- Email: [email protected]
169. Optical constants of evaporated se films by successive approximations
236
Abstracts 167-177
process and the bimolecular recombination process. This equilibrium condition permits predictions of the dependence of the emission intensity, the efficiency, and other properties on several parameters such as the voltage, the temperature, and the concentrations of electron traps and activator centers. These predictions are compared with experimental results. (Author) Willi Lehmann, J. Opt. Soe. Amer. 48, No. 9, 647-653, Sept. 1958. 19 : 30 : 51 167. Reflexion Coefficient of Optically Inhomogeneous Layers. The reflexion coefficient is calculated for radiation incident normally on a non-absorbing, optically inhomogeneous, plane parallel layer bounded on either side by non-absorbing semiinfinite media. The theory is applied to determine the reflectance of a layer in which the index of refraction varies nearly linearly with the thickness. (Author) Joseph F. Hall, Jr., J. Opt. Soc. Amer. 48, No. 9, 654-657, Sept. 1958. 19:30 168. Optical Transmission of Evaporated IN, SN, and BI Films in the Vacuum Ultraviolet. W. C. Walker, O. P. Rustgi and G. L. Weissler, J. Opt. Soc. Amer. 48, No. 12, 1017, Dec. 1958. 19 : 30 169. Optical Constants of Evaporated Se Films by Successive Approximations. Experimental values of the refractive index ~ and the absorption constant k in the wavelength range 0.24 to 2.5 microns are reported for evaporated films of Se. Methods of successive approximation were used to obtain an average precision of ± 0.003 in the non-absorbing region and ~ 0.005 in the absorbing region. Electron microscope and electron diffraction techniques indicate that the Se films were amorphous and non-porous. (Author) W. E. Koehler, F. K. Odencrantz and W. C. White, J. Opt. Soc. Amer. 49, No. 2, 109-115, Feb. 1959. 19:30 170. Optical Properties of Various Evaporated Rare Earth Oxides and Fluorides.* To furnish a greater choice of film materials for application in optical multilayer coatings, the optical properties of evaporated rare earth compounds such as Y203, La6Oll, Pr203, Nd2Oa, Sm~Oa, LaF3, NdF3, and CF3 were studied in the wavelength region from 0.22 t~ to 2 tz. The materials were evaporated from tungsten boats and condensed on glass and fused quartz substrates at various temperatures. The optical constants n and k were determined mainly from reflectance, transmittance, and true thickness measurements. The following oxides were found to be useful because of their low absorption in the visible : La203 with n ranging from 1.85 to 1.95 with increasing thickness, Pr6011 with n ranging from 1.92 to 2.05, also with increasing thickness and Nd2Oa with n = 2.05 for films of sufficiently low absorption. LaF3 (n = 1.60) and NdFz (n = 1.61) showed no appreciable absorption in the whole wavelength region studied ; CeF3 (n = 1.63), however, exhibited two weak absorption bands at 0.234 and 0.248 t~. All n values are given at a wavelength of 0.5 tL and for unbaked films deposited at 300°C substrate temperature. The oxides condensed as almost amorphous films, whereas the fluorides developed fairly large grains as indicated by their sharp electron diffraction rings. All films were hard and showed excellent chemical and mechanical durability. (Author) G. Hass, J. B. Ramsey and R. Thun, J. Opt. Soc. Amer. 49, No. 2, 116--120, Feb. 1959. *Presented at the Meeting of the Optical Society of America, Columbus, Ohio, October 17-19, 1957.
