Abstract: Cladding removed from a portion of the optical fiber defines a window exposing the fiber core. A grating having a substantially periodic structure defining a wavelength is moveably positioned in the window, where it can interact with the evanescent field present in the window when optical power is propagating through the fiber. An adjustable positioning fixture holds the grating proximate to the window and operates to change the relative spacing of the fiber core and grating, between: a first position in which the grating is held proximate to the fiber core and substantially interacts with the evanescent field, and a second position in which the grating is held apart from the fiber core and does not substantially interact with the evanescent field.

Abstract: In the wavelength selective fiber optic switch, an optical fiber with a portion of cladding removed defines a window facilitating access to the radially evanescent field present when optical power is propagating through the optical fiber, defining a first transmission path. The cladding removed optical fiber, a secondary optical waveguide, and a grating structure form a grating assisted coupler. An adjustable positioning fixture changes the relative spacing of the fiber core, grating, and output waveguide between a decoupled position and a coupled position. The switch operates, in the decoupled position, to allow optical power to propagate unperturbed through the first transmission path, including optical power at said optical wavelength, and in the coupled position, to extract and reroute optical power at the optical wavelength to propagate through the second transmission path, while leaving unperturbed other wavelengths propagating through the first transmission path.

Abstract: Cladding removed from a portion of the optical fiber defines a window exposing the fiber core. A grating having a substantially periodic structure defining a wavelength is moveably positioned in the window, where it can interact with the evanescent field present in the window when optical power is propagating through the fiber. An adjustable positioning fixture holds the grating proximate to the window and operates to change the relative spacing of the fiber core and grating, between: a first position in which the grating is held proximate to the fiber core and substantially interacts with the evanescent field, and a second position in which the grating is held apart from the fiber core and does not substantially interact with the evanescent field.