Fast exposure times - as short as 2 ms
Controlled via external TTL pulse, remote switch or RS-232
Synchronizing output signal
Compact size with 1.5 inch series flanges for easy mounting to detectors
This is our fastest family of electronic shutters; the shortest pulsewidth is 2 ms. We use them for laser pulse gating, precise exposure control, CCD frame transfers or simply to protect detectors from saturation. Exposures are highly repeatable and accurate; repetition rates are variable up to 150 Hz. The blades are coated with AlMgF2 for high reflectance (decreases the radiation absorbed on the input side); they are overlapped to prevent light leakage. Note, although the reflecting blades are not of optical quality, reflected beams can be hazardous. Ensure that reflected beams do not pose a safety hazard and do not retro-reflect into a sensitive laser source. Reflected radiation can destabilize many lasers. These shutters have a 1.5 inch series male mounting flange on the input side, and a 1.5 inch series female Quick Connect flange on the output. They couple directly to Oriel Detectors or Monochromator slit assemblies.
We offer three models of shutters and a stand alone driver to operate any of them. Note, the driver requires an external source of pulses.
Up to 150 Hz exposure frequency
6 mm aperture
The model 76992 is our fastest shutter. It is especially suited to laser or focal plane use and applications including beam modulation at frequencies up to 150 Hz.
Up to 40 Hz exposure frequency
14 and 25 mm apertures
These shutters are useful for detector protection and gating at frequencies of up to 40 Hz.
Fig. 1 The shortest pulse using the 76992 6 mm Shutter. The aperture was uniformly illuminated so the pulse rise and fall times include the large contribution from the outer zones.
Fig. 2 Using the 76992 6 mm Shutter to chop a 1 mm diameter laser beam. TTL pulses from a pulse generator with variable mark-space ratio allow independent control of pulse width and duration, within the specifications of the shutter.
The Shutter Driver, model 76995 , is required to operate any of these shutters. You must provide TTL pulses, from a Computer (RS 232 interface), from the 68945 Digital Timer, or other source. The 76995 enables the shutters to function as normally open or normally closed, and has three modes of operation.
The operating mode is largely a safety issue. If it is important to close the shutter and keep it closed if either power is lost and restored, or a system interlock failure is detected, you’ll need to run the 76995 in Line Interrupt or DC Interrupt Mode. If there is no concern then we recommend the Standard Mode of operation. The mode of operation is selected with the key switch. All modes give the same high shutter performance.
Exposure times are determined by an external pulse source or switch contact closure.
When power is lost, the unit is powered down; when power is restored, the unit must be reset to resume operation.
When a break is detected in the external switch contact, the unit is powered down; when power is restored, the unit must be reset to resume operation.
All Shutters can be triggered in four ways:
Manually using the normally open/close switch on the front panel of the driver
Externally applied TTL gate signal (such as from our 68945 Digital Timer)
Externally applied Open/Close TTL signal
RS-232 interface
The trigger type is determined by the speed and accuracy required of the shutter system. TTL signals provide the most precise control since the shutter drive mimics the input pulse. To synchronize the shutter to other computer driven equipment, without concern for precise timing of the shutter transitions, the RS-232 interface is convenient. If the shutter is to remain open and closed for long periods of time and there is no need to drive the shutter from an external event, use the manual open/close switch.
All shutters include a fast synchronizing sensor activated by a vane attached to the shutter blade. The sensor sends out a TTL signal when the shutter is greater than 90% open. The signal is available at a BNC connector at the rear of the controller.
For repeatable, timed exposures, order the 68945 Digital Timer. Note, the 76995 Driver is still required, to power the shutter. The OPS series power supplies may also be used for exposure times of 10 ms minimum.
The shutters have 1.5 Inch Series flanges and a 1/4-20 tapped hole in the bottom for rod mounting. An optical rod is not included.