Extended length embedded Bragg grating manufacturing method and arrangement

Claim 1

An arrangement for forming an extended length light redirecting embedded grating in an elongated solid material optical waveguide having a longitudinal axis, comprising: a support; means for supporting the optical waveguide on said support with the longitudinal axis extending in a predetermined direction such that a portion thereof is situated at a predetermined location; means mounted on said support for directing a coherent light beam of a frequency in the ultraviolet range in a predetermined primary path transversely toward the waveguide; a diffraction grating supported on said support such that a section thereof extends through a zone of said primary path that is disposed at a predetermined spacing from the waveguide, said diffraction grating having a dimension normal to said primary path that exceeds the corresponding dimension of said primary path; means for effectuating relative movement along said direction between, said portion and said section in unison, relative to said primary path, with attendant diffraction of said light beam at said diffraction grating into two mutually frequency shifted partial light beams propagating in diverging secondary paths beyond said diffraction grating and toward the waveguide with at least one of said secondary paths being aimed at a region remote from said location; and means, mounted on said support such as to be stationary relative to said directing means and interposed between said diffractive grating and the waveguide, for causing at least the other of said partial light beams to travel toward said location with attendant formation of an interference pattern having respective high intensity fringes which extend through the waveguide at respective positions that are stationary relative to the waveguide to effect refractive index changes at such positions along a length of the waveguide that exceeds that of said portion.

Claim 11

A method of forming an extended length light redirecting embedded grating in an elongated solid material optical waveguide having a longitudinal axis, comprising the steps of supporting the optical waveguide on a support in such a manner that the longitudinal axis thereof extends in a predetermined direction and such that a portion of the waveguide is situated at a predetermined location; directing a coherent light beam of a frequency in the ultraviolet range in a predetermined primary path transversely toward the waveguide; supporting a diffraction grating on the support such that a section thereof extends through a zone of the primary path that is disposed at a predetermined spacing from the waveguide, with the diffraction grating having a dimension normal to said primary path that exceeds the corresponding dimension of said primary path; effectuating relative movement along said direction between said portion and said section in unison, and relative to the primary path, with attendant diffraction of the light beam at the diffraction grating into two mutually frequency shifted partial light beams propagating in diverging secondary paths beyond the diffraction grating and toward the waveguide with at least one of the secondary paths being aimed at a region remote from said location; and causing at least the other of the partial light beams to travel toward said location with attendant formation of an interference pattern having respective high intensity fringes which extend through the waveguide at respective positions that are stationary relative to the waveguide to effect refractive index changes at such positions along a length of the waveguide that exceeds that of said portion.

Claim 12

A method of forming an extended length light redirecting embedded grating in an elongated solid material optical waveguide having a longitudinal axis, comprising the steps of supporting the optical waveguide on a support in such a manner that the longitudinal axis thereof extends in a predetermined direction and such that a portion of the waveguide is situated at a predetermined location; directing a coherent light beam of a frequency in the ultraviolet range in a predetermined primary path transversely toward the waveguide; supporting a diffraction grating on the support such that a section thereof extends through a zone of the primary path that is disposed at a predetermined spacing from the waveguide, with the diffraction grating having a dimension normal to said primary path that exceeds the corresponding dimension of said primary path; effectuating relative movement along said direction between said portion and said section in unison, and relative to the primary path, with attendant diffraction of the light beam at the diffraction grating into two mutually frequency shifted partial light beams propagating in diverging secondary paths beyond the diffraction grating and toward the waveguide with at least one of the secondary paths being aimed at a region remote from said location; and causing at least the other of the partial light beams to travel toward said location with attendant formation of an interference pattern having respective high intensity fringes which extend through the waveguide at respective positions that are stationary relative to the waveguide to effect refractive index changes at such positions along a length of the waveguide that exceeds that of said portion.