COHU 7700-2 SERIES 1004 X 1004, Technical Reference Manual

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6X-1029C
7700-2
TECHNICAL REFERENCE
Table 11. Operating Modes
ITEM MODE DESCRIPTION
1 VIDEO MODE
Continuous (Full Resolution) Free Running at 30 frames per second (30 fps)
Continuous (Partial Readout) Free Running
Snap Shot: Captures single image when triggered
2 VIDEO RATE
Continuous: 30 fps
Snap Shot: Maximum frame rate determined by exposure time and readout
time. Faster frame rates may be achieved using Partial Readout mode at the
expense of resolution
3
EXPOSURE
CONTROL
High Speed Implicit Shutter: 1/60 sec to 1/25,000 sec in 10 steps
Multiple Lines Explicit Shutter: Exposure time adjustable by number of line
intervals (33.3 µs) from line 1 to 65,000 lines
Multiple Frames: Exposure time adjuatable by number of frame intervals (33.3
ms) from 1 frame to 65,000 frames
Note: Multiple Lines exposure of 1004 = Multiple Frame exposure of 1
External Shutter: Exposure time determined by Pulse Width of an externally
applied trigger pulse (Async Snap Shot mode only)
4
GAIN & OFFSET
CONTROL
Gain Control:0-30 dB. Setting values from 0 to 320 via serial command
Offset Control: Video Black level adjustment: 0 to 1023 via serial command
5 SNAP SHOT MODES
Snap Shot imaging may be accomplished either by applying an external trig-
ger pulse to camera or by giving the camera a serial command.
ASYNC SNAP SHOT. Maximum Frame Rate is determined by exposure time
and readout time. A new trigger may not be applied until readout of previous
image is complete. Readout time = [(number of lines read out ) + (number of
lines dumped) / 4] x 33.2 µs
• Async Snap Shot (Internal Exposure Modes): Exposure is initiated by falling
(leading) edge of an external trigger pulse or by serial command. Exposure
time is determined by camera exposure mode (MultipleLines / MultipleFrames)
Async Snap Shot (External Exposure Mode): Exposure is initiated by the fall
-
ing (leading) edge on an external trigger pulse or by giving a Start exposure
command. Exposure is ended by the rising (trailing) edge of the exterenal trig-
ger pulse or by giving an End exposure command.
SYNCHRONOUS SNAP SHOT Maximum Frame Rate is determined by read-
out time. Trigger may be applied during the readout of previous capture frame,
but previous readout must complete before end of the triggered exposure time.
Readout time = 33.3 ms (Partial readout is not available in this mode). Maxi -
mum frame rate can approach 30 fps.
• Synchronous Snap Shot (Internal Multiple Lines Mode Only): Exposure
begins with the first Horizontal Drive pulse following the leading edge of an
external trigger pulse or following receipt of a serial command. Expsure time is
determined by camera exposure (Multiple Lines) setting. Readout begins with
the next horizontal drive pulse following CCD transfer. (Minimum of 50 Line
Exposure setting).
Continued