CN108288814A - A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens - Google Patents
A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens Download PDFInfo
- Publication number
- CN108288814A CN108288814A CN201810284412.0A CN201810284412A CN108288814A CN 108288814 A CN108288814 A CN 108288814A CN 201810284412 A CN201810284412 A CN 201810284412A CN 108288814 A CN108288814 A CN 108288814A
- Authority
- CN
- China
- Prior art keywords
- focal length
- spherical aberration
- laser crystal
- coefficient
- zernike
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
-
- 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
- G02B27/0012—Optical design, e.g. procedures, algorithms, optimisation routines
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- General Physics & Mathematics (AREA)
- Lasers (AREA)
Abstract
The invention discloses it is a kind of obtain laser crystal thermal lens focal length and spherical aberration method and apparatus, the method includes：Determine the inverse model between wavefront information and laser crystal thermal focal length and spherical aberration；It determines or measures to obtain inverted parameters collection；Inverse model between the inverted parameters and wavefront information and laser crystal thermal focal length and spherical aberration concentrated based on inverted parameters, obtains laser crystal thermal focal length and spherical aberration.The beneficial effects of the invention are as follows：Consider actual conditions of the wavefront information by thermal focal length and spherical aberration joint effect, obtain the inverse model between more complete wavefront information and laser crystal thermal focal length and spherical aberration, avoid the imperfection to beam quality analysis of Influential Factors, to be more advantageous to the thermal lensing effect and spherical aberration effect distribution situation that analysis gain media generates in the operating condition, advantageous foundation is provided to improve laser output characteristic and improving Resonator design.
Description
Technical field
The present invention relates to field of lasers, especially a kind of wavefront information inverting using laser beam obtains laser crystal heat
The method and apparatus of the focal length of lens and spherical aberration.
Background technology
The fuel factor of laser crystal is an important factor for influencing laser device laser performance, to directly affect laser resonator
The problems such as stability, beam quality and output power.In the operating condition, a part of pump light is converted into output and swashs laser
Light, another part form heat deposition in crystal, will produce temperature gradient at this time, and temperature gradient results in refractive index ladder again
Degree, therefore will produce thermal lensing effect.Wavefront distortion can occur after thermal lens for laser, so thermal lens is not ideal saturating
Mirror is the lens containing spherical aberration.In addition, when the pump power of laser from low to high when, the thermal focal length of laser crystal can be by
Gradual change is short, and resonant cavity on the one hand can be made to deviate stable oscillation stationary vibration condition and enable laser unstable；On the other hand it can make output
Laser beam quality deteriorates.Therefore, the accurate focal length for measuring laser heat lens and spherical aberration are for high stability, high light beam quality
The design of laser is vital.Currently, the method master of the focal length and spherical aberration of the acquisition laser heat lens of open report
If based on the considerations of focusing or spherical aberration single factors, laser thermal lensing effect and spherical aberration at work are not accounted for
The fact that effect is existed simultaneously, interacted, the considerations of lacking influence factor, to have the analysis that fuel factor influences endless
Whole property, it is not comprehensive enough accurate.
Invention content
Incomplete in order to solve the problems, such as to exist in the prior art above-mentioned basic associated arguments, the present invention combines the two altogether
With the harmful effect to laser output characteristic, wavefront information and thermal focal length and the triangular theoretical model of spherical aberration are established,
A kind of method and apparatus according to wavefront information Simultaneous Inversion thermal focal length and spherical aberration are proposed, present invention improves for shadow
The problem for ringing beam quality Consideration deficiency, more accurately analyzes thermal lensing effect and spherical aberration effect exists simultaneously, simultaneously
The actual conditions of effect.
