Optical Properties Of Bacteriorhodopsin Film And Their Applications

Optics and photonics have become the powerful support of information technique, industry, human life and other important aspects of modern society. bR film is one type of excellent nonlinear optical materials and has many outstanding properties such as large optical nonlinearity, high stability, low price and so on. In the thesis, we mainly studied theoretically and experimentally the nonlinear transmission properties, photo-induced grating, degenerate multi-wave mixing in bR film and their applications.The first chapter outlined the fundamental properties of bacteriorhodopsin materials, which include chemical structure, basic properties, especially the photocycle and the proton pump function of bacteriorhodopsin molecular, preparations of bR film and etc.. And we summarized the obtained results and future directions of research in bR material.Chapter 2 mainly studied the transmission properties of bR film and their application. It was derived the transmission equation of bR film under the simultaneous illuminations of purple light and yellow light based on the simplified two-state system, and the transmission properties of bR film were analyzed by using the numerical method. The calculated results showed there is a saturation absorption effect for yellow light transmission in the bR film. The thresholding intensity of yellow light is influenced by purple light and increases with the increase in the intensity of purple light. Parameters of bR film, such as density of bR film, lifetime of molecular in M state also influence the thresholding intensity of yellow light. According to the saturation absorption effect of yellow light and the modulation effect of purple light in bR film, for the first time we analyzed application of bR film in optical thresholding operations. And we realized the filter of bright background of pattern by winner-take-all operation in bR film, which can be used to improve the signal-to-noise ratio of input image with noise.bR film is one type of excellent real-time holographic materials. The third chapter discussed photo-induced gratings and degenerate multi-wave mixing in bR film. The photo-induced change in absorption coefficiency and in refractive index and their relationship were summarized. We studied experimentally the diffraction efficiency of normal gratings in bR film, and discovered for the first time that the diffraction efficiency depends on the intensity of writing beam and then explained it briefly. Photo-induced anisotropy and polarized hologram in bR film were discussed. The relationship among the...