Test vehicle for a wafer-scale thermal pixel scene simulator

A chip sized test vehicle has been created to experiment with the technology and design required for two wafer scale thermal pixel displays: a thermal pixel dynamic scene simulator and a visual-to-thermal converter. The 4.7×4.7 mm device contains a 2×4 array of micromachined thermal pixels, optical detectors, A/D converters, digital pixel control circuitry, and laser links for interconnection. Laser produced defect avoidance schemes allowed testing and harvesting for global redundancy of the control circuitry and local transducer substitution. Also the laser linked signal buses flexibility was used to arrange the chip in different thermal pixel display configurations. Two chips were laser interconnected, one as fabricated and another where anisotropic etching had created a suspended plate holding the polysilicon resistor thermal pixels. From the electrical and laser interconnection points of operation there was no difference between the etched and unetched circuits