title: Optical zoom camera module using two poly-dimethylsiloxane deformable mirrors.
abstract: Miniaturization is an essential trend in the design of portable devices. Motor-driven lens technology is a traditional way to achieve autofocus and optical zoom functions. This approach usually requires considerable space and consumes significant power. Reflective optics is a methodology that not only can fold the optical path, but it has the advantage of low chromatic aberration. In this paper, we use a deformable mirror as a reflecting element in an optical zoom system. For its low Young's modulus and residual stress, we choose polydimethylsiloxane as a deformable membrane that can provide a large stroke. The optical zoom module consists of a pair of micromachined deformable mirrors. The thickness of this module is 10 mm, which enables 2× optical zoom. The smallest effective focal length is 4.7 mm at a full field angle of 52°, and the f-number is 4.4. The largest effective focal length of the module is 9.4 mm, and the f-number is 6.4.
authors.forename: Yu-Hung
authors.initials: YH
authors.lastname: Huang
authors.forename: Hsiang-Chun
authors.initials: HC
authors.lastname: Wei
authors.forename: Wei-Yao
authors.initials: WY
authors.lastname: Hsu
authors.forename: Yuan-Chieh
authors.initials: YC
authors.lastname: Cheng
authors.forename: Guo-Dung John
authors.initials: GD
authors.lastname: Su