Switches, holographic

The answer to this question has become even more important with the advent of modern liquid crystal display technologies, that are based on reliable and technologically controllable surface alignment of liquid crystals, used in a variety of electrooptic devices, such as liquid crystal displays, light modulators, optical shutters, switches, holographic systems, etc. 

Figure 6 Cross-section of a switchable grating from photoresist (Strategy 3). By using standard semiconductor fabrication techniques, a cell can be constructed with a holographically patterned central electrode. After filling with LC, the cell can be switched on and off with an electric field applied between the outer unpatterned electrodes.

The wideband holographic imaging technique is very sensitive because of the active, coherent, heterodyne detection that is employed in typical systems [15-17], Therefore, the primary limitation on image acquisition is the time required to mechanically scan the transceiver. Two-dimensional raster scans are often used for laboratory experiments, and these typically require scan times on the order of 1-30 min. Practical systems employing linear switched antenna arrays and mechanical scanning reduce this time to 1-10 seconds [15-17],... 

Figure 6 Block diagram of the two-color optical parametric amplifier (OPA) and IR-Raman apparatus. CPA = Chirped pulse amplification system Fs OSC = femtosecond Ti sapphire oscillator Stretch = pulse stretcher Regen = regenerative pulse amplifier SHGYAG = intracavity frequency-doubled Q-switched Nd YAG laser YAG = diode-pumped, single longitudinal mode, Q-switched Nd YAG laser KTA = potassium titanyl arsenate crystals BBO = /J-barium borate crystal PMT = photomultiplier tube HNF = holographic notch filter IF = narrow-band interference filter CCD = charge-coupled device optical array detector. (From Ref. 96.)...

Important facets are the understanding of interfaces between various materials, whether organic or inorganic the use of self-assembly and patterning techniques in production and the identification of new semiconductors, for example, carbon nanotubes. Furthermore, materials for information storage have also been addressed, such as holographic or new forms of switches (e.g., DNA, picosecond). 

---