CN110398841A - A kind of miniaturization ultraviolet laser zoom expand device - Google Patents
A kind of miniaturization ultraviolet laser zoom expand device Download PDFInfo
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- CN110398841A CN110398841A CN201810382541.3A CN201810382541A CN110398841A CN 110398841 A CN110398841 A CN 110398841A CN 201810382541 A CN201810382541 A CN 201810382541A CN 110398841 A CN110398841 A CN 110398841A
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- lens
- ultraviolet laser
- expanding system
- zoom
- multiplying power
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/09—Beam shaping, e.g. changing the cross-sectional area, not otherwise provided for
- G02B27/0938—Using specific optical elements
- G02B27/095—Refractive optical elements
- G02B27/0955—Lenses
Abstract
The present invention is suitable for laser processing technology, provides a kind of miniaturization ultraviolet laser variable power beam-expanding system, including the zoom group, compensation group and fixed group set gradually along laser transmission direction；The zoom group includes the first lens, the compensation group includes the second lens, the fixed group includes the third lens, first lens are curved month type negative lens or platycelous negative lens, second lens are double concave type negative lens, the third lens are biconvex or planoconvex positive lens, and three lens are located on the same optical axis, the present invention carries out above-mentioned setting to each lens, 2-10 times is realized to the laser that wavelength is 355nm to expand, output beam is close to diffraction limit, improve the energy density of focal beam spot, and the beam-expanding system is suitble to use in high power laser light process equipment, greatly improve the energy density of focal point, and then improve laser processing precision and processing efficiency.
Description
Technical field
The invention belongs to laser technology field more particularly to a kind of laser zooming beam-expanding systems.
Technical background
In traditional zoom beam-expanding system, the change of optical system is realized usually using three constituent elements or four component systems
Times.Three component systems are broadly divided into " Negative-Positive-Negative " type system and " Negative-Positive-Negative " type system.No matter what type, three constituent element
System is all one zoom group using a fixed group, and a compensation group realizes zoom.Wherein, fixed group can be the
One constituent element can be second constituent element, be also possible to third constituent element.Before other two constituent element is zoom group, behind
Be compensation group.And the group of four constituent element zooming systems is fixed, it may be assumed that first fixed group, zoom group, compensation group is fixed with rear
Group.Three component systems and four component systems have respective advantage and disadvantage respectively.For example, the advantages of three component systems is structure letter
It is single, if not considering color difference (most of laser systems have good monochromaticjty) and spherical aberration (most of laser system hot spot mouths
Diameter it is smaller thus introduce spherical aberration it is smaller, can usually ignore) only need three pieces of eyeglasses easily designed, cost can be completed
It is low；The disadvantage is that overall length can change with the variation of multiplying power (due to only one fixation group, so with zoom group and compensation
The change of group, system length also change constantly), in addition system is not compact enough, and the mobile distance of eyeglass is longer, and overall length also compares
It is longer.And four component systems are in contrast, since it has former and later two fixation groups, and zoom group and compensation group are only moved in centre
It is dynamic, therefore overall length will not change, moreover, four component systems are also more compact, overall length under conditions of same multiplying power
Overall length than three component systems is shorter；But that structure is complicated is some for four component systems, cost also can be higher, even
Do not consider that color difference and launching spot very little (i.e. spherical aberration is small) are also required to five eyeglasses to six eyeglasses or so (because of the spherical aberration of very little
It usually cannot be had ignored by the other amplification of four groups, additional one to two pieces of eyeglasses is needed to carry out spherical aberration corrector).Certainly,
If it is considered that color difference, then four component systems at least need 11 to 12 pieces of eyeglasses (it is generally necessary to 13 to 14).
With the development of science and technology the requirement of laser field also becomes higher and higher, cost should be considered, and need to consider light
Beam quality.In many cases, expand device can be directly placed on inside laser.Therefore shorten overall length, minimize beam-expanding system
It becomes more and more important.It has been difficult in traditional zooming system to reach the requirement of people.
Summary of the invention
The present invention provides a kind of ultraviolet laser variable power beam-expanding systems.The system aims to solve the problem that the above problem, realizes overall length
In the miniaturization of 100mm, design of the enlargement ratio in 2-10 times of big zoom laser beam expanding system.
