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, ]w>o=<?b
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, ^wWbW&<Tg
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? W;=Ae~
那些系数是通过对29525*10阶的矩阵每列的值算出来的嘛? 2<B'PR-??y
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function z = zernfun(n,m,r,theta,nflag) (o IGp
%ZERNFUN Zernike functions of order N and frequency M on the unit circle. V6P-?Nd
% Z = ZERNFUN(N,M,R,THETA) returns the Zernike functions of order N cQhr{W,Un
% and angular frequency M, evaluated at positions (R,THETA) on the :p}8#rb
% unit circle. N is a vector of positive integers (including 0), and CR'%=N04^
% M is a vector with the same number of elements as N. Each element "g5{NjimY
% k of M must be a positive integer, with possible values M(k) = -N(k) f%.Ngf9
% to +N(k) in steps of 2. R is a vector of numbers between 0 and 1, xrvM}Il
% and THETA is a vector of angles. R and THETA must have the same g|]HS4y
% length. The output Z is a matrix with one column for every (N,M) I4jRz*Ufe?
% pair, and one row for every (R,THETA) pair. pml33^*<U
% e^\e;>Dh>
% Z = ZERNFUN(N,M,R,THETA,'norm') returns the normalized Zernike y&
yf&p
% functions. The normalization factor sqrt((2-delta(m,0))*(n+1)/pi), V($V8P/
% with delta(m,0) the Kronecker delta, is chosen so that the integral *'{-!Y
% of (r * [Znm(r,theta)]^2) over the unit circle (from r=0 to r=1, lh'S_p8g
% and theta=0 to theta=2*pi) is unity. For the non-normalized <$e|'}>A
% polynomials, max(Znm(r=1,theta))=1 for all [n,m]. 24#qg'
% @T\n@M]
% The Zernike functions are an orthogonal basis on the unit circle. #}y8hzS$
% They are used in disciplines such as astronomy, optics, and JXJ+lZmsz
% optometry to describe functions on a circular domain. :CE4<
{V
% a)ry}E =f
% The following table lists the first 15 Zernike functions. 70 7( LG
% '+_>PBOc
% n m Zernike function Normalization
gEj#>=s
% -------------------------------------------------- WuUwd#e
% 0 0 1 1 5_'lu
% 1 1 r * cos(theta) 2 J;obh.}u"{
% 1 -1 r * sin(theta) 2 To>,8E+GAb
% 2 -2 r^2 * cos(2*theta) sqrt(6) RX>P-vp
% 2 0 (2*r^2 - 1) sqrt(3) }?9&xVh?\
% 2 2 r^2 * sin(2*theta) sqrt(6) *z VN6wG{
% 3 -3 r^3 * cos(3*theta) sqrt(8) zw+aZDcV(
% 3 -1 (3*r^3 - 2*r) * cos(theta) sqrt(8) =p'+kS+
% 3 1 (3*r^3 - 2*r) * sin(theta) sqrt(8) QKj0~ia
5
% 3 3 r^3 * sin(3*theta) sqrt(8) RJ3oI+gI
% 4 -4 r^4 * cos(4*theta) sqrt(10) t>cGfA
% 4 -2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) Ldjz-
% 4 0 6*r^4 - 6*r^2 + 1 sqrt(5) /dYv@OU?
% 4 2 (4*r^4 - 3*r^2) * cos(2*theta) sqrt(10) VdK%m`;2
% 4 4 r^4 * sin(4*theta) sqrt(10) 3>1^$0iq
% -------------------------------------------------- pjFO0h_Y
% Y'|,vG
% Example 1: xW`y7Q }p
% z/{X{+Z
% % Display the Zernike function Z(n=5,m=1) e7U\gtZ.
% x = -1:0.01:1; v~Q'm1!O4\
% [X,Y] = meshgrid(x,x); uAPVR
% [theta,r] = cart2pol(X,Y); 7l69SQo]?
% idx = r<=1; vt#;j;liG
% z = nan(size(X)); B}d&tH2^s
% z(idx) = zernfun(5,1,r(idx),theta(idx)); w2nReB z
% figure ,_3hbT8Q
% pcolor(x,x,z), shading interp @zg}x0]
% axis square, colorbar tON>wmN
% title('Zernike function Z_5^1(r,\theta)') R (~wSL*R>
% ^OY]Y+S`Ox
% Example 2: 2cYBm^o|x
% >u$8Z
% % Display the first 10 Zernike functions s7Agr!>f
% x = -1:0.01:1; C.jWT1
% [X,Y] = meshgrid(x,x); sP(+Z^/
% [theta,r] = cart2pol(X,Y); #Lhv=0op
% idx = r<=1; rR.It,,
% z = nan(size(X)); Xi&J%N'
% n = [0 1 1 2 2 2 3 3 3 3]; bT.q@oU
% m = [0 -1 1 -2 0 2 -3 -1 1 3]; y'_8b=*
% Nplot = [4 10 12 16 18 20 22 24 26 28]; -@#w)
% y = zernfun(n,m,r(idx),theta(idx)); .hat!Tt9
% figure('Units','normalized') Y b+A{`
% for k = 1:10 T0w_d_aS
% z(idx) = y(:,k); D`LBv,n
% subplot(4,7,Nplot(k)) P"vrYom
% pcolor(x,x,z), shading interp n[ B~C
% set(gca,'XTick',[],'YTick',[]) sT\:**
% axis square yn62NyK
% title(['Z_{' num2str(n(k)) '}^{' num2str(m(k)) '}']) T`EV
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% end (9'^T.J
% 7N9NeSH
% See also ZERNPOL, ZERNFUN2. }g}Eh>U
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% Paul Fricker 11/13/2006 bU!
