optical glass of the model f_silca.

The radius of curvature of the first face of the wavelength-adjusting second lens group 14 is

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the Optionally, the radius of curvature of the first face of the wavelength-tuned second lens group 14 is-948.432 mm and the radius of curvature of the second face is-74.904 mm.

The thickness of the wavelength-adjusting second lens group 14 may be

Optionally, the wavelength-adjusting second mirror group 14 has a thickness of 5mm.

In some embodiments, the wavelength-modifying second lens group 14 may employ optical glass, model N-LASF 31.

The radius of curvature of the first surface of the converging lens 15 is

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the Alternatively, the radius of curvature of the first face of the converging lens 15 is 86.679mm and the radius of curvature of the second face is-384.385 mm.

The thickness of the converging lens 15 may beIs that

Alternatively, the thickness of the converging lens 15 is 5mm.

In some embodiments, the converging lens 15 may employ optical glass of type F_SILICA.

The distance between the diaphragm 16 and the converging lens 15 is

(II), (III), (V), (; optionally, the diaphragm 16 is arranged at a distance 149.755mm from the converging lens 15.

Fig. 4 illustrates a spot diagram of a focused spot of a laser beam filtering system in accordance with some embodiments of the present disclosure. The spot diagram of the focused spot shown in fig. 4 corresponds to nine parameter examples of the laser beam filtering system shown in the table above.

As shown in the three dot-matrix diagrams shown in the leftmost column in fig. 4, by moving the positions of the first lens group for wavelength adjustment and the second lens group for wavelength adjustment, laser beams with different wavelengths can form focusing light spots with the same size at the same focusing position, and the airy radius of the focusing light spots is as follows

。

Similarly, as shown in the three dot-matrix diagrams in the first row in fig. 4, by moving the positions of the aperture adjustment first lens group and the aperture adjustment second lens group, laser beams with different apertures can form a focusing light spot with the same size at the same focusing position, and the airy focal radius of the focusing light spot is 23.12 μm.

Further, the aperture 16 in the laser beam filtering system 10 is a pinhole, and after the converging lens 15 focuses the laser beam into a focal point, the pinhole is placed at the focal point, so that it is ensured that most of energy passes through while stray light is filtered. The diameter of the pinhole needs to be precisely matched with the laser beam filtering system, too small pinhole will cause too much laser energy loss, too large pinhole will not achieve the filtering effect, and in order to ensure the filtering effect, the diameter of the pinhole should be in the range of 0.5 to 1.5 of the ideal Airy spot diameter of the focused light spot, therefore, the pinholeIs of the diameter of

。

The above describes an alternative range of pinhole diameters, which in practice are not adjusted once they are fixed, and in practice may be fixed by, for example, 0.8× the ideal airy diameter, for example, a pinhole with a diameter of 18.5 μm.

Based on the laser beam filtering system provided by any of the foregoing embodiments, the present disclosure further provides a laser beam shaping system, and fig. 5 shows an exemplary block diagram of the laser beam shaping system of some embodiments of the present disclosure.

As shown in fig. 5, the laser beam shaping system provided in this embodiment includes: the laser beam filtering system 10, the collimating system 20, the laser shaper 30 and the beam expanding and shrinking system 40 are sequentially arranged along the outgoing direction of the laser 60.

The laser beam filtering system 10 has been described in detail in the previous embodiments, and will not be described in detail herein.

The collimating system 20 comprises a collimating concave lens and a collimating convex lens arranged in sequence along the exit direction of the laser. As shown in fig. 5, the laser beam filtered by the diaphragm 16 is divergent and collimated into a parallel beam by the collimating system 20.

The laser shaper 30 is a type of diffractive optical element (DOE, diffractive Optical Elements) that modulates the beam wavefront by microstructure, converting a gaussian distributed incident laser beam into a uniform intensity or arbitrary intensity distribution spot in the shape of a line, rectangle, square, and circle.

The laser shaper 30 is capable of converting a parallel light beam formed by the collimating system 20 into a spot of a specified shape and intensity distribution.

The beam expanding and shrinking system 40 includes an expanding and shrinking concave lens and an expanding and shrinking convex lens, which are sequentially arranged along the outgoing direction of the laser, and are used for expanding or shrinking the size of the laser beam outgoing from the laser shaper 30.

