Spatial-frequency response of holographic gratings photodeposited from inorganic colloids.
Surface photodeposition is a photon-assisted process by which thin films are formed on substrates immersed in colloid solutions. We experimentally evaluate the resolution capabilities of the photodeposition process with amorphous selenium colloids by recording holographic gratings at different spatial frequencies, up to 2200 lines/mm. The experimental diffraction efficiencies are analyzed in terms of a theoretical model, which relates the spatial-frequency response to optical recording parameters and colloid particle sizes. The maximal experimental diffraction efficiency reaches 13% with a spatial frequency of f = 1100 lines/mm. The diffraction efficiencies decrease monotonically with spatial frequency, and drop to half of the maximal diffraction efficiency at f ≈ 1500 lines/mm. These resolution capabilities are achieved with colloid particle sizes extending up to 80 nm. The theoretical derivation indicates that to obtain spatial frequencies above 3000 lines/mm, one should restrict the colloid particle size to a(max) ≤ 30 nm.
Continuous-wave laser photodeposition of amorphous selenium films
The photodeposition of amorphous selenium films by continuous-wave argon ion lasers has been investigated. The deposition features of the process were recorded by measuring the variations in the diameter of the photodeposited beam spot as a function of the time, the laser beam power and its spectral lines. It was found that the pre-deposition incubation periods τ obtained by 10 W laser beam irradiation are of 30 s or less for areas of about 14cm2. The kinetics of film growth are of the logarithmic type and resemble the results obtained with low optical power excitation from incoherent light sources. The photodeposition spectral sensitivity increases by a factor of 103 in the wavelength region 450–500 nm. It was proven for the first time that photodeposition may occur on any solution discontinuity interface, allowing simultaneous photodeposition on several surfaces in a back or forward orientation with respect to the incoming light beam.
Metallurgical Process Engineering
The "material of choice" - steel.- Uprising of China's steel industry.- Process manufacturing industry and process engineering.- Engineering science in steel manufacturing process.- Analysis and integration of metallurgical manufacturing process.- Multi-dimensional mass flow control for metallurgical manufacturing process.- Time factors in steel manufacturing process.-Operating dynamics in the production process of steel plant.- Structure and mode of steel plant.- Steel plant and environment.