Joe is still working on the proper lense system for resolving a 25um wire using microscope objectives
and a CCD camera.
I found an useful application note for designing optics in the Edmund Optics catalog 2001 and derived a
compound microscope system. Edmund sells an Optical Layout Including Video Elements Software called OLIVE
(http://www.highchiva.com/OLIVE.htm).
Today the OLIVE cdrom has arrived and I designed a compound microscope made of 2 stock lenses.
The programm is very intuitive and gives a feeling how sensitive the system is for lense adjustment.
Attached is a draft version based on Edmund stock lenses.
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The object size is set to 25um (wire diameter) and I'm aiming for an image of ~1.5mm on a 3.6x4.8mm CCD chip (1/3inch
size), equivalent to a PMAG = ~50 (lense magnification).
At present we use an analog monitor with a diameter of 13", which gives an electronic magnification of ~54
(diameter monitor/ diameter CCD). The total magnification of the wire scanner is 54*50=~2700
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1.Pic : wire scanner optics using a 20mm lense (12mm diameter) as an objectice and a 30mm lense (18mm diameter)
as an eyepiece. With this kind of short focus the CCD position matters.
2.Pic: wire scanner optics using a 20mm lense (Hastings type, 12.5mm diameter) and the same 30mm lense as an eyepiece.
Advantage is a parallel ray with quasi infinity focus hitting the CCD, so the location of the CCD does not really matter
. I inserted an iris (8mm diameter) for increasing the depth of view (DOV) by decreasing/limiting the angular
magnification ( and decreasing the Numerical Aperture as well)
.
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[SYSTEM DEFINITION]
DEFINITION="OBJECT SIZE"
SIZE=0.025
WAVELENGTH=587.600
[element 1]
TYPECODE=2
NAME=IRIS
POSITION=21.400
DIAMETER=7.000
[element 2]
COMPANY=Edmund
TYPECODE=0
NAME=HASTINGS
POSITION=23.497
PART #=45251
RADIUS=14.950000,7.340000,-7.340000,-14.950000\0D\0A
CENTER THICKNESS=1.100000,7.980000,1.100000\0D\0A
GLASS TYPE=F2,BK7,F2\0D\0A
GLASS PATHS="C:\\Program Files\\Olive2\\glass cats\\glasses.txt,,\0D\0A"
GLASS INDEX=1.615030,1.620040,1.632080,1.620040\0D\0A,1.514320,1.516800,1.522380,1.516800\0D\0A,1.615030,1.620040,1.632080,1.620040\0D\0A,
DIAMETER=12.500
BFL=0.000
EFL=20.000
ORIENTATION="NOT FLIPPED"
[element 3]
COMPANY=Edmund
TYPECODE=0
NAME=ACHROMAT
POSITION=133.998
PART #=45348
RADIUS=20.730000,-14.310000,-133.580000\0D\0A
CENTER THICKNESS=6.910000,2.000000\0D\0A
GLASS TYPE=BaFN10,SF10\0D\0A
GLASS PATHS="C:\\Program Files\\Olive2\\glass cats\\glasses.txt,\0D\0A"
GLASS INDEX=1.665790,1.670030,1.680010,1.670030\0D\0A,1.720850,1.728250,1.746480,1.728250\0D\0A,
DIAMETER=18.000
BFL=0.000
EFL=30.000
ORIENTATION="NOT FLIPPED"
Optical System Values
Paraxial Data
Surface Item Z Y marg. Y chief U marg. U chief Radius
Object 0.000 0.000 0.025 0.164 -0.001 inf.
1 A Iris 21.400 3.500 0.000 0.164 -0.001 inf.
2 Iris 21.400 3.500 0.000 0.164 -0.001 inf.
3 45251 23.497 3.843 -0.002 0.003 -0.001 14.950
4 45251 24.597 3.846 -0.003 0.038 -0.001 7.340
5 45251 32.577 4.152 -0.009 0.072 -0.001 -7.340
6 45251 33.677 4.232 -0.010 -0.059 -0.001 -14.950
7 F 45348 133.998 -1.671 -0.093 -0.003 0.001 20.730
8 45348 140.908 -1.691 -0.084 -0.007 0.001 -14.310
9 45348 142.908 -1.704 -0.082 -0.002 0.002 -133.580
Image -561.953 0.000 -1.691 -0.002 0.002 inf.
Exact Data
Surface Item Z Ye L/M Sag. Radius
Object 0.000 0.000 0.164 0.000 inf.
1 A Iris 21.400 3.500 0.164 0.000 inf.
2 Iris 21.400 3.500 0.164 0.000 inf.
3 45251 24.022 3.929 -0.007 0.525 14.950
4 45251 25.729 3.917 0.036 1.133 7.340
5 45251 31.312 4.119 0.076 -1.264 -7.340
6 45251 33.060 4.251 -0.061 -0.617 -14.950
7 F 45348 134.085 -1.906 0.001 0.088 20.730
8 45348 140.781 -1.901 -0.004 -0.127 -14.310
9 45348 142.894 -1.909 0.004 -0.014 -133.580
Image 643.609 0.000 0.004 0.000 inf.
System Data
Magnification -67.639
Image size -1.691
back focus -704.861
system length -704.861
Working F# 206.782
Ent. Pupil Position 21.400
Ent. Pupil Diameter 7.000
Optical Invariant 0.004
Exit Pupil Position 178.787
Exit Pupil Diameter 3.582
FOV 0.067
Object size 0.025
Stop radius 3.500
N.A. 0.163
Ang. Mag. -1.954
Seidel Coefficients
Spherical 4.569E-2 9.720
Coma 7.570E-5 0.064
Astig. 2.975E-6 0.003
Petzval 1.017E-6 0.000
Distortion -9.773E-8 0.000
TSA 9.448E+0 16079.008
LSA -3.907E+3 -6649690.478
MF 2.173E-2
Color
Longitudinal Axial -236.452
Lateral Color -0.531
Transverse Color 0.421
Axial (nf) -0.608
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