CN109613698A - A kind of design method of metal film hyperoscillating annulus piece - Google Patents
A kind of design method of metal film hyperoscillating annulus piece Download PDFInfo
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Abstract
The invention discloses a kind of design methods of metal film hyperoscillating annulus piece, belong to micronano optical and nanophotonics technical field.The concentric zonary structure of metal film of this method based on unequal width uses the diffractive light field in any distance perpendicular plane after vector angular spectra theory and Fast Hankel Transform algorithm calculating hyperoscillating annulus piece under the conditions of laser beam vertical illumination;Set diameter, annulus number, focal length and the minimum ring bandwidth of hyperoscillating annulus piece;Establish the optimization object function of single focus or laser accunputure focus issues;Annulus width and its transmitance are optimized using genetic algorithm, obtain the hyperoscillating annulus chip architecture for meeting design object.The present invention is relative to existing hyperoscillating annulus design method, due to the zonary structure based on unequal width, and minimum ring bandwidth can be limited according to existing processing technology, it include a small amount of light penetrating ring band, the metal film hyperoscillating annulus piece with more dominance energy so as to design.
Description
Technical field
The invention belongs to micronano optical and nanophotonics technical field, in particular to a kind of metal film hyperoscillating annulus piece
Design method.
Background technique
Hyperoscillating (Superoscillation) has mathematically carried out full theoretical description first, refers to a frequency domain band
Function or its Local oscillating frequency of signal a kind of phenomenon faster than the cutoff frequency of entire function are limited, optics hyperoscillating is utilized
Super-resolution focus may be implemented in (Optical Superoscillation), nearly ten years, realize optics sub-wavelength focus and
In terms of super-resolution imaging, this method is had received widespread attention, and essence is not depend near field evanescent wave in far-field optics scope
Contribution, utilize far field transmission field coherent superposition generate super-resolution focus.
2009, a kind of special continuous amplitude transmittance function of Southampton, Britain university theory building, however use
The mask plate of continuous complex amplitude transmittance function description, it is desirable that very harsh coating process and lithographic process technologies, to existing
There are micro Process and advanced coating process to propose high requirement;2012, University of Southampton proposed significant improvement, proposed
Hyperoscillating lens (Super-oscillatory Lens, SOL), are the polycyclic banding pattern micro-structure diffraction optics of a kind of binary amplitude
Element, referred to herein as metal film hyperoscillating annulus piece.
Southampton, Britain university research personnel are based on wide annulus to the design concept of metal film hyperoscillating annulus piece
Width basic assumption (referring to document E.T.F.Rogers, J.Lindberg, T.Roy, S.Savo, J.E.Chad,
M.R.Dennis,N.I.Zheludev.A super-oscillatorylens optical microscope for
Subwavelength imaging.Nature Materials, 2012,11 (5), 432-435), and use Particle Swarm Optimization
The design of method progress annulus piece;Along this wide annulus basic assumption, 2013, Harbin Institute of Technology researcher was proposed
Using genetic algorithm and vector angular spectra theory carry out metal film hyperoscillating annulus piece design (referring to document T.Liu, J.Tan,
J.Liu,H.Wang.Vectorial design of super-oscillatory lens.Optics Express,2013,
21(13):15090-15101);2017, Northwestern Polytechnical University researcher was based on same it is assumed that having using optimization algorithm
Effect sub-wavelength multifocal is devised (referring to document M.Li, W.Li, H.Li, Y.Zhu, Y.Yu.Controllable design
of super-oscillatory lenses with multiple sub-diffraction-limit
foci.Scientific Reports,2017,7:1335);Domestic Chinese Academy of Sciences's photoelectric technology research institute, University Of Chongqing, Nanjing are big
Xue Deng research institution is based on wide annulus and assumes that basis conducts extensive research, and achieves impressive progress.
The design method of hyperoscillating annulus piece based on wide annulus is simple with design, it is clear to illustrate, it is flexible to modulate
The advantages that, and result usually contains large number of zonary structure, and the radius of annulus is selectively small, causes flat in given observation
Issuable distribution of light intensity distribution character is limited in face.It is tired that above-mentioned technical problem is that the design of current hyperoscillating annulus piece faces
Difficulty, urgent need propose a kind of design method for designing the more flexible higher hyperoscillating annulus piece of freedom degree.
A kind of prior art (national inventing patent: Chen Gang, middle benefit gas spring, Wu Zhixiang, Yu Anping, multivalue phase-two-value amplitude
The hollow ring of light focus device of super diffraction, number of patent application 201610599066.6, July 27 2016 date of application;Chen Gang,
Wu Zhixiang, middle benefit gas spring, Zhang Zhihai, deck-molding peak, a kind of hollow focal spot flat focus device of the super diffraction three-dimensional in far field, number of patent application
201810220342.2, date of application 2018.03.16) designed by focus device continue to use the basic assumption of wide annulus, belong to
The technical method scope of traditional hyperoscillating annulus piece, therefore be directly derived from the design method that not wide annulus is assumed with the present invention and have
There is the significant difference of essence.