Further, if the light spot is required to be a linear light spot, a cylindrical mirror 50 may also be provided in the laser beam shaping system. The cylindrical mirror 50 is disposed in the laser emitting direction of the beam expanding and shrinking system 40, the cylindrical mirror 50 has positive focal power, and after the laser beams emitted from the beam expanding and shrinking system 40 are converged by the cylindrical mirror 50, uniform laser beam spots are formed at the focal point.

It should be noted that, the collimation system 20, the laser shaper 30, the beam expanding and shrinking system 40 and the cylindrical mirror 50 in the laser beam shaping system are optional modules, and in the practical application process, the modules in the system can be added, deleted or modified according to practical requirements, so as to generate laser beams with different shapes or sizes.

Further, the laser beam shaping system may further include a driving system and a control system, where the driving system is connected to the laser beam filtering system 10, the collimating system 20, the laser shaper 30, the beam expanding and shrinking system 40, and the cylindrical mirror 50, respectively, and the driving system may move any one or more of the laser beam filtering system 10, the collimating system 20, the laser shaper 30, the beam expanding and shrinking system 40, and the cylindrical mirror 50 under the control of the control system. Further, under the control of the control system, the driving system can drive the wavelength adjusting first lens group 11, the caliber adjusting first lens group 12, the caliber adjusting second lens group 13 and the wavelength adjusting second lens group 14 in the laser beam filtering system 10 to move, so that the debugging of the laser beam filtering system 10 is completed, and the consistency of the Airy spot radius of the focusing light spot formed by the laser beam after passing through the converging lens 15 is ensured.

While various embodiments of the present disclosure have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous modifications, changes, and substitutions will occur to those skilled in the art without departing from the spirit and scope of the present disclosure. It should be understood that various alternatives to the embodiments of the disclosure described herein may be employed in practicing the disclosure. The appended claims are intended to define the scope of the disclosure and are therefore to cover all equivalents or alternatives falling within the scope of these claims.

Claims

1. A laser beam filtering system, comprising: the device comprises a wavelength adjusting first lens group, a caliber adjusting second lens group, a wavelength adjusting second lens group, a converging lens and a diaphragm, which are sequentially arranged along the emergent direction of a laser;

the first lens group for adjusting the wavelength and the second lens group for adjusting the wavelength are positive focal power, and the first lens group for adjusting the caliber and the second lens group for adjusting the caliber are negative focal power;

the laser beam filtering system is configured to:

if the wavelength of the laser beam is changed, moving the first lens group for wavelength adjustment and the second lens group for wavelength adjustment;

and if the caliber of the laser beam is changed, moving the caliber adjusting first lens group and the caliber adjusting second lens group.

2. The laser beam filtering system of claim 1, wherein,

said moving said wavelength-adjusting first mirror group and said wavelength-adjusting second mirror group, comprising:

moving the first lens group and the second lens group until the wavelength adjustment is satisfied

Wherein, the method comprises the steps of, wherein,

indicating the wavelength of the laser beam, +.>

Indicating the amount of wavelength change of the laser beam; />

Represents the incident aperture of the laser beam on the converging lens, < >>

Representing the incident caliber variation of the laser beam on the converging lens;

the moving the aperture adjustment first lens group and the aperture adjustment second lens group includes:

moving the caliber adjusting first lens group and/or the caliber adjusting second lens group until the caliber adjusting first lens group and/or the caliber adjusting second lens group meet the requirements

。

3. The laser beam filtering system of claim 2, wherein,

the movement functions of the wavelength adjusting first lens group and the wavelength adjusting second lens group are as follows:

；

wherein,

Is positive to indicate movement towards the converging lens,

for negative indication towards the laser, ">

Is positive indicating a movement towards the converging lens, +.>

For negative indication towards the laser, ">

Represents the caliber of the laser beam emitted by the laser;

the movement functions of the caliber adjusting first lens group and the caliber adjusting second lens group are as follows:

；

wherein,

Is positive to indicate movement towards the converging lens,

for negative indication towards the laser, ">

Is positive indicating a movement towards the converging lens, +.>

For negative indication towards the laser, ">

The aperture variation of the laser beam emitted from the laser is shown.

