摘要:
A chromatic dispersion device according to the invention comprises an input/output waveguide, a plurality of first ring waveguides and a second ring waveguide. The plurality of first ring waveguides optically couple with the input/output waveguide through directional coupling and are disposed along an optical axis direction of the input/output waveguide, each ring waveguide having a predetermined FSR (free spectral range) and group delay characteristics with a peak value of the same polarity. The second ring waveguide optically couples with the input/output waveguide through directional coupling, the second ring waveguide having the predetermined FSR and group delay characteristics with a peak value of a polarity different from those of the first ring waveguides.
摘要:
An object of this invention is to improve coupling efficiency of a silica optical waveguide having a high relative refractive index difference and a single mode optical fiber. A silica optical waveguide (10) consists of a single mode optical waveguide, and its core (12) is originally a rectangle. A width of the core (12) of the silica optical waveguide (10) is tapered at a predetermined length part (16) connecting to an optical fiber (20). A thickness of the core (12) in the tapered part (16) is constant.
摘要:
A chromatic dispersion device according to the invention comprises an input/output waveguide, a plurality of first ring waveguides and a second ring waveguide. The plurality of first ring waveguides optically couple with the input/output waveguide through directional coupling and are disposed along an optical axis direction of the input/output waveguide, each ring waveguide having a predetermined FSR (free spectral range) and group delay characteristics with a peak value of the same polarity. The second ring waveguide optically couples with the input/output waveguide through directional coupling, the second ring waveguide having the predetermined FSR and group delay characteristics with a peak value of a polarity different from those of the first ring waveguides.
摘要:
An optical circulator outputs an optical signal entered through its port A from its port B. A fiber collimator makes the optical signal spread out from the port B of the optical circulator into a collimated beam and applies it to a beam splitter. The beam splitter is disposed at an angle of 45° to the optical axis. Around of the beam splitter, total reflection mirrors are disposed in three directions per angle of 90° except for the direction in which the fiber collimator is disposed. The distance between the total reflection mirrors and the beam splitter is adjustable.
摘要:
An optical gate according to the invention comprises a polarization divider to divide an optical signal into two orthogonal polarization components and to output them as a first polarization component which precedes in the time base and a second polarization component which follows the first one in the time base; a semiconductor optical amplifier to modulate the phase of the second polarization component output from the polarization divider according to a control light; an assist light supplier to supply to the semiconductor optical amplifier an assist light to help the recovery of the refractive index variation of the semiconductor optical amplifier caused by the control light; a polarization combiner to combine the first and second polarization components of the optical signal transmitting on the semiconductor optical amplifier so as to adjust them in the same time location; and a polarization extractor to extract a predetermined polarization direction component from the output from the polarization combiner.
摘要:
An optical signal processor is disclosed comprising a first optical path having a first electroabsorption optical modulator to be applied with a constant voltage and to absorb light of a signal wavelength, a second optical path having a fixed phase relation with the first optical path relative to a probe wavelength, a probe light introducer for dividing probe light of the probe wavelength into two portions and feeding them respectively into the first and second optical paths, an original signal light introducer for introducing original signal light of the signal wavelength into the first electroabsorption optical modulator, and a combiner for combining both light of the probe wavelength passed through the first and second paths.
摘要:
A first semiconductor optical amplifier is disposed on a first arm of a Mach-Zehnder interferometer and a second semiconductor optical amplifier is disposed on a second arm. An optical splitter splits a probe light into two portions and applies one portion to the first arm and the other to the second arm. A first optical coupler combines the probe lights output from the first and second arms. A second optical splitter splits a data light into two portions. A second optical coupler applies one output from the second optical splitter to the first arm in the backward direction. A third optical coupler applies the other output from the second optical splitter to the second arm in the forward direction.
摘要:
A transmission band filter (110) having a series of elements (111, 113, 115) each composed of a film bulk acoustic resonator and grounded shunt elements (112, 114) each composed of a film bulk acoustic resonator is connected between a transmission port (102) and an antenna port (106). A reception band filter (130) having a series of elements (131, 133, 135) each composed of a film bulk acoustic resonator and grounded shunt elements (132, 134, 136) each composed of a film bulk acoustic resonator is connected between a reception port (104) and the antenna port (106). A film bulk acoustic resonator (150) for adjustment is connected between the antenna port (106) and the ground. The resonance frequency of the adjusting film bulk acoustic resonator (150) lies between the upper limit frequency of the transmission frequency pass band of the transmission band filter (110) and the lower limit frequency of the reception frequency pass band of the reception band filter (130). Therefore a duplexer such that it can be a monolithic element, the power handling capability is good, the size is small, and the cost is low is provided.
摘要:
An alarm timepiece is disclosed which is capable of setting a plurality of alarm settings and selecting which of a plurality of messages should be outputted in association with a respective alarm setting. Selected messages are output by a speech synthesis technique, and an exchangeable ROM cassette is provided for containing speech-synthesizing data characteristic of the content of the messages.