According to an aspect of the invention, it is proposed that a kind of method for the focal length and spherical aberration obtaining laser crystal thermal lens, described
Method includes the following steps：
Step S1 determines the inverse model between wavefront information and laser crystal thermal focal length and spherical aberration, wherein described
Wavefront information includes Zernike coefficient of spherical aberrations CZerWith beam quality factor M2；
Step S2 determines or measures to obtain inverted parameters collection, and the inverted parameters collection includes：Thermal stress coefficient ε (γ), wave
The radius r of number k, crystal0, wavelength X, basic mode angle of divergence θ0, basement membrane waist radius w0And wavefront information；
Step S3, inverted parameters and the wavefront information and the laser crystal thermal lens concentrated based on the inverted parameters
Inverse model between focal length and spherical aberration obtains laser crystal thermal focal length and spherical aberration.
Optionally, the step S1 further comprises the steps：
Step S11 establishes beam quality factor M2Pass between the focal length and Zernike spherical aberrations of laser crystal thermal lens
It is model；
Step S12 determines basic mode waist radius w0With the relational model w between laser crystal thermal focal length f0(f)；
Step S13 considers the thermal stress coefficient ε (γ) for influencing spherical aberration item, adjustment beam quality factor M2With laser crystal
Relational model between the focal length and Zernike spherical aberrations of thermal lens；
Step S14 determines wavefront information Zernike coefficient of spherical aberrations CZerWith the inverse model between laser crystal spherical aberration；
Step S15 determines wavefront information beam quality factor M2With Zernike coefficient of spherical aberrations CZerWith laser crystal heat penetration
Inverse model between mirror focal length.
Optionally, the step S11 includes the following steps：
Step S111 establishes the relational model between Seidel aberration and Saden that coefficient of spherical aberration；
Step S112 establishes the relational model between Saden that coefficient of spherical aberration and Zernike coefficient of spherical aberrations；
Step S113 establishes beam quality factor M2With the pass between laser crystal thermal focal length and Zernike spherical aberrations
It is model.
Optionally, the beam quality factor M2Pass between the focal length and Zernike spherical aberrations of laser crystal thermal lens
It is that model is expressed as：
Wherein, k is wave number,λ indicates wavelength, CZerIndicate Zernike coefficient of spherical aberrations, r0Indicate the half of crystal
Diameter.
Optionally, basic mode waist radius w0With the relational model w between laser crystal thermal focal length f0(f) it is expressed as：
Wherein, λ indicate wavelength, a, b be used for characterize light incident reference face and be emitted the plane of reference between optical element it is close
Axis focussing property, g1And g2Indicate the resonant cavity geometric parameter factor.
Optionally, the beam quality factor M after adjustment2Between the focal length and Zernike spherical aberrations of laser crystal thermal lens
Relational model be expressed as：
Wherein, k is wave number,λ indicates that wavelength, ε (γ) indicate thermal stress coefficient, CZerIndicate Zernike spherical aberrations
Coefficient, r0Indicate the radius of crystal.
Optionally, the wavefront information Zernike coefficient of spherical aberrations CZerInverse model between laser crystal spherical aberration indicates
For：
Wherein, CcrystalIndicate laser crystal spherical aberration, δ LiIndicate the spherical aberration value of each lens in optical system.
Optionally, the wavefront information beam quality factor M2With Zernike coefficient of spherical aberrations CZerWith laser crystal thermal lens
Inverse model between focal length is expressed as：
Wherein, r0Indicating the radius of crystal, k is wave number,λ indicates that wavelength, ε (γ) indicate thermal stress coefficient.
According to another aspect of the present invention, it is also proposed that a kind of device for the focal length and spherical aberration obtaining laser crystal thermal lens,
Described device includes：Pumping source, input mirror, the first total reflective mirror, Nd:YVO4Crystal, outgoing mirror, the second total reflective mirror, third are all-trans
Mirror, attenuator, coupled lens group, Wavefront sensor, wherein：
The input mirror, the first total reflective mirror, Nd:YVO4Crystal, outgoing mirror, the second total reflective mirror, third total reflective mirror, decaying
Piece, coupled lens group and Wavefront sensor are sequentially placed along light path；
The pumping source is placed on the side of first total reflective mirror, and pump light source is provided for it.