Summary of the invention
The purpose of the present invention is to provide a kind of more flexible, the higher amplitude type metal film hyperoscillating of optimization efficiency of design
The design method of annulus piece can be designed under the conditions of laser beam vertical illumination by specified parameter and a small amount of light penetrating ring band
The hyperoscillating annulus piece of more dominance energy out.
The present invention adopts the following technical scheme that realize:
A kind of design method of metal film hyperoscillating annulus piece, metal film concentric ring band knot of this method based on unequal width
Structure calculates hyperoscillating ring using vector angular spectra theory and Fast Hankel Transform algorithm under the conditions of laser beam vertical illumination
Diffractive light field after strap in any distance perpendicular plane;Set diameter, annulus number, focal length and the minimum of hyperoscillating annulus piece
Annulus width;Establish the optimization object function of single focus or laser accunputure focus issues;Using genetic algorithm to annulus width and its thoroughly
The rate of mistake optimizes, and is approached or met the hyperoscillating annulus chip architecture of design object.
A further improvement of the present invention lies in that the metal film hyperoscillating annulus piece is the binary amplitude type of plating metal on surface film
Hyperoscillating annulus piece changes each annulus by etching surface metal film to the transmitance of incident laser beam;Wherein transmitance
It indicates to be blocked by the laser beam in the ring belt area by metal film for 0, i.e., the annulus is opaque;Transmitance is that 1 expression should
Metal membrane-coating etching in ring belt area, laser beam can pass through, i.e. the annulus light transmission.
A further improvement of the present invention lies in that this method specifically comprises the following steps:
Step 1 gives required hyperoscillating annulus piece diffractive light field intensity distribution feature, and according to required diffraction light
Field intensity distribution, is respectively laterally and axially constraining diffracted intensity field, is establishing optimization object function and constraint condition;
Step 2 sets hyperoscillating according to the requirement of hyperoscillating annulus piece and existing micro-nano technology process conditions
Diameter D, focal length f, annulus number N and the minimum ring bandwidth Δ r of annulus pieceminPhysical characteristic parameter, the wavelength of laser illuminator light beam
λ0, working media locating for polarization state and hyperoscillating annulus piece refractive index nwOperating condition parameters;
Step 3 is calculated under the parameter setting of step 2 by vector angular spectra theory and Fast Hankel Transform algorithm
Distribution of light intensity distribution after hyperoscillating annulus piece in any distance perpendicular plane;
Step 4 is solved using genetic algorithm on the basis of hyperoscillating annulus piece not equal annulus width and meets optimization mesh
Target hyperoscillating annulus chip architecture.
A further improvement of the present invention lies in that in step 1, hyperoscillating annulus piece diffractive light field intensity distribution feature, packet
It includes: the lateral full width at half maximum of focal beam spot, axial full width at half maximum, or focus the lateral full width at half maximum, axial depth of focus and axis of laser accunputure
To light intensity uniformity.
A further improvement of the present invention lies in that establishing optimization object function in step 1 method particularly includes:
According to the full width at half maximum and depth of focus of required focal beam spot or laser accunputure, laterally and axially focal beam spot is found respectively
Or the half height point of laser accunputure, and seek light intensity and focal beam spot or the ratio F of laser accunputure center light intensity at half height point positionxyWith
Fz, which is the laterally and axially optimization object function respectively established;Optimization object function in both direction passes through
The weighting coefficient w of setting1And w2Synthesize a total optimization object function F=w1/Fxy+w2/Fz, make multi-objective optimization question
It is converted into single-object problem, so as to Optimization Solution.
A further improvement of the present invention lies in that the constraint condition of optimization object function is according to hyperoscillating ring in step 1
The practical situations setting of strap, the length in dark field region between the center main lobe including distribution of light intensity and surrounding high-order secondary lobe
Degree, the largest light intensity in dark field region, the axial uniformity of focusing laser accunputure.
A further improvement of the present invention lies in that in step 2, specific sets requirement are as follows: the diameter D of hyperoscillating annulus piece
≥5λ0, λ0It is laser illuminator wavelength, it is desirable that λ0>=10nm covers X-ray;Focal length f is not less than illumination wavelengths λ0, annulus number N >=
2, minimum ring bandwidth Δ rmin≥200nm;The polarization state of laser illuminator light beam is linear polarization, circular polarization or radial polarisation, work
Medium is air, oil or water.