4. A laser beam filter system as claimed in claim 3, wherein,

a movement function between the wavelength-adjusting first lens group and the wavelength-adjusting second lens group

In the process,

when the caliber of the laser beam is 1mm, if the wavelength of the laser beam is increased from 375nm to 457nm, the wavelength adjusts the moving distance of the first lens group

The wavelength adjusts the moving distance of the second lens group

；

When the caliber of the laser beam is 1mm, if the wavelength of the laser beam is increased from 375nm to 532nm, the wavelength adjusts the moving distance of the first lens group

The wavelength adjusts the moving distance of the second lens group +.>

。

5. A laser beam filter system as claimed in claim 3, wherein,

a movement function between the aperture adjustment first lens group and the aperture adjustment second lens group

In the process,

when the wavelength of the laser beam is 375nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group

The caliber adjusts the moving distance of the second lens group

；

When the wavelength of the laser beam is 375nm, if the laser beam is excitedThe caliber of the laser beam emitted by the optical device is increased from 1mm to 3mm, and then the caliber adjusts the moving distance of the first lens group

The aperture adjusting distance of the second lens group>

；

When the wavelength of the laser beam is 457nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group

The aperture adjusting distance of the second lens group>

；

When the wavelength of the laser beam is 457nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 3mm, the caliber adjusts the moving distance of the first lens group

The aperture adjusting distance of the second lens group>

；

When the wavelength of the laser beam is 532nm, if the caliber of the laser beam emitted by the laser is increased from 1mm to 2mm, the caliber adjusts the moving distance of the first lens group

The aperture adjusting distance of the second lens group>

；

When the wavelength of the laser beam is 532nm, the caliber of the laser beam emitted by the laser is increased from 1mmWhen the aperture is increased to 3mm, the aperture adjusts the moving distance of the first lens group

The caliber adjusts the moving distance of the second lens group

。

6. The laser beam filtering system of claim 4 or 5, wherein,

the diaphragm is a pinhole with a diameter of

。

7. The laser beam filtering system of claim 1, wherein,

the first lens group for wavelength adjustment is a biconvex lens, the first surface of the first lens group faces the laser, and the second surface of the first lens group faces the caliber adjustment;

the second lens group with wavelength adjustment is a meniscus positive lens, a first surface of the second lens group faces the caliber adjusting second lens group, and a second surface of the second lens group faces the converging lens;

the caliber-adjusting first lens group is a biconcave lens, a first surface of the biconcave lens faces the wavelength-adjusting first lens group, and a second surface of the biconcave lens faces the caliber-adjusting second lens group;

the caliber-adjusting second lens group is a meniscus negative lens, the first surface of the caliber-adjusting second lens group faces the caliber-adjusting first lens group, and the second surface of the caliber-adjusting second lens group faces the wavelength-adjusting second lens group.

8. The laser beam filtering system of claim 7, wherein,

the curvature radius of the first surface of the first lens group is adjusted to be

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the wavelength-adjusting first lens group is +.>

；

The radius of curvature of the first surface of the caliber-adjusting first lens group is as follows

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the caliber-adjusting first lens group is +.>

；

The radius of curvature of the first surface of the caliber-adjusting second lens group is as follows

The curvature radius of the second surface is

The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the caliber-adjusting second lens group is +.>

；

The curvature radius of the first surface of the wavelength adjusting second lens group is as follows

The second face has a radius of curvature of +>

The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the wavelength-adjusting second lens group is +.>

。

9. A laser beam shaping system, comprising: the laser beam filtering system, collimation system, laser shaper and beam expanding and shrinking system of any one of claims 1-8;

the laser beam filtering system, the collimation system, the laser shaper and the beam expanding and shrinking system are sequentially arranged along the outgoing direction of the laser.

10. The laser beam shaping system according to claim 9, wherein,

the collimation system comprises: a collimating concave lens and a collimating convex lens which are sequentially arranged along the emergent direction of the laser;

the beam expanding and shrinking system comprises: the beam expanding and shrinking concave lens and the beam expanding and shrinking convex lens are sequentially arranged along the emergent direction of the laser.