Switches optical

Optical storage disks Optical storage media Optical switches Optical trapping Optical tweezers Optical wave guides... 

Achieved NotoI °pi>cal memory, photon-mode spatial light modulation, ulttafast optical parallel switching, optical enhancement of nonlinear optical properties, etc... 

The operation of proximity sensors can be based on a wide range of principles, including capacitance, induction, Hall and magnetic effects variable reluctance, linear variable differential transformer (LVDT), variable resistor mechanical and electromechanical limit switches optical, photoelectric, or fiber-optic sensors laser-based distance, dimension, or thickness sensors air gap sensors ultrasonic and displacement transducers. Their detection ranges vary from micrometers to meters, and their applications include the measurement of position, displacement, proximity, or operational limits in controlling moving components of valves and dampers. Either linear or angular position can be measured ... 

High quantum yield photochemical reactions of condensed-phase species may become useful for future optical applications such as molecular switches, optical limiters, and read-write data storage media. Toward these ends, much research has been conducted on novel nonlinear chemical-based materials such as conducting polymers and metal-organic species. Monitoring the early time-dependent processes of these photochemical reactions is key to understanding the fundamental mechanisms and rates that control the outcome of these reactions, and this could lead to improved speed and efficiencies of devices. 

Microfabricated devices capable of switching optical light beams, also termed MOEMS, have gained attention about a decade ago for applications like optical fiber switches, microscanners, or digital micromirror arrays. Particularly, the latter devices have found widespread application in video projection systems for office presentations, home cinema, and very recently, the replacement of classical projectors in movie theaters. Other applications, for example, for head-up displays on auto windscreens are in development. In all cases, arrays of small micromirrors are used for the modulation of light. 

In the Cu(DCNQI)2 radical-anion salt in the neighbourhood of the Peierls phase-transition temperature, it was found that the insulating state can be switched optically on a time scale of less than 20 ps into the conducting state (F. O. Karutz, H. C. Wolf et al, Phys. Rev. Lett. 81,140 (1998)). This optical switching process was termed a reversed Peierls transition . From the current transients, it was found that the switched volume must be at least 100 times larger than the directly photo-... 

Tajima K, S. Nakamura and Y. Ueno (2001) "Ultrafast all-optical signal processing with Symmetric Mach-Zehnder type all-optical switches" Optical and Quantum Electronics, Volume 33, Numbers 7-10 / July, 2001. 

Mr. Ghanshyam Singh. He has completed B.E from REG Sdchar (1997), M.Tech from MNIT Jaipur (2003) and is currently pursuing PhD. His areas of interest include Optical Communication, Optical Switches, Optical digital logics Interconnects. 

Papuchon, M. et al. 1975. Electrically switched optical directional coupler COBRA. Appl. Phys. Lett. 27 289-291. 

Polydiacetylenes are polymers showing a one-dimensional semiconducting behaviour. This one-dimensional structure causes exceptionally high third order non-linearities [100], also in off-resonant wavelength regions [101], with extremely short sub-picosecond switching times [102]. After this discovery it was believed that an optical amplifying switch (optical transistor) or even an optical computer was close at hand. 

Waveguide components are also applied in photonic devices. Based on polymers, these can be easily manufactured at low cost, with typical applications ranging from computer backplanes that combine electrical and optical cables, thermo-optical switches, optical splitters of multichannel high-density planar lightwave circuits to polyimide-based electro-optical (EO) modulators. 

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