Tunable, multiple frequency laser diode

Claim 2

A multiple frequency external cavity diode laser comprising: a. a diode laser having an output beam; b. a collimating lens positioned in said output beam; c. a diffraction grating positioned to be impinged by said collimated output beam and provide a first order diffraction beam from said output beam; d. reflective means, positioned to be impinged by said first order diffraction beam; e. focus means for bringing said first order diffraction beam to a focus on said reflective means; f. said reflective means having a plurality of reflective areas positioned to reflect only those portions of said focused first order diffraction beam emerging from said diffraction grating at different diffraction angles, whereby the oscillation of said laser is maintained at frequencies corresponding to the diffraction angles of said reflected first order diffraction beams.

Claim 3

A device according to claim 1 wherein said reflective areas are oriented to intercept and reflect two portions of said focused first order diffraction beam whereby said laser simultaneously oscillates at two wavelengths.

Claim 4

A device according to claim 2 further including: mirror support means for translation of said mirror along a first axis, transverse to the optical axis of said first order diffraction beam, whereby the pattern of reflective areas may be moved to intercept different portions of said first order diffraction beam and thereby also provide different operating wavelengths of said laser.

Claim 5

A device according to claim 3 wherein said plurality of reflective areas comprise a "V" shaped pattern.

Claim 6

A device according to claim 4 wherein the legs of the "V" shaped pattern are disposed at equal angles with respect to the axis of translation to provide equal changes in wavelength when said mirror is translated along said first axis.

Claim 7

A device according to claim 3 wherein said reflective areas comprise: a. a first reflective area extending along a line positioned parallel to an axis of translation of said mirror; b. a second reflective area extending along a line positioned at an angle with respect to the axis of translation of said mirror.

Claim 8

A device according to claim 6 wherein said first and second reflective areas are relatively narrow with respect to the width of said collimated first order diffraction beam to provide laser output wavelengths of high spectral purity.

Claim 9

A device according to claim 3 wherein said mirror support means further includes means for translating said mirror along a second axis, disposed at 90 degrees to said first axis and plane parallel therewith, whereby a selected portion of said reflective areas may be moved in a fashion to change the operating wavelengths of said laser while maintaining differences therebetween constant.

Claim 10

A multiple frequency external cavity diode laser comprising: a. a diode laser having an output beam; b. a collimating lens positioned in said output beam; c. a diffraction grating positioned to be impinged by said collimated output beam and provide a first order diffraction beam from said output beam; d. reflective means, positioned to be impinged by said first order diffraction beam; e. focus means for bringing said first order diffraction beam to a focus on said reflective means; f. said reflective means having a plurality of reflective areas positioned to reflect only those portions of said focused first order diffraction beam emerging from said diffraction grating at different diffraction angles, whereby the oscillation of said laser is maintained at frequencies corresponding to the diffraction angles of said reflected first order diffraction beams and wherein said reflective areas are oriented to intercept and reflect two portions of said focused first order diffraction beam whereby said laser simultaneously oscillates at two wavelengths.

Claim 11

A multiple frequency external cavity diode laser comprising: a. a diode laser having an output beam; b. a collimating lens positioned in said output beam; c. a diffraction grating positioned to be impinged by said collimated output beam and provide a first order diffraction beam from said output beam; d. reflective means, positioned to be impinged by said first order diffraction beam; e. focus means for bringing said first order diffraction beam to a focus on said reflective means; f. said reflective means having a plurality of reflective areas positioned to reflect only those portions of said focused first order diffraction beam emerging from said diffraction grating at different diffraction angles, whereby the oscillation of said laser is maintained at frequencies corresponding to the diffraction angles of said reflected first order diffraction beams and wherein said reflective areas are oriented to intercept and reflect two portions of said focused first order diffraction beam whereby said laser simultaneously oscillates at two wavelengths.

Claim 12

A device according to claim 9 further including: mirror support means for translation of said mirror along a first axis, transverse to the optical axis of said first order diffraction beam, whereby the pattern of reflective areas may be moved to intercept different portions of said first order diffraction beam and thereby also provide different operating wavelengths of said laser.

