Showing papers on "Guided wave testing published in 1979"

Integrated-optic spectrum analyzer(Invited Paper)

Abstract: This paper describes the integrated-optic implementation of a Bragg spectrum analyzer that employs the interaction between a coherent optical guided wave and a surface acoustic wave to determine the power spectral density of the input. The integrated-optic spectrum analyzer (IOSA) consists of an injection laser diode, a thin-film optical waveguide, waveguide lenses, a surface-acoustic-wave (SAW) transducer, and a linear detector array with CCD readout. Design principles are given for selecting component parameters such as optical beam width, detector cell size, lens aperture and focal length, and acoustic transducer design so as to obtain specific RF resolution, spurious level, and signal-to-noise ratio. Design parameters are presented for a 750-1250-MHz spectrum analyzer with a resolution of 4 MHz and a 40-dB dynamic range. Also described in the paper is the development of the state-of-the-art component technology for the spectrum analyzer.

Scattering of guided optical beams by surface acoustic waves in thin films

Abstract: A new approach to the problem of light scattering by surface acoustic waves in thin-film optical waveguides is presented. In this analysis electromagnetic fields are found to rigorously satisfy both the polarization driven wave equation and the electromagnetic boundary conditions at the frequencies of interest. A component of the solution field is found to evolve with propagation distance into a linearly growing guided wave mode that dominates the solutions under conditions that can be defined in terms of waveguide mode parameters. Analytical formulas for the growth coefficient are obtained for both the elasto–optic and corrugation scattering mechanisms for the geometries TEm → TEm, TEm → TMm, TMm → TMm and TMm → TEm The present results are found to be consistent with previous normal mode analyses of this phenomenon for the cases in which comparison is possible. Numerical calculations for thin films of As2S3 and Corning 7059 glass on fused silica substrates indicate that the elasto-optic effect does not always dominate the scattering cross section and that the corrugation mechanism must often be taken into account.

Sub)millimeter Guided-Wave E:~periments with Polyethylene Slab Waveguides

Abstract: The attenuation constants of a symmetric polyethylene slab waveguide are measured in the submillimeter-wave region at lambda/sub 0/= 337 mu m. In our experiments the fine metal grating is used as a coupler, instead of a usual prism coupler. Our coupler which is different from the conventional grating coupler fixed on a slab is easily movable along a slab without a fluctuation in the coupling efficiency, and the loss measurement is successfully performed for several kinds of slab thicknesses by using such couplers. As a result, the attenuation constant of about 1.3 dB/m is measured, in good reliability, for a slab of 10 mu m in thickness. Finally, to make clear the accuracy of our loss measurements, the transverse broadening of the field along the propagating direction of a slab is measured experimental!y, and it is concluded that there is little influence of the transverse broadening on the measured attenuation constants.

Guided Wave Optical Systems and Devices

Abstract: (1979). Guided Wave Optical Systems and Devices. Optica Acta: International Journal of Optics: Vol. 26, No. 12, pp. 1457-1457.

Mode coupling between slab‐type optical waveguides via dichroic absorption of M centers

Abstract: Guided wave coupling in slab‐type optical waveguides covered with an NaF crystal containing oriented M centers is analyzed with the complex propagation constant. In this treatment the complex coupling coefficient is also introduced. An additional experiment supports this analysis. This conception is useful in designing optical waveguide functional devices.

Submillimeter Guided-Wave Experiments with Polyethylene Slab Waveguides

Abstract: The attenuation constants of a symmetric polyethylene slab waveguide are measured in the submillimeter-wave region at lambda/sub 0/= 337 mu m. In our experiments the fine metal grating is used as a coupler, instead of a usual prism coupler. Our coupler which is different from the conventional grating coupler fixed on a slab is easily movable along a slab without a fluctuation in the coupling efficiency, and the loss measurement is successfully performed for several kinds of slab thicknesses by using such couplers. As a result, the attenuation constant of about 1.3 dB/m is measured, in good reliability, for a slab of 10 mu m in thickness. Finally, to make clear the accuracy of our loss measurements, the transverse broadening of the field along the propagating direction of a slab is measured experimental!y, and it is concluded that there is little influence of the transverse broadening on the measured attenuation constants.

New Edge Guided Wave on Ferrite Strip

Abstract: Electromagnetic wave propagation along ferrite strip whose cross section is square immensed in D.C. magnetic field is investigated experimentaly. The existence of the mode similar to edge guided mode in ferrite substrate microstrip line was discovered. This mode may be useful for nonreciprocal circuit in millimeter and optical integrated circuit.