Hamamatsu Photonics C8484-16C, Инструкция по эксплуатации

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C8484-16C Instruction manual Ver.1.5
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9. IMAGE ACQUISITION
9-1 DESCRIPTION OF HOW THE CCD FUNCTIONS
The all-pixel-readout interline transfer CCD used in this camera is arranged as shown in
Figure 9-1. Incident light at the CCD is converted by photosensors to electrical charges
which are transmitted through a shielded vertical transfer CCD (VCCD) and a horizontal
transfer CCD (HCCD) to a final output charge-voltage conversion amp. The sensor gate is
opened by the readout signal, and the charges generated by all of the photosensors are
transmitted unmixed to the VCCD, completing the exposure.
In addition, an electronic shutter signal is applied to the CCD, allowing any accumulated
charge in the photosensors to be discharged.
Photo-diode
Vertical CCD Sensor gate
ON-chip AMP Horizontal CCD
Figure 9-1
 Binning: Accumulated charges for a specified number of pixels in the vertical and
horizontal directions on the CCD are calculated and combined (binned), then
read out from the CCD. With this camera, binning can be set to 2

2, where two
pixels in the vertical and horizontal directions are combined, 4

4, where four
vertical and horizontal pixels are combined.

Exposure time:
When set to the normal CCD scanning mode, this is as shown in Figure 9-2.
Exposure time is the elapsed time between one readout signal and the next;
this interval is at least as long as the time necessary for all of the charges from
the CCD to be read out.
Readout period
CCD exposure
Readout signal
from CCD chip
Digital data
output
Exposure time
Figure 9-2