Precise Eye High Mag Fixed Lenses
60
http://machinevision.navitar.com
• email: [email protected]
Precise Eye Performance Specifications
N.A. Object Side
Measurement at the object point of
the largest cone of light rays that are
entering the optical system.
Resolvable Features (microns)
Measurement of lens system’s ability
to image closely spaced points, lines
and object surfaces as separate enti-
ties.
Working Distance (W.D.)
Clearance between object and lowest
mechanical part of the system.
Depth of Field
The distance allowing acceptable image
definition to be maintained without
refocusing.
Magnification
A measure of the apparent difference in
size between the object and image.
Matching Pixel Size
Matching pixel size is that which will
permit the minimum feature size to
overlap two pixels.
N.A. Image Side
Measurement at the image point of the
largest cone of light rays that are enter-
ing the optical system.
Key Terms for Understanding the Matrix Charts
Precise Eye Combinations
Lens Atta Precise Eye + Rear Adapter
W.D.
Magnifi cation
N.A.
Object Side
Resolve Limits
(microns)
Depth
of Field
(mm)
Required
Matching Pixel
Size (microns)
0.25x + Precise Eye + 0.5x
356
0.23x
0.018
9.4
1.59
2.1
0.25x + Precise Eye + 0.67x
356
0.30x
0.018
9.4
1.59
2.8
0.25x + Precise Eye + 1.0x
356
0.45x
0.018
9.4
1.59
4.2
0.25x + Precise Eye + 1.33x
356
0.60x
0.018
9.4
1.59
5.6
0.25x + Precise Eye + 2.0x
356
0.90x
0.018
9.4
1.59
8.4
0.5x + Precise Eye + 0.5x
175
0.45x
0.035
4.7
0.40
2.1
0.5x + Precise Eye + 0.67x
175
0.60x
0.035
4.7
0.40
2.8
0.5x + Precise Eye + 1.0x
175
0.90x
0.035
4.7
0.40
4.2
0.5x + Precise Eye + 1.33x
175
1.20x
0.035
4.7
0.40
5.6
0.5x + Precise Eye + 2.0x
175
1.80x
0.035
4.7
0.40
8.4
0.75x + Precise Eye + 0.5x
113
0.68x
0.054
3.1
0.18
2.1
0.75x + Precise Eye + 0.67x
113
0.90x
0.054
3.1
0.18
2.8
0.75x + Precise Eye + 1.0x
113
1.35x
0.054
3.1
0.18
4.2
0.75x + Precise Eye + 1.33x
113
1.80x
0.054
3.1
0.18
5.6
0.75x + Precise Eye + 2.0x
113
2.70x
0.054
3.1
0.18
8.4
1.0x + Precise Eye + 0.5x
92
0.90x
0.071
2.3
0.10
2.1
1.0x + Precise Eye + 0.67x
92
1.21x
0.071
2.3
0.10
2.8
1.0x + Precise Eye + 1.0x
92
1.80x
0.071
2.3
0.10
4.2
1.0x + Precise Eye + 1.33x
92
2.39x
0.071
2.3
0.10
5.6
1.0x + Precise Eye + 2.0x
92
3.60x
0.071
2.3
0.10
8.4
1.5x + Precise Eye + 0.5x
51
1.35x
0.104
1.6
0.04
2.1
1.5x + Precise Eye + 0.67x
51
1.81x
0.104
1.6
0.04
3.0
1.5x + Precise Eye + 1.0x
51
2.70x
0.104
1.6
0.04
4.4
1.5x + Precise Eye + 1.33x
51
3.59x
0.104
1.6
0.04
5.8
1.5x + Precise Eye + 2.0x
51
5.40x
0.104
1.6
0.04
8.6
2.0x + Precise Eye + 0.5X
36
1.80x
0.141
1.2
0.02
2.1
2.0x + Precise Eye + 0.67x
36
2.41x
0.141
1.2
0.02
2.8
2.0x + Precise Eye + 1.0x
36
3.60x
0.141
1.2
0.02
4.2
2.0x + Precise Eye + 1.33x
36
4.79x
0.141
1.2
0.02
5.6
2.0x + Precise Eye + 2.0x
36
7.20x
0.141
1.2
0.02
8.4
Assumptions:
1. Minimum resolvable feature size is half of the threshold line pair limit. Calculation = 1/(3000 x Lens N.A.)
2. Matching pixel size is that which will permit the minimum feature size to overlap two pixels. Calculation = 1/2(Feature Size x System Magnifi cation)
3. If the matching pixel size is greater than the camera pixel size, the system is “lens limited.”
4. If the matching pixel size is less than the camera pixel size, the system is “camera limited.”
