Newland NLS-EM3296, Руководство по интеграции

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4
Optics
Window Placement
The window should be positioned properly to let the illumination and aiming beams pass through as much
as possible and no reflections back into the engine (reflections can degrade the reading performance).
The window should be mounted close to the front of the engine (parallel). The maximum distance is
measured from the front of the engine housing to the farthest surface of the window. In order to reach
better reading performance, the distance from the front of the engine housing to the nearest surface of the
window should not exceed
a
(
a
=0.5mm) and the thickness of window should not exceed 2mm.
If the window is required to be in a tilted position, the distance requirements above should be met and tilt
angle should ensure no reflections back into the lens.
Window Material and Color
CIS
’s responsiveness (mainly to wavelengths of red light
）
should be taken into consideration when
choosing window material and color, in order to achieve the possible highest spectral transmission, lowest
haze level and homogeneous refractive index. It is suggested to use PMMA or optical glass with spectral
transmittance over 90% and haze less than 1%. Whether to use an anti-reflection coating or not depends
on the material and application needs.