The invention is realized in this way a ultraviolet zoom laser beam expanding system, including the direction transmitted along laser according to
The zoom group of secondary setting, compensation group and fixed group.Zoom group includes the first lens (L1), and compensation group includes the second lens (L2),
Fixed group includes the third lens (L3).The incident light bore of the ultraviolet zoom beam-expanding system is 0.1-2mm, wavelength 355nm；Institute
Stating the first lens (L1) is curved month type negative lens or platycelous negative lens, and the second lens (L2) are double concave type negative lens, and third is saturating
Mirror (L3) is biconvex or planoconvex positive lens, and three lens are located on the same optical axis.First lens (L1) and
Spacing of two lens (L2) on optical axis is d2=0.4-95mm, and second lens (L2) and the third lens (L3) are on optical axis
Spacing be d4=0.4-4.2mm.
Wherein, the multiple that expands of the d2=0.4, the d4=4.2, the ultraviolet zoom beam-expanding system are 2.
Wherein, the multiple that expands of the d2=24, the d4=1.8, the ultraviolet zoom beam-expanding system are 4.
Wherein, the multiple that expands of the d2=47.6, the d4=1, the ultraviolet zoom beam-expanding system are 6.
Wherein, the multiple that expands of the d2=71.3, the d4=0.6, the ultraviolet zoom beam-expanding system are 8.
Wherein, the multiple that expands of the d2=95, the d4=0.4, the ultraviolet zoom beam-expanding system are 10.
Wherein, first lens (L1) are made of two the curved surfaces S1 and S2 that curvature radius is respectively R1 and R2,
R1 is 19.65mm, R2 4.96mm, and the center thickness d1 on optical axis is 0.6mm.
Wherein, second lens (L2) are made of two the curved surfaces S3 and S4 that curvature radius is respectively R3 and R4,
R3 is -10.96mm, R4 12.23mm, and the center thickness d3 on optical axis is 0.6mm.
Wherein, the third lens (L3) are made of two the curved surfaces S5 and S6 that curvature radius is respectively R5 and R6,
R5 is 19.65mm, R6 4.96mm, and the center thickness d5 on optical axis is 2.4mm.
Wherein, the material of three eyeglasses of the ultraviolet zoom beam-expanding system is identical, is Nd/Vd=1.52/64.2.
The above-mentioned laser process equipment for expanding component and component is expanded with this, incident beam expose to the first lens
(L1) in first side (S1), most of incident beam is refracted into from the first side (S1) of the first lens (L1) and from first
It is reflected in the second side (S2) of lens (L1)；The second lens (L2) is exposed to by the incident beam of the first lens (L1)
First side on, most of incident beam by the first lens (L1) is reflected from the first side (S3) of the second lens (L2)
Into and from reflecting in the second side (S4) of the second lens (L2)；And so on, pass through the incidence of the first lens (L1)
Light beam largely passes through the third lens (L3), is finally focused into the thinner outgoing beam of beam diameter；In addition, the first lens (L1)
For curved month type negative lens or platycelous negative lens, its role is to: 1, parallel incident light is carried out to a small amount of divergings, 2, S1
Curvature radius is larger as far as possible, is conducive to reduce spherical aberration, and 3, move back the interarea of system, be conducive to reduce the first lens (L1)
The distance between second lens (L2)；Second lens (L2) are double concave type negative lens, and its role is to further diverging incidents
Light does not introduce too big spherical aberration simultaneously；The third lens (L3) are planoconvex positive lens after biconvex positive lens, for will be by the
Light in the incident beam of two lens (L2) pools directional light, to keep the light of the outgoing beam after focusing parallel
Light.
Detailed description of the invention
Fig. 1 is optical texture schematic diagram of the invention；
The optical-modulation transfer function MTF figure of system when Fig. 2 is 2 times of the present invention；
The optical-modulation transfer function MTF figure of system when Fig. 3 is 4 times of the present invention；
The optical-modulation transfer function MTF figure of system when Fig. 4 is 6 times of the present invention；
The optical-modulation transfer function MTF figure of system when Fig. 5 is 8 times of the present invention；
The optical-modulation transfer function MTF figure of system when Fig. 6 is 10 times of the present invention；
The point range figure of system when Fig. 7 is 2 times of the present invention；
The point range figure of system when Fig. 8 is 4 times of the present invention；
The point range figure of system when Fig. 9 is 6 times of the present invention；
The point range figure of system when Figure 10 is 8 times of the present invention；
The point range figure of system when Figure 11 is 10 times of the present invention；
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to the accompanying drawings and embodiments, right
The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and
It is not used in the restriction present invention.
