JAI TM/TMC-4200CL Electronic Shutter, Preset Shutter, Programmable Exposure-Continuous Mode

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Functions and Operations

6.4 Electronic Shutter

The TM-4200CL has a substrate drain-type shutter mechanism which provides a superb picture at various speeds.

6.4.1Preset Shutter

TABLE 4. Electronic Preset Shutter

	Dual Tap		Single Tap
Shutter	Continuous	Async Mode	Continuous	Async Mode
Speed	Mode (sec)	(sec)	Mode (sec)	(sec)
0	No shutter	No shutter	No shutter	No shutter
1	1/60	1/16000	1/35	1/9000
2	1/125	1/8000	1/70	1/4500
3	1/250	1/4000	1/140	1/2250
4	1/500	1/2000	1/280	1/1120
5	1/1000	1/1000	1/560	1/560
6	1/2000	1/500	1/1120	1/280
7	1/4000	1/250	1/2250	1/140
8	1/8000	1/125	1/4500	1/70
9	1/16000	PWC	1/9000	PWC

6.4.2Programmable Exposure-Continuous Mode

The exposure time of TM-4200CL can be specified from one video line to a maximum of one frame using the serial communication commands in the Continuous Mode. There is overhead where the specified exposure time is n video lines, making the real exposure time equal to

Exposure Time=	{	(n+1) *32.5 μs+25.6μs	Dual Tap
		(n+1) *58.1 μs+25.6μs	Single Tap

When n=0, the exposure time is the minimum exposure time. It is equal to:

Minimum Exposure Time=	{	58.1 μs (1/17000s)	Dual Tap
		83.7 μs (1/12000s)	Single Tap

In this mode the maximum exposure time is equal to the setting for one frame. If the user specified exposure time is longer than the time allowed for one frame, it will be ignored by the camera.

6.4.3Asynchronous No Shutter Mode

In Asynchronous No Shutter Mode, applying the external trigger starts a camera scan reset. The camera finishes the line it is scanning and scans an additional 9 video lines, this charge is sent to the horizontal register.

Because the external trigger is randomly applied, the new image charge may overlap with the previous image. To prevent an existing charge accumulation from interfering with a new image, most users set up

TM/TMC-4200CL Series Progressive Scan Cameras