We propose an Eye Tracker/Display system, based on a novel, dual function device termed ETD, which allows sharing
the optical paths of the Eye tracker and the display and on-chip processing. The proposed ETD design is based on a
CMOS chip combining a Liquid-Crystal-on-Silicon (LCoS) micro-display technology with near infrared (NIR) Active
Pixel Sensor imager. The ET operation allows capturing the Near IR (NIR) light, back-reflected from the eye's retina.
The retinal image is then used for the detection of the current direction of eye's gaze.
The design of the eye tracking imager is based on the "deep p-well" pixel technology, providing low crosstalk while
shielding the active pixel circuitry, which serves the imaging and the display drivers, from the photo charges generated
in the substrate. The use of the ETD in the HMD Design enables a very compact design suitable for Smart Goggle
applications. A preliminary optical, electronic and digital design of the goggle and its associated ETD chip and digital
control, are presented.
A new technological solution for backside illuminated CMOS imagers is proposed. The pixel area consists of an n-well/
substrate photo diode and a deep p-well, which contains the APS pixel circuitry as well as additional application
specific circuits. This structure was analyzed using Silvaco's ATLAS device simulator. Simulation results show that this
structure provides low cross-talk, high photo response and effectively shields the pixel circuitry from the photo charges
generated in the substrate. The deep p-well pixel technology allows increasing the thickness of the die up to 30
micrometers, thus improving its mechanical ruggedness following the thinning process. Such deep p-well imager
structure will also be integrated into the Image Transceiver Device, which combines a front side LCOS micro display
with a back-illuminated imager.
In this presentation, several options for implementing an Image Transceiver System operating in real time are analyzed.
These include: the implementation of a multi chip system (including Display, Imager and Controller/Processor chips)
versus a single chip embedded system. The logical and physical aspects of a single chip, two chip- and three chip-implementation
are analyzed. The parallel and serial data transfer methods are analyzed for each case.
One of the key factors affecting the performance of liquid crystal devices is the fringing field effect. This effect is the principal cause for the current resolution limitations of LCDs as well as the reduction in both the maximum deflection angle and the diffraction efficiency of beam steering devices. Recent studies in the reduction of the fringing field effects will be presented with applications in the development of ultra-small pixel sizes in LCD's and high performance LC-beam steering devices. A particular implementation using Gires-Tournois structure will be discussed. Another area of research to be discussed is a study of the fundamental limits of LCs and other electro-optic materials, with respect to their electro-optic coefficient. Fundamental physical limitations based on material stability considerations will be presented.
System architecture has a significant impact on software performance. In this manuscript, a method to increase the performance of the microprocessors and FPGA based systems using pipeline processing, is presented. An improved implementation using this concept, for image and display processing, providing real time vision applications, is described.