This invention discloses an optical interleaver that includes a first collimating lens for collimating an input optical signal into collimated beams and a second collimating lens for focusing the collimated parallel beams into an output optical fiber. The interleaver further includes a phase delay difference generating means for generating a phase-delay difference between portions of the collimated parallel beams for generating an interference in the second collimating lens for selectively enhan...

A wavelength converter implements high speed, high efficiency, low noise wavelength conversion without performing high voltage poling of a crystal, and enables switching and modulation of converted light in response to an electric field. A KLTN crystal, includes a deposited-gold electrode within its incidence plane, and is connected to a DC power supply via a copper wire. The crystal material is composed of KTa.sub.1-x Nb.sub.x O.sub.3 and/or K.sub.1-y Li.sub.y Ta.sub.1-x Nb.sub.x O.sub.3. A pol...

A wavelength demultiplexer is provided whose overall length in a first propagation direction is short, whose production efficiency is high, and whose emission loss is smaller than that of conventional configurations. At the first end face V1, the first boundary line F1 is closer to the second edge H2 than the first edge H1 by the distance "b" (b>0). At the first end face V1, the second boundary line F2 is closer to the first edge H1 than the second edge H2 by the distance "b". At the third en...

The present invention seeks to increase the number of wavelengths capable of being handled while reducing the sub peak and beat noise. A wave router acording to the invention has three acoustooptical filter elements; two wavelength division multiplicity reduction elements; and two wavelength division multiplexers. The wavelength division multiplicity reduction elements have three output ports and one input port, and the wavelength division multiplexing optical signal input to this input port is ...

A wavelength converter is provided. The wavelength converter includes a substrate; first and second semiconductor optical amplifiers (SOAs) provided in parallel on the substrate, each of the SOAs including a first portion which passes light at one end, and a second portion which passes light at the opposite end; a first waveguide connected to the second portions of the first and second SOAs; a second waveguide connected to the first portion of the first SOA; and a third waveguide connected to th...

A wavelength router that selectively directs spectral bands between an input port and a set of output ports. The router includes a free-space optical train disposed between the input ports and said output ports, and a routing mechanism. The free-space optical train can include air-spaced elements or can be of generally monolithic construction. The optical train includes a dispersive element such as a diffraction grating, and is configured so that the light from the input port encounters the disp...

A wavelength router that selectively directs spectral bands between an input port and a set of output ports. The router includes a free-space optical train disposed between the input ports and said output ports, and a routing mechanism. The free-space optical train can include air-spaced elements or can be of generally monolithic construction. The optical train includes a dispersive element such as a diffraction grating, and is configured so that the light from the input port encounters the disp...

An object of the invention is to provide a wavelength locker which has a wider locking range than that of the wavelength locker in the prior art and which can cope with a plurality of wavelengths. The aforementioned objects are achieved by a wavelength locker, which comprises a periodic filter, a detecting part for detecting the intensity of a laser beam through the periodic filter, and a controlling part for controlling the wavelength of the laser beam to a desired wavelength in accordance with...

A wavelength converter has a phase modulated periodically modulated structure, where a nonlinear optical coefficient is periodically modulated at a fundamental period .LAMBDA..sub.0 and the phase of the modulation varies nearly continuously, and the phase variation of the modulation unit structure is repeated at a period .LAMBDA..sub.ph (>.LAMBDA..sub.0). A conversion efficiency is made maximum when a phase mismatch amount .DELTA..beta. equals 2.pi./.LAMBDA..sub.0.+-.2.pi.i/.LAMBDA..sub.ph (i...

A wavelength selective demultiplexer tuner having an optically transmissive body for receiving an input signal containing a plurality of different wavelengths and transmitting the signal therethrough. An electro-optic block of material is secured to the body of the tuner and a reflective grating or mirror is secured to the electro-optic block of material for redirecting through the body the input signal as a plurality of signals, each containing a different one of the wavelengths. By appropriate...