19 : 30 : 51 171. Transmittance and Reflectance of Cesium Iodide in the Far Infrared Region. Earle K. Plyler and Nicolo Acquista, J. Opt. Soe. Amer. 48, No. 9, 668-669, Sept. 1958. 19 172. Infrared Spectra of Monolayers on Metal Mirrors. A double-beam infrared spectrophotometer has been modified so that spectra of films as thin as one or a few-monolayers in thickness on metal mirrors can be obtained. It is theoretically predicted and experimentally confirmed that, at the mirror surface, the electric intensity is predominantly perpendicular to the surface. Vibrational modes for which the matrix element of dipole moment is parallel to the surface appear abnormally weak in the spectra. The spectra, therefore, provide information about the orientation as well as the composition of sample films. Spectra of Blodgett films of metal stearates show differences in band positions and band intensities between films one molecular layer in thickness and thicker films. The shifts in band positions arc attributed to interactions between carboxylate ions in films thicker than a molecular layer and the absence of such interactions in the first layer. The intensity differences are not explained. (Author) S. A. Francis and A. H. Ellison, J. Opt. Soc. Amer. 49, No. 2, 131-138, Feb. 1959. 19 : 30 : 51 173. Luminescent Phases in Willemite Films. Red-, yellow-, and green-luminescent films have been formed by evaporation of powdered Zn2SiO4 (Mn). The yellow-emitting form was formed by firing the evaporated film plus additive in air at relatively low temperatures (750 °C). The red form was produced on Vycor substrates at higher temperatures (1100 °C). Infrared reflexion studies and x-ray diffraction analyses of these films indicate that the red-emitting form is SiO2(Mn) and that the yellow form is amorphous Zn~SiO4(Mn). The luminescence of both of these phosphors is probably due to interstitial manganese ions. The strong chemical reaction between the luminescent film and the glass substrate is brought out. (Author) Charles Feldman and Margaret O'Hara, J. Opt. Soe. Amer. 48, No. 11, 816-820, Nov. 1958. 19:30 174. Stokes' Equations and Their Application to the Refractivity of Thin Films. A solution to the problem of determining the refractivity of n identical planar arrays from the properties of a single array is obtained by first extending Stokes' equations to a form appropriate to a microscopic situation and then appropriately modifying Crook's results for thin films. The results of such development are found to be in agreement with data taken at microwave frequencies. (Author) A. F. Wickersham, Jr., J. Opt. Soc. Amer. 48, No. 12, 958-964, Dec. 1958. 19 : 29 : 30 175. Obtaining Low Orders of Interference in Measuring Film Thicknesses by Multiple Beam Interferometry. G. David Scott, J. Opt. Soe. Amer. 48, No. 11, 858, Nov. 1958. 19 : 29 : 51 176. Ultraviolet Transmission Properties of Conducting Coatings on Glass. D. W. Juenker and E. W. Parsons, 3". Opt. Soc. Amer. 48, No. 11, 857, Nov. 1958. 19 : 51 177. Pressure Modulation of Infrared Absorption. I. Entire Vibration-Rotation Bands. The effects of pressure modulation on the total absorption SA (v)dv of rotation-vibration bands of carbon monoxide,
Abstracts 167-177
process and the bimolecular recombination process. This equilibrium condition permits predictions of the dependence of the emission intensity, the efficiency, and other properties on several parameters such as the voltage, the temperature, and the concentrations of electron traps and activator centers. These predictions are compared with experimental results. (Author) Willi Lehmann, J. Opt. Soe. Amer. 48, No. 9, 647-653, Sept. 1958. 19 : 30 : 51 167. Reflexion Coefficient of Optically Inhomogeneous Layers. The reflexion coefficient is calculated for radiation incident normally on a non-absorbing, optically inhomogeneous, plane parallel layer bounded on either side by non-absorbing semiinfinite media. The theory is applied to determine the reflectance of a layer in which the index of refraction varies nearly linearly with the thickness. (Author) Joseph F. Hall, Jr., J. Opt. Soc. Amer. 48, No. 9, 654-657, Sept. 1958. 19:30 168. Optical Transmission of Evaporated IN, SN, and BI Films in the Vacuum Ultraviolet. W. C. Walker, O. P. Rustgi and G. L. Weissler, J. Opt. Soc. Amer. 48, No. 12, 1017, Dec. 1958. 19 : 30 169. Optical Constants of Evaporated Se Films by Successive Approximations. Experimental values of the refractive index ~ and the absorption constant k in the wavelength range 0.24 to 2.5 microns are reported for evaporated films of Se. Methods of successive approximation were used to obtain an average precision of ± 0.003 in the non-absorbing region and ~ 0.005 in the absorbing region. Electron microscope and electron diffraction techniques indicate that the Se films were amorphous and non-porous. (Author) W. E. Koehler, F. K. Odencrantz and W. C. White, J. Opt. Soc. Amer. 49, No. 2, 109-115, Feb. 1959. 19:30 170. Optical Properties of Various Evaporated Rare Earth Oxides and Fluorides.* To furnish a greater choice of film materials for application in optical multilayer coatings, the optical properties of evaporated rare earth compounds such as Y203, La6Oll, Pr203, Nd2Oa, Sm~Oa, LaF3, NdF3, and CF3 were studied in the wavelength region from 0.22 t~ to 2 tz. The materials were evaporated from tungsten boats and condensed on glass and fused quartz substrates at various temperatures. The optical constants n and k were determined mainly from reflectance, transmittance, and true thickness measurements. The following oxides were found to be useful because of their low absorption in the visible : La203 with n ranging from 1.85 to 1.95 with increasing thickness, Pr6011 with n ranging from 1.92 to 2.05, also with increasing thickness and Nd2Oa with n = 2.05 for films of sufficiently low absorption. LaF3 (n = 1.60) and NdFz (n = 1.61) showed no appreciable absorption in the whole wavelength region studied ; CeF3 (n = 1.63), however, exhibited two weak absorption bands at 0.234 and 0.248 t~. All n values are given at a wavelength of 0.5 tL and for unbaked films deposited at 300°C substrate temperature. The oxides condensed as almost amorphous films, whereas the fluorides developed fairly large grains as indicated by their sharp electron diffraction rings. All films were hard and showed excellent chemical and mechanical durability. (Author) G. Hass, J. B. Ramsey and R. Thun, J. Opt. Soc. Amer. 49, No. 2, 116--120, Feb. 1959. *Presented at the Meeting of the Optical Society of America, Columbus, Ohio, October 17-19, 1957.
