Specifications

Chapter 2 Getting Started 21

exp

Shutter

Scan

= Shutter Compensation Time

= Readout Time

exp

= Exposure Time

Figure 6.

and SHUTTER MONITOR signals

Note: In frame-transfer operation, where the exposure cycle and readout

cycle overlap, the timing changes as discussed in Chapter 5 and the

system would not ordinarily include an operating shutter.

When the ST-133 or ST-133A is controlling a Princeton Instruments

intensified camera

, SHUTTER MONITOR has other functions. If

shutter-mode operation is selected at the IIC-100, IIC-200 or MCP-100

and there is no signal applied to the SHUTTER IN connector of the

IIC-100, IIC-200 or MCP-100, the intensifier is biased on continuously

and the detector “sees light” for as long as the high voltage is applied. If

the ST-133/ST-133A’s SHUTTER MONITOR output is applied to the

SHUTTER IN connector of the IIC-100, IIC-200 or MCP-100, the

intensifier can be turned ON or OFF in much the same way as it is in

gated operation, but at slower speeds, allowing exposures from 50 µs to

2.3 hours to be set from software.

In gated operation it is desirable that the intensifier be biased off when

the array is being read out to prevent artifacts from being coupled into

the video from the high-voltage switching. The Shutter Monitor signal

normally provides this function. With an FG-100 Pulser, this signal

would be applied to the pulser’s Enable input. With a PG-200 Pulser, it

would be applied to the pulser’s

input. With a DG535 Timing

Generator, Shutter Monitor is applied to the DG535’s Inhibit input.

BNC connector: After a Start Acquisition command, this output

changes state on completion of the array cleaning cycles that precede the

first exposure. Initially high, it goes low to mark the beginning of the

first exposure. In free run operation it remains low until the system in

halted. If a specific number of frames have been programmed, it remains

low until all have been taken, then returns high.

SHUTTER MONITOR is not required to inhibit the intensifier if using a PI-MAX camera

controlled by an ST-133A equipped with a PTG. With this combination, the inhibit function is

accomplished by selecting the Internal Sync mode (WinView/32 or WinSpec/32; Acquisition -

Experiment Setup - Timing - Timing Mode selection).