A further improvement of the present invention lies in that vector angular spectra theory refers to that first passing around a Fourier becomes in step 3
The angular spectrum for getting micro-structure rear surface optical output field in return obtains each polarized component of light field using an inverse Fourier transform,
When to which laser beam illumination micro-structure is calculated, the distribution of light intensity distribution in any distance perpendicular plane thereafter;And root
According to the difference of incident laser optical polarization, derive accordingly in perpendicular plane at diffraction screen rear surface any distance
Electric field polarization component calculation formula.
A further improvement of the present invention lies in that Fast Hankel Transform algorithm refers to that you become in standard Hunk in step 3
It changes in integral expression, carries out variable replacement using nonlinear exponent function, the unilateral Hankel transform of standard is expressed as bilateral
Cross-correlation integral, to realize a kind of fast and accurately calculation method for calculating cross-correlation using Fourier transformation.
A further improvement of the present invention lies in that in step 4, the detailed process of Genetic Algorithm optimized design are as follows:
401) it performs the encoding operation: annulus width and its transmitance being encoded respectively, wherein the width of N number of annulus is logical
The N-1 cut-point generated at random in the section [0, R] crossed between 0 to hyperoscillating annulus piece radius R obtains, the position of cut-point
Set equally distributed random decimal number coding in use [0, R] section;Annulus transmitance uses binary coding, and 0 represents ring
With opaque, 1 represents annulus light transmission;
402) p is generated at randomsA initial individuals form initial population, and whether judgement initial individuals first meet minimum ring band
New individual is rejected and generated at random again to width requirement for the individual for being unsatisfactory for requiring, until institute in initial population
Until thering is individual to be all satisfied requirement;Then the optimization mesh of each individual is calculated according to the optimization object function established in step 1
Offer of tender numerical value Fi, i=1,2 ..., ps;
403) constraint condition in Optimized model certain optimization object function is written as raising optimization efficiency to be incorporated to
Into total objective function, requirement to dark field region by seek the largest light intensity in dark field region and main lobe central light strength it
Than as objective function Fd, and be merged into total objective function F with the weighting coefficient of setting, i.e. F=w1/Fxy+w2/Fz+
w3/Fd;
404) selection duplication operation: the side that selection strategy uses elite individual retention strategy to combine with roulette is carried out
The highest individual of fitness in population is copied directly to the next generation without intersection and mutation operation first by method;Remaining
Body is selected according to wheel disc bet method, implementation method are as follows: is determined first according to all respective fitness values of individual respective
Select probabilityThen a random number r is randomly generated in [0,1] section, ifThen select
It selects individual i and copies to the next generation, wherein P0=0;
405) according to crossover probability Pc, a random number r is generated at random for every two individual, if r≤Pc, then this two
Individual carries out crossover operation;Crossover operation uses uniform crossover method, is first randomly generated one and parent individuality chromosome
The identical binary system crossover template of code length, 0 in template represents and does not do to two individual corresponding positions for participating in intersecting
Exchange, 1 representative execute exchange to corresponding position;Judge whether the new individual generated meets after the completion of every a pair of individual intersection operation
The requirement of minimum ring bandwidth, if the requirements are not met then re-starts crossover operation;
406) according to mutation probability Pm, a random number r is generated at random for each individual, if r≤Pm, then the individual
Carry out mutation operation;Mutation operation is made a variation using single-point, if generate variation is the cut-point of decision ring bandwidth, is taken
Equally distributed random number is replaced in [0, R] section;If generate variation is annulus transmitance, to annulus transmitance
It is negated, i.e., light transmission 1, which becomes opaque 0, opaque 0, becomes light transmission 1;Judgement generates after the completion of each individual variation operation
Whether new individual meets the requirement of minimum ring bandwidth, and if the requirements are not met then re-starts mutation operation;
407) new progeny population is generated after the completion of selecting, intersect and making a variation, calculates the target of all individuals of progeny population
Functional value is replaced original parent population with new progeny population, and returns to the step 404) of genetic algorithm, carries out a new round
Iteration, repeatedly until reaching the number of iterations N of settingg;
408) the number of iterations N is completedgAfterwards, genetic optimization process terminates, and final optimum results are NgFor being adapted in population
Spend highest individual, i.e., required hyperoscillating annulus piece surface loop band knot that is close or meeting setting diffractive light field intensity distribution
Structure.
The present invention has following beneficial technical effect:
A kind of design method of metal film hyperoscillating annulus piece provided by the invention, metal of this method based on unequal width
The concentric zonary structure of film uses vector angular spectra theory and quick Hunk under the conditions of typical polarization state laser beam vertical illumination
Diffractive light field after your transformation algorithm calculating hyperoscillating annulus piece at any distance position;Set the straight of hyperoscillating annulus piece
Diameter, annulus number, focal length and minimum ring bandwidth;Establish the Optimized model and objective function of single focus or laser accunputure focus issues;It adopts
With and configure genetic algorithm each annulus width and its transmitance optimized, obtain the hyperoscillating annulus piece for meeting design object
Structure.The present invention is relative to existing hyperoscillating annulus design method, due to the zonary structure based on unequal width, and can root
Minimum ring bandwidth is limited according to existing processing technology, includes a small amount of light penetrating ring band, with more dominance energy so as to design
Metal film hyperoscillating annulus piece.This method is suitable for a variety of typical polarization laser beam illumination situations, and designed metal film is super
Oscillation rings strap is suitable for the fields such as far field high-resolution micro-imaging, nano-photoetching, optical control, laser direct-writing.