Specific implementation of the invention is described in detail below in conjunction with specific embodiment:
The present invention provides a kind of ultraviolet zoom beam-expanding system in laser process equipment, being set to laser and focusing system
Between system, beam-expanding collimation processing is carried out to laser beam, to realize the focusing effect close to diffraction limit by focusing system, is mentioned
The energy density of high focus point.
The present invention is calculated in the theoretical basis of Application Optics, is deduced, design, what experiment was finally realized.
According to Laplace invariant: J=nwD=n'w'D '.Wherein, D and D' is the Entry pupil diameters and emergent pupil of system
Diameter.For this beam-expanding system, D and D' respectively represent unpolarized light beam diameter and exiting light beams diameter.Equally, according to drawing
Family name's invariant will also be appreciated that emergent light can also have a degree of hair if incident beam is there are certain angle of divergence
It dissipates, and the angle of divergence is the 1/M of incident light.If the angle of divergence of emergent light can be smaller by some special processing.According to
The requirement of actual conditions, the present invention are subjected to the angle of divergence < 2mrad of incident light.
According to theory of geometric optics, what two constituent elements determined times beam-expanding system expands ratioSystem overall length T=f1'
+f2'.As a result, we it is found that system f1' smaller, overall length is smaller.Therefore, it expands than under conditions of certain, negative-positive system is wanted
Distance shorter than n- positive system and short are as follows: δ=| 2f1'|.In addition, the focal length of each constituent element of two component systems be it is fixed,
Therefore, two component systems cannot achieve zoom.
According to the focal length formula of combined systemWherein △ is optical interval, the i.e. image space of first lens
Focus to second lens object focus distance, we it is found that by change two eyeglasses distance can change system
Total focal length.So the first constituent element of the fixed times beam-expanding system of two constituent elements is resolved into two constituent elements by us, by change this two
The distance of a constituent element realizes the change of total focal power.Then the zoom beam-expanding system of available three constituent element.
According to the focal power formula of beam-expanding system expanded than formula and combined system, our available three component systems
Expand than formula:It is found that comparing to obtain bigger expanding, perhaps increasing optical interval △ or subtracting
It is small | f1'f2' | value.Therefore we are such as drawn a conclusion: 1, in order to reduce overall length, need to reduce optical interval △, but light
It is smaller to learn interval △, expands than smaller；2,f1' and f2' smaller overall length is smaller, therefore the first constituent element and the second constituent element are negative group
Overall length can be short, but more negative, | f1'f2' | value it is bigger, expand than smaller.In other words ,-negative-positive system more easily contracting is born
Short overall length, but be not easily achieved and bigger expand ratio.This is also that traditional zoom beam-expanding system all uses Negative-Positive-Negative system,
And one of few the reason of using negative-negative-positive system.
