Fairchild CAM/CCD-4KCL.TDI - Manual (Page 25)

4.4 Lenses
Fairchild Imaging does not supply lenses; contact your local optics supplier for
available lens models.
4.5 Illumination
The amount and wavelengths of light required to capture useful images depend on
the particular application. Factors include the nature, speed, and spectral
characteristics of objects being imaged, exposure times, light source characteristics,
environmental and acquisition system specifics.
It is often more important to consider exposure than illumination. The total amount
of energy (which is related to the total number of photons reaching the sensor) is
more important than the rate at which it arrives. For example 5
µJ/cm 2 can be
achieved by exposing 5 mW/cm 2 for 1 mS just the same as exposing an intensity of
W/cm 2 for 1 µs.
4.6 Light Sources
Keep these guidelines in mind when setting up your light source.
• Halogen light sources generally provide very little blue relative to IR.
• Fiber-optic light distribution systems generally transmit very little blue relative to IR.
Some light sources age; over their lifespan they produce less light. This aging may
not be uniform – a light source may produce progressively less light in some areas
of the spectrum but not others.
Fairchild Imaging • CAM/CCD 2KCL.TDI & CAM/CCD-4KCL.TDI Line Scan Camera User’s Manual • Rev C• 25 of 30