Therefore, the present invention has the advantages that design is more flexible, optimization efficiency is higher, and in typical polarization state laser beam
Under the conditions of vertical illumination, by specifying parameter and a small amount of light penetrating ring band that the hyperoscillating annulus of excellent focusing effect can be realized
Piece.
Detailed description of the invention
Fig. 1 is the surface loop band micro-structure schematic diagram of metal film hyperoscillating annulus piece in the present invention.
Fig. 2 is the flow chart of heretofore described genetic algorithm.
Fig. 3 is the transmittance function figure of hyperoscillating annulus piece in the specific embodiment of the invention.
Fig. 4 is the vector angular spectrum reason that hyperoscillating annulus piece focal plane y is distributed to distribution of light intensity in the specific embodiment of the invention
Calculate by (Vectorial Angular Spectrum, VAS) design result and stringent Electromagnetic Simulation (Finite-Difference Time-Domain Method,
FDTD) comparative result figure.
Fig. 5 is the vector angular spectrum reason that z is distributed to distribution of light intensity on hyperoscillating annulus piece optical axis in the specific embodiment of the invention
By design result and the stringent Electromagnetic Simulation calculated result comparison diagram of FDTD.
Fig. 6 is in the specific embodiment of the invention, and the stringent Electromagnetic Simulation of the FDTD of hyperoscillating annulus piece focal plane calculates intensity
Distribution map.
Fig. 7 is in the specific embodiment of the invention, and the stringent Electromagnetic Simulation of the FDTD of hyperoscillating annulus piece axial direction X-Z plane calculates
Intensity distribution.
Fig. 8 is in the specific embodiment of the invention, and the stringent Electromagnetic Simulation of the FDTD of hyperoscillating annulus piece axial direction Y-Z plane calculates
Intensity distribution.
Specific embodiment
The embodiment that the present invention will be described in detail with reference to the accompanying drawings and examples.
The present embodiment is illustrated so that hyperoscillating annulus piece generates focal beam spot as an example.Using hyperoscillating as shown in Figure 1
Annulus piece is modulated incident diffractive light field, is generating focal beam spot in hyperoscillating annulus piece rear surface specific region,
Light propagation analysis is carried out using vector angular spectra theory;On the basis ofs hyperoscillating annulus loop bandwidth is not equal, heredity is utilized
Algorithm solves the hyperoscillating annulus chip architecture for meeting optimization aim.
(1) vector angular spectra theory light field calculates
Assuming that the linearly polarized light vibrated along the x axis is along Z axis forward-propagating, the micro- knot in vertical illumination hyperoscillating annulus piece surface
Structure, after micro-structure annulus diffraction, according to vector angular spectra theory, any point position in the perpendicular plane of z > 0
Place electric field E orthogonal components be
In formula, Ex(r, z) indicates x to component, Ey(r, z) indicate y to component,Indicate z to component, q (l)=
(1/λ2-l2)1/2, l indicates that radial spatial frequency component, r indicate that any point P is relative to the plane and optical axis in perpendicular plane
The distance of intersection point,Indicate angle of the P point relative to X-axis forward direction, the axial position of perpendicular plane where z indicates P point;J0And J1
It is first kind zero and first order Bessel function respectively, j is imaginary unit;Space angular spectrum A0(l) it indicates are as follows:
In formula, t (r) indicates the corresponding amplitude transmittance function of any round Symmetry Microstructure;G (r) indicates that illuminating bundle exists
Optical field amplitude in micro-structure annulus plate plane, it is assumed here that uniform plane wave illumination, corresponding g (r)=1.It can be obtained by formula (1)
Distribution of light intensity is distributed as after to hyperoscillating annulus piece
When laser illuminator light beam is Left-hand circular polarization light, each component of electric field E is
In formula, A0(l) it is provided by formula (2).Can equally obtain, after hyperoscillating annulus piece distribution of light intensity be distributed as I (r, z)=
2|Ex(r,z)|2+|Ez(r,z)|2。
When can calculate separately to obtain linearly polarized light and circularly polarized light illumination hyperoscillating annulus piece according to formula (1)~formula (3)
Thereafter the optical field distribution in any perpendicular plane, can also similarly calculate the distribution of light field under radial polarisation light illumination situations.
