Optical processing device with wavelength stabilization and optical switch using such a device

Claim 2

An optical processing device as claimed in claim 1 characterized in that said optical processing means comprises a filter device (13) having a variable transmission wavelength, said filter device being controlled by said control unit and selectively passing the optical signal of the first wavelength that is specified by the control unit, a photodetector (14) supplied with the optical signal that has passed through the filter device with the first wavelength for detecting the same, said photodetector producing an output electric signal in response to the optical signal, and an optical modulation unit (15) supplied with said control optical beam for modulating the same in response to the output electric signal of the photodetector.

Claim 3

An optical processing device as claimed in claim 1 characterized in that said second wavelength is set identical with the reference wavelength.

Claim 4

An optical processing device as claimed in claim 2 characterized in that said optical processing means (11) further comprises wavelength conversion means (17) for converting the wavelength of the optical beam produced by the optical modulation unit.

Claim 5

An optical path selector system for switching a path of an optical signal, characterized by: a plurality of electro-optic conversion devices (23₁ - 23 n ) respectively supplied with electric signals for converting the same to corresponding optical signals with respective wavelengths that are different from each other; optical multiplexing means (24) supplied with the output optical signals of the electro-optic conversion devices for mixing the same to form a wavelength-multiplexed optical signal, said wavelength-multiplexed optical signal containing said optical signals with the respective wavelengths that are different from each other as component optical signals, said optical mixing means having a plurality of output ports and distributing the wavelength-multiplexed optical signal to said plurality of output ports; a plurality of optical processing devices (21₁ - 21 n ) connected to each of said plurality of output ports for receiving said wavelength-multiplexed optical signal, each of said plurality of optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal of a predetermined wavelength from said wavelength-multiplexed optical signal and outputting the selected optical signal with a wavelength determined by said reference wavelength; and a reference optical beam generator (22) for producing said reference optical beam and supplying the same to said plurality of optical processing devices with respective wavelengths.

Claim 6

An optical path selector system for switching a path of an optical signal, characterized by: a plurality of electro-optic conversion devices (23₁ - 21 n ) respectively supplied with electric signals for converting the same to corresponding optical signals with respective wavelengths that are different from each other, said plurality of electro-optic conversion devices being divided into a plurality of groups each including a plurality of electro-optic conversion devices; a plurality of optical processing devices (21₁ - 21 n ) connected to each of said plurality of electro-optic conversion devices for receiving said wavelength-multiplexed optical signal, said optical processing devices being grouped into a plurality of groups corresponding to the plurality of groups of the electro-optic conversion devices, each of said plurality of optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal of a predetermined wavelength from said wavelength-multiplexed optical signal and outputting the selected optical signal with a wavelength determined by said reference wavelength; and a reference optical beam generator (22) for producing said reference optical beam and supplying the same to said plurality of optical processing devices with respective wavelengths, said reference optical beam generator supplying the reference optical beams to said plurality of optical processing devices with the reference wavelengths that are different from each other in each group of said optical processing devices.

Claim 7

An optical matrix switch for switching a wavelength-multiplexed optical beam carrying thereon a number of optical signals of different wavelengths, characterized by: a plurality of first optical transmission lines (33) each supplied with an input wavelength-multiplexed optical signal and transmitting the same, said input wavelength-multiplexed optical signal containing therein a plurality of input optical signals with respective wavelengths (λ₁′ - λ n ′) that are different from each other; a plurality of second optical transmission lines (34) each supplied with an output wavelength-multiplexed optical signal and transmitting the same, said output wavelength-multiplexed optical signal containing therein a plurality of output optical signals with respective wavelengths that are different from each other, each of said second optical transmission lines intersecting with said plurality of first optical transmission lines at the respective nodes; a plurality of optical processing devices (31) provided in correspondence to each node, each of said optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength pertinent to said device from the input wavelength-multiplexed optical signal for converting said wavelength of the selected optical signal to a second wavelength that is specified by said reference wavelength, said optical processing device further outputting the same on said second optical transmission line connected to the node; and a reference optical beam generator (32) for producing the reference optical beam and supplying the same to the optical processing devices such that the output optical signals outputted on each second optical transmission line have the wavelengths that are different from each other.

