????????(Aberration)

1
????????(Aberration)

• Spherical aberration (on axis)
• Coma
• Astigmatism (off axis)
• Curvature of field
• Distortion
• Chromatic aberration

2
Spherical aberration
3
Circle of least confusion
Caustic
Longitudinal S.A.
Traverse S.A.
4
Negative SA
Positive SA
5
????? S.A
1. ?????????????????????????????????? 2.
??????????? ??? infinite conjugate lens 3.
??? Stop 4. ??? Aspherical lens ???
6
Shape factor
7
(No Transcript)
8
Comatic aberration
No SA
Positive CA
Negative CA
9
Stop
field stop
Aperture stop
??????????????
??????????????????????
10
pupil
Exit pupil ??????AS ?????? OBJ
Entrance pupil ??????AS ?????? IMG
11
Comatic aberration (CA)
12
Tangential section
sagittal section
13
????? C.A
1. ?????????????????????????????????? 2.
??????????? 2. ??? Stop
14
(No Transcript)
15
tangential plane
Sagittal plane
No CA , No Asigmatism
16
Astigmatism
Fs
FT
Slc
S
17
Fs
FT
Zlc
S
18
S
T
T
S
F
F
Chief ray
Chief ray
Negative astigmatism
Positive astigmatism
19
????? Astigmatism
1. ??????????????? 2. ??????????? 3.
??? Stop
p--gtPetzval surface
20
Curvature of field
p
21
Flattening the field (???????????)
n1f1n2f20
22
Distortion
orthoscopic
barrel
Pin cushion
23
?????? Distortion ???? stop
24
Chromatic aberration (ChA)
25
Achromatic doublet
f1V1f2V20
1
2
Abbe number
(1/dispersive power)
26
Minimum ChA
27
Dispersive power

28
Fraunhofer lines
Dark absorption features in the solar spectrum.
J. von Fraunhofer first studied them in 1814.
They occur from the ultraviolet at about 180
nanometers to the infrared at 20 micrometers.
29
Designa tion Ele ment Wave length (nm) Desig nation Ele ment Wave length (nm)
y O2 898.765 c Fe 495.761
Z O2 822.696 F Hß 486.134
A O2 759.370 d Fe 466.814
B O2 686.719 e Fe 438.355
C Ha 656.281 G' H? 434.047
a O2 627.661 G Fe 430.790
D1 Na 589.592 G Ca 430.774
D2 Na 588.995 h Hd 410.175
D3 or d He 587.5618 H Ca 396.847
e Hg 546.073 K Ca 393.368
E2 Fe 527.039 L Fe 382.044
b1 Mg 518.362 N Fe 358.121
b2 Mg 517.270 P Ti 336.112
b3 Fe 516.891 T Fe 302.108
b4 Fe 516.891 t Ni 299.444
b4 Mg 516.733
Using Fraunhofer lines
f1dV1df2dV2d0
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(No Transcript)
31
Separated achromatic doublet
2
1
d
ny(nBnR)/2
Using Fraunhofer lines
32
Minimum ChA
n1R n2R ,
n1B n2B
33
Aplanatic system
n2
n1
oil
so
34
A
R
C
O
I
q1
q2
R
R
q1
q2