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, l
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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, !'>#!S~h3
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? j\.e6&5%SS
那些系数是通过对29525*10阶的矩阵每列的值算出来的嘛? ~{6}SXp4U
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function z = zernfun(n,m,r,theta,nflag) F<)f&<5E-
%ZERNFUN Zernike functions of order N and frequency M on the unit circle. rPHM_fW(O@
% Z = ZERNFUN(N,M,R,THETA) returns the Zernike functions of order N swhtlc@@
% and angular frequency M, evaluated at positions (R,THETA) on the 4@-Wp]
% unit circle. N is a vector of positive integers (including 0), and (c[DQS j
% M is a vector with the same number of elements as N. Each element kioIyV\=
% k of M must be a positive integer, with possible values M(k) = -N(k) ikPr>
% to +N(k) in steps of 2. R is a vector of numbers between 0 and 1, >.REg[P
% and THETA is a vector of angles. R and THETA must have the same Z,F1n/7
% length. The output Z is a matrix with one column for every (N,M) J!'IkC$>
% pair, and one row for every (R,THETA) pair. FwQGxGZ
% ;47 =x1ji
% Z = ZERNFUN(N,M,R,THETA,'norm') returns the normalized Zernike YIYuqtnSJ
% functions. The normalization factor sqrt((2-delta(m,0))*(n+1)/pi), mNX0BZ
% with delta(m,0) the Kronecker delta, is chosen so that the integral n|PW^kOE/
% of (r * [Znm(r,theta)]^2) over the unit circle (from r=0 to r=1, *`tQX$F
% and theta=0 to theta=2*pi) is unity. For the non-normalized \9}-5
% polynomials, max(Znm(r=1,theta))=1 for all [n,m]. [,|4%Y
% EhN@;D+
% The Zernike functions are an orthogonal basis on the unit circle. ?Y9VviC
% They are used in disciplines such as astronomy, optics, and vNU[ K%U
% optometry to describe functions on a circular domain. &2W`dEv]?
% h:vI:V[/X
% The following table lists the first 15 Zernike functions. ulk yP
% _Aw-{HE'
% n m Zernike function Normalization
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% -------------------------------------------------- JOki4N
% 0 0 1 1 QmsS,Zljo
% 1 1 r * cos(theta) 2 'gk^NAG2^E
% 1 -1 r * sin(theta) 2 e#?rK=C?9
% 2 -2 r^2 * cos(2*theta) sqrt(6) "%=K_WJ?
% 2 0 (2*r^2 - 1) sqrt(3) "+BuFhSLf
% 2 2 r^2 * sin(2*theta) sqrt(6) hrbeTtqi
% 3 -3 r^3 * cos(3*theta) sqrt(8) ]Vf2Mn=]"
% 3 -1 (3*r^3 - 2*r) * cos(theta) sqrt(8) 5eas^Rm
% 3 1 (3*r^3 - 2*r) * sin(theta) sqrt(8)
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% 3 3 r^3 * sin(3*theta) sqrt(8) ]T>YYz
% 4 -4 r^4 * cos(4*theta) sqrt(10) JWQ.Efe
% 4 -2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) Zb~G&.
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% 4 0 6*r^4 - 6*r^2 + 1 sqrt(5) 8noo^QO
% 4 2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) TI3@/SB>
% 4 4 r^4 * sin(4*theta) sqrt(10) t%Y}JKLR
% -------------------------------------------------- Uql7s:!,U
% hQDl&A
% Example 1: e\]CZ5hs3
% E~,Wpl}
% % Display the Zernike function Z(n=5,m=1) jt&rOPL7
% x = -1:0.01:1; o31pF
% [X,Y] = meshgrid(x,x); 8#a2 kR<b
% [theta,r] = cart2pol(X,Y); QWK\6
% idx = r<=1; V j_z"t7q
% z = nan(size(X)); /909ED+)>9
% z(idx) = zernfun(5,1,r(idx),theta(idx)); ~ponYc.Y
% figure @X#e
% pcolor(x,x,z), shading interp lQer|?#
% axis square, colorbar 6XGqZ!2
% title('Zernike function Z_5^1(r,\theta)') {hKf
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% \H.1I=<
% Example 2: i>@"&
% 2aW"t.[j
% % Display the first 10 Zernike functions Qx[
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% x = -1:0.01:1; B_|jDH#RyJ
% [X,Y] = meshgrid(x,x); WR4 \dsgCU
% [theta,r] = cart2pol(X,Y); |", /
% idx = r<=1; 62J-)~_
% z = nan(size(X)); 4031~A8
% n = [0 1 1 2 2 2 3 3 3 3]; 1V 2"sE
% m = [0 -1 1 -2 0 2 -3 -1 1 3]; ;S^7Q5-
% Nplot = [4 10 12 16 18 20 22 24 26 28]; bA3pDt).p
% y = zernfun(n,m,r(idx),theta(idx)); ~ny4Ay$#
% figure('Units','normalized') o2NU~Ub
% for k = 1:10 #5W-*?H
% z(idx) = y(:,k); ]_P!+5]<
% subplot(4,7,Nplot(k)) dK?vg@|'
% pcolor(x,x,z), shading interp q|ww fPez7
% set(gca,'XTick',[],'YTick',[]) m=%WA5c?
