Objectives

A. Applications

The first major class of applications is (flight) simulation, characterized by high contrast ratio and fast response time requirements, as well as the need for a compact form factor.

A second class of applications is aimed at Presentation and Virtual & Augmented Reality systems, including Digital Cinema. These applications require high light outputs but are allowed to have a larger form factor.

A third class of applications is medical imaging. A high effective contrast ratio is required in typical office ambient light conditions (which implies a high light output). Since medical images are typically grayscale images a neutral gray color is required from dark to bright grayscales.

B. Silicon processing

The main challenge from silicon processing point of view is the expected die size of the LCOS display.  4kx2k pixels have to be placed on the display area surrounded by logic circuitry. We can expect chip diagonals exceeding the maximum diagonal allowed by the lithographic equipment. To build such a big die, it has to be constructed by several lithographic shots. This technique is known as "Stitching".

One objective is the development of a fast stitching technology suitable for small volume production.

Another objective is to develop design rules or transformation algorithms for chip layout generating software tools that are tolerant for the stitching seam areas and take into account overlay area effects such as line width variations.

To comply to the extremely high quality demands of the envisaged applications, a reduction of micro and macro range in-homogeneousness of the chip topology is targeted.

Finally, an integrated spacer technology will be developed, taking into account the interaction with the alignment layer process.

C. Liquid crystal assembly and liquid crystal mixtures

An LCOS technology will be developed that is

a) adapted to large active matrix diagonals
b) is certified for high light fluxes and related issues and
c) exhibits high switching speeds.

Both existing LC mixtures and newly developed mixtures will be used to target these objectives.

D. Backplane and electronics design

The first challenge is to develop a very small pixel circuit, so that the resulting LCOS imager is compatible with manufacturable optical engines. Several pixel architectures will be investigated.

The second challenge is the use of stitching and its implications for the design.

The third objective is the design of an integrated driver circuit capable of refreshing the 8.8 million pixel device at 120 Hz. 

E. Packaging

The main challenge for the package is to deal with the heat generated by the enormous required light output. Standard packages are not suited for the targeted high light fluxes where a lot of heat has to be removed from the imager. Therefore a novel custom-made LTCC (low temperature co-fired ceramic) package will be developed within this project. .

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