Digital Mirror Device Research Articles

Electrostatic micromirrors for subaperturing in an adaptive optics system

An electrostatic digital mirror device has been used to replace the lenslet array in a simple adaptive optics system. Clusters of binary pixels define the subapertures of the image plane and direct a small portion of the image onto a detector. The detector measures position shifts in the focused subaperture image caused by optical aberrations. Measurements on a digital mirror-based system and a similar lenslet-based system compare favorably to within a simple scaling factor. A subaperture system designed around a digital mirror device could aid in the development of a sequential subaperturing method that would replace the more complex schemes used in traditional adaptive optics.

Image Light Amplifier (ILA) Technology for Large-Screen Projection

The paper describes the configuration and performance of Image Light Amplifier (ILA <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> ) projectors. The ILA projector combines the advantages of a CRT-type projector with the high brightness capability of a xenon arc lamp projection light source. The projector has no defined pixel structure such as that found on liquid crystal display (LCD) and digital mirror device (DMD) projectors. Thus, dynamic video images with continuous edges and a highly realistic image quality are projected. The ILA projector will directly accept all standard video and computer formats from PAL/NTSC at 15.625/15.750 kHz horizontal scan frequencies to work station formats at 90 kHz. The enabling technology of the projector is the Hughes-JVC ILA modulator, which accepts a low-intensity image from a cathode ray tube (CRT) and replicates the image on a high-intensity white xenon arc light beam. The ILA uses solid-state thin film and liquid crystal technology to create a compact, rugged, image light modulator. The ILA projector incorporates three ILA modulators for the RGB channels. Projectors with up to 12,000 lumens output, a contrast ratio of 1000:1, and a resolution of 2800 × 1500 TV lines are available. Two series of models, with one or three projection lenses, are available. Besides single-projector applications, such as electronic cinema, ILA projectors also are used in installations requiring high levels of raster shaping and the one-and two-dimensional seamless blending of multiple projector images.