(2) Fast Hankel Transform algorithm
In formula (1)~formula (3) calculating process, need to be performed a plurality of times zero and first order Hankel transform, therefore Hunk
The computational efficiency and precision of your transformation are the key that design methods, and in order to accelerate operation, programming realizes that a kind of quick Hunk that becomes
Scaling method (referring to document A.E.Siegman.Quasi Fast Hankel Transform.Optics Letters, 1977,1:
13-15), which has a remarkable advantages such as calculating speed is fast, precision is high, extremely low computer memory requirement, basic principle be
In standard Hankel transform integral expression, replaced using nonlinear exponent function variable, by the unilateral Hankel transform table of standard
It is shown as bilateral cross-correlation integral, Fourier transformation is can use after such transformation and calculates cross-correlation.
(3) specific embodiment
Now the diffractive light field intensity distribution of hyperoscillating annulus piece is required to focus for axial single focus: the transverse direction of focal beam spot
Full width at half maximum FWHMxy=0.4 λ0, longitudinal depth of focus DOF=λ0。
Using wavelength X0The X-direction linearly polarized laser beam orthogonal of=633nm illuminates, and working media is air (refractive index nw
=1) f=4 μm of D=20 μm of diameter, focal length, annulus number N=20, the minimum ring bandwidth Δ r of hyperoscillating annulus piece, are designedmin=
200nm;
The Optimized model of foundation is as follows:
Wherein, FWHMxyIt is diffractive light field transverse direction full width at half maximum, f is focal length, tiIt is the transmitance of each annulus, wherein i is indicated
The number of each annulus of hyperoscillating annulus piece, by internal outside successively value i=1,2 ..., N, I (FWHMxy/ 2, f, ti) indicate horizontal
Distribution of light intensity at light field full width at half maximum, I (0, f, ti) be lateral light field focal beam spot center distribution of light intensity;I(0,
f-,ti) and I (0, f+,ti) it is that light field main lobe or so two full width at half maximum point f are focused on Z-direction axis respectively-And f+Distribution of light intensity.
In order to enable the hyperoscillating annulus piece designed, which can be used in high-resolution, focuses scanning imagery, need to make center master
Valve and surrounding high-order secondary lobe are separated by a sufficiently wide dark field region, therefore make following constraint to diffractive light field:
The dark field region value range of transverse focusing light field is to arrive apart from the main lobe center high overall with of half as much again in formula (5)
Three times full width at half maximum region, it is ensured that the high-order secondary lobe light field of main lobe light field and surrounding is sufficiently separated;Since design requirement is axial
Single focus focuses, therefore to remaining area other than the depth of focus DOF distance of axial focusing hot spot two sides distance focal point center one
The distribution of light intensity in domain is constrained.
Under the conditions of above-mentioned optimization object function and constraint, it is as follows to establish the total optimization object function of genetic algorithm:
Fitness=w1/Fxy+w2/Fz+w3/Fd,xy+w4/Fd,z (6)
Wherein,WithIt is the optimization object function being transformed by constraint condition;
Each optimization object function weight coefficient takes w1=w2=0.85, w3=w4=0.15;Original, which solves, realizes setting distribution of light intensity distribution
The maximum value that hyperoscillating annulus piece optimization structure problem is converted into solving optimization objective function Fitness (or fitness function) is asked
Topic.
The individual chromosome coding strategy of genetic algorithm are as follows: each individual N chromosome codings in total, preceding N-1 dyeing
Body decimal coded, indicates the cut-point position for determining each annulus width, and value range is [0, R];Last chromosome two
Scale coding determines the transmitance of hyperoscillating annulus piece, indicates that hyperoscillating annulus piece central belt is impermeable if last position is 0
Light, the transmitance of the individual ownership annulus are 0,1,0,1,0,1 ...;It is indicated in hyperoscillating annulus piece if last position is 1
Thimble band light transmission, the transmitance of the individual ownership annulus are 1,0,1,0,1,0....The genetic algorithm optimization parameter of setting are as follows: just
The number of individuals ps=60 of beginning population, the total degree N of genetic manipulation iterationg=100;Heredity selection duplication is retained using elite individual
The method that strategy is combined with roulette;Crossover operation uses uniform crossover method, crossover probability Pc=0.8;Mutation operation is real
Row single-point genetic mutation, mutation probability Pm=0.08.
According to the above Parameter Programming realize genetic algorithm, the zonary structure for the hyperoscillating annulus piece that Optimization Solution obtains and thoroughly
Cross that rate is as shown in table 1, the geometrical structure parameter and focus characteristics of hyperoscillating annulus piece are as shown in table 2.Wherein NiIt is annulus number,
Number is 1 to 20 from inside to outside, Δ riAnd tiIt is the width and its transmitance of each annulus, N respectivelytIt is light penetrating ring band number;Utilize half
High overall with value indicates the breadth wise dimension of focal beam spot, the axial dimension of focal beam spot is indicated using depth of focus, specific value is equal
It is indicated with the multiple of laser wavelength of incidence.
