Symbol LS 1220, Product Reference Manual

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LS 1220 Product Reference Guide
Housing Design
The scan engine housing design must be such that internal reflections from the outgoing
laser beam are not directed back toward the detector. The reflections from the front corners
of the scan engine housing near the exit window and from the window itself can often be
troublesome. Also, for particular window tilt angles, reflections from the window can bounce
off the top or bottom of the housing and reach the detector.
ESD
The LS 1220 is protected from ESD events that may occur in an ESD-controlled
environment. Always exercise care when handling the module. Use grounding wrist straps
and handle in a properly grounded work area.
Location and Positioning
Caution
The general Location and Positioning guidelines provided, do not consider
unique application characteristics. It is recommended that an opto-
mechanical engineer perform an opto-mechanical analysis prior to
integration.
Using the LS 1220 as an Embedded Scanner
Some applications require the LS 1220 be mounted to read symbols that are automatically
presented, or that are presented in a pre-determined location. In these applications
LS 1220 positioning (with respect to the symbol) is critical. Failure to properly position the
LS 1220 with respect to the symbol may lead to degraded or unsatisfactory reading
performance.
Two methods of positioning the scanner have been provided:
The Calculating The Usable Scan Length Method on page 2-5, can be used with
consistently good quality symbols. It provides a mathematical solution to find the
usable scan length.
The Testing The Usable Scan Length Method on page 2-6, uses real situation testing
to adjust the usable scan length to fit the application conditions.