Matrix Vision mvBlueGEMINI, Technical Manual

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mvBlueGEMINI Technical Manual (EN) v 1.2.2
APPENDIX - CHOICE OF THE RIGHT LENS AND LIGHTING SYSTEM
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B = Diffraction disk or point image
F = Focal length
D = Aperture diameter
Example with gree
n light and λ = 0.5 µm
F-number F/D Diameter diffraction disk
1 1.25 µm
4 5 µm
16 20 µm
10.4.2 Find the correct lighting system
Besides optics, the illumination is an important point, which is critical for good results in the image
processing. The golden rule is: create contrast.
A lighting system can be homogeneous or structured. Following table shows the effects and the
characteristics of lighting systems:
Effects Light specifications
Without
structure

light on object

light as a contrast to the object

no information by the light

information from the object

must be homogeneous

must be time stable

must be broadband in
color
With structure

underlines specific characteristics

color changes contrast of details

projected lines perform a coordin ate
transformation

usually disturbing reflections become
information

is definied structured

is limited to light bands