The annulus width and its transmitance of 1 hyperoscillating annulus piece of table
The surface zonary structure parameter and focus characteristics of 2 hyperoscillating annulus piece of table
Known to Tables 1 and 2: the minimum ring bandwidth of design result is 221nm, requires Δ greater than given minimum annular ring
rmin=200nm, meets the requirements;Design gained hyperoscillating annulus piece only includes 10 light penetrating ring bands, the corresponding numerical aperture of annulus piece
Diameter NA is 0.93, the y-axis direction minimum full width at half maximum FWHM of focal plane focal beam spoty=0.496 λ0≤0.5λ0, realize sub- wave
It is long to focus;Axial depth of focus has also reached 1.485 λ0;The full width at half maximum in lateral x-axis direction and y-axis direction is unequal, focal beam spot
In dumbbell shape, this is the basic focus characteristics of linearly polarized light incidence under the conditions of large-numerical aperture.
A kind of focusing hyperoscillating annulus piece provided in the present embodiment, zonary structure schematic diagram such as Fig. 1 of design result
Shown, corresponding annulus transmittance function is as shown in Figure 3;Vector angular spectra theory (VAS) calculated result of the hyperoscillating annulus piece
It coincide substantially with the stringent Electromagnetic Simulation calculated result of FDTD, as shown in Figure 4 and Figure 5, demonstrates a kind of super vibration of metal film of the present invention
Swing the validity of the design method of annulus piece.Fig. 6, Fig. 7 and Fig. 8 are respectively hyperoscillating annulus piece X-Y plane, X-Z plane and Y-Z
The stringent Electromagnetic Simulation of the FDTD of plane calculates intensity distribution.
Three-dimensional FDTD simulation parameters involved in the present embodiment are as follows: use whole audience scattered field (TFSF) light source, wavelength
633nm, boundary condition PML;Hyperoscillating annulus piece substrate uses quartz glass, and surface uses the aluminium film of 100nm thickness;Work
Making environment is air, refractive index 1;FDTD simulating area is x, y:[-11,11], z:[-2,10] (unit is μm);By ring
The laser beam plane of incidence of strap metal film is as datum level (z=0);The size of mesh opening of division is 15nm × 15nm × 15nm.
A specific embodiment of the invention is described in conjunction with attached drawing above, but these explanations cannot be understood to limit
The scope of the present invention, protection scope of the present invention are limited by appended claims, any in the claims in the present invention base
Change on plinth is all protection scope of the present invention.
Claims (10)
1. a kind of design method of metal film hyperoscillating annulus piece, which is characterized in that metal film of this method based on unequal width
Concentric zonary structure uses vector angular spectra theory and Fast Hankel Transform algorithm meter under the conditions of laser beam vertical illumination
Diffractive light field after calculation hyperoscillating annulus piece in any distance perpendicular plane;Set the diameter of hyperoscillating annulus piece, annulus number,
Focal length and minimum ring bandwidth;Establish the optimization object function of single focus or laser accunputure focus issues;Using genetic algorithm to annulus
Width and its transmitance optimize, and are approached or met the hyperoscillating annulus chip architecture of design object.
2. a kind of design method of metal film hyperoscillating annulus piece according to claim 1, which is characterized in that the metal film
Hyperoscillating annulus piece is the binary amplitude type hyperoscillating annulus piece of plating metal on surface film, is changed by etching surface metal film each
Transmitance of the annulus to incident laser beam;Wherein transmitance is indicated through the laser beam in the ring belt area for 0 by metal
Film blocks, i.e., the annulus is opaque;Transmitance is the metal membrane-coating etching in 1 expression ring belt area, and laser beam can lead to
It crosses, i.e. the annulus light transmission.
3. a kind of design method of metal film hyperoscillating annulus piece according to claim 1 or 2, which is characterized in that the party
Method specifically comprises the following steps:
Step 1 gives required hyperoscillating annulus piece diffractive light field intensity distribution feature, and according to required diffraction light field strength
Degree distribution, is respectively laterally and axially constraining diffracted intensity field, is establishing optimization object function and constraint condition;
Step 2 sets hyperoscillating annulus according to the requirement of hyperoscillating annulus piece and existing micro-nano technology process conditions
Diameter D, focal length f, annulus number N and the minimum ring bandwidth Δ r of pieceminPhysical characteristic parameter, the wavelength X of laser illuminator light beam0、
The refractive index n of working media locating for polarization state and hyperoscillating annulus piecewOperating condition parameters;
Step 3 calculates super vibration by vector angular spectra theory and Fast Hankel Transform algorithm under the parameter setting of step 2
Swing the distribution of light intensity distribution after annulus piece in any distance perpendicular plane;
Step 4 meets optimization aim using genetic algorithm solution on the basis of hyperoscillating annulus piece not equal annulus width
Hyperoscillating annulus chip architecture.