From another perspective: note f' is the combined focal length of the first constituent element and the second constituent element.According to expanding than formula and group
Close system focal length formula, it is known that, the distance of the first constituent element and the second constituent element is close when small multiplying power, the first constituent element and second when big multiplying power
The distance of constituent element is remote.It is discussed herein expand than M be 2-10 times the case where.When 2 times, the distance of the first constituent element and the second constituent element
Recently, for convenience discuss, take here the limiting case i.e. spacing of the first constituent element and the second constituent element be 0, i.e., optical interval Δ=-
f1'-f2', at this timeNext, the distance of the first constituent element and the second constituent element is farthest when 10 times,At this point, the very big (f of Δ=- 5 of optical interval1'+f2'), system is also at longest state.It connects down
The distance of second constituent element and third element is discussed, total length when due to small multiplying power, and the distance of the second constituent element and third element
Bigger, there is no the situations under arranging not, therefore only need to discuss the second constituent element and third element in the case of 10 times of big multiplying power
Distance.According to the principal point formula of combined systemWherein xH' for the principal point H' to the of combined system
The distance of the rear focus of two constituent elements.According to several optical theories: f3'=- ffar'+|xH'|-f2'+d4, can obtainAbsolute value divides situation discussion: 1, as 0 > f1' > f2', have at this time
Without solution.2, as 0 > f2' > f1', have at this time
It is available such as to draw a conclusion by above discussion: 1, not consider lens thickness, overall length d2max+d4=-4 (f1'
+f2')+d4In view of current machining capabilities, the focal length of lens is not suitable for being lower than 10.And in order to reduce overall length, focal length will also use up can
Can it is small.Therefore, we take the situation of L2 focal length minimum, f2'=- 10mm, can be in the hope of f1'=- 13mm f3'=12mm.This
Shi overall length is about 95mm.2, lens thickness and aberration and mismachining tolerance are considered moreover, the first constituent element and second group when small multiplying power
Interval between member is also impossible to be 0, so, want to accomplish that overall length is less than the zoom beam-expanding system of 100mm, the limit is expanded than also
In 2-10 or so.To which although also having turned out negative and positive system can be shortened overall length, but zoom ratio can reduce.This is also to pass
System zooming system does not use negative-negative-positive one of reason.
Invention is further explained for a specific embodiment presented below.
The parameter of incident laser of the present invention: bore 0.1-2mm, wavelength 355nm, the angle of divergence < 2mrad.
The present invention claims the parameters of shoot laser: expanding multiplying power is M (2≤M≤10), zoom ratio: 5X
The present invention claims optical system parameter: eyeglass number 3, overall length < 100mm.
Embodiment:
According to the needs of different actual conditions, d2, the d4 at curved surface interval are adjusted, realizes zoom adjustment, corresponding relationship is as follows:
The modulation transfer function figure of ultraviolet zoom beam-expanding system of the invention is as shown in Fig. 2-Fig. 6, we can from figure
To see transfer curve all close to diffraction limit, good beam quality.
The point range figure of ultraviolet zoom beam-expanding system of the invention is as shown in Fig. 7-Figure 11, and Cong Tuzhong is it may be seen that disperse
Spot is all within Airy radius, good beam quality.
Claims (10)
1. a kind of ultraviolet laser zoom beam-expanding system for minimizing big multiplying power, which is characterized in that including along laser transmission side
To the zoom group, compensation group and fixed group set gradually；The zoom group includes the first lens, and the compensation group includes the
Two lens, the described fixed group include the third lens, and first lens are curved month type negative lens or platycelous negative lens, and second
Lens are double concave type negative lens, and the third lens are biconvex or planoconvex positive lens, and three lens are located on the same optical axis,
The combination of the zoom group and compensation group constitutes ultraviolet laser described in the structure of galilean telescope system with fixed group and expands
System is 355nm to wavelength, and the multiplying power that expands of spot diameter 100-1000um, laser beam of the angle of divergence less than 2mrad are
2-10 times, output facula can reach diffraction limit.
2. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as described in claim 1, which is characterized in that the change
The first lens of group include first surface and the second curved surface again, and second lens of compensation group include that third curved surface and the 4th are bent
Face, the fixed group the third lens include the 5th curved surface and the 6th curved surface.
3. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 2, which is characterized in that described
The radius of curvature of one curved surface is 19.65mm, and the radius of curvature of the second curved surface is 4.96mm, the radius of curvature of third curved surface is-
10.96mm, the radius of curvature of the 4th curved surface are 12.23mm, and the radius of curvature of the 5th curved surface is 15.24mm, the song of the 6th curved surface
Rate radius is -9.54mm, and the tolerance of each radius of curvature is ± 5%.
4. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The center thickness of one lens is 0.6mm, and the center thickness of second lens is 0.6mm, the center of the third lens
With a thickness of 2.4mm, the tolerance of each center thickness is ± 5%.
5. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The airspace of one lens and the second lens is 0.4mm, and the airspace of the second lens and the third lens is 4.2mm, each air
The tolerance at interval is ± 5%, and the enlargement ratio of the ultraviolet laser beam-expanding system is 2 times.
6. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The airspace of one lens and the second lens is 24mm, and the airspace of the second lens and the third lens is 1.8mm, between each air
Every tolerance be ± 5%, the enlargement ratio of the ultraviolet laser beam-expanding system is 4 times.
7. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The airspace of one lens and the second lens is 47.6mm, and the airspace of the second lens and the third lens is 1mm, between each air
Every tolerance be ± 5%, the enlargement ratio of the ultraviolet laser beam-expanding system is 6 times.
8. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The airspace of one lens and the second lens is 71.3mm, and the airspace of the second lens and the third lens is 0.6mm, each air
The tolerance at interval is ± 5%, and the enlargement ratio of the ultraviolet laser beam-expanding system is 8 times.
9. minimizing big multiplying power ultraviolet laser zoom beam-expanding system as claimed in claim 3, which is characterized in that described
The airspace of one lens and the second lens is 95mm, and the airspace of the second lens and the third lens is 0.4mm, between each air
Every tolerance be ± 5%, the enlargement ratio of the ultraviolet laser beam-expanding system is 10 times.
10. such as the described in any item big multiplying power ultraviolet laser zoom beam-expanding systems of miniaturization of claim 2 to 9, feature exists
In the material of first lens, the second lens and the third lens is Nd/Vd=1.5/64, wherein the tolerance of refractive index Nd value
It is ± 0.07, the tolerance of Abbe number Vd value is ± 5%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810382541.3A CN110398841A (en) | 2018-04-24 | 2018-04-24 | A kind of miniaturization ultraviolet laser zoom expand device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810382541.3A CN110398841A (en) | 2018-04-24 | 2018-04-24 | A kind of miniaturization ultraviolet laser zoom expand device |
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| CN110398841A true CN110398841A (en) | 2019-11-01 |
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| CN201810382541.3A Pending CN110398841A (en) | 2018-04-24 | 2018-04-24 | A kind of miniaturization ultraviolet laser zoom expand device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112872582A (en) * | 2020-12-29 | 2021-06-01 | 武汉华工激光工程有限责任公司 | Continuously adjustable large-size shaping system and method |
| CN113319434A (en) * | 2021-06-28 | 2021-08-31 | 苏州赛腾精密电子股份有限公司 | Laser line width adjusting method and laser marking device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000275568A (en) * | 1999-03-25 | 2000-10-06 | Sumitomo Heavy Ind Ltd | Beam mode converting optical system |
| RU89727U1 (en) * | 2009-07-27 | 2009-12-10 | Российская академия наук. Сибирское отделение. Институт мониторинга климатический и экологических систем | ACHROMATIC LASER BEAM EXPANDER FOR UV AND IR SPECTRUM AREAS |
| US9069170B1 (en) * | 2012-07-18 | 2015-06-30 | Han's Laser Technology Industry Group Co., Ltd. | Ultraviolet laser zoom beam expanding system and laser processing equipment |
| CN206696536U (en) * | 2017-04-13 | 2017-12-01 | 上海仪万光电科技有限公司 | A kind of Ultra-Violet Laser continuous zoom beam expanding lens |
-
2018
- 2018-04-24 CN CN201810382541.3A patent/CN110398841A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000275568A (en) * | 1999-03-25 | 2000-10-06 | Sumitomo Heavy Ind Ltd | Beam mode converting optical system |
| RU89727U1 (en) * | 2009-07-27 | 2009-12-10 | Российская академия наук. Сибирское отделение. Институт мониторинга климатический и экологических систем | ACHROMATIC LASER BEAM EXPANDER FOR UV AND IR SPECTRUM AREAS |
| US9069170B1 (en) * | 2012-07-18 | 2015-06-30 | Han's Laser Technology Industry Group Co., Ltd. | Ultraviolet laser zoom beam expanding system and laser processing equipment |
| CN206696536U (en) * | 2017-04-13 | 2017-12-01 | 上海仪万光电科技有限公司 | A kind of Ultra-Violet Laser continuous zoom beam expanding lens |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112872582A (en) * | 2020-12-29 | 2021-06-01 | 武汉华工激光工程有限责任公司 | Continuously adjustable large-size shaping system and method |
| CN113319434A (en) * | 2021-06-28 | 2021-08-31 | 苏州赛腾精密电子股份有限公司 | Laser line width adjusting method and laser marking device |
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Application publication date: 20191101 |