Basic research on the optical Kerr effect seen in liquid crystals and its potential for use in liquid crystal over silicon technology.

• Applicant: Dr. Alexander Lorenz
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering ; Synthesis and Properties of Functional Materials
• Term: from 2012 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 220040763

Liquid crystal over silicon (LCOS) technology is quickly evolving in several markets ranging from adaptive optics to miniature projectors. Transparent liquid crystal displays are widely used in television screens, tablet PCs, and smart phones. However, transparent displays cannot be miniaturized arbitrarily. In contrast, LCOS technology allows for high resolution microdisplays. In order to display on large screens, LCOS micro¬displays are traditionally used in projecting devices, such as rear projection televisions where the LCOS-chip is based on intensity modulation. Additionally to intensity modulation, liquid crystals can also be used for phase modulation very efficiently. LCOS microdisplays can be used to achieve holographic projection of 2D and 3D videos with brilliant colors. Currently, LCOS devices based on phase modulating planar aligned nematic LCs are only capable of achieving rather slow frame rates.Liquid crystals can show faster electro optic effects. One of these effects is induced birefringence (Kerr effect). Although, the Kerr effect has been and currently is thoroughly investigated in transparent liquid crystal devices, these devices still suffer from high driving voltages. The proposed research project shows that LCOS-technology can benefit from the use of liquid crystals, which show the Kerr effect. For example, the process of fabricating LCOS devices is considerably simplified, because anchoring layers, which are required by alternative approaches, can be waived. Moreover, the use of such liquid crystals can lead to higher frame rates. Silicon technology is ideally suited in order to investigate, if smart electrode design can lead to lower driving voltages.

• DFG Programme: Research Fellowships
• International Connection: United Kingdom
• Host: Dr. Timothy D. Wilkinson