Optionally, the Wavefront sensor is Shack-Hartmann wavefront sensor.
The beneficial effects of the invention are as follows：Consider practical feelings of the wavefront information by thermal focal length and spherical aberration joint effect
Condition obtains the internal relation of more complete beam quality and thermal focal length and spherical aberration, avoids to beam quality influence factor
The imperfection of analysis, to be more advantageous to the thermal lensing effect and spherical aberration effect that analysis gain media generates in the operating condition
Distribution situation provides advantageous foundation to improve laser output characteristic and improving Resonator design.
Description of the drawings
Fig. 1 is the method flow of the focal length and spherical aberration according to a kind of acquisition laser crystal thermal lens of one embodiment of the invention
Figure；
Fig. 2 is the knot according to a kind of device of the focal length and spherical aberration of acquisition laser crystal thermal lens of one embodiment of the invention
Structure schematic diagram.
Meaning in Fig. 2 represented by each reference numeral is：1, pumping source；2, mirror is inputted；3,808nm total reflective mirrors one；4、Nd:
YVO4Crystal；5, outgoing mirror；6,808nm total reflective mirrors two；7,1064nm total reflective mirrors；8, attenuator；9, coupled lens group 10, Hart
Graceful-Shack Wavefront sensor.
Specific implementation mode
To make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with specific embodiment, and reference
Attached drawing, the present invention is described in more detail.
According to an aspect of the invention, it is proposed that a kind of method for the focal length and spherical aberration obtaining laser crystal thermal lens, such as Fig. 1
It is shown, it the described method comprises the following steps：
Step S1 determines the inverse model between wavefront information and laser crystal thermal focal length and spherical aberration, wherein described
Wavefront information includes Zernike coefficient of spherical aberrations CZerWith beam quality factor M2；
The step S1 further comprises the steps：
Step S11 establishes beam quality factor M2Pass between the focal length and Zernike spherical aberrations of laser crystal thermal lens
It is model；
In an embodiment of the present invention, the step S11, that is, establish beam quality factor M2With laser crystal thermal lens
The step of focal length and the relational model of spherical aberration, includes the following steps：
Step S111 establishes the relational model between Seidel aberration and Saden that coefficient of spherical aberration；
According to your primary aberration theory of Saden, if the case where only considering primary spherical aberration, aberration function radially more than four times
Item formula, is represented by：
W (r)=C0+C2r2+C4r4 (1)
Wherein, W (r) indicates Seidel aberration, C0For constant term；C2It indicates to focus item；C4It, can for Saden that coefficient of spherical aberration
The size of your spherical aberration of Saden is characterized, r indicates radial coordinate (radial coordinate).
Step S112 establishes the relational model between Saden that coefficient of spherical aberration and Zernike coefficient of spherical aberrations；
Since Zernike multinomials have orthogonality and circular symmetry, this is consistent with the property of hot spot, so the present embodiment
Use Zernike polynomial repressentation optical distortions.According to the circular symmetry of hot spot, it converts rectangular coordinate system to polar coordinate system,
Optical path difference is distributed and is obtained with Zernike polynomial expansions：
Wherein, W (ρ, θ) indicates that optical path difference distribution, ρ and θ are polar coordinates, and n is radial exponent number, and m is angular exponent number, and m and n are
It is positive integer,For the n rank Zernike multinomials under polar form, cnmFor each rank Seidel aberration coefficient.
In Zernike multinomials, spherical aberration item is represented by：In conjunction with formula (1)
Shown in Saden your primary aberration quartic polynomial the relationship between your coefficient of spherical aberration of Saden and Zernike coefficient of spherical aberrations can be obtained
Meet：
R in formula0Indicate the radius of crystal, C4Indicate Saden that coefficient of spherical aberration, CZerIndicate Zernike coefficient of spherical aberrations.
Step S113 establishes beam quality factor M2With the pass between laser crystal thermal focal length and Zernike spherical aberrations
It is model.
