Optical information recording media

Ai- 4-(bis[4-(phenylamino)phenyl]methylene)-2,5-cyclohexadien-l-ykdene -3-methyl-ben2eneaminesulfate [57877-94-8] (20) have been claimed as positive CCAs (65). The absorption spectra of the triaryknethane dyes can be extended into the near-infrared region. The use of triaryknethane dyes as infrared absorbers for optical information recording media (66) and as infrared color formers in carbonless copy paper has been claimed. 

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. 

Sensors, Light-Emitting Devices and Optical Information Recording Media... 

Dextrin is extensively used in the manufacture of photosensitive materials (developers, thermal recording materials, optical information recording media, and photohardenable printing and transfers). Among other uses, dextrin diminishes the absorptivity and flabbiness of diazo copying... 

H. Horimai, Y. Sakane and K Kimura, "Optical information-recording medium, optical... 

Jung, J. H. Lee, K. H. Yang, C. S. Synthesis and physical properties of cyanine dyes as optical information recording medium. J. Korean Chem. Soc. 1998, 42, 570-574. 

J. Miyazaki, E. Ando, K. Yoshino, and K. Morimoto, Optical high density recording mediums, method for making same and method for recording optical information in the medium, U.S. Pat. 4,737,427, 8 pp., Apr. 12, 1988. 

An analysis of the properties of photochromic quinones shows that the main potential field of their applications is a light-sensitive medium for recording, multiplying, storing, and processing optical information. 

RAM is a form of computer data storage. RAM takes the form of ICs that allow stored data to be accessed in any order (i.e., at random). The word random thus refers to the fact that any piece of data can be returned in a constant time, regardless of its physical location and whether or not it is related to the previous piece of data. RAM is a volatile type of memory, where the information is lost after the power is switched off. By contrast, storage devices such as magnetic discs and optical discs rely on the physical movement of the recording medium or a reading head. In these devices, the movement takes longer than data transfer, and the retrieval time varies based on the physical location of the next item. 

The structures that have evolved for ablative-mode optical discs make use of interference effects to minimize the reflectance (R) of the disc in the absence of a hole. A typical ablative-mode optical disc has the structure shown in Figure 5.51. The substrate is an optically transparent material such as polycarbonate, poly(methyl methacrylate), poly(ethylene terephthalate), or poly(vinyl chloride), topped by a subbing layer to provide an optically smooth (to within a fi-action of a nanometer) surface for the recording layer. A metal reflector (typically aluminum) is then incorporated next to a transparent dielectric medium such as spin-coated poly(a-methyl styrene) or plasma-polymerized fluoropolymers. This dielectric spacing layer serves both to satisfy the quarter-wave (2/4) antireflection conditions and to insulate thermally the A1 reflector from the top absorbing layer where the information pits are created. 

There are many practical microelectronic device configurations that are based on epitaxial semiconductor thin films. Heteroepitaxial thin films are also used in magnetic recording media, such as computer hard disks an example is described in Section 1.4.4. Epitaxially grown multilayer structures are also used in planar array laser diodes, which serve as optical inter-connnects for short- and medium-range information transfer, and which offer potential for the development of new devices for such applications as solid... 

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