8 December 2004 Novel high-bandwidth bimorph deformable mirrors
Author Affiliations +
Adaptive Optics (AO) is a critical underpinning technology for future laser delivery (including free-space optical communications), target illumination and imaging systems. It measures and compensates for optical distortion caused by transmission through the atmosphere, resulting in the ability to deploy smaller lasers and identify targets at greater ranges. One of the key components in an AO system is the wavefront modifier, which acts on the incoming or outgoing beam to counter the effects of the atmosphere. BAE SYSTEMS Advanced Technology Centre is developing multi-element bimorph deformable mirrors for such an applications. Our initial designs were based on a standard construction and exhibited a resonant frequency of 1kHz with a maximum stroke of ±20μm for an active aperture of 50mm. These devices were limited by the necessity to have a 'dead space' between the inner active area and the mirror boundary; this ensured that both the requirements for the stroke and the fixed boundary conditions could be met simultaneously. However, there was a significant penalty to pay in terms of bandwidth, which is inversely proportional to the square of the full mirror diameter. In a series of iteration steps, we have created novel mounting arrangements that reduce dead space and thus provide the optimum trade-off between bandwidth and stroke. These schemes include supporting the mirror from underneath, rather than at its edge. As a result, models of 60mm active diameter mirrors predict a resonance in excess of 5kHz, combined with a maximum stroke greater than ±40μm. This paper will discuss a number of different mirror designs and present experimental results for recently assembled devices.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Michael S. Griffith, Michael S. Griffith, Leslie C. Laycock, Leslie C. Laycock, Nick J. Archer, Nick J. Archer, } "Novel high-bandwidth bimorph deformable mirrors", Proc. SPIE 5614, Advanced Free-Space Optical Communications Techniques and Technologies, (8 December 2004); doi: 10.1117/12.578202; https://doi.org/10.1117/12.578202


High-bias membrane mirror
Proceedings of SPIE (January 12 1992)
System-level simulation of micromirrors for adaptive optics
Proceedings of SPIE (January 29 2003)
Dual-use bimorph deformable mirrors
Proceedings of SPIE (November 03 2005)

Back to Top