Microscan Visionscape FrontRunner, User Manual

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Illuminating the Part
Creating a Good
Image
A
v4.1.3, April 2012 Visionscape FrontRunner™ User’s Manual A-7
Note: Fluorescent lighting tends to be diffuse and not concentrated on a
part. If the part is being magnified by a lens or if the lens aperture is small
(stopped down), you may find the light level insufficient.
a.
It is usually necessary to place an infrared filter in front of the
camera lens when using an incandescent light source. The
camera has a high sensitivity to infrared light that reduces the
contrast and resolution found in an image.
b.
If you use fiber-optics, the part being illuminated is not heated. If
you use conventional bulbs, the part being inspected may get hot.
Lasers
A laser is an excellent source of light when you need to:
• Illuminate a small area
• Create a structured lighting effect
• Create a three-dimensional simulation, for example, measure depth
Strobe Lights
Use a strobe light when you need to freeze the image of a moving part.
Strobes provide a very short-duration, high-intensity light. In most cases
you should use fiber-optics to project the light to the required area.
TABLE A–2.
Incandescent Lighting
Positive Features Negative Features
High intensity Shorter life than fluorescent
Inexpensive if you use home light
bulbs Expensive if fiber-optic lights are used
No flicker Source of infrared light
a
Light output constant over life of
bulb Creates excessive heat
b