Easson EX-100, Руководство пользователя

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Fig. 1 Raster measuring system
2.2 raster digital display system
It includes a raster measuring system and a digital display system
2.2.1 the raster measuring system consists of a scale and a reading head(Its theory is
shown as Fig.1).
a) Lighting system
The raster reading head adopts an infrared light emitting diode as a light source. The
light becomes parallel light on the scale surface with
scales by a condenser. The
infrared light emitting diode owns a high luminous efficiency with extremely low
temperature and can work at low voltage and small current. It is compact, with long
life and high reliability.
b) Photoelectric translation
The scale is a black-and white raster with 100 scales at each 1mm. The indicating
raster is a tetrad division phases. When adjusting the former scales to parallel with
the latter ones, the light gate (Mohr fringe) will occur during the both raster moving
relatively due to light transmission effect and light screening effect. The silicon
photocell at back of the indicating raster receives periodic change light flux which
transfers into electric signals with 0 , 90, 180 and 270 phase differences. Then
these signals are sent into the digital display system.
2.2.2 The digital display system is supported by an EDS100 fine digital display
hardware and corresponding software ED101 .
3. Specification
3.1 Measuring range mm