Devices for optical information

One of the most important functional elements in devices for optical information processing is the transparency (or page composer). It organizes the information in the form of an optical image which can be recorded on... 

A possible limitation of ECDs and EWs is the relatively slow response time, which is typically in the range of a few seconds. This makes ECDs uncompetitive with LCDs for fast devices, such as electronic watches. However, if the applications are directed to realisation of large panels for optical information or for energy control, the time of response becomes... 

Triarylmethane Dyes with Near-Infrared Absorption. The long wavelength absorption bands of triarylmethane dyes can be shifted into the near-infrared region, but the dyes still remain colored because other absorption bands are shifted to or stay in the visible region. These types of triarylmediane dyes and their derivatives have been claimed as infrared absorbers for optical information recording media and security devices, and as organic photoconductors for nse in lithographic plate production. 

Various matrix addressing schemes are possible with two- and three-terminal devices. For more information, the reader is referred to an early paper of the RCA group (Lechner et al., 1971). Matrix addressing differs from multiplexing in that the LC can be driven at 100% duty factor, maintaining superior optical performance. 

Optically bistable devices are of considerable interest for information storage and processing applications. Bistable Fa-bry-Perot resonators [104] may be useful as dynamic optical memories as well as elements for information processing. Optically sensitive alignment layers [62], as well as a wide variety of laser addressable materials [105-107] promise the use of liquid crystals as materials for optical information storage. 

One of the important advantages of using the MIS device for optical measurements is that it allows quantitative measurements in the optical response, and we can gain very direct information about the way in which charge is stored in the device. Figure 32 shows the differential capacitance,C = d( V, for the device shown in figures 26,27,30 and 31 as a function of bias voltage and also the variation of 9ln(T)/9T, where T is the optical... 

FiaaHy, the use of photoreversible change of the circular dichroism for optical data storage is of iaterest. This technique offers an advantage over photochromic materials ia that the data can be read ia a way that does not damage the stored information. These chirooptic data storage devices have been demonstrated with the example of chiral peptides with azobenzene side groups (155). 

The work described in this paper is an illustration of the potential to be derived from the availability of supercomputers for research in chemistry. The domain of application is the area of new materials which are expected to play a critical role in the future development of molecular electronic and optical devices for information storage and communication. Theoretical simulations of the type presented here lead to detailed understanding of the electronic structure and properties of these systems, information which at times is hard to extract from experimental data or from more approximate theoretical methods. It is clear that the methods of quantum chemistry have reached a point where they constitute tools of semi-quantitative accuracy and have predictive value. Further developments for quantitative accuracy are needed. They involve the application of methods describing electron correlation effects to large molecular systems. The need for supercomputer power to achieve this goal is even more acute. 

The technique is referred to by several acronyms including LAMMA (Laser Microprobe Mass Analysis), LIMA (Laser Ionisation Mass Analysis), and LIMS (Laser Ionisation Mass Spectrometry). It provides a sensitive elemental and/or molecular detection capability which can be used for materials such as semiconductor devices, integrated optical components, alloys, ceramic composites as well as biological materials. The unique microanalytical capabilities that the technique provides in comparison with SIMS, AES and EPMA are that it provides a rapid, sensitive, elemental survey microanalysis, that it is able to analyse electrically insulating materials and that it has the potential for providing molecular or chemical bonding information from the analytical volume. 

ISBN 0819441783 Proceedings of SPIE — The International Society for Optical Engineering, 4991 45-63 Nanoelectronics and Information Technology Advanced Electronic Materials and Novel Devices, pp.915-931... 

Colloidal crysfals can be viewed as the mesoscopic counterpart of atomic or molecular crystals. They have been used to explore diverse phenomena such as crystal growth [52-54] and glass transition [55,56], and have many interesting applications for sensors [57], in catalysis [58,59], advanced coatings [60], and for optical/electro-optical devices for information processing and storage [61,62]. In particular, their unusual optical properties, namely the diffraction of visible light and the existence of a photonic stop band, make them ideal candidates for the development of photonic materials [61,63-66]. They may lead to the fabrication... 

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