Abstract: An external-cavity tunable laser with a flexible wavelength grid tuning function comprises a resonant cavity, collimating lenses, an optical isolator, and an output optical fiber. The resonant cavity comprises a semiconductor gain chip, a beam expander collimating lens, a combined liquid crystal tunable filter assembly, and a reflecting mirror. A current injected to the semiconductor gain chip is converted to broadband spontaneously radiating photons through electrical-to-optical conversion, and the photons are spread along a waveguide toward two sides. A part of photons with special frequencies go back and forth multiple times in the resonant cavity to form a laser after a threshold condition is met. The laser is collimated by the collimating lens, passes through the optical isolator, is coupled by the collimating lens, and enters the output optical fiber.

Abstract: A wavelength selective switch (WSS) with hitless switching. The WSS includes the fiber collimator array, the focusing lens, collimating lens, diffraction grating, focusing lens, and attenuation reflection unit array. Each attenuation reflection unit has an interconnected transmission-type MEMS attenuator and a one-dimension MEMS reflector. The transmission-type MEMS attenuator is positioned in the front of the one-dimension MEMS reflector. The central axis of the transmission-type MEMS attenuator aligns and coincides with that of the one-dimension MEMS reflector, with the two central axes being glued together. The WSS of the present invention effectively utilizes the combination of a one-dimension reflector array and a transmission-type optical attenuator chip. With the use of one-dimension reflector array, instead of the known two-dimension reflector array, the complexity of design and manufacture is greatly reduced, thereby reducing the production costs of the switch.

Abstract: A wavelength selective switch (WSS) with hitless switching. The WSS includes the fiber collimator array, the focusing lens, collimating lens, diffraction grating, focusing lens, and attenuation reflection unit array. Each attenuation reflection unit has an interconnected transmission-type MEMS attenuator and a one-dimension MEMS reflector. The transmission-type MEMS attenuator is positioned in the front of the one-dimension MEMS reflector. The central axis of the transmission-type MEMS attenuator aligns and coincides with that of the one-dimension MEMS reflector, with the two central axes being glued together. The WSS of the present invention effectively utilizes the combination of a one-dimension reflector array and a transmission-type optical attenuator chip. With the use of one-dimension reflector array, instead of the known two-dimension reflector array, the complexity of design and manufacture is greatly reduced, thereby reducing the production costs of the switch.

Abstract: An integrated optical-power adjustable WDM is provided, which has a plurality of channels, each channel having a first input port, a second output port and a third output port, the second output port of one channel being connected to the first output port of the next channel, the first port of each channel having a waveguide, the third port of each channel having a waveguide, each channel comprising a pair of collimating elements composed of a first collimating element and a second collimating element, a thin film filter and a tunable optical filter chip functioning as a variable optical attenuator, wherein the tunable optical filter chip is set between the thin film filter and the third output port for each channel, thereby the respective tunable optical filter chip is integrated into the corresponding internal optical path for each channel of WDM to achieve optical-power control for each channel of the WDM.

Abstract: An integrated optical-power adjustable WDM is provided, which has a plurality of channels, each channel having a first input port, a second output port and a third output port, the second output port of one channel being connected to the first output port of the next channel, the first port of each channel having a waveguide, the third port of each channel having a waveguide, each channel comprising a pair of collimating elements composed of a first collimating element and a second collimating element, a thin film filter and a tunable optical filter chip functioning as a variable optical attenuator, wherein the tunable optical filter chip is set between the thin film filter and the third output port for each channel, thereby the respective tunable optical filter chip is integrated into the corresponding internal optical path for each channel of WDM to achieve optical-power control for each channel of the WDM.