% axis square u6u1>
% title(['Z_{' num2str(n(k)) '}^{' num2str(m(k)) '}']) {t<U:*n2
% end 5oE!^bF?
% ]!04L}hy|P
% See also ZERNPOL, ZERNFUN2. \^rAH@
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% Paul Fricker 11/13/2006 A{b?ZT~2]
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% Check and prepare the inputs: dD0:K3@
% ----------------------------- Jri"Toz0
if ( ~any(size(n)==1) ) || ( ~any(size(m)==1) ) Td>Lp=0rU
error('zernfun:NMvectors','N and M must be vectors.') 4zM$I
end .ahYjn
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if length(n)~=length(m) C~dD'Tq]
error('zernfun:NMlength','N and M must be the same length.') }^
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end @.Pe.\Z
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n = n(:); J_^Ml)@iy
m = m(:); Fn~?YN
if any(mod(n-m,2)) DpaPRA)x
error('zernfun:NMmultiplesof2', ... 71ctjU`U2
'All N and M must differ by multiples of 2 (including 0).') K)C9)J<
end 2|n~5\K|t
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if any(m>n) ,#PeK(
error('zernfun:MlessthanN', ... Vg)]F+E
'Each M must be less than or equal to its corresponding N.') JtrLTo
end YI*Av+Z)
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if any( r>1 | r<0 ) mw1|>*X&R
error('zernfun:Rlessthan1','All R must be between 0 and 1.') 45;{tS.z,B
end >}~Pu|
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if ( ~any(size(r)==1) ) || ( ~any(size(theta)==1) ) SDTX3A1
error('zernfun:RTHvector','R and THETA must be vectors.') x;cjl6Acm
end Ol9'ZB|R
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r = r(:); |3?q L
theta = theta(:); SqhG\qE{Qj
length_r = length(r); N!}r(Dd*
if length_r~=length(theta) \?_eQKiZ3
error('zernfun:RTHlength', ... :N<ZO`l?
'The number of R- and THETA-values must be equal.') )h0F'MzW
end %hzl3>().
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lth t'|
% Check normalization: DV(^h$1_
% -------------------- A3C#wJ
if nargin==5 && ischar(nflag) ZS@Cd9*
isnorm = strcmpi(nflag,'norm'); OE(Z)|LF
if ~isnorm MH+t`/E0]
error('zernfun:normalization','Unrecognized normalization flag.') ]R8}cbtU
end !'()QtvC<
else 5__8+R
isnorm = false; u:Q_XXT5
end =8?gx$r2
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% _
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% Compute the Zernike Polynomials G9.+N~GZ.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 0i2ZgOJ
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% Determine the required powers of r: `Tx1?]
% ----------------------------------- ceDe!Iu
m_abs = abs(m); w1-/U+0o
rpowers = []; 2-9'zN0u
for j = 1:length(n) V/Q~NXN
rpowers = [rpowers m_abs(j):2:n(j)]; 8m0GxgS
end +SGM3tY
rpowers = unique(rpowers); 72qbxPY13h
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% Pre-compute the values of r raised to the required powers, )6# i>c-
% and compile them in a matrix: Tz H*?bpP
% ----------------------------- !xm87I
if rpowers(1)==0 5Uc!;Gd?b
rpowern = arrayfun(@(p)r.^p,rpowers(2:end),'UniformOutput',false); 2YD;Gb[8
rpowern = cat(2,rpowern{:}); ?d)I!x,;;
rpowern = [ones(length_r,1) rpowern]; d7+YCi?
else /F;b<kIy8
rpowern = arrayfun(@(p)r.^p,rpowers,'UniformOutput',false); Y]ML-smN
rpowern = cat(2,rpowern{:}); LEoL6ga
end __\Tv>Y
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% Compute the values of the polynomials: 1=x4m=wV
% -------------------------------------- /xmUu0H$R
y = zeros(length_r,length(n)); I4kN4*d!N,
for j = 1:length(n) t&+f:)n
s = 0:(n(j)-m_abs(j))/2; u%FG%
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pows = n(j):-2:m_abs(j); n22k<@y
for k = length(s):-1:1 {umdW
x.*
p = (1-2*mod(s(k),2))* ... )J&