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Simultaneous Multicolor Imaging of Biological Structures with Fluorescence Photoactivation Localization Microscopy

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Modified SCR for optically actuated triggering.

W W Rice¹, R C Oldenborg, F B Wampler

¹Los Alamos Scientific Laboratory, Los Alamos, New Mexico 87545, USA.

The Review of Scientific Instruments

|March 1, 1979

Summary

This summary is machine-generated.

A new, inexpensive optical trigger synchronizes pulsed lasers with instrumentation using a modified SCR. This device offers fast response and low jitter, making it ideal for precise timing applications.

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Area of Science:

Optoelectronics
Instrumentation
Laser Technology

Background:

Synchronizing pulsed lasers with signal gathering instrumentation is critical for accurate data acquisition.
Existing triggering devices may be complex, expensive, or lack sufficient speed and precision.

Purpose of the Study:

To develop a simple, inexpensive, and optically actuated triggering device (optical trigger).
To achieve precise synchronization between pulsed lasers and signal gathering instrumentation.

Main Methods:

Modification of a commercially available Silicon Controlled Rectifier (SCR) for light-activated operation.
Characterization of the optical trigger's output pulse characteristics into a 50-Omega load.
Evaluation of the device's sensitivity across the visible and near-visible spectrum.

Main Results:

The optical trigger delivers pulses of 84 V (8.3-ns rise time, 3.5-µs width) or 42 V (6.2-ns rise time, 7-µs width).
The device exhibits a fast transit time of 2.2 ns and low jitter (<1 ns).
Sensitivity spans the visible and near-visible spectrum.

Conclusions:

The developed optical trigger is a cost-effective and high-performance solution for laser synchronization.
Its fast response and low jitter meet key criteria for an ideal optical trigger.
The device's performance is suitable for various applications requiring precise timing.