Abstract: A switchable dynamic gain-flattened optical amplifier with wide adjustable gain range is provided. Optical signals are amplified through common amplification such that the gain is approximately common to all optical signals. Further, gain specific amplification is then achieved through distinct amplification wherein the optical signal is routed through one of N parallel amplification paths each having its well-designed gain. The amplifier makes use of a control circuit to self-adjust quickly and respond to changes in input conditions, operating conditions of the optical amplifier and gain requirements while maintaining gain flatness and a low noise figure (NF) over a broad optical bandwidth and a wide range of gain levels. The optical amplifier is highly desirable in dense wavelength-division-multiplexed (DWDM) systems for responding to changes in operating conditions due to link loss, pump deterioration, channel add/drop, and network reconfigurations.

Abstract: An arrangement is provided having an optical waveguide, a Chirp grating and an electro-optic material arranged adjacent the Chirp grating, the electro-optic material, for example liquid crystal material, having a refractive index which can be varied by applying an electric field to the material so as to control how the Chirp grating interacts with the optical waveguide. The Chirp grating has a spatial period that increases gradually along a length of the grating. The arrangement may function as a wavelength selective variable reflector, or as a wavelength selective variable attenuator. The optical waveguide may have a region of cladding made of the electro-optic material, with the Chirp grating arranged adjacent the region of cladding to cause a reflection of particular wavelengths of light when propagating within the optical waveguide, the arrangement being adapted to receive the applied electric field which controls how the Chirp grating interacts with the waveguide.

Abstract: A temperature-compensating package for an optical feature such as a fiber grating, a fiber arrangement suitable for use in such a temperature compensating arrangement, methods of manufacture for such packages and arrangements, and methods of temperature compensating an optical feature such as a fiber grating are provided. A precise temperature compensating arrangement can be provided by adjusting the length of two sections of material for any fiber. The arrangement has a first material having a positive coefficient of thermal expansion and a second portion made of a second material having a negative coefficient of thermal expansion, the first and second portions being arranged to form an end-to-end arrangement such that a selected combined coefficient of thermal expansion for the fiber holder results.

Abstract: A fiber optic adaptor is provided which facilitates the connection of either an ST-terminated fiber or an FC-terminated fiber to another FC-terminated fiber, or to some other optical device. The adaptor has a pair of pins mounted on supports connected to an FC coupling receptacle. The pins have extended and retracted positions. When extended, the pins engage the J-shaped slots of the ST-terminated fiber, and when retracted, they are out of the way allowing the FC-terminated fiber to be connected to the receptacle. In another embodiment, an adaptor is provided which facilitates the connection of either an ST-terminated fiber or an SC-terminated fiber to another SC-terminated fiber.