Methodologies for Developing Extremely Large IR Scene Projectors

We propose further developing very large LED arrays for IRSP applications. Our Phase I effort has demonstrated the feasibility of LED arrays of up to 2048x2048 pixels. In this effort, we seek to further increase the resolution of these arrays by developing technologies that will permit smaller pixels and physically larger arrays. We will also work to improve the electrical to optical conversion efficiency of these arrays by optimizing the number of quantum wells to match the RIIC capabilities. We also propose exploring methods of shifting to longer wavelengths with Type-I LED by utilizing a triple layer quantum well architecture. Finally, we will explore the potential for cascading multiple active regions for longer wavelength LEDs. The array design will also be improved, with changes made to improve efficiency by reducing surface recombination and by increasing thermal conductivity to the RIIC. A process for high yield flip-chip hybridization will be developed and studies regarding the expected yield will be conducted on custom made passive RIIC substitutes that will permit individual control of selected pixels within the array and group control of the remaining pixels.