Abstract: The organic EL emission device includes an organic light emission layer for EL emission sandwiched between first and second electrode layers, at least one of which is transparent. At least the first electrode layer includes a plurality of electrodes arranged with spatial periodicity. The plurality of electrodes included in the first electrode layer together with adjacent regions in the second electrode layer including one or more electrodes form a plurality of electrode pair regions arranged with spatial periodicity. The method of driving the organic EL emission device is characterized in that electric fields having either different strengths or directions are applied with variation in a time-dependent manner to electrode pair regions adjacent to each other among the plurality of electrode pair regions.

Abstract: An optical memory semiconductor laser apparatus incorporating a recording semiconductor laser device for an optical memory and a replaying semiconductor laser device for an optical memory therein into a single body, wherein the oscillation threshold current of replaying semiconductor laser device is smaller than that of recording semiconductor laser device.

Abstract: A higher harmonic wave generator, comprising: (1) a first optical waveguide made of a nonlinear optical material, having a structure which can guide the incident fundamental wave; and (2) a second optical waveguide made of nonlinear optical material, connected to the first optical wave guide optically, having a structure which can guide a higher harmonic wave of the fundamental wave; wherein the effective refractive index of the first optical waveguide is made to be equal to the effective refractive index of the second optical waveguide.

Abstract: A semiconductor laser apparatus includes a groove of a specified length that is formed by etching an end portion of a semiconductor laser element, and a higher harmonic generating device having a waveguide of approximately the same cross-sectional dimensions as the dimensions of the resonator that is mounted in the semiconductor laser element. The higher harmonic generating device is secured by being fused in the groove with the optical axis of the waveguide coinciding with the optical axis of the resonator.

Abstract: An integrated optical disc pickup comprising an optical waveguide in the form of a insulation layer provided on the surface of a substrate, a semiconductor laser disposed outside the waveguide, a beam splitter of the transmission type and a Luneburg lens provided on the path of propagation of a laser beam from the semiconductor laser through the waveguide and arranged in the order mentioned in a direction away from the laser, a transmission grating provided on the path through the waveguide to be followed by the laser beam upon having its direction changed by the beam splitter after emanating from the laser, passing through the beam splitter and the Luneburg lens, being reflected from an optical disc disposed outside the waveguide and passing through the Luneburg lens, and first and second photodetectors disposed on the paths of propagation through the waveguide of two portions of the laser beam divided by the diffraction grating.

Abstract: A semiconductor harmonic generating device comprising a nonlinear medium and a waveguide which is provided in the upper face of the nonlinear medium. A higher harmonic laser light from a fundamental wave laser light which passes through the waveguide, wherein the waveguide has refractive index dispersion means for counterbalancing the refractive index difference caused by wavelength dispersion, occurring in the nonlinear medium, between the fundamental wave laser light and the higher harmonic laser light.