According to Neubert B J (《Influences on the beam propagation ratio M2》Optics
Communication the beam quality factor M) proposed2Can by represent beam quality component intensity itemize, phase subitem,
Relevant three parameters of subitem are constituted, then beam quality factor can be analyzed to：
Wherein M2 diffIndicate intensity subitem, M2 abIndicate phase subitem, M2 coheIndicate relevant subitem.The coherence of laser is non-
Chang Hao, therefore have been generally acknowledged that M2 cohe=0.In the present embodiment, it is assumed that the intensity distribution of light is Gaussian Profile, then intensity is itemized
M2 diff=1 (spherical aberration is to influence the maximum factor of phase distribution, so particular analysis phase distribution in the present embodiment), phase point
Relationship between item parameter and coefficient of spherical aberration is represented by：
Wherein, λ indicates wavelength, w0Indicate basement membrane waist radius, basement membrane waist radius w0With laser crystal thermal focal length f
There is corresponding functional relations, therefore phase subitem parameter is represented by：
So in the influence for ignoring light distribution, beam quality factor is represented by：
Wherein, k is wave number,
Step S12 determines basic mode waist radius w0With the relational model w between laser crystal thermal focal length f0(f)；
If thermal focal length is f in stable cavity, the distance away from two speculums is respectively d1And d2, the curvature of resonator mirror
Radius is respectively R1And R2, then the Ray Matrix of intracavitary be represented by：
Wherein, matrix element a, b, c, d characterize light incident reference face and be emitted the plane of reference between optical element it is paraxial
Focussing property.
According to stable resonator standard transmission matrix theory, above formula can be indicated with g parameters of equal value：
Wherein, g1And g2Indicate the resonant cavity geometric parameter factor, R1And R2Indicate the radius of curvature of two hysteroscopes of resonant cavity.
According to multimode theory, basic mode angle of divergence θ0It is represented by,：
Wherein, θrFor far-field divergence angle, then basic mode waist radius w0With the relationship between laser crystal thermal focal length f
Model is represented by：
Step S13 considers the thermal stress coefficient ε (γ) for influencing spherical aberration item, adjustment beam quality factor M2With laser crystal
Relational model between the focal length and Zernike spherical aberrations of thermal lens；
Since temperature distributing disproportionation causes the stress distribution in laser crystal uneven, also just directly result in laser crystal
Portion generates refractive index gradient, it is contemplated that distribution function, thermo-optical coeffecient and coefficient of thermal expansion inside laser crystal, it will be in laser crystal
The distribution function of refractive index is expressed as：
N (r)=n0(1-γ·r2)+Γr4 (12)
Wherein, n (r) is laser crystal refractive index (laser crystal index), wherein n0Numerical value is that 1.82, r is indicated
Radial coordinate, two-term coefficient γ indicate that the power of thermal lensing effect, four term coefficient Γ indicate the power of spherical aberration effect.
Optical path difference (OPD) between wavefront with spherical aberration effect and ideal spherical face wave wavefront can in Gaussian approximation
It is expressed as：
Wherein, r (z) indicates that path of the light beam in laser crystal, L indicate that the length of laser crystal, n (r (z)) indicate ball
The wavefront light path of poor effect, nref(r (z)) indicates ideal spherical face wave wavefront light path.
The expression formula of optical path difference (OPD) between the above-mentioned wavefront with spherical aberration effect and ideal spherical face wave wavefront can simplify
It is expressed as：
OPD (r)=ε (γ) Γ r4L (14)
Wherein, ε (γ) indicates thermal stress coefficient.
As can be seen from the above equation, influence spherical aberration power be four term coefficient Γ, thermal stress coefficient ε (γ) and laser crystal
Length L, wherein thermal stress coefficient ε (γ) is the function about r and γ, and corresponding above formula (12), it is related with thermal focal length
Parameter, spherical aberration effect at this time influenced by thermal focal length.Understand that spherical aberration and thermal focal length are two relevant mutual shadows
Loud parameter.Separately it is known that thermal stress coefficient ε (γ) is related with the distribution situation of laser bar inner light beam, light beam is in laser medium
It is distributed as taking 0.9 when symmetry status, when collimation takes 0.7.
