JAI CV-A11 operation manual Pulse Width Control Mode, Pulse width control

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CV-A11

6.6. Pulse Width Control Mode

The leading edge of the trigger pulse initiates the capture. The exposure time (accumulation time) is governed by the duration of the trigger pulse. If the polarity of this pulse is reversed, the camera can be configured to correct for it.

The exposure time range is 1.5H to 1000H (shortest and longest pulse duration).

To use this mode:

 

 

Set function:

Trigger mode to “Pulse Width Control”

TR=2

 

HD accumulation

HC=0, HC=1

 

Polarity and other functions

 

Input:

Ext. trigger to pin 5 on 6 pin connector (or 11 on 12 pin connector)

 

Ext. HD to pin 6 on 12 pin connector. (If used).

 

Fig. 18. Pulse width control.

Important notes on using this mode:-

The exposure will start and stop synchronized to the internal H signal. It result in 1H jitter. To avoid this jitter, synchronize the camera with an external HD and make sure that the trigger pulse aligns to the HD signal as shown in Fig. 14.

This trigger mode is also supported by a function called “HD Asynchronous Accumulation”, ACSII command “HC”. This function allows integration to start immediately at the leading (falling) edge of the Ext. Trig pulse instead of at the next horizontal drive pulse HD. Please refer to fig. 15 and fig. 16. To enable this function, set HC=1. (Factory default is HC=0). If the falling edge of the trigger falls inside the HD low pulse, a jitter up to 7.5sec. can be expected. The exposure will start up to 7.5sec. after the falling edge of the trigger.

In HD asynchronous PWC mode avoid the trigger to raise inside the HD low period. It will cause 1 line image position jitter.

Please note that the timing chart in Fig. 18 only shows the HD synchronous mode.

Do not input external VD signal at Pin No. 7 of the 12-pin Hirose connector, as it may disturb the external trigger function.

Do not input a new trigger before the previous video is read out. (WEN is high).

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Contents CV-A11 CV-A11 Table of ContentsStandard Composition Main FeaturesGeneral Camera Housing and Dimensions Pin Assignment Pin Multi-connector DC-IN/VIDEO OUT, EXT.HD/VDPin Multi-connector Trigger and RS232C HD and VD input Input and Output CircuitsVideo output Trigger inputBasic functions Functions and OperationsContinuous Operation Non triggered Input-output of HD/VD SignalsEdge Pre-select Mode.TR=1 External Trigger ModesImportant notes on using this mode Edge Pre-select ModePulse width control Pulse Width Control ModeFrame delay read out Frame-delay read out ModeLong time exposure Long Time Exposure ModeStart/stop mode Start/Stop ModeSmearless mode Smearless ModeReadout format Frame rate Effective lines Partial scan readout modeOther Functions RS-232C control Configuring the CameraUseful commands CV-A11 RS-232C command listCamera Control Tool for CV-A11 1. HD/VD input-output selection Internal Switch and Jumper SettingsSelecting termination of HD/VD input signals Spectral Sensitivity SpecificationsCV-A11 emulating CV-M10 interfacing WEN out on pin 6 on 6 pin connectorAppendix Typical CCD Characteristics PrecautionsCamera type CV-A11 Revision Revision a Serial No …………… Users Record