Claim 13

A device according to claim 10 wherein said plurality of reflective areas comprise a "V" shaped pattern.

Claim 14

A device according to claim 11 wherein the legs of the "V" shaped pattern are disposed at equal angles with respect to the axis of translation to provide equal changes in wavelength when said mirror is translated along said first axis.

Claim 15

A device according to claim 12 wherein said reflective areas comprise: a. a first reflective area extending along a line positioned parallel to an axis of translation of said mirror; b. a second reflective area extending along a line positioned at an angle with respect to the axis translation of said mirror.

Claim 16

A device according to claim 13 wherein said first and second reflective areas are relatively narrow with respect to the width of said collimated first order diffraction beam to provide laser output wavelengths of high spectral purity.

Claim 17

A device according to claim 14 wherein said mirror support means further includes means for translating said mirror along a second axis, disposed at 90 degrees to said first axis and plane parallel therewith, whereby a selected portion of said reflective areas may be moved in a fashion to change the operating wavelengths of said laser while maintaining differences therebetween constant.

Claim 18

A multiple frequency external cavity diode laser comprising: a. a diode laser having an output beam; b. a collimating lens positioned in said output beam; c. a diffraction grating positioned to be impinged by said collimated output beam and provide a first order diffraction beam from said output beam; d. reflective means, positioned to be impinged by said first order diffraction beam; e. focus means for bringing said first order diffraction beam to a focus on said reflective means; f. said reflective means having a plurality of reflective areas positioned to reflect only those portions of said focused first order diffraction beam emerging from said diffraction grating at different diffraction angles, whereby the oscillation of said laser is maintained at frequencies corresponding to the diffraction angles of said reflected first order diffraction beams and wherein said reflective areas are oriented to intercept and reflect two portions of said focused first order diffraction beam whereby said laser simultaneously oscillates at two wavelengths. g. mirror support means for translation of said mirror along a first axis, transverse to the optical axis of said first order diffraction beam, whereby the pattern of reflective areas may be moved to intercept different portions of said first order diffraction beam and thereby also provide different operating wavelengths of said laser.

Claim 19

A multiple frequency external cavity diode laser comprising: a. a diode laser having an output beam; b. a collimating lens positioned in said output beam; c. a diffraction grating positioned to be impinged by said collimated output beam and provide a first order diffraction beam from said output beam; d. reflective means, positioned to be impinged by said first order diffraction beam; e. focus means for bringing said first order diffraction beam to a focus on said reflective means; f. said reflective means having a plurality of reflective areas positioned to reflect only those portions of said focused first order diffraction beam emerging from said diffraction grating at different diffraction angles, whereby the oscillation of said laser is maintained at frequencies corresponding to the diffraction angles of said reflected first order diffraction beams and wherein said reflective areas are oriented to intercept and reflect two portions of said focused first order diffraction beam whereby said laser simultaneously oscillates at two wavelengths. g. mirror support means for translation of said mirror along a first axis, transverse to the optical axis of said first order diffraction beam, whereby the pattern of reflective areas may be moved to intercept different portions of said first order diffraction beam and thereby also provide different operating wavelengths of said laser.

Claim 20

A device according to claim 16 wherein said plurality of reflective areas comprise a "V" shaped pattern.

Claim 21

A device according to claim 16 wherein the legs of the "V" shaped pattern are disposed at equal angles with respect to the axis of translation to provide equal changes in wavelength when said mirror is translated along said first axis.

Claim 22

A device according to claim 16 wherein said reflective areas comprise: a. a first reflective area extending along a line positioned parallel to an axis of translation of said mirror; b. a second reflective area extending along a line positioned at an angle with respect to the axis of translation of said mirror.

Claim 23

A device according to claim 16 wherein said first and second reflective areas are relatively narrow with respect to the width of said collimated first order diffraction beam to provide laser output wavelengths of high spectral purity.