Optical control apparatus, optical junction apparatus, optical ADM apparatus and optical transmission apparatus having thereof

An optical ADM apparatus inputted with WDM signal light in which a plurality of signal light having wavelengths different from each other are subjected to wavelength division multiplexing and control signal light for separating only separated signal light having a predetermined wavelength included in the WDM signal light and inserting inserted signal light having the predetermined wavelength, said optical ADM apparatus comprising:

• a first optical control apparatus comprising:
• an optical reflector for selectively reflecting only signal light having a specific wavelength in inputted signal light and transmitting signal light having other wavelength and outputting transmitted signal light;
• and
• a saturable absorber inputted with the transmitted signal light for transmitting the transmitted signal light and outputting first output signal light only when an output level of the transmitted signal light is equal to or larger than a predetermined threshold value,
• said first optical control apparatus being configured for outputting the WDM signal light other than the separated signal light in the WDM signal light when light having a second specific wavelength is inputted along with the WDM signal light;
• a signal light separating and inserting unit for outputting multiplexed signal light by multiplexing the inserted signal light with the WDM signal light outputted from the optical control apparatus;
• and
• a second optical control apparatus comprising:
• a second optical reflector for selectively reflecting only signal light having a specific wavelength in inputted signal light and transmitting signal light having other wavelength and outputting transmitted signal light;
• and
• a second saturable absorber inputted with the transmitted signal light for transmitting the transmitted signal light and outputting first output signal light only when an output level of the transmitted signal light is equal to or larger than a predetermined threshold value,
• said second optical control apparatus being configured for outputting the WDM signal light as it is when light having the first specific wavelength is inputted along with the WDM signal light.

An optical ADM apparatus comprising:

• a first optical coupler inputted with WDM signal light in which a plurality of signal light having wavelengths different from each other are subjected to wavelength division multiplexing for dividing the WDM signal light and outputting first divided WDM signal light and second divided WDM signal light;
• a first optical circulator inputted with the first divided WDM signal light from a first port thereof for outputting the first divided WDM signal light to a second port and outputting the first divided WDM signal light inputted from the second port to a third port thereof;
• a first optical reflector inputted with the first divided WDM signal light for selectively reflecting only light having a first specific wavelength, transmitting light having other wavelength and outputting first transmitted WDM signal light;
• a first saturable absorber inputted with the first transmitted WDM signal light for transmitting the first transmitted WDM signal light only when an output level of the first transmitted WDM signal light is equal to or larger than a first threshold value and outputting first output WDM signal light;
• a signal light reflector for selectively reflecting only separated signal light having a predetermined wavelength from the first output WDM signal light, transmitting signal light having other wavelength and outputting transmitted output WDM signal light;
• a nultiplexing unit for synthesizing the transmitted output WDM signal light with inserted signal light having a wavelength the same as a wavelength of the separated signal light and outputting synthesized signal light;
• a second optical reflector inputted with the second divided WDM signal light for selectively reflecting only light having a second specific wavelength, transmitting light having other wavelength and outputting second transmitted WDM signal light;
• a second saturable absorber inputted with the second transmitted WDM signal light for transmitting the second transmitted WDM signal light only when an output level of the second transmitted WDM signal light is equal to or larger than a second threshold value and outputting second output WDM signal light;
• and
• a second optical coupler for outputting to outside inputted multiplexed signal light or the output WDM signal light.

An optical junction apparatus comprising:

• an input port and an output port;
• a divided output port and a divided input port;
• fiber gratings;
• a saturable absorber connected to an output of the fiber gratings;
• a first coupler an input of which is connected to the input port, one output of which is connected to the divided output port and other output of which is connected to an input of the fiber gratings, respectively;
• and
• a second optical coupler one input of which is connected to the saturable absorber, other input of which is connected to the divided input port and an output of which is connected to the output port, respectively;
• wherein the fiber gratings are set to reflect control signal light having a predetermined wavelength and the saturable absorber is set to transmit light only when the signal light and the control signal light are inputted.

An optical ADM apparatus comprising:

• an input port and an output port;
• a divided output port and a divided input port;
• a first saturable absorber;
• a second saturable absorber;
• an optical variable attenuator an input of which is connected to an output of the first saturable absorber;
• and
• first fiber gratings an output of which is connected to an input of the first saturable absorber;
• second fiber gratings an output of which is connected to an input of the second saturable absorber;
• third fiber gratings an input of which is connected to an output of the second saturable absorber;
• a first optical circulator an output of which is connected to the divided output port and other output of which is connected to an input of the second fiber gratings;
• a second optical circulator one input of which is connected to the divided input port and other input of which is connected to an output of the third fiber gratings;
• a first optical coupler an input of which is connected to the input port, one output of which is connected to an input of the first fiber gratings and other output of which is connected to an input of the first optical circulator, respectively;
• and
• a second optical coupler one input of which is connected to an output of the optical variable attenuator and other input is connected to an output of the second circulator and an output of which is connected to the output port;
• wherein the first and the second fiber gratings respectively are set to reflect control signals of predetermined first and second wavelengths and the first and second saturable absorbers are set to transmit light only when signal light and control signal light are inputted.