The Zernike polynomials are a set of orthogonal polynomials that arise in the expansion of a wavefront function for optical systems with circular pupils. The odd and even Zernike polynomials are given by
(1)
|
where the radial function is defined for
and
integers with
by
(2)
|
Here,
is the azimuthal angle with
and
is the radial distance with
(Prata and Rusch 1989). The even and odd polynomials
are sometimes also denoted
(3)
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(4)
|
Zernike polynomials are implemented in the Wolfram Language as ZernikeR[n, m, rho].
Other closed forms for include
(5)
|
for
odd and
,
where
is the gamma function and
is a hypergeometric
function. This can also be written in terms of the Jacobi
polynomial
as
(6)
|
The first few nonzero radial polynomials are
(7)
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(8)
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(9)
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(10)
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(11)
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(12)
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(13)
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(14)
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(15)
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(Born and Wolf 1989, p. 465).
The radial functions satisfy the orthogonality relation
(16)
|
where
is the Kronecker delta, and are related to the
Bessel function of the first kind
by
(17)
|
(Born and Wolf 1989, p. 466). The radial Zernike polynomials have the generating function
(18)
|
(correcting the typo of Born and Wolf) and are normalized so that
(19)
|
(Born and Wolf 1989, p. 465).
The Zernike polynomials also satisfy the recurrence relations
(20)
|
(Prata and Rusch 1989). The coefficients and
in the expansion of an arbitrary radial function
in terms of Zernike polynomials
(21)
|
are given by
(22)
|
where
(23)
|
Let a "primary" aberration be given by
(24)
|
with
and where
is the complex conjugate of
, and define
(25)
|
giving
(26)
|
Then the types of primary aberrations are given in the following table (Born and Wolf 1989, p. 470).
aberration | |||||
spherical aberration | 0 | 4 | 0 | ||
coma | 0 | 3 | 1 | ||
astigmatism | 0 | 2 | 2 | ||
field curvature | 1 | 2 | 0 | ||
distortion | 1 | 1 | 1 |