Liquid crystal light valve structures

An improved photosensor film and liquid crystal light valves embodying said film is provided. The photosensor film and liquid crystal light valve is characterized by a significant lower image retention time while maintaining acceptable photosensitivity. The photosensor film is produced by sputter depositing CdS onto an ITO substrate in an atmosphere of argon/H2S gas while maintaining the substrate at a temperature in the range of about 130 C to about 200 C and while introducing nitrogen gas into the system to the extent of not more than about 1% of plasma mixture. Following sputter deposition of the CdS, the film is annealed in an inert gas at temperatures ranging from about 300 C to about 425 C

Multi-Phase Gas Dynamics in a Weak Barred Potential

The structure of the interstellar medium in the central kpc region of a galaxy with a weak bar-like potential is investigated taking into account realistic cooling and heating processes and the self-gravity of the gas. Using high resolution hydrodynamical simulations, it is revealed that the resonant structures (e.g. smooth spiral shocks and a nuclear ring) are very different from those seen in past numerical models where simple models of the ISM, i.e. non-self-gravitating, isothermal gas were assumed. We find that the pc-scale filaments and clumps form large scale spirals, which resemble those seen in real galaxies. The fine structures are different between the arms and in the nuclear region. The next generation millimeter interferometer (ALMA) may reveal the fine structures of the cold gas in nearby galaxies. We also find a large scale anisotropy in the gas temperature, which is caused due to non-circular velocity field of the gas.The damped orbit model based on the epicyclic approximation explains the distribution of the hot (> 10^4 K) and cold (< 100 K) gases appearing alternately around the galactic center. Because of the temperature anisotropy, cold gases observed by molecular lines do not necessarily represent the real gas distribution in galaxies. Position-Velocity diagrams depend strongly on the viewing angles. As a result, the rotational velocity inferred from the PV maps could be two times larger or smaller than the true circular velocity.Comment: 7 pages, 8 figures, to appear in PASJ, vol. 56, no.6 (2001