Olympus CX23 - Optical Characteristics

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CX23
8 Optical characteristics
The following table shows the optical performances of
combinations of eyepieces and objectives.
The figure on the right shows the performances
indicated on the objectives.
Magnification
Mechanical tube
length
Objective type (on the back side)
Plan objective
Color band
Numerical aperture
Field number
Cover glass thickness
Optical
performance
Objectives
Magnifi-
cation
Nu-
merical
aperture
N.A.
Working
distance
W.D.
(mm)
Cover
glass
thickness
(mm)
Resolution
(µm)
10X Eyepieces (FN 20)
Remark
Total
magnifi-
cation
Depth of
focus
(µm)
Actual
field of
view
Plan objective
(FN 20)
CX22PL100XO (option)
4X
10X
40X
100XO
0.10
0.25
0.65
1.25
27.8
8.0
0.6
0.13
-
-
0.17
-
3.36
1.34
0.52
0.27
40X
100X
400X
1000X
175.0
28.0
3.04
0.69
5.0
2.0
0.5
0.2
Oil immersed
Glossary Meaning
Working distance (WD) Distance between the top surface of the cover glass and the top of the objective when in
focus.
Number of aperture (NA) This value corresponds to the F-number* of the camera and is related to the resolution.
Resolution becomes higher when the NA becomes larger.
(*F-number : Value dividing the focal length of the lens by the effective number of aperture.
This is used as an index to represent the brightness of the lens.)
Resolution Ability of an objective for resolving adjacent two points in the image, which is expressed in
terms of the minimum distance between two points on the specimen surface.
Focal depth
(Object side)
The depth range of a specimen, in which focus is obtained. Stopping down the aperture
iris diaphragm increases the depth of focus. The depth of focus is decreased when the NA
of objective becomes larger.
Field number (FN) The diameter of the image observed through an eyepiece, indicated in millimeters.
Actual field of view Diameter of the field of view, expressed as the size on the specimen surface.
Total power
(Total magnification)
Objective magnification x Eyepiece magnification.