A dual directional, wavelength demultiplexer including an optical fiber mounted and adhered to a curved surface having a clad single-fiber core, a planar surface extending partially into and along the fiber through the cladding, a prism mounted on the surface having two reflective surfaces positioned to receive multiple signals from the fiber travelling in opposite directions, optical gratings positioned at the reflective surfaces effective to diffract and demultiplex the signals, and photodiode...

The demultiplexer comprises a diffraction space defined by a reception surface coupled to a grating. In order to obtain output waves of flattened spectral response, the input waveguide and the reception surface are dimensioned so that the input wave diffracts over said surface and presents a plurality of secondary lobes. The demultiplexer is particularly applicable to optical communications systems with wavelength multiplexing.

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 converter for binary optical signals includes an interferometer structure (110) for generating an output signal by modulating a received local signal (LS) according to the modulation of a fUrther received first input signal (IS 1). When such interferometer structures (110) are operated in a standard mode it is known in the art to control the power of the input signal such that the extinction ratio of the output signal is kept minimal. The invention also controls the power of the inp...

The present invention can accurately detect a wavelength of a light to be detected, which is output from a source of light to be detected, without an error even if there is a change in the characteristic of a spectroscope due to an individual difference among the spectroscopes or a change in the measuring environment. The device according to the invention emits at least two reference lights (Ln, La) having different wavelengths (.lambda.n, .lambda.a) as the reference lights by reference light so...

A first polarizer separates an input light of the wavelength .lambda.2 into an X polarized wave and a Y polarized wave normal to each other. The input light of wavelength .lambda.2 is a linearly polarized wave. The X polarized wave is input to the second polarizer after passing through a semiconductor optical amplifier. The Y polarized wave is led by a reflecting device to the second polarizer. The refractive index of a waveguide of the semiconductor amplifier changes depending on the intensity ...

To obtain a laser beam the wavelength of 200 nm or less the repetition frequency of which is high, to reduce damage applied to mineral material such as synthetic fused silica, to extend the life of a stepper and others, to extend the life of laser parts without using toxic gas, to enhance the throughput of a stepper and others by enabling the compatibility of a high repetition frequency with the stability of a pulse, to realize an ultraviolet radiation source the whole of which is composed of a ...

A wavelength converter which has simple configuration and can be easily controlled and operated with stability, and used for a long-distance mass optical communication, comprises a waveguide for causing a change of a nonlinear refractive index. The converter includes a delay interference circuit having two optical paths and of different optical path lengths. A CW light source is input into the waveguide. A coherent length determined by a spectral line width of CW light output from the CW light s...

A wavelength router has first ports each receiving or providing a first multiwavelength optical signal having wavelengths, and second ports each providing or receiving second multiwavelength optical signals having multiplexed wavelengths. The number of multiplexed wavelengths of the second multiwavelength optical signal is smaller than the number of wavelengths of the first multiwavelength optical signal. The first multiwavelength optical signal is demultiplexed into the second multiwavelength o...

Scanning based wavelength measurement systems which are suitable for both localised and distributed WDM, High Density WDM, and coherent systems are based around the use of a fixed cavity Fabry-Perot Etalon which when the output of a tuneable laser is passed through it produces a number of reference equispaced transmission maxima. These maxima are used in a Scanning Heterodyne or Scanning Filter based Spectrometer for detection of the wavelength position of the transmitter.