4. a kind of design method of metal film hyperoscillating annulus piece according to claim 3, which is characterized in that step 1
In, hyperoscillating annulus piece diffractive light field intensity distribution feature, comprising: the lateral full width at half maximum of focal beam spot, axial full width at half maximum,
Or focus the lateral full width at half maximum, axial depth of focus and axial intensity uniformity of laser accunputure.
5. a kind of design method of metal film hyperoscillating annulus piece according to claim 3 or 4, which is characterized in that step
In one, optimization object function is established method particularly includes:
According to the full width at half maximum and depth of focus of required focal beam spot or laser accunputure, laterally and axially focal beam spot or light are found respectively
The half height point of needle, and seek light intensity and focal beam spot or the ratio F of laser accunputure center light intensity at half height point positionxyAnd Fz, should
Ratio is the laterally and axially optimization object function respectively established;Optimization object function in both direction passes through setting
Weighting coefficient w1And w2Synthesize a total optimization object function F=w1/Fxy+w2/Fz, it is converted into multi-objective optimization question
Single-object problem, so as to Optimization Solution.
6. a kind of design method of metal film hyperoscillating annulus piece according to claim 3, which is characterized in that step 1
In, the constraint condition of optimization object function is set according to the practical situations of hyperoscillating annulus piece, including distribution of light intensity
Center main lobe and surrounding high-order secondary lobe between the length in dark field region, the largest light intensity in dark field region, the axial direction for focusing laser accunputure
Uniformity.
7. a kind of design method of metal film hyperoscillating annulus piece according to claim 5, which is characterized in that step 2
In, specific sets requirement are as follows: the λ of diameter D >=5 of hyperoscillating annulus piece0, λ0It is laser illuminator wavelength, it is desirable that λ0>=10nm, covers
Lid X-ray;Focal length f is not less than illumination wavelengths λ0, annulus number N >=2, minimum ring bandwidth Δ rmin≥200nm;Laser illuminator light
The polarization state of beam is linear polarization, circular polarization or radial polarisation, and working media is air, oil or water.
8. a kind of design method of metal film hyperoscillating annulus piece according to claim 3, which is characterized in that step 3
In, vector angular spectra theory refers to that first passing around a Fourier transformation obtains the angular spectrum of micro-structure rear surface optical output field, then passes through
It crosses an inverse Fourier transform and obtains each polarized component of light field, thus when laser beam illumination micro-structure is calculated, thereafter
Distribution of light intensity distribution in any distance perpendicular plane;And according to the difference of incident laser optical polarization, derive corresponding
The electric field polarization component calculation formula in perpendicular plane at diffraction screen rear surface any distance.
9. a kind of design method of metal film hyperoscillating annulus piece according to claim 7, which is characterized in that step 3
In, Fast Hankel Transform algorithm refers in standard Hankel transform integral expression, is carried out using nonlinear exponent function
The unilateral Hankel transform of standard is expressed as bilateral cross-correlation integral, is calculated to realize using Fourier transformation by variable replacement
A kind of fast and accurately calculation method of cross-correlation.
10. a kind of design method of metal film hyperoscillating annulus piece according to claim 9, which is characterized in that step 4
In, the detailed process of Genetic Algorithm optimized design are as follows:
401) perform the encoding operation: annulus width and its transmitance being encoded respectively, wherein the width of N number of annulus by
The N-1 cut-point generated at random in section [0, R] between 0 to hyperoscillating annulus piece radius R obtains, and the position of cut-point is adopted
With random decimal number coding equally distributed in [0, R] section;Annulus transmitance uses binary coding, and 0 represents annulus not
Light transmission, 1 represents annulus light transmission;
402) p is generated at randomsA initial individuals form initial population, and whether judgement initial individuals first meet minimum ring bandwidth
It is required that new individual is rejected and is generated at random again for the individual for being unsatisfactory for requiring, until all in initial population
Until body is all satisfied requirement;Then the optimization aim letter of each individual is calculated according to the optimization object function established in step 1
Numerical value Fi, i=1,2 ..., ps;
403) constraint condition in Optimized model certain optimization object function is written as raising optimization efficiency to be incorporated into always
Objective function in, requirement to dark field region is by seeking being compared to for the largest light intensity in dark field region and main lobe central light strength
For objective function Fd, and be merged into total objective function F with the weighting coefficient of setting, i.e. F=w1/Fxy+w2/Fz+w3/Fd;
404) selection duplication operation: the method that selection strategy uses elite individual retention strategy to combine with roulette is carried out, it is first
