下面这个函数大家都不会陌生,计算zernike函数值的,并根据此可以还原出图像来, {r].SrW9s9
我输入10阶的n、m,r,theta为38025*1向量,最后得到的z是29525*10阶的矩阵, O{B
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这个,跟我们用zygo干涉仪直接拟合出的36项zernike系数,有何关系呢? :Hf0Qx6
那些系数是通过对29525*10阶的矩阵每列的值算出来的嘛? <h@z=ijN
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function z = zernfun(n,m,r,theta,nflag) o1#:j?sN
%ZERNFUN Zernike functions of order N and frequency M on the unit circle. E &];>3C
% Z = ZERNFUN(N,M,R,THETA) returns the Zernike functions of order N /J[H5uA
% and angular frequency M, evaluated at positions (R,THETA) on the E/dO7I`B
% unit circle. N is a vector of positive integers (including 0), and gP%|:"
% M is a vector with the same number of elements as N. Each element L*UV
% k of M must be a positive integer, with possible values M(k) = -N(k) U7]<U-.&
% to +N(k) in steps of 2. R is a vector of numbers between 0 and 1, S[L#M;n
% and THETA is a vector of angles. R and THETA must have the same I NPYJ#%
% length. The output Z is a matrix with one column for every (N,M) 2GiUPtO&Gj
% pair, and one row for every (R,THETA) pair. &'huS?gA9
% 9b" 9m*gC
% Z = ZERNFUN(N,M,R,THETA,'norm') returns the normalized Zernike S7UZGGjTk
% functions. The normalization factor sqrt((2-delta(m,0))*(n+1)/pi), 62MRI
% with delta(m,0) the Kronecker delta, is chosen so that the integral YH'$_,8peM
% of (r * [Znm(r,theta)]^2) over the unit circle (from r=0 to r=1, mZbWRqP[|_
% and theta=0 to theta=2*pi) is unity. For the non-normalized `\/toddUh[
% polynomials, max(Znm(r=1,theta))=1 for all [n,m]. P>{US1t
% J+}+"h~.
% The Zernike functions are an orthogonal basis on the unit circle. Z@uTkqG)
% They are used in disciplines such as astronomy, optics, and >k&8el6h
% optometry to describe functions on a circular domain. UK"}}nO@e
% Zp7yaz3y
% The following table lists the first 15 Zernike functions. a@fE46o6<
% *?^Z)C>
% n m Zernike function Normalization 3C rQBIj1
% -------------------------------------------------- Wa[x`:cT?u
% 0 0 1 1 S]e j=6SP
% 1 1 r * cos(theta) 2 +9CEC1-l
% 1 -1 r * sin(theta) 2 B]^>GH
% 2 -2 r^2 * cos(2*theta) sqrt(6) 4?>18%7&
% 2 0 (2*r^2 - 1) sqrt(3) XOysgX0g
% 2 2 r^2 * sin(2*theta) sqrt(6) * MSBjH|
% 3 -3 r^3 * cos(3*theta) sqrt(8) 9^ >M>f"
% 3 -1 (3*r^3 - 2*r) * cos(theta) sqrt(8) ]g;^w?9h
% 3 1 (3*r^3 - 2*r) * sin(theta) sqrt(8) Sc1+(z
% 3 3 r^3 * sin(3*theta) sqrt(8) :W.jNV{e\F
% 4 -4 r^4 * cos(4*theta) sqrt(10) {J,6iP{>ZN
% 4 -2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) -,~;qSs
% 4 0 6*r^4 - 6*r^2 + 1 sqrt(5) f{y]
% 4 2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) <`R|a *
% 4 4 r^4 * sin(4*theta) sqrt(10) 2PVx++*]C
% -------------------------------------------------- |'V DI]p&
%
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% Example 1: E /fw?7eQ
% ]ZzoJ7lr
% % Display the Zernike function Z(n=5,m=1) ^Yj"RM$;N
% x = -1:0.01:1; K-J|/eB
% [X,Y] = meshgrid(x,x); ="uKWt6n'
% [theta,r] = cart2pol(X,Y); _\
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% idx = r<=1; cS<TmS!
% z = nan(size(X)); V#ndyUM;
% z(idx) = zernfun(5,1,r(idx),theta(idx)); PUbaS{J7
% figure X}oj_zsy;^
% pcolor(x,x,z), shading interp 7"ylN"syZ
% axis square, colorbar iD>G!\&