Claim 8

An optical matrix switch for switching a wavelength-multiplexed optical beam carrying thereon a number of optical signals of different wavelengths, comprising: a plurality of first optical transmission lines (33₁ - 33 n ) each supplied with an input wavelength-multiplexed optical signal and transmitting the same, said input wavelength-multiplexed optical signal containing therein a plurality of input optical signals with respective wavelengths that are different from each other; a plurality of second optical transmission lines (37₁ - 37 n ) each supplied with an intermediate wavelength-multiplexed optical signal and transmitting the same, said intermediate wavelength-multiplexed optical signal containing therein a plurality of intermediate optical signals with respective wavelengths that are different from each other, each of said second optical transmission lines intersecting with said plurality of first optical transmission lines at the respective first type nodes; a plurality of first group optical processing devices (31) provided in correspondence to each first type node, each of said first group optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength pertinent to said device from the input wavelength-multiplexed optical signal for converting said wavelength of the selected optical signal to a second wavelength that is specified by said reference wavelength, each of said first group optical processing devices further outputting the same on said second optical transmission line connected to the first type node as the optical signal forming the intermediate wavelength-multiplexed optical signal; a plurality of second group optical processing devices (31) provided in correspondence to each second type node, each of said second group optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength pertinent to said device from the intermediate wavelength-multiplexed optical signal for converting said wavelength of the selected optical signal to a third wavelength that is specified by said reference wavelength, each of said second group optical processing devices further outputting the same on said third optical transmission line connected to the second type node; a plurality of third optical transmission lines (34₁ - 34 n ) each supplied with an output wavelength-multiplexed optical signal and transmitting the same, said output wavelength-multiplexed optical signal containing therein a plurality of output optical signals with respective wavelengths that are different from each other, each of said third optical transmission lines intersecting with said plurality of second optical transmission lines at the respective second type nodes; and a reference optical beam generator (32) for producing the reference optical beam and supplying the same to the optical processing devices such that the optical signals in the intermediate wavelength-multiplexed optical signal have the wavelengths that are different from each other and such that the optical signals in the output wavelength-multiplexed optical signal have the wavelengths that are different from each other.

Claim 9

An optical channel switching system for selecting a path of an optical signal in a wavelength-multiplexed optical signal, characterized by: a plurality of input-side optical transmission lines (53₁ - 53 m ) each transmitting a wavelength-multiplexed optical signal; optical distribution means (55₁ - 55 n ) connected to each of said input-side optical transmission lines for distributing the wavelength-multiplexed optical signals to a plurality of output ports, a plurality of optical processing devices (51₁₁ - 51 mn ) connected to the corresponding output ports of the optical distribution means for receiving the wavelength-multiplexed optical signal therefrom, each of said optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength from said wavelength-multiplexed optical signal, said optical processing device further converting the wavelength of the selected optical signal from said predetermined wavelength to another wavelength specified by the reference wavelength, said optical processing device thereby producing an output optical signal; reference optical beam generation means (52) for producing the reference optical beam and supplying the same to the plurality of optical processing devices such that the output optical signals of the optical processing devices have mutually different wavelengths; and optical multiplexing (56₁ - 56 m ) means supplied with the output optical signal from each of the optical processing devices for merging the optical signals to form an output wavelength-multiplexed optical signal.

Claim 10

An optical information transmission system, characterized by: electro-optic conversion means (64) supplied with a plurality of electric signals for converting the same to optical signals having respective wavelengths that are different from each other; optical multiplexing means (65) supplied with said plurality of optical signals for merging the same to form a wavelength-multiplexed optical signal that contains therein input optical signals corresponding to the optical signals of the electro-optic conversion means with respective wavelengths that are different from each other; an optical matrix switch (61) comprising: a plurality of first optical transmission lines each supplied with the wavelength-multiplexed optical signal from the optical multiplexing means as an input wavelength-multiplexed optical signal and transmitting the same; a plurality of second optical transmission lines each supplied with an intermediate wavelength-multiplexed optical signal and transmitting the same, said intermediate wavelength-multiplexed optical signal containing therein a plurality of intermediate optical signals with respective wavelengths that are different from each other, each of said second optical transmission lines intersecting with said plurality of first optical transmission lines at the respective first type nodes; a plurality of first group optical processing devices provided in correspondence to each first type node, each of said first group optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength pertinent to said device from the input wavelength-multiplexed optical signal for converting said wavelength of the selected optical signal to a second wavelength that is specified by said reference wavelength, each of said first group optical processing devices further outputting the same on said second optical transmission line connected to the first type node as the optical signal forming the intermediate wavelength-multiplexed optical signal; a plurality of second group optical processing devices provided in correspondence to each second type node, each of said second group optical processing devices being supplied with a reference optical beam having a reference wavelength and selecting an optical signal having a predetermined wavelength pertinent to said device from the intermediate wavelength-multiplexed optical signal for converting said wavelength of the selected optical signal to a third wavelength that is specified by said reference wavelength, each of said second group optical processing devices further outputting the same on said third optical transmission line connected to the second type node; a plurality of third optical transmission lines each supplied with an output wavelength-multiplexed optical signal and transmitting the same, said output wavelength-multiplexed optical signal containing therein a plurality of output optical signals with respective wavelengths that are different from each other, each of said third optical transmission lines intersecting with said plurality of second optical transmission lines at the respective second type nodes; and a reference optical beam generator for producing the reference optical beam and supplying the same to the optical processing devices such that the optical signals in the intermediate wavelength-multiplexed optical signal have the wavelengths that are different from each other and such that the optical signals in the output wavelength-multiplexed optical signal have the wavelengths that are different from each other; optical distribution means (66) connected to each of the third optical transmission liens for receiving the output wavelength-multiplexed optical signal therefrom and distributing the same to a plurality of output ports; a plurality of filtering devices (67) each connected to the output port of the optical distribution means for separating an optical signal that has a predetermined wavelength from the wavelength-multiplexed optical signal outputted at the output port, said predetermined wavelength being determined for each filtering device; and a plurality of photodetection devices (68) provided in correspondence to said plurality of filtering devices for detecting the optical signal selected by the filtering device and producing an electric signal in response to the detection.