JAI TM-6740GE, Руководство пользователя

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Operation 23
TM-6740GE Series
The video signal starts with internal VINIT. When the external VINIT pulse is applied, internal VINIT is latched
to HD and the internal VINIT is delayed to set up the shutter speed period. The shutter speed is controllable by
the user via communication software. Video output timing starts right after the internal VINIT and single shots,
FDV is output at the internal VINIT timing.
3.6.3 External VINIT With Pulse Width (No-Delay Shutter) and ROI (Read-out Inhibit)
For multiple-camera applications such as 2D or 3D measurement and multi-angle inspection, simultaneous
image capturing at an exact shutter timing for all cameras is a critical requirement. The TM-6740’s
asynchronous pulse-width control mode provides no-delay shutter (Figure 10, “Pulse Width Control No-Delay
Shutter” on page 23) as standard. Regardless of the internal pulse timing, the camera discharges at the VINIT
leading edge and transfers charges at the trailing edge of the pulse. Even though each camera runs with slightly
different H and data clock timing, the image capturing is exactly simultaneous.
Figure 10. Pulse Width Control (No-Delay Shutter)
The TM-6740GE camera also has read-out-inhibit control (ROI) to control the vertical clock start (Pulse Width
Control mode). The ROI signal is fed in via the Integration Signal pin (External_INT_In). When ROI is low, V-
clock is stopped and the transferred charges remain in the vertical shift registers, which work like CCD
memory. When the ROI is high, it clocks out the CCD data. This helps a single frame grabber process multiple
images in pipeline processing (sequential process).
Note: When the ROI function is not used, make sure that the INTEG/ROI input is kept logic high during Async.
Pulse Width control mode. This done via the Programmable Logic Controller (See IP Engine Examples
section 5.8.8).