Optical modulator

About: Optical modulator is a research topic. Over the lifetime, 14068 publications have been published within this topic receiving 196932 citations.

Spatial light modulator system

Abstract: A display projection apparatus comprising a light source, means for splitting light from the source into different color component beams, and a plurality of deformable mirror device spatial light modulators, characterised in that the light paths to said splitting means and modulators are provided as a single prism assembly to which said modulators are mounted.

Lossless optical modulation in a silicon waveguide using stimulated Raman scattering

Abstract: In this paper we describe a new modulation scheme using stimulated Raman scattering in conjunction with a reverse biased p-i-n diode embedded in a silicon waveguide. We show optical modulation of a weak probe beam by modulating the reverse bias voltage of the silicon waveguide excited by a strong pump beam. The probe beam modulation is due to the two-photon absorption-induced carrier density modulation in the waveguide. By tuning the probe wavelength to the Stokes wavelength, we demonstrate for the first time a lossless optical modulator in silicon with modulation speeds up to 80-MHz.

Device physics of the soft‐mode electro‐optic effect

Abstract: The soft‐mode ferroelectric liquid‐crystal (SMFLC) effects utilize the electroclinic response of chiral orthogonal smectic phases (A*,B*,E*) in bookshelf geometry. The SMFLC cell may be considered a retardation plate with a field controllable optic axis, with a submicrosecond response time, and a wide continuous dynamic range. A great variety of electro‐optic components and devices can be constructed based on the SMFLC effect, many of them adding novel possibilities and challenges for optical design. We discuss in the present paper different combinations of SMFLC cells with retarders and polarizers, giving optical components capable of light and color modulation. Particularly, multiple electroclinic cells in a special constellation have the potentiality to give nearly achromatic full‐modulation light valves, as well as electrically controlled high‐speed color filters, which can be used for simple and compact TV cameras. Reflective single‐cell electroclinic devices are suitable for integration with semiconductors to give high‐speed spatial light modulators and general optical processing components with high contrast and full grey‐scale capability.

Optical amplifier and optical communication system provided with the optical amplifier

Abstract: An optical communication system transmits information with a pumping light beam acting as the carrier, and with a signal light beam. This optical communication system includes an optical fiber amplifier adapted to amplify the signal light beam by having the signal light beam and the pumping light beam propagate through a rare-earth-doped fiber doped with a rare-earth element. A modulating circuit modulates the pumping light beam with a high-frequency modulating signal having a period shorter than the life span of fluorescence resulting from an excited state. When the signal light beam and the pumping light beam are propagated in the same direction through the rare-earth-doped fiber, the transmission of information with the pumping light beam acting as the carrier, can provide transmission of a supervisory signal for an optical repeater. When the signal light beam and the pumping light beam are propagated in opposite directions through the rare-earth-doped fiber, a two-way transmission can be achieved by the transmission of information with the signal light beam and the transmission of information with the pumping light beam.

33 ps optical switching of symmetric self‐electro‐optic effect devices

Abstract: We describe a new method of operation of symmetric self‐electro‐optic effect devices (S‐SEEDs) using excitation pulses shorter than the diode sweep out times. We shall call this dynamic SEED switching. Previous SEEDs are optically bistable logic devices which use the unique properties of multiple quantum well structures placed in the intrinsic i regions of two p‐i‐n diodes reverse biased in series. Conventional operation of S‐SEEDs is at the exciton wavelength where absorption decreases with increasing electric field. Utilizing the dynamic properties of the S‐SEED we demonstrate that switching is possible at any wavelength where there is a nonlinear response showing a threshold. The major advantages of dynamic over conventional operation, is that it can be faster while requiring less optical energy, is automatically reset each cycle, and is less susceptible to saturation.