Accession Number : ADD015876

Title :   Apparatus and Method for Varying a Bragg Wavelength of a Bragg Grating Formed in an Optical Fiber.

Descriptive Note : Patent Application, Filed 30 Jun 93,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Kersey, Alan D ; Villarruel, C A

Report Date : 30 Jun 1993

Pagination or Media Count : 32

Abstract : An apparatus and method uses a Bragg grating formed in the core of an optical fiber. An element is coupled to the optical fiber and serves to vary a Bragg wavelength (i.e., a wavelength at which reflection occurs) of the Bragg grating by varying a refractive index of the core and/or a cladding of the optical fiber. The element can be an electro-optical element, a magnetooptical element or a chemo-optical element either sensing or being controllably varied, based on an electric signal, a magnetic signal or a presence or absence of a chemical, respectively. Alternatively, a dopant such as a rare-earth ion, can be formed in the core and/or cladding of the optical fiber and irradiated with laser light from a laser pump. A change in absorption spectra from ground state absorption to excited state absorption changes the refractive index of the core and/or cladding so that the Bragg wavelength of the Bragg grating is varied based on an intensity of the laser light.

Descriptors :   *BRAGG SCATTERING, *GRATINGS(SPECTRA), *FIBER OPTICS, *PATENT APPLICATIONS, ABSORPTION, ABSORPTION SPECTRA, CLADDING, FIBERS, GROUND STATE, INTENSITY, IONS, LASERS, LIGHT, REFLECTION, REFRACTIVE INDEX, SIGNALS, SPECTRA, LASER BEAMS, ELECTROOPTICS, GERMANIUM, ELECTROMAGNETIC WAVE PROPAGATION

Subject Categories : Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE