Datalogic matrix 450N, Руководство по продукции

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98 MATRIX 450N
READING DIAGRAMS
• The following reading diagrams are to be considered as references and are given
for typical performance at 25°C using high quality grade A symbols: Code 128 (1D
code) and Data Matrix ECC 200 (2D code) from the Test Charts provided with the
reader.
• Testing should be performed with the actual Matrix 450N + LT-03x assembly using
application codes in order to evaluate whether maximizing application perfor-
mance requires adjustments to the HW/SW configuration with respect to the Ref-
erence Conditions given under each diagram.
• The ratio of the Vertical FOV width with respect to the Horizontal FOV width in the
diagrams is about equal to 0.84; specifically 2050/2448. (i.e. FOV
V.

FOV
H
x 0.84).
• The focus and reading distance ranges are measured from the Lens Cover window
surface.
• When using a 25 mm focal length lens (LNS-1225), it is possible to use Super Nar-
row Angle Lighting Systems (LT-030 or LT-031) as well as the Narrow Angle Lighting
System LT-032. It is suggested to use the LT-032 in applications with very low con-
trast codes and in all cases where the higher lighting power of the LT-030 isn't nec-
essary. LT-030 and LT-031 Lighting Systems are especially effective in high speed
code movement applications.
• When defining a HW/SW configuration for the Matrix 450N + LT-03x assembly for
conditions different from those of the reference diagrams, it is suggested to keep
in mind the following rules:
- Changes in the diaphragm aperture influence the depth of field (reading distance
range) and the luminosity of the image. Increasing the diaphragm aperture by
one stop (i.e. form F/8 to F/5.6 or from F/11 to F/8) doubles the luminosity of the
image but can cause significant reduction in the reading distance range.
-Changes in Exposure Time act directly proportional to the luminosity of the image
and inversely proportional to the maximum code reading movement speed. Con-
sequently, reducing the
Exposure Time by half, reduces the luminosity of the
image by half but doubles the theoretical code reading movement speed.
-Changes in Gain act directly proportional to the luminosity of the image. Increas-
ing the Gain value however, can reduce the quality of the acquired image.
-The LT-030 lighting power (at the center of the field of view) is about equal to
twice that of the LT-031 and 3.5 times that of the LT-032.
For example, for the purpose of only changing the luminosity of the image, the follow-
ing three adjustments are equivalent:
increase the diaphragm aperture by one stop;
double the
Exposure Time ;
double the Gain .