Appendix H Object Detector; Figure A-1 Object Detector - Microscan MS-3 User Manual

Appendix H — Object Detector
In a typical operation, a reader will wait for symbol data only during a triggered read
cycle. A read cycle is initiated by a "trigger" and can be in the form of a serial command
from the host (internal trigger) or a signal from an object detector (external trigger).
When an object detector (also called a sensor, package detector, etc.) is used, it is set
up so that its beam will bounce off the approaching object and the resulting pulse will
be sent to the reader to begin the read cycle. Typically, a detector is positioned so that
it will detect the presence of an object before its symbol can be read.
An object detector is mounted in almost any position relative to the object as long as
(1) the object passes within range of the detector and (2) direct or reflected light from
the detector does not interfere with the reader's reception.
As the item continues to move down the line, its symbol moves into the reader beam
and is read by the reader.
Bar coded item
Object
detector

Figure A-1 Object Detector

Bar coded item
MS-3
MS-3 CCD Reader User's Manual
Appendices
A-17