Optical switch

About: Optical switch is a research topic. Over the lifetime, 28538 publications have been published within this topic receiving 351176 citations.

Reconfigurable multilevel phase holograms for optical switches

Abstract: A way of dynamically encoding polarization-insensitive multilevel phase holograms using nematic liquid crystals is presented. The method, using a quarter wave plate and a mirror, allows the optical efficiency of a free space single-mode fiber-to-fiber switch to be greatly enhanced. The validity of the approach has been verified experimentally by observing the power diffracted in the /spl plusmn/1 orders of a nematic liquid crystal grating as a function of input polarization and applied voltage.

Vertical to surface transmission electrophotonic device with selectable output light channels

Abstract: A photoeletronic bistable device with selectable light output channels has been fabricated for implementation in photonic switching and processing systems. The device is a variation of the vertical to surface transmission electrophotonic device. Output in the stimulated light emission mode was successfully obtained from different waveguide channels by external electronic switching. Output channels could be switched at a rate of 400 Mb/s. The potential versatility of this device has been experimentally confirmed in programmable or switchable optical interconnections.

Distributed lighting system with fiber optic controls

Abstract: A vehicle lighting system includes one or more central light sources, a plurality of optical loads including headlight lenses, an optical fiber network that extends from the light sources to illuminate the headlight lenses and other optical loads, and optical switches and oscillators that include respective input fibers illuminated from the light source and output fibers to respective optical loads, and operate by enabling and disabling optical connections between their input and output fibers. The headlight assemblies switch between high and low beams by moving their fibers vertically, and control beam diffusion by moving the fibers parallel to the lens axes, including an automatic diffusion adjustment for a headlight reflection from a vehicle in front. The switches include various mechanisms for moving the input and output fibers into and out of alignment with each other, including a shaped resilient sleeve, a hinge pivotally joining the fibers, an opaque shutter with a transmissive section movable between the fibers, and also a liquid-based switch that relies upon total internal reflection. A feedback mechanism for some of the switches dims the source lamp when the switch is OFF to conserve energy. The oscillators operate by normally urging an input fiber towards an OFF position, at which it actuates a mechanism that shifts it to an ON position at which the mechanism is deactivated. A failsafe system employs multiple light sources, with each source sharing its light output with the load for another source that has failed.

Bistability and all-optical switching in semiconductor ring lasers

Abstract: Semiconductor ring lasers display a variety of dynamical regimes originating from the nonlinear competition between the clockwise and counter-clockwise propagating modes. In particular, for large pumping the system has a bistable regime in which two stationary quasi-unidirectional counter-propagating modes coexist. Bistability is induced by cross-gain saturation of the two counter-propagating modes being stronger than the self-saturation and can be used for data storage when the semiconductor ring laser is addressed with an optical pulse. In this work we study the response time when an optical pulse is injected in order to make the system switch from one mode to the counter-propagating one. We also determine the optimal pulse energy to induce switching.