Therefore, based on the thermal stress coefficient ε (γ) for influencing spherical aberration item, as spherical aberration parameter, by beam quality factor
M2Relational model between the focal length and spherical aberration of laser crystal thermal lens is adjusted to：
Step S14 determines wavefront information Zernike coefficient of spherical aberrations CZerWith the inverse model between laser crystal spherical aberration；
There is additive principle according to spherical aberration, the expression of spherical aberration sum can be obtained：Wherein δ LiFor optics
The spherical aberration value of each lens in system, according to the spherical aberration and can inverting obtain the spherical aberration of laser crystal.
Since lens centre region is different for the aggregate capabilities of incidence wave from edge, then in optical system, total spherical aberration
Value be each lens generate spherical aberration and.Therefore it is optical system by the spherical aberration value that Shack-Hartmann wavefront sensor measures
In each lens spherical aberration it is cumulative after as a result, wavefront information Zernike coefficient of spherical aberrations C can be based on according to the following formulaZerInverting obtains laser
The spherical aberration C of crystalcrystal：
Step S15 determines wavefront information beam quality factor M2With Zernike coefficient of spherical aberrations CZerWith laser crystal heat penetration
Inverse model between mirror focal length.
According to first three step, with basement membrane waist radius w0For bridge, wavefront information beam quality can be passed through based on following formula
Factor M2With Zernike coefficient of spherical aberrations CZerInverting obtains laser crystal thermal focal length w0(f)：
Step S2 determines or measures to obtain inverted parameters collection, and the inverted parameters collection includes：Thermal stress coefficient ε (γ), wave
The radius r of number k, crystal0, wavelength X, basic mode angle of divergence θ0, basement membrane waist radius w0And wavefront information (Zernike spherical aberrations system
Number CZerWith beam quality factor M2)；
Wherein, for thermal stress coefficient ε (γ), when light beam is taken as 0.9 in laser medium when being distributed as symmetry status,
0.7 is taken as when collimation；Wave numberRelated with λ, wherein λ is the wavelength of optical system outgoing laser beam in practical operation, because
In each practical operation, k and λ is fixed value for this；r0It is a fixed value, according to selected crystal for crystal radius
Type determines；Basic mode angle of divergence θ0, wavefront information Zernike coefficient of spherical aberrations CZerWith beam quality factor M2And basement membrane is with a tight waist
Radius w0It is obtained by measuring.
Step S3, inverted parameters and the wavefront information and the laser crystal heat penetration concentrated based on the inverted parameters
Inverse model between mirror focal length and spherical aberration obtains laser crystal thermal focal length and spherical aberration.
Fig. 2 is the knot according to a kind of device of the focal length and spherical aberration of acquisition laser crystal thermal lens of one embodiment of the invention
Structure schematic diagram, as shown in Fig. 2, described device includes：Pumping source 1, input mirror 2, the first total reflective mirror 3, Nd:YVO4Crystal 4, output
Mirror 5, the second total reflective mirror 6, third total reflective mirror 7, attenuator 8, coupled lens group 9, Wavefront sensor 10, wherein：
The input mirror 2, the first total reflective mirror 3, Nd:YVO4Crystal 4, outgoing mirror 5, the second total reflective mirror 6, third total reflective mirror 7,
Attenuator 8, coupled lens group 9 and Wavefront sensor 10 are sequentially placed along light path；
The pumping source 1 is placed on the side of first total reflective mirror 3, and pump light source is provided for it.
In an embodiment of the present invention, first total reflective mirror 3 is 808nm total reflective mirrors, and the second total reflective mirror 6 is that 808nm is complete
Anti- mirror, third total reflective mirror 7 are 1064nm total reflective mirrors.
