Symbol SE 923, Integration Manual

Page: 28 / 238

2-6
SE-923 Scan Engine Integration Guide
Environment
The SE-923-I000A must be sufficiently enclosed to prevent dust particles from gathering on
the mirrors, laser lens, and the photodiode. Dust and other external contaminants will
eventually cause degradation in unit performance. Symbol does not warrant performance of
the engine when used in an exposed application.
Optical
The SE-923-I000A uses a sophisticated optical system that is capable of providing scanning
performance that can match or exceed the performance of much larger scanners. However,
the performance of the scan engine can be affected by an improperly designed enclosure, or
improper selection of the window material.
Positioning the Window
The window must be positioned so that laser light reflected off the inside of the window
is not reflected back into the collection optics of the scan engine. The window can be
positioned more nearly parallel to the face of the scanner if an anti-reflection coating is used.
Once again, we stress that the specified angles are minimums and care must be exercised
to allow for manufacturing tolerances. Larger angles are generally preferred. If the
enclosure you’ve designed cannot accommodate the recommended window angle, contact
Symbol Technologies to discuss your requirements. An improperly positioned window can
result in significant performance degradation. Figure 2-3 illustrated the positions of the exit
window in reference to the scan engine. Table 2-1 lists the required exit window dimensions
and Table 2-2 lists the required exit window tilt angles. The exit window can be tilted away
from (case 1) the scan engine or toward (case 2) the scan engine. The exit window size and
tilt varies according to the distance from the scan engine.