39.1: Invited Paper: Why Analog Silicon May Be Best For LCOS Digital TV

Seemingly insignificant architectural silicon design choices can have a profound effect on both the performance and price of the liquid crystal on silicon (LCOS) device, and its optical system. The impact ranges from the obvious: silicon wafer yields and costs — to the not-so-obvious: lumen throughput, engine cost, die packaging costs, panel uniformity and greyscale bit-depth. Various LCOS panel architectures are compared. Through use of feature sizes, transistor densities, and die sizes — silicon backplane yields and thus die-level costs are estimated. Performance benefits such as greyscale reproduction, full-frame update, single-panel capabilities, pixel resolution and so forth are also compared. An estimate of total system price/performance is tabulated. These estimates indicate that analog backplanes (with digital interfaces, pixelated digital outputs, but continuous greyscale voltages optimized to liquid crystal voltage transfer curve) may currently offer best price with adequate performance for the rear projection television market.