The highest individual of fitness in population is first copied directly to the next generation without intersection and mutation operation;Remaining individual basis
Wheel disc bet method is selected, implementation method are as follows: determines that respective selection is general according to all respective fitness values of individual first
RateThen a random number r is randomly generated in [0,1] section, ifThen select individual
I copies to the next generation, wherein P0=0;
405) according to crossover probability Pc, a random number r is generated at random for every two individual, if r≤Pc, then the two are a
Body carries out crossover operation;Crossover operation uses uniform crossover method, is first randomly generated one and parent individuality chromosome coding
The identical binary system crossover template of length, 0 in template represents and does not exchange two individual corresponding positions for participating in intersecting,
1 representative executes exchange to corresponding position;Judge whether the new individual generated meets minimum after the completion of every a pair of individual intersection operation
Annulus width requirement, if the requirements are not met then re-starts crossover operation;
406) according to mutation probability Pm, a random number r is generated at random for each individual, if r≤Pm, then the individual carries out
Mutation operation;Mutation operation is made a variation using single-point, if generate variation is the cut-point of decision ring bandwidth, takes [0, R]
Equally distributed random number is replaced in section;If generate variation is annulus transmitance, annulus transmitance is carried out
It negates, i.e., light transmission 1, which becomes opaque 0, opaque 0, becomes light transmission 1;Judgement generates after the completion of each individual variation operation new
Whether body meets the requirement of minimum ring bandwidth, and if the requirements are not met then re-starts mutation operation;
407) new progeny population is generated after the completion of selecting, intersect and making a variation, calculates the objective function of all individuals of progeny population
Value is replaced original parent population with new progeny population, and returns to the step 404) of genetic algorithm, is carried out a new round and is changed
Generation, repeatedly until reaching the number of iterations N of settingg;
408) the number of iterations N is completedgAfterwards, genetic optimization process terminates, and final optimum results are NgMost for fitness in population
High individual, i.e., required hyperoscillating annulus piece surface zonary structure that is close or meeting setting diffractive light field intensity distribution.
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
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Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1104338A (en) * | 1994-08-27 | 1995-06-28 | 中国科学院上海光学精密机械研究所 | Multi-wavelength confocal diffraction optical element |
US20060221449A1 (en) * | 2005-01-24 | 2006-10-05 | Glebov Leonid B | Stretching and compression of laser pulses by means of high efficiency volume diffractive gratings with variable periods in photo-thermo-refractive glass |
CN103076646A (en) * | 2013-01-30 | 2013-05-01 | 中国科学院光电技术研究所 | Method for manufacturing nanoscale super-resolution optical focusing device |
CN105629461A (en) * | 2016-01-11 | 2016-06-01 | 西安交通大学 | Hundred nanometer scale ultrafine light needle field focusing |
CN106547091A (en) * | 2017-01-12 | 2017-03-29 | 西安交通大学 | A kind of method that large-numerical aperture Fresnel zone plate is designed by axial resolution |
CN106773030A (en) * | 2016-11-24 | 2017-05-31 | 西安交通大学 | A kind of simple uniform laser accunputure focusing microstructures and method for designing |
-
2019
- 2019-01-03 CN CN201910005119.0A patent/CN109613698B/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1104338A (en) * | 1994-08-27 | 1995-06-28 | 中国科学院上海光学精密机械研究所 | Multi-wavelength confocal diffraction optical element |
US20060221449A1 (en) * | 2005-01-24 | 2006-10-05 | Glebov Leonid B | Stretching and compression of laser pulses by means of high efficiency volume diffractive gratings with variable periods in photo-thermo-refractive glass |
CN103076646A (en) * | 2013-01-30 | 2013-05-01 | 中国科学院光电技术研究所 | Method for manufacturing nanoscale super-resolution optical focusing device |
CN105629461A (en) * | 2016-01-11 | 2016-06-01 | 西安交通大学 | Hundred nanometer scale ultrafine light needle field focusing |
CN106773030A (en) * | 2016-11-24 | 2017-05-31 | 西安交通大学 | A kind of simple uniform laser accunputure focusing microstructures and method for designing |
CN106547091A (en) * | 2017-01-12 | 2017-03-29 | 西安交通大学 | A kind of method that large-numerical aperture Fresnel zone plate is designed by axial resolution |
Non-Patent Citations (1)
Title |
---|
TAO LIU,TONG SHEN,SHUMING YANG AND ZHUANGDE JIANG: "《Subwavelength focusing by binary multi-annular plates:design theory and experiment》", 《JOURNAL OF OPTICS》 * |
Cited By (12)
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CN110361862A (en) * | 2019-07-15 | 2019-10-22 | 暨南大学 | A kind of system and method for eliminating hyperoscillating spot side-lobe |
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CN111221122B (en) * | 2020-03-18 | 2022-02-01 | 长春理工大学 | Design method of super-resolution telescopic imaging system with larger field intensity tolerance |
CN111898266A (en) * | 2020-07-29 | 2020-11-06 | 大连海事大学 | Topological optimization method for high-efficiency transmission metamaterial microstructure with sub-wavelength aperture in any shape |
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