Asking the right questions leads to best optical shutter design, writes Vincent’s Pasquarella
Electromechanical shutters are vital components in a broad spectrum of optical assemblies and systems. Shutter requirements are sometimes not apparent or considered during optical system design; other times, they need to be expanded upon after the launch of a system. Additionally, requirements may be added by the ultimate end user of a system that necessitate the implementation of a shutter into the design.
The perceived simple nature of a shutter (a device that opens and closes to gate light) leads to a tendency for its consideration to be left until later in the design cycle, or when a prerequisite of the design reveals a specified need. Such scenarios can potentially raise havoc with a product’s development cycle, especially if the nature of the design requires significant time to accomplish lifetime qualification, prove new material interactions, and/or develop special test equipment for the customer’s ongoing production qualification. For example, doing a lifetime-qualification test of a larger-aperture device such as a 65 mm shutter at a test rate of slightly greater than 1 Hz and a specified lifetime of 2.2 million operations can take more than 25 days to complete even for around-the-clock testing.
This article discusses a few cases where the system integrators/designers did not consider the need for a shutter device during the design pre-stages, resulting in project delays, costs adjustments, and additional testing. However, understanding certain criteria and asking a number of questions of the shutter-design team can help the design engineer to predict the need for a shutter early on and to allow for more consistent development and implementation.New York State Optics, Publications comment below, or link to this permanent URL from your own site.