In an embodiment of the present invention, the Wavefront sensor 10 passes for Shark-Hatmann (Shack-Hartmann) wavefront
Sensor.
In an embodiment of the present invention, the Nd:YVO4The doping concentration of crystal 4 is 0.3%, and size is 3 × 10mm of φ
(a diameter of 3mm, length are the cylindrical type crystal of 10mm).
Laser is radiated by the heat sink recirculated water cooling of red copper, and symmetrically average chamber, a length of 200mm of chamber are (defeated for experimental construction
Enter mirror 2 and arrive the distance between outgoing mirror 5).
In this embodiment, for the device, crystal radius r0=3；Wavelength X=1064nm；Wave numberThermal stress coefficient ε (γ)=0.9；By selecting 10 weight of Shark-Hatmann Wavefront sensors
Structure wavefront information can directly record parameter basic mode angle of divergence θ0, Zernike coefficient of spherical aberrations CZerWith beam quality factor M2, survey indirectly
Measure basement membrane waist radius w0.By above-mentioned parameter ε (γ), k, r0、CZer, λ substitutions bring into shown in formula (16) and (17) instead
It drills in model, you can obtain the focal length and spherical aberration of laser crystal thermal lens using the wavefront information Simultaneous Inversion of laser beam.
Particular embodiments described above has carried out further in detail the purpose of the present invention, technical solution and advantageous effect
It describes in detail bright, it should be understood that the above is only a specific embodiment of the present invention, is not intended to restrict the invention, it is all
Within the spirit and principles in the present invention, any modification, equivalent substitution, improvement and etc. done should be included in the guarantor of the present invention
Within the scope of shield.
Claims (10)
1. a kind of method for the focal length and spherical aberration obtaining laser crystal thermal lens, which is characterized in that the method includes：
Step S1 determines the inverse model between wavefront information and laser crystal thermal focal length and spherical aberration, wherein the wavefront
Information includes Zernike coefficient of spherical aberrations CZerWith beam quality factor M2；
Step S2 determines or measures to obtain inverted parameters collection, and the inverted parameters collection includes：Thermal stress coefficient ε (γ), wave number k,
The radius r of crystal0, wavelength X, basic mode angle of divergence θ0, basement membrane waist radius w0And wavefront information；
Step S3, inverted parameters and the wavefront information and the laser crystal thermal focal length concentrated based on the inverted parameters
Inverse model between spherical aberration obtains laser crystal thermal focal length and spherical aberration.
2. according to the method described in claim 1, it is characterized in that, the step S1 further comprises the steps：
Step S11 establishes beam quality factor M2Relationship mould between the focal length and Zernike spherical aberrations of laser crystal thermal lens
Type；
Step S12 determines basic mode waist radius w0With the relational model w between laser crystal thermal focal length f0(f)；
Step S13 considers the thermal stress coefficient ε (γ) for influencing spherical aberration item, adjustment beam quality factor M2With laser crystal thermal lens
Focal length and Zernike spherical aberrations between relational model；
Step S14 determines wavefront information Zernike coefficient of spherical aberrations CZerWith the inverse model between laser crystal spherical aberration；
Step S15 determines wavefront information beam quality factor M2With Zernike coefficient of spherical aberrations CZerWith laser crystal thermal focal length
Between inverse model.
3. according to the method described in claim 2, it is characterized in that, the step S11 includes the following steps：
Step S111 establishes the relational model between Seidel aberration and Saden that coefficient of spherical aberration；
Step S112 establishes the relational model between Saden that coefficient of spherical aberration and Zernike coefficient of spherical aberrations；
Step S113 establishes beam quality factor M2Relationship mould between laser crystal thermal focal length and Zernike spherical aberrations
Type.
4. according to the method in claim 2 or 3, which is characterized in that the beam quality factor M2With laser crystal thermal lens
Focal length and Zernike spherical aberrations between relational model be expressed as：
Wherein, k is wave number,λ indicates wavelength, CZerIndicate Zernike coefficient of spherical aberrations, r0Indicate the radius of crystal.
