Redlake MASD 1.4i, Руководство пользователя

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REDLAKE MASD, INC.
4.8 Frame Rate Data
4.8.1 Frame Rates
The frame rate of the camera is the number of images that can be taken per unit time. The
camera must transfer a full frame before it is able to make a new exposure and transfer the new
frame. The rate depends on both the frame transfer time and the exposure time.
4.8.2 Frame Transfer Time
The frame transfer time is a constant. It is the number of pixels in a frame divided by the rate
they are clocked out.
1,037 lines x 1,394 clock intervals per line
= Transfer Time
10 MHz = 1,445,578 pixels @ 10 MHz
= 144.6 milliseconds
4.8.3 Frame Repetition Rate
The frame repetition rate depends on both the frame transfer time and the exposure time.
1 = Frame Rate
(Exposure time + frame transfer time + 1 idle line time + shutter transit time)
For exposures that are much shorter than the frame transfer time and when the shutter is off, the
frame transfer time dominates the above equation and the frame rate approaches the maximum:
1/(145) milliseconds = 6.9 frames per second
For an exposure time of 50 milliseconds, the frame rate becomes:
1/(145 + 50 + 15) milliseconds = 5.1 frames per second
For an exposure time of 200 milliseconds, the frame rate becomes”
1/(145 + 200 + 15) milliseconds = 2.9 frames per second
It is important to remember that each line has 1,317 active pixels and that there are 1,035 lines of
valid video data in each frame. The first and last lines are not light sensitive.
91000050-002 Revision A 4-10 10/01/01