Showing papers on "Step-index profile published in 1969"

Refractive Index of Cuprous Chloride

Abstract: The refractive index of single-crystal CuCl at room temperature was measured in the wavelength range 0.42–1.2 μm using a V-block refractometer. The range of wavelengths was extended to 22 μm by measuring the wavelength dependence of interference fringes in thin polished plates. A dispersion equation was fitted to the data over a limited wavelength range.

Thermal Coefficient of Refractive Index of Optical Glasses

Abstract: The thermal coefficients of refractive index have been determined for 23 commercial glasses. The interferometric procedure consisted of determining both the change of optical path of each glass with a change of temperature at a given wavelength and set coefficient of linear thermal expansion of the glass for the same temperature range. A relationship for the dispersion of the thermal coefficient of the refractive index has been found. It has also been possible to relate the chemical composition of glass with the thermal coefficient of the refractive index.

Photoelectric converter including convergent lens with refractive index distribution

Abstract: Disclosed herein is a photoelectric converter including a convergent lens with a transparent member having a refractive index distribution, in a cross section perpendicular to a travelling axis of light, so as to substantially satisfy the equation: NR NO(1-AR2) WHEN A REFRACTIVE INDEX AT THE CENTER OF THE CROSS SECTION IS NO, A REFRACTIVE INDEX AT A DISTANCE R FROM THE CENTER IS NR AND A POSITIVE CONSTANT IS A.

A Special Method for Precise Refractive Index Measurement of Uniaxial Optical Media

Abstract: A method was developed for measuring the refractive index of optical glasses and uniaxial crystalline solids when established refractometric methods are not feasible. A synthetic ruby cuboid was contacted to a prism of known refractive index and a spectrometer was used to measure the angles describing the optical path through the ruby-glass combination. Ray tracing equations were derived to compute the refractive index accurate within 3 × 10−5. Index values for both polarizations of ruby are given at selected wavelengths from 0.4358 μm to 0.7065 μm.

Gradient refractive index light-conducting glass structure

Abstract: A light-conducting glass structure, the refractive index of which in each cross section perpendicular to the centre line or plane along which light is to advance of the structure decreases progressively from the centre line or plane toward the outer surface of the structure, and the rate of decreasing the refractive index is smaller at the vicinity of at least either end surface being transverse to the centre line or plane than that in the other part of the glass structure. The decrease of refractive index occurs by varying the concentration within the glass structure of at least two kinds of cations (They differ from each other in their contributions to increasing of refractive index.) constituting modifying oxides. The rate of decreasing refractive index at the vicinity of at least either end surface of the glass structure is made to carry out by such a manner that the cation within the glass structure (Which is either of at least two kinds of cations mentioned above and has higher contributions to the increase of refractive index than that of the other.) is substituted by another cation from an external cation source in a greater extent, or a stretching ratio of a part to be an end surface of the glass structure having a certain rate of decreasing refractive index is adjusted to be smaller.

Variation of refractive index of solutions with wavelength.

Abstract: Chaubal, Lodin and Korgaonkar (3) and Chaubal, Lodin and Pilny (4) have rightly stated that the development of two-wavelength methods of interference microscopy requires an accurate knowledge of the refractive indices of both the medium and the specimen at different wavelengths. In a recent note (3) they have attempted to derive formulae expressing the variation of the refractive index of protoplasm with wavelength. Their derivation is somewhat cumbersome and includes an assumed value of 100 m i for the optical path difference of a typical cell. Since the optical path difference (which is related to dry mass per unit area) is itself the product of concentration and thickness it rests on two independent variables. A simpler and more fundamental derivation can be obtained by considering the way in which the refractive index varies with concentration. According to the well known relationship (1, 2)

Optical cell for isochoric measurements of refractive index near the critical region

Abstract: An optical cell is described, suitable for measuring the temperature dependence of the refractive index n of a fluid at constant density near Tc. Based on the spectroscopic method of minimum deviation, the method determines n to ?0?012%.