Spatially Controlled Opto-Fluidic Attenuator

ABSTRACT: Glint Photonics proposes to develop the Spatially Controlled Opto-Fluidic Attenuator (SCOFA), a new type of optical element that can addressably and selectively block incoming light over arbitrary areas. The SCOFA is an array of shutter pixels, each of which contains a small droplet of liquid metal. Electrowetting actuation is used to draw the metal droplet into a thin flat channel, spreading it out to form an opaque shutter that reflects incident light. When the bias is removed, interface tension causes the liquid metal to recoil back into a droplet shape, re-opening the light valve. Liquid metal is an attractive material for shutter applications because it offers complete blocking of broadband light sources in a very thin film. Electrowetting actuation is expected to provide a facile means of switching the light valves. Phase I research will evaluate different electrowetting approaches and explore pixel design geometries BENEFIT: The Spatially Controlled Opto-Fluidic Attenuator (SCOFA) is designed to improve the imaging capabilities of airborne and space-based camera sensors in sun-facing orientations or high-glare situations. Optical sensors have a limited dynamic range, so the presence of bright sources in the field of view can prevent the sensor from resolving other, dimmer, elements in the scene. By selectively blocking out the light from bright sources, the SCOFA will allow sensors to devote their full dynamic range to the remainder of the scene. The ability to provide high-quality data in these difficult imaging conditions would expand intelligence-gathering and targeting capabilities, allowing US forces to operate with greater speed, flexibility, and accuracy. Numerous other applications are also possible, in both military and civilian uses. Airborne imagers are increasing used by domestic law enforcement agencies, and also find application in agriculture, forestry, and other fields. Each of these applications could benefit from the SCOFA in order to provide better imagery in high-glare situations. At sufficiently low price-points, the SCOFA could even be integrated into consumer cameras to provide spatially-controlled glare-suppression or to replace costly and delicate mechanical shutters.