Abstract: The present invention pertains to a polarization independent tunable acousto-optical filter and the corresponding method. The filter diffracts an input light beam into a first input light beam unaffected by acoustic waves and a second input light beam affected by acoustic waves. A polarization beam displacer/combiner is employed to separate the input light beam into two orthogonal beams. Several polarized rotators are used to rotate the polarization of light by 90 degrees. An acousto-optical device makes the polarization of light with a particular wavelength rotate by 90 degrees. The two beams are then properly combined to form orthogonal beams. The filtering method has nothing to do with the polarization of the incident light. The filter has such advantages as a high extinction ratio, a small volume and a lower cost.

Abstract: The present invention pertains to a polarization independent tunable acousto-optical filter and the corresponding method. The filter diffracts an input light beam into a first input light beam unaffected by acoustic waves and a second input light beam affected by acoustic waves. A polarization beam displacer/combiner is employed to separate the input light beam into two orthogonal beams. Several polarized rotators are used to rotate the polarization of light by 90 degrees. An acousto-optical device makes the polarization of light with a particular wavelength rotate by 90 degrees. The two beams are then properly combined to form orthogonal beams. The filtering method has nothing to do with the polarization of the incident light. The filter has such advantages as a high extinction ratio, a small volume and a lower cost.

Abstract: A thin film optical scanner using phonon echoes. A piezoelectric (an insulator or a semiconductor) crystal has deposited thereon a photoconductor. An acoustic transducer propagates a broad strain wave pulse guided in or on the crystal. A relatively shorter electric field pulse is coupled to the piezoelectric crystal through the photoconductor which has an optical signal focused thereon. The interaction of electric field and strain wave produce a backward travelling acoustic wave which is modulated by the optical signal.

Abstract: A scanning apparatus for converting an optical line image to a serial electrical analog signal by launching an acoustic wave in a plurality of ridged waveguides each of a different length. In one embodiment the launching transducer includes an electro-optical layer which modulates the acoustic wave as a function of the incident light intensity. In a second embodiment the acoustic wave is launched in each waveguide with the same amplitude but interacts with an acousto-optical overlay on the waveguide to amplitude modulate the intensity of the propagating acoustic wave. The thus generated and modulated acoustic waves are converted to electrical signals either by reflection back to the launching transducer or by individual transducers on each channel. The differing lengths converts the parallel image to a series electrical signal.

Abstract: An optical assembly structure wherein miniature optical components such as lasers, modulators, lenses, thin-film and fiber-optic waveguides, and photodetectors are critically aligned and supported for coactive operation by means of two or more wafers which are formed with complementary grooves and mortises to support the loose optical components such as lenses and fiber-optic waveguides and to receive alignment rails to insure the relativity of the wafers, which also have formed integral therewith optical elements such as waveguides, modulators, and lasers, to produce an integrated optical assembly somewhat in the manner of an "optical bench," wherein the bench structure also provides an active optical element.

Abstract: An injection laser, which is chemically etched to provide mirror-like surfaces, also is provided with a chirped diffraction grating. The latter grating, which is etched in the injection laser, combines with the chemically etched sides to provide laser emission in a direction substantially parallel to the current flowing through the laser. As an alternative to the chirped diffraction grating, waveguides are included in the resulting folded cavity laser. Either of the above structures relaxes the fabrication tolerance in the inclined surfaces etched in the laser relative to known folded cavity lasing structures.

Abstract: An optical structure for the bidirectional coupling of light between each of a multiplicity of optical fibers and corresponding individual thin-film waveguides to achieve a leaky wave coupling from one guided mode structure to a second guided mode structure. The structure is particularly suited for fabrication by planar deposition and etching techniques and features the precise axial alignment of the optical elements by inserting the fibers in etched V-grooves in the substrate upon which are deposited the waveguides.