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% Check and prepare the inputs: _VrY7Mz:r
% ----------------------------- \/NF??k,jk
if ( ~any(size(n)==1) ) || ( ~any(size(m)==1) ) T D_@0Rd
error('zernfun:NMvectors','N and M must be vectors.') Q7s@,c!m_
end js_`L#t
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if length(n)~=length(m) Kw
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error('zernfun:NMlength','N and M must be the same length.') 5> x_G#W
end k +-w%
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n = n(:); #4^d#Gj
m = m(:); >@YefNX6
if any(mod(n-m,2)) _;1{feR_
error('zernfun:NMmultiplesof2', ... ,;)ZF
'All N and M must differ by multiples of 2 (including 0).') 7>E.0DP
end "z~ba>,-\
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if any(m>n) V0nQmsP1U
error('zernfun:MlessthanN', ... \|;\
'Each M must be less than or equal to its corresponding N.') +hxG!o?O
end Wq1>Bj$J8
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if any( r>1 | r<0 ) %M(RV_R+6
error('zernfun:Rlessthan1','All R must be between 0 and 1.') ^#/FkEt7bp
end *%j$i_
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if ( ~any(size(r)==1) ) || ( ~any(size(theta)==1) ) 7;'33Bm*
error('zernfun:RTHvector','R and THETA must be vectors.') >L7s[vKn
end 'YL[s
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r = r(:); yYG<tUG;
theta = theta(:); &gXh:.
length_r = length(r); c`a(
if length_r~=length(theta) R@vcS=m7
error('zernfun:RTHlength', ... %Sr+D{B
'The number of R- and THETA-values must be equal.') ]R__$fl`8
end Tg\bpLk0=
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% Check normalization: Cm}2 >eH
% -------------------- {MUB4-@?F$
if nargin==5 && ischar(nflag) %oZ:Awx
isnorm = strcmpi(nflag,'norm'); 0'QWa{dS\
if ~isnorm Uzu6>yT
error('zernfun:normalization','Unrecognized normalization flag.') <wH+\
end T<AT&4
else ]-fkmnmWX
isnorm = false; 4=zs&
end zkQ[<
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% "}4%v Zz
% Compute the Zernike Polynomials !rvEo =^
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% )Fw/Cu
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/ HTY>b
% Determine the required powers of r: 2-&EkF4p'
% ----------------------------------- `8:0x?X
m_abs = abs(m); $pGT1oF[E
rpowers = []; MK$u}G
for j = 1:length(n) .L'w/"O
rpowers = [rpowers m_abs(j):2:n(j)]; 8[^'PIz
end i!wU8@
rpowers = unique(rpowers); }aCa2%
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7nZPh3%
% Pre-compute the values of r raised to the required powers, q'2vE;z Kb
% and compile them in a matrix: yU? jmJ
% ----------------------------- !3ggQG!e
if rpowers(1)==0 NkE0S`Xf
rpowern = arrayfun(@(p)r.^p,rpowers(2:end),'UniformOutput',false); ,Kit@`P%
rpowern = cat(2,rpowern{:}); \bA Yic
rpowern = [ones(length_r,1) rpowern]; `?Rq44=
else (~T*yH ~
rpowern = arrayfun(@(p)r.^p,rpowers,'UniformOutput',false); t^t% >9o
rpowern = cat(2,rpowern{:}); XR5KJl
end 2_o#Gx'
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% Compute the values of the polynomials: @NHh-&;w
% -------------------------------------- {7o#Ve
y = zeros(length_r,length(n)); 4ls:BO;k]
for j = 1:length(n) Ic&h8vSU
s = 0:(n(j)-m_abs(j))/2; i;[y!U
pows = n(j):-2:m_abs(j); p 7?
for k = length(s):-1:1 G)3I+uxn
p = (1-2*mod(s(k),2))* ... +2tQFV;
prod(2:(n(j)-s(k)))/ ... 5{Cz!ut;tE
prod(2:s(k))/ ... md!6@)S-p
prod(2:((n(j)-m_abs(j))/2-s(k)))/ ... +SJ.BmT
prod(2:((n(j)+m_abs(j))/2-s(k))); dWqn7+:
idx = (pows(k)==rpowers); |s| }u`(@9
y(:,j) = y(:,j) + p*rpowern(:,idx); X1L@
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end ~z,o):q1}
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if isnorm L9x-90'q,
y(:,j) = y(:,j)*sqrt((1+(m(j)~=0))*(n(j)+1)/pi); 5J5si<v25
end K*6 "c.D
end 4<s.|W`
% END: Compute the Zernike Polynomials 9KSi-2?H
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% xad`-vw
@=J|%NO
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% Compute the Zernike functions: @Mk`Tl
% ------------------------------ ]B8
A
idx_pos = m>0; q76POytV|
idx_neg = m<0; MvVpp;bd
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%}|v/
h}b:-a
z = y; VYyija:
if any(idx_pos) Z`Yt~{,Q
z(:,idx_pos) = y(:,idx_pos).*sin(theta*m(idx_pos)'); x2"iZzQlD
end 50UdY9E_v}
if any(idx_neg) GW2\YU^{
z(:,idx_neg) = y(:,idx_neg).*cos(theta*m(idx_neg)'); 18g_v"6o
end _03?XUKV
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% EOF zernfun 8^mE<