19 : 30 : 51 171. Transmittance and Reflectance of Cesium Iodide in the Far Infrared Region. Earle K. Plyler and Nicolo Acquista, J. Opt. Soe. Amer. 48, No. 9, 668-669, Sept. 1958. 19 172. Infrared Spectra of Monolayers on Metal Mirrors. A double-beam infrared spectrophotometer has been modified so that spectra of films as thin as one or a few-monolayers in thickness on metal mirrors can be obtained. It is theoretically predicted and experimentally confirmed that, at the mirror surface, the electric intensity is predominantly perpendicular to the surface. Vibrational modes for which the matrix element of dipole moment is parallel to the surface appear abnormally weak in the spectra. The spectra, therefore, provide information about the orientation as well as the composition of sample films. Spectra of Blodgett films of metal stearates show differences in band positions and band intensities between films one molecular layer in thickness and thicker films. The shifts in band positions arc attributed to interactions between carboxylate ions in films thicker than a molecular layer and the absence of such interactions in the first layer. The intensity differences are not explained. (Author) S. A. Francis and A. H. Ellison, J. Opt. Soc. Amer. 49, No. 2, 131-138, Feb. 1959. 19 : 30 : 51 173. Luminescent Phases in Willemite Films. Red-, yellow-, and green-luminescent films have been formed by evaporation of powdered Zn2SiO4 (Mn). The yellow-emitting form was formed by firing the evaporated film plus additive in air at relatively low temperatures (750 °C). The red form was produced on Vycor substrates at higher temperatures (1100 °C). Infrared reflexion studies and x-ray diffraction analyses of these films indicate that the red-emitting form is SiO2(Mn) and that the yellow form is amorphous Zn~SiO4(Mn). The luminescence of both of these phosphors is probably due to interstitial manganese ions. The strong chemical reaction between the luminescent film and the glass substrate is brought out. (Author) Charles Feldman and Margaret O'Hara, J. Opt. Soe. Amer. 48, No. 11, 816-820, Nov. 1958. 19:30 174. Stokes' Equations and Their Application to the Refractivity of Thin Films. A solution to the problem of determining the refractivity of n identical planar arrays from the properties of a single array is obtained by first extending Stokes' equations to a form appropriate to a microscopic situation and then appropriately modifying Crook's results for thin films. The results of such development are found to be in agreement with data taken at microwave frequencies. (Author) A. F. Wickersham, Jr., J. Opt. Soc. Amer. 48, No. 12, 958-964, Dec. 1958. 19 : 29 : 30 175. Obtaining Low Orders of Interference in Measuring Film Thicknesses by Multiple Beam Interferometry. G. David Scott, J. Opt. Soe. Amer. 48, No. 11, 858, Nov. 1958. 19 : 29 : 51 176. Ultraviolet Transmission Properties of Conducting Coatings on Glass. D. W. Juenker and E. W. Parsons, 3". Opt. Soc. Amer. 48, No. 11, 857, Nov. 1958. 19 : 51 177. Pressure Modulation of Infrared Absorption. I. Entire Vibration-Rotation Bands. The effects of pressure modulation on the total absorption SA (v)dv of rotation-vibration bands of carbon monoxide,