3
Figure 2-1
Optics
Window Placement
The window functions as an isolation wall in front of EM2037 to separate the engine from other parts of
the entire device. Meanwhile the window placement should ensure that the illumination and aiming
beams can come out and no reflection into the engine, otherwise the reading performance might be
affected.
The window should be mounted close to the front of the engine (parallel, no tilt). The maximum distance
is measured from the front of the engine housing to the farthest surface of the window. Avoid reflection of
illumination beams back to the engine and adopt thin material for window so as to reach better reading
performance. As shown below, the maximum distance should be no more than 3mm and the distance
from the front of the engine housing to the nearest surface of the window should be no more than 2mm.
Figure 2-2
If the window is required to be placed tilt, the distance should meet the same requirements as placed
parallel and the tilt angle should ensure no reflection back into the lens.
Window Material and Color
The wave-length of illumination and aiming beams should be taken into consideration when choosing
window material and color, so as to realize the possible highest transmission rate. The window should be
