Multispectral High Dynamic Range DMD-Based Scene Projector

ABSTRACT: OPTRA proposes the development of a three-band visible (VIS), shortwave infrared (SWIR), and midwave infrared (MWIR) high dynamic range digital micromirror device (DMD)-based scene projector incorporating OPTRA"s patented structured illumination technique for achieving low background scene projection and high contrast at high frame rates with the associated short integration times. This approach will use two source-conditioning DMDs operating in binary mode to illuminate three projector DMDs operating in either binary or PWM grayscale mode. One projector DMD is used for each spectral channel, and one source conditioning DMD is used for the VIS and SWIR channels and the other for the MWIR channel. Dichroics are used to produce a spatially registered total projected image which is high in contrast owing to the structured illumination and is also effectively analog owing to the binary illumination patterns which appear spatially grayscaled due to low pass spatial filtering by relay optics; these qualities are independent of frame rate and the associated integration time of the unit under test. The proposed solution also has a flicker-free mode where all DMDs are operated in binary mode. BENEFIT: The proposed solution offers high contrast, infinite bit-depth scene projection at high frame rates and over three spectral bands as well as excellent uniformity and 100% pixel operability. Applications include training and test of visible through midwave infrared imagers and threat detectors.