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Mg[F.sub.2] films with a columnar microstructure are obliquely deposited on glass substrates by resistive heating evaporation. The columnar angles of the films increases with the deposition angle. Anisotropic stress does not develop in the films with tilted columns. The residual stresses in the films depend on the deposition and columnar angles in a columnar microstructure. OCIS codes: 310.6870, 310.4925, 310.1860.

Ta--Si oxide composite thin-film rugate filters were prepared by radio frequency ion-beam sputtering and their residual stress and substrate deflections were measured. The residual stress and substrate deflection of these composite film rugate filters were less than that of notch filters made from a series of discrete quarter-wave layers with alternate high and low indices because of the smooth modulation of composition and no interface structure of the rugate filter. OCIS codes: 310.6870, 310.1620.

Titanium oxide films were prepared by ion-beam-assisted deposition on glass substrates at various substrate temperatures. The effect of the temperature of thermal annealing from 100 [degrees]C to 300 [degrees]C on the optical properties and residual stress was investigated. The influence on the stoichiometry and residual stress of titanium oxides deposited at different substrate temperature was discussed. The residual-stress was minimum and the extinction coefficient was maximum at an annealing temperature of 200 [degrees]C with a substrate temperature of 150 [degrees]C. However, when the substrate temperature was increased to 200 [degrees]C and 250 [degrees]C, the residual stress was minimum and the extinction coefficient was maximum at an annealing temperature of 250 [degrees]C. The spectra of x-ray photoelectron spectroscopy reveal that the films lost oxygen and slowly generated lower suboxides at the annealing temperature at which the residual stress was minimum and the extinction coefficient was maximum. As the annealing temperature increased above the temperature at minimum stress, the lower suboxides began to capture oxygen and form stable oxides. [Ti.sup.O.sub.2] films deposited at substrate temperatures of 200 [degrees]C and 250 [degrees]C were more stable than films deposited at 150 [degrees]C. OCIS codes: 310.3840, 310.6860, 310.6870.

Titanium oxide thin films were deposited by electron-beam evaporation with ion-beam-assisted deposition. The effect of the substrate temperature and annealing temperature on the columnar microstructure and recrystallization of titanium oxide was studied. The values of the refractive index varied from 2.26 to 2.4, indicating that the different substrate temperatures affected the film density. X-ray diffraction revealed that all films were amorphous as deposited. At annealing temperatures from 100[degrees]C to 300[degrees]C, only the anatase phase was formed. As the substrate temperature increased from 150[degree]C to 200[degrees]C to 250[degrees]C, the recrystallization temperature fell from 300[degrees]C through 250[degrees]C to 200[degrees]C. Changing the substrate temperature resulted in the formation of various types of columnar microstructure, as determined by scanning-electron microscopy. Different columnar structures resulted in different surface morphologies, as measured by atomic-force microscopy. OCIS codes: 310.3840, 310.6860, 310.6870.

The effects of thermal annealing of titanium oxide films deposited by ion-beam assistance at annealing temperatures from 100 [degrees]C to 300 [degrees]C on the residual stress and optical properties of the films was investigated. The refractive indices and extinction coefficients increased gradually as the temperature was increased from 100 [degrees]C to 200 [degrees]C and then declined gradually as the temperature was increased further from 200 [degrees]C to 300 [degrees]C. The film lost oxygen and slowly generated lower suboxides as the annealing temperature was reduced below 200 [degrees]C, as determined by x-ray photoelectron spectroscopy (XPS). As the annealing temperature increased above 200 [degrees]C, the lower suboxides began to capture oxygen and form stable oxides. XPS measurements were made to verify both the binding energy associated with the Ti 2p line and the variation of the O 1s line. A Twyman-Green interferometer was employed for phase-shift interferometry to study the residual stress. The residual stress declined as the temperature was reduced from 100 [degrees]C to 200 [degrees]C because the lower suboxides reduced the stress in the film. Above 200 [degrees]C, the film began to capture oxygen, so the residual stress rose. At 300 [degrees]C, the film was no longer amorphous as the anatase was observed by x-ray diffraction. OCIS codes: 310.3840, 310.6860, 310.6870.

Both three-layer (Ti[O.sub.2]-Ag-Ti[O.sub.2]) and five-layer (Ti[O.sub.2]-Ag-Ti[O.sub.2]-Ag-Ti[O.sub.2]) heat mirrors with optimum transmission in the visible and good reflectance in the IR have been designed by admittance diagram techniques. The mirrors were fabricated successfully by optical monitoring. An interesting anomalous layer was found and explained, and its equivalent refractive index and thickness are 2.015 - i0.016 and 2.56 nm, respectively. Key words: Transparent heat mirror, optical monitoring, admittance diagram, ion-assisted deposition, anomalous layer.

An aspherical mirror is made by a thin-film coating technique. A special mask is placed between the evaporation source and the substrate that is to be coated as an aspheric. The design principle of the mask is fully described. An ion-assisted deposition technique is used to relieve aluminum film stress and to increase surface reflectance. The final wave front is tested by conventional interferometric methods for aspherics. Less than one-fifth of a wave (632.8 nm) of spherical aberration is achieved without much trial and error.