Two-dimensional multi-beam stabilizer and combining systems and methods

• US 9,325,144 B2
• Filed: 02/14/2013
• Issued: 04/26/2016
• Est. Priority Date: 02/14/2012
• Status: Active Grant

• Current Assignee: Panasonic Corporation Of North America (Panasonic Holdings Corporation)
• Original Assignee: TeraDiode, Inc. (Panasonic Holdings Corporation)
• Inventors: Tayebati, Parviz, Chann, Bien
• Primary Examiner(s): Won, Bumsuk
• Assistant Examiner(s): Alexander, William R
• Application Number:
  US13/766,923
• Publication Number:
  US 20150333485A1
• Time in Patent Office: 1,167 Days
• Field of Search: 359/487.04, 372/30, 372/29.02
• US Class Current: 1/1
• CPC Class Codes: G02B 27/1006 for splitting or combining different wavelengths G02B27/1086, G02B27/141 take precedence
• CPC Class Codes: H01S 3/08 Construction or shape of optical resonators or components thereof
• CPC Class Codes: H01S 3/0805 by apertures, e.g. pin-holes or knife-edges
• CPC Class Codes: H01S 3/08054 Passive cavity elements acting on the polarization, e.g. a polarizer for branching or walk-off compensation quarter-wave plates in a Q-switch laser H01S3/1124, H01S3/115
• CPC Class Codes: H01S 3/0826 using a diffraction grating
• CPC Class Codes: H01S 3/139 by controlling the mutual position or the reflecting properties of the reflectors of the cavity , e.g. by controlling the cavity length
• CPC Class Codes: H01S 3/2391 emitting at different wavelengths
• CPC Class Codes: H01S 5/141 using a wavelength selective device, e.g. a grating or etalon H01S5/146 takes precedence
• CPC Class Codes: H01S 5/143 Littman-Metcalf configuration, e.g. laser - grating - mirror
• CPC Class Codes: H01S 5/4012 Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms
• CPC Class Codes: H01S 5/4068 with lateral coupling by axially offset or by merging waveguides, e.g. Y-couplers
• CPC Class Codes: H01S 5/4087 emitting more than one wavelength

Abstract

A system and method for stabilizing and combining multiple emitted beams into a single system using both WBC and WDM techniques.

Claims

1. A multi-beam stabilizer and combining system comprising:

a two-dimensional wavelength stabilizer having a dispersive and non-dispersive dimension comprising;

an array of beam emitters each emitting a beam,

a first dispersive element, and

telecentric optics positioned and having power along the non-dispersive dimension to image the emitted beams onto the first dispersive element,

wherein the first dispersive element (i) reflects a portion of the emitted beams back into each beam emitter, thereby forming a resonator with each beam emitter that stabilizes the beam emitted by each beam emitter to a unique wavelength, and (ii) transmits a portion of the dispersed beams, each transmitted portion having the unique wavelength emitted by the beam emitter associated therewith; and

a wavelength combiner having a dispersive and non-dispersive dimension comprising;

a combining optical element, different from the first dispersive element, arranged to receive the dispersed beams, and cause the beams to converge along a beam combining dimension, and

a second dispersive element, positioned along a beam combining dimension, to receive the plurality of converging beams, and transmit the beams as a multi-wavelength output away from the array of beam emitters.

2. The multi-beam stabilizer and combining system of claim 1, wherein the wavelength stabilizer comprises a transform optic configured to cause the emitted beams along the dispersive dimension to converge towards the first dispersive element.

3. The multi-beam stabilizer and combining system of claim 1, wherein the first dispersive element is a chirped grating.

4. The multi-beam stabilizer and combining system of claim 1, wherein the wavelength combiner comprises a second telecentric optic system having optical power along the non-dispersive dimension and positioned to receive transmitted beams from the first dispersive element and image those beams onto the second dispersive element.

5. A multi-beam stabilizer and combining system comprising:

a two-dimensional wavelength stabilizer having a dispersive and non-dispersive dimension comprising;

an array of beam emitters each emitting a beam,

at least one transform optical element having power in the dispersive dimension placed to receive and cause the beams to converge,

a first dispersive element placed to receive the converging beams from the transform optical element and disperse the beams into at least two orders, wherein one of the orders is transmitted, and

a reflective surface configured to receive the non-transmitted order, reflect the order back onto the first dispersive element, through the transform optical element and into each of the emitters, wherein a resonator is formed between the mirror and a back facet of each of the emitters to thereby stabilize the beam emitted by each beam emitter to a unique wavelength; and

a wavelength combiner having a dispersive and non-dispersive dimension comprising;

a combining optical element, different from the first dispersive element, arranged to receive the transmitted order of beams, and cause the transmitted beams to converge along a beam combining dimension, and

a second dispersive element, positioned along a beam combining dimension, to receive the converging beams, and transmit the beams as a multi-wavelength output away from the array of beam emitters.

6. The multi-beam stabilizer and combining system of claim 5, wherein the wavelength stabilizer comprises telecentric optical elements having power in the non-dispersive dimension placed between the emitters and first dispersive element.

7. The multi-beam stabilizer and combining system of claim 5, wherein the first dispersive element is a transmission grating.

8. The multi-beam stabilizer and combining system of claim 5, wherein the wavelength combiner comprises a collimating optical element having optical power along the dispersive dimension, wherein the collimating optical element is positioned to receive the transmitted beams, collimate the beams and transmit them onto the combining optical element.

9. The multi-beam stabilizer and combining system of claim 5, wherein the wavelength combiner comprises an imaging optical element having power along the non-dispersive dimension, and positioned to receive the transmitted beams form the image of the array of emitters along the non-dispersive dimension onto the second dispersive element.

10. A multi-beam stabilizer and combining system comprising:

a two-dimensional wavelength stabilizer having a dispersive and non-dispersive dimension comprising;

an array of beam emitters each emitting a beam, wherein each emitter has a front facet and a partially reflective back facet,

a first dispersive element, and

telecentric optics positioned having power along both the dispersive and non-dispersive dimension to image emitted beams from the front facet onto the first dispersive element,

wherein the first dispersive element reflects the emitted beams back into each beam emitter, the back facet of each emitter transmitting a portion of a beam therethrough and reflecting a second portion back toward the first dispersive element, thereby forming a resonator, between the first dispersive element and the back facet of each emitter, which stabilizes the beam emitted by each beam emitter to a unique wavelength; and

a wavelength combiner having a dispersive and non-dispersive dimension comprising;

a combining optical element arranged to receive the transmitted dispersed beams from the back facet of each emitter, and cause the beams to converge along a dispersive dimension, and

a second dispersive element, positioned along a dispersive dimension, to receive the plurality of converging beams, and transmit the beams as a combined multi-wavelength output away from the array of beam emitters.

11. A multi-beam stabilizer and combining system comprising:

a two-dimensional wavelength stabilizer having a dispersive and non-dispersive dimension comprising;

an array of beam emitters each emitting a beam,

a polarizing optical element configured to redirect a portion of the emitted beams and transmit another portion of the beams,

a first dispersive element, and

telecentric optics having optical power along the dispersive and non-dispersive dimension that are positioned after the polarizing optical element to image the transmitted beams from the emitters onto the first dispersive element, and wherein the first dispersive element reflects the beams back into each emitter thereby forming a resonator between the first dispersive element and the back facet of each emitter that stabilizes the beam emitted by each beam emitter to a unique wavelength; and

a wavelength combiner having a dispersive and non-dispersive dimension comprising;

a combining optical element, different from the first dispersive element, arranged to receive the dispersed beams from the polarizing optical element, and cause the beