SICK ICR 84x, Руководство по эксплуатации

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Chapter 3 Operating instructions
ICR 84x Image Code Reader
3-6
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SICK AG · Division Auto Ident · Germany · All rights reserved 8 010 961/0000/10-05-2005
Product description
3.2 Method of operation
The ICR uses an image recording and processing system (CMOS matrix sensor with 1280
x 1024 pixels) to scan 2-D codes and bar codes with a rectangular reading area. To do so,
LEDs integrated in the housing illuminate the area to be read. The LEDs generate a red
illumination field (pulsed) with a configurable flash duration. To start a reading cycle, the ICR
switches on the illumination. It absorbs the light reflected from the reading area ( Fig. 3-2 )
through the lens as gray values of an image area, which are stored in an electronic image
memory (image refresh rate: 25 Hz at full memory utilization).
To prevent distorted images in the image buffer memory, the object with the code must
remain stationary while the image is being recorded.
The reading area (surface), which is mapped in sharp focus by the ICR in its image memory,
depends on the reading distance and, depending on the resolution, must be within the
reading area (DOF). Fig. 9-4, Page 9-5 shows the available reading area.
If the appropriate configuration settings are made to reduce the image buffer memory area
(image geometry) used for the evaluation, this increases the potential image refresh rate.
The refresh rate with the VGA resolution (640 x 480 pixels) is 60 Hz, for example. The ICR
automatically adjusts the flash frequency. With a maximum of two working areas, a
maximum of just two separate strips in the image field can be evaluated.
As 2-D-codes or bar codes are detected in the image data, the ICR's decoding algorithms
determine the code(s) contents. At the end of the reading cycle or immediately after
successful decoding, the ICR outputs the code data information via its data interface (main
data interface: Host, CAN or Ethernet interface) to a host/PC for further processing.
Fig. 3-2: Reading area of the ICR in the focus position (standard type)
All dimensions in mm (in)
Fig. 3-3: Block diagram: functions of the ICR
Photoelectric switch
Reading pulse
Signal
Path increment
Teach-in match code 1
End of reading interval
PC
Operation
Parameterizing etc.
Status indicator
e.g. Good Read
e.g. No Read
HOST
CAN bus
Image output