Optical Switch For The Design Of Crossbar Network

In recent years, with the rapid development of optical communication, opticalcommunication of information processing capacity is increased in exponential type, how toestablish the high speed, high bandwidth and large capacity has become the focus of currentresearch. Optical networks can be on the beam transmission line, integrated optical circuitsare one of the key elements of mutual conversion, logic operation is the light switch, so thekey devices of optical network optical switch has higher requirements. Require light switchdevice on the technical indicators to improve switch response speed, reduce the insert loss andprolong the working life, more in volume caused by the network components, miniaturization,as far as possible in order to make the optical network requires the optical switch device hashigher level of integration. At present, in order to better structure of optical network, thedevelopment of free space transmission integrated optical switch is very important.Therefore,the design of a light switch type integrated free space. The main results were as follows:1.Design of the free space of a single piece of lithium niobate integrated2×2opticalswitch. The optical switch using crystal birefringence effect realized beam and beam, twobeams of orthogonal linear polarized light through a double refraction and total internaldouble reflection after synthesis of a beam, transmission and along the optical axis direction,and then after a total internal double reflection and refraction divided into two beams.Toachieve the modulation of the polarization state of light beam by using transverse crystalelectro-optic effect, when the half wave voltage in the x1axis direction, the beam polarizationrotation90°, switch to direct state, without voltage, beam polarization state unchanged, switchto cross state. Taking into account the crystals of o light and e light total reflection criticalangle is different, the two linear polarized light from different interface injection (exit) crystal,so that the two light beams with larger separation angle, more suitable for application inCrossbar optical network. The integration of the2×2optical switch has the advantages ofsimple structure, low energy consumption, low crosstalk, low half-wave voltage, switchingresponse time is short, strong anti-interference, easy installation cascade etc..2.With lithium niobate crystal produced a2×2electro-optical switch, and its performancewas tested. The maximum insertion loss of the switch is9dB, which is mainly due to theincident surface and the exit surface reflection caused by Finel. Crosstalk maximum-15dB,and this is mainly due to the driving voltage deviation, half wave voltage beam caused by notstrictly along the optical axis transmission.