1
Yasushi Sugaya: Apparatus and method for optical equalization and amplification. Fujitsu, Staas & Halsey, September 22, 1998: US05812710 (77 worldwide citation)

A variable optical attenuator is provided at an input terminal of a rare-earth doped optical fiber. The variable optical attenuator attenuates a multiwavelength light under the control of an AGBC circuit. The rare-earth doped optical fiber, which is excited by an excitation light generated by a ligh ...


2
Yasushi Sugaya, Miki Takeda, Susumu Kinoshita, Terumi Chikama: Multi-wavelength light amplifier. Fujitsu, Staas & Halsey, April 25, 2000: US06055092 (64 worldwide citation)

A multi-wavelength light amplifier includes a first-stage light amplifier which has a first light amplifying optical fiber amplifying a light input, a second-stage light amplifier which has a second light amplifying optical fiber amplifying a first light output from the first-stage light amplifier, ...


3
Yasushi Sugaya, Tomoto Tanaka, Etsuko Hayashi: Optical amplification apparatus utilizing Raman amplification and controlling method thereof. Fujitsu, Staas & Halsey, May 14, 2002: US06388801 (58 worldwide citation)

The present invention aims at providing an optical amplification apparatus for improving noise characteristics by controlling an amplification operation by assuming a noise figure of the overall apparatus and by taking influences of noise light due to Raman amplification into consideration, and a co ...


4
Yasushi Sugaya, Susumu Kinoshita, Hiroshi Onaka, Terumi Chikama: Optical amplifying apparatus. Fujitsu, Helfgott & Karas P C, April 7, 1998: US05737118 (55 worldwide citation)

A computer-controlled optical amplifying apparatus, which includes an optical amplifying unit including an optical amplifying medium and an optical amplifying control unit controlling the optical amplifying unit under the control of a computer. This optical amplifying control unit is constituted by ...


5
Yasushi Sugaya, Susumu Kinoshita: Controller which controls a variable optical attenuator to control the power level of a wavelength-multiplexed optical signal when the number of channels are varied. Fujitsu, Staas & Halsey, February 15, 2000: US06025947 (45 worldwide citation)

An optical amplifying apparatus which includes an optical amplifier, an optical attenuator and a controller. The optical amplifier amplifies a light signal having a variable number of channels. The optical attenuator passes the amplified light signal and has a variable light transmissivity. Prior to ...


6
Etsuko Hayashi, Tomoto Tanaka, Yasushi Sugaya, Miki Onaka: Optical amplifier with pump light source control for raman amplification. Fujitsu, Staas & Halsey, September 23, 2003: US06624926 (41 worldwide citation)

A Raman amplifier for amplifying a wavelength division multiplexed (WDM) light including signal lights wavelength division multiplexed together. The amplifier includes an optical amplifying medium and a controller. The optical amplifying medium uses Raman amplification to amplify the WDM light in ac ...


7
Miki Onaka, Tomoto Tanaka, Etsuko Hayashi, Yasushi Sugaya, Susumu Kinoshita: Optical amplifier for wide band raman amplification of wavelength division multiplexed (WDM) signal lights. Fujitsu, Staas & Halsey, January 21, 2003: US06510000 (39 worldwide citation)

A Raman amplifier providing a wideband gain for use in a wavelength division multiplexing (WDM) optical communication system. In one embodiment, a first optical amplifier Raman amplifies a wavelength division multiplexed signal light in both a first wavelength band and a second wavelength band in ac ...


8
Yasushi Sugaya, Susumu Kinoshita: Multi-wavelength light amplifier. Fujitsu, Staas & Halsey, November 30, 1999: US05995274 (30 worldwide citation)

An optical amplifying apparatus which includes an optical amplifier, an optical attenuator and a controller. The optical amplifier amplifies a light signal having a variable number of channels. The optical attenuator passes the amplified light signal and has a variable light transmissivity. Prior to ...


9
Yasushi Sugaya, Susumu Kinoshita: Controller which controls a variable optical attenuator to control the power level of a wavelength-multiplexed optical signal when the number of channels are varied. Fujitsu, Staas & Halsey, November 7, 2000: US06144485 (27 worldwide citation)

An optical amplifying apparatus which includes an optical amplifier, an optical attenuator and a controller. The optical amplifier amplifies a light signal having a variable number of channels. The optical attenuator passes the amplified light signal and has a variable light transmissivity. Prior to ...


10
Yasushi Sugaya, Susumu Kinoshita: Controller which controls a variable optical attenuator to control the power level of a wavelength-multiplexed optical signal when the number of channels are varied. Fujitsu, Staas & Halsey, October 12, 1999: US05966237 (26 worldwide citation)

An optical amplifying apparatus which includes an optical amplifier, an optical attenuator and a controller. The optical amplifier amplifies a light signal having a variable number of channels. The optical attenuator passes the amplified light signal and has a variable light transmissivity. Prior to ...