5. according to the method in claim 2 or 3, which is characterized in that basic mode waist radius w0With laser crystal thermal focal length
Relational model w between f0(f) it is expressed as：
Wherein, λ indicates that wavelength, a, b are used to characterize the paraxial of optical element between light incident reference face and the outgoing plane of reference and gather
Burnt property, g1And g2Indicate the resonant cavity geometric parameter factor.
6. according to the method described in claim 2, it is characterized in that, adjustment after beam quality factor M2With laser crystal heat penetration
Relational model between the focal length and Zernike spherical aberrations of mirror is expressed as：
Wherein, k is wave number,λ indicates that wavelength, ε (γ) indicate thermal stress coefficient, CZerIndicate Zernike coefficient of spherical aberrations,
r0Indicate the radius of crystal.
7. according to the method described in claim 2, it is characterized in that, the wavefront information Zernike coefficient of spherical aberrations CZerWith laser
Inverse model between crystal spherical aberration is expressed as：
Wherein, CcrystalIndicate laser crystal spherical aberration, δ LiIndicate the spherical aberration value of each lens in optical system.
8. according to the method described in claim 2, it is characterized in that, the wavefront information beam quality factor M2With Zernike balls
Poor coefficient CZerInverse model between laser crystal thermal focal length is expressed as：
Wherein, r0Indicating the radius of crystal, k is wave number,λ indicates that wavelength, ε (γ) indicate thermal stress coefficient.
9. a kind of device for the focal length and spherical aberration obtaining laser crystal thermal lens, which is characterized in that described device includes：Pumping
Source, input mirror, the first total reflective mirror, Nd:YVO4Crystal, outgoing mirror, the second total reflective mirror, third total reflective mirror, attenuator, coupled lens
Group, Wavefront sensor, wherein：
The input mirror, the first total reflective mirror, Nd:YVO4Crystal, outgoing mirror, the second total reflective mirror, third total reflective mirror, attenuator, coupling
Lens group and Wavefront sensor are sequentially placed along light path；
The pumping source is placed on the side of first total reflective mirror, and pump light source is provided for it.
10. device according to claim 9, which is characterized in that the Wavefront sensor is Shack-Hartmann wavefront sensing
Device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810284412.0A CN108288814A (en) | 2018-04-02 | 2018-04-02 | A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810284412.0A CN108288814A (en) | 2018-04-02 | 2018-04-02 | A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108288814A true CN108288814A (en) | 2018-07-17 |
Family
ID=62834061
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810284412.0A Pending CN108288814A (en) | 2018-04-02 | 2018-04-02 | A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108288814A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108873615A (en) * | 2018-06-12 | 2018-11-23 | 中国科学院上海光学精密机械研究所 | The rapid simulation method of photoetching projection objective lens thermal aberration |
| CN109742642A (en) * | 2019-01-31 | 2019-05-10 | 华中科技大学 | A kind of solid state laser thermal lens focal length method and device |
| CN110471144A (en) * | 2019-08-07 | 2019-11-19 | 北京工业大学 | A kind of myriawatt grade optical fiber connector of anaberration |
| CN113557463A (en) * | 2019-03-08 | 2021-10-26 | Pcms控股公司 | Optical method and system for display based on light beam with extended focal depth |
| CN114924411A (en) * | 2022-05-30 | 2022-08-19 | 中国人民解放军国防科技大学 | Light beam transformation system design method for medium and long distance laser Doppler velocimeter |
| CN116698362A (en) * | 2023-02-23 | 2023-09-05 | 武汉华日精密激光股份有限公司 | Method and device for measuring focal length of end-pumped laser crystal thermal lens |
-
2018
