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High-Speed Image Processing Circuit
The stripe light is scanned on the CCD image plane at two horizontal lines per frame (FAST mode) or one hor-
izontal line per frame (FINE mode), and the CCD is driven so that the block readout start position is shifted
two lines per frame (FAST mode) or one line per frame (FINE mode).
Approximately 270 frames of the imager are acquired in FAST mode, whilst approximately 600 frames are ac-
quired in FINE mode.
· CCD drive rate: 12.5MHz
· Block readout: 36 lines (FAST mode)/125 lines (FINE mode)
· Data acquisition speed: 0.3 sec. (FAST mode)/2.5 sec. (FINE mode)
The output signal from the CCD is then converted into a digital signal, which is then subjected to digital signal
processing. The signal processed data is finally saved in the frame memory.
Time center of gravity and Space center of gravity
Time center of gravity is the center of gravity of the variation in the LD light passing CCD's one picture ele-
ment over a period of time.
Space center of gravity is the center of gravity of the spatial variation in the LD light on the CCD at a certain
time.
With this instrument, 3D images are obtained by calculating the Time center of gravity of each picture element
of CCD. Intersection of the viewing angle of each picture element of the CCD and passing angle (time) of the
stripe light is calculated.
Compared to the Space center of gravity, use of Time center of gravity can reduce influences of sensitivity vari-
ation of CCD's picture elements and variation of brightness of the object.
Frame interline
Transfer CCD
A/D
FIFO
Clock Generator
Galvano
Laser
Scanner
Diode
Driver
Explanation of Measuring Principle
Frame
Memory
DSP
Host I/F
CPU
CPU Data Bus
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