512X512 INFRARED CRYOGENIC SCENE PROJECTOR ARRAYS

A mosaic array of resistively heated microbridges offers much flexibil ity for infrared scene simulations. Dynamic scene simulations are impo rtant for the testing of the real-time performance capability of IR ca mera and seeker systems. The excellent thermal properties of the emitt er pixels achieved with thin films and unique thermal isolation struct ures make it possible to achieve high temperatures at power levels app roximate to 1 mu W per pixel per degree temperature rise. High radianc e and high dynamic range are achieved by having pixels with high emiss ivity and high fill factors, which operate with the substrate and driv e electronics at cryogenic temperatures to achieve low background radi ance. The thermal time constants of the pixels are defined by material properties and pixel design and are in the millisecond range, making it possible to achieve dynamic frame rates in excess of 100 Hz. Two ty pes of cryogenic resistor arrays have been fabricated and are describe d, 512x512 arrays with pixels on a 3.5 mil pitch, and 128x128 arrays w ith pixels on a 2 mil pitch.