- 2018-04-02 CN CN201810284412.0A patent/CN108288814A/en active Pending
Non-Patent Citations (3)
| Title |
|---|
| 于淼: "热致BBO相位失配对266nm紫外激光转换效率影响的研究", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
| 王启晗 等: "热透镜焦距和球差影像光束质量的分析模型", 《中国学术期刊网络出版总库》 * |
| 王启晗等: "热透镜焦距和球差影响光束质量的分析模型", 《激光与光电子进展》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108873615A (en) * | 2018-06-12 | 2018-11-23 | 中国科学院上海光学精密机械研究所 | The rapid simulation method of photoetching projection objective lens thermal aberration |
| CN109742642A (en) * | 2019-01-31 | 2019-05-10 | 华中科技大学 | A kind of solid state laser thermal lens focal length method and device |
| CN113557463A (en) * | 2019-03-08 | 2021-10-26 | Pcms控股公司 | Optical method and system for display based on light beam with extended focal depth |
| CN110471144A (en) * | 2019-08-07 | 2019-11-19 | 北京工业大学 | A kind of myriawatt grade optical fiber connector of anaberration |
| CN114924411A (en) * | 2022-05-30 | 2022-08-19 | 中国人民解放军国防科技大学 | Light beam transformation system design method for medium and long distance laser Doppler velocimeter |
| CN116698362A (en) * | 2023-02-23 | 2023-09-05 | 武汉华日精密激光股份有限公司 | Method and device for measuring focal length of end-pumped laser crystal thermal lens |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108288814A (en) | A kind of method and apparatus for the focal length and spherical aberration obtaining laser crystal thermal lens | |
| Chen et al. | Generation of Hermite-Gaussian modes in fiber-coupled laser-diode end-pumped lasers | |
| JP6846525B2 (en) | 183nm CW laser and inspection system | |
| CN1804711B (en) | Device for improving beam quality of solid laser by using intracavity adaptive optical technology | |
| CN101666706B (en) | Device for measuring thermal lens focal length of end-pumped solid-state laser and method | |
| CN105973573B (en) | The measuring method of all solid state laser intracavitary linear impairments | |
| Pan et al. | Real-time complex amplitude reconstruction method for beam quality M 2 factor measurement | |
| CN104729717A (en) | Device and method for measuring and calculating temperature of solid laser crystal | |
| CN102175429A (en) | Method for measuring thermal focus length of laser | |
| CN112345209B (en) | End-pumped laser crystal thermal focus measuring device and method | |
| Perchermeier et al. | Precise measurements of the thermo-optical aberrations of an Yb: YAG thin-disk laser | |
| CN105954010A (en) | Measurement method of nonlinear crystal thermal lens focal length | |
| CN110895239B (en) | Device and method for measuring excited state absorption heat load in laser gain crystal | |
| Yin et al. | Evaluation of the communication quality of free-space laser communication based on the power-in-the-bucket method | |
| Yao et al. | Beam quality improvement by controlling thermal lens spherical aberration in an end-pumped Nd: YVO 4 laser | |
| Sheng et al. | Ultra‐High‐Order Laguerre–Gaussian Field Generated Directly From a Laser Cavity with Spherical Aberration | |
| CN110865053B (en) | Device and method for measuring energy transmission up-conversion heat transfer load in laser gain crystal | |
| Seidel et al. | Influence of disk aberrations on high-power thin-disk laser cavities | |
| Ning et al. | Collimation of laser diode beams for free space optical communications | |
| CN114509242B (en) | Method and device for measuring focal length of laser crystal thermal lens | |
| Liu et al. | Research on the adjusting technology of the thin disk laser | |
| CN114518218B (en) | Method and device for measuring loss in cavity of solid laser | |
| CN116698362A (en) | Method and device for measuring focal length of end-pumped laser crystal thermal lens | |
| CN109239947A (en) | A kind of device and method obtaining hollow beam based on thermo-optic effect | |
| CN205483490U (en) | Debugging of side pumping nd:YAG crystal laser and analysis new installation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20180717 |
|
| WD01 | Invention patent application deemed withdrawn after publication |