Presentation: Camera Mount Failure in Harsh Environments

Temperature swings in harsh environments wreak havoc on cameras and their optical performance. Research shows that the lens mounting structure is critical to ensure lens systems remain robust even when temperatures have a wide range.

Eric M. Schiesser from Synopsys, Inc. will present the new research on the topic at the Optica Design and Fabrication Conference, June 4-8, 2023, in Quebec City, Canada. The focus of the design study is how interwoven the mounting structure is to the optical prescription.

Both the lens glass and materials used to create the mounts that hold lenses are sensitive to changes in temperature. It is possible to reduce variations in optical performance over a range of temperatures using a process called athermalization that achieves optothermal stability by incorporating several materials with different thermal properties.

Researchers focused on passive athermalization to mitigate thermal effects, designing the lens system and mounting structure so that the thermal shift of the optimal focal plane matched the mechanical shift of the focal plane array used as the detector in the camera. They then tested the same camera lens with two mounting structures.

A performance comparison for the different mount configurations showed that when they changed the mounting method, the focal plane array was out of sync with the optimal image plane as lens elements don’t respond to temperature changes in the same way. The researchers note that this performance degradation is not inherent to a spacer-based mounting structure. If the original athermalization was carried out assuming spacers, switching to seats would also degrade the performance.

Visit https://www.optica.org/en-us/events/congress/optical_design_and_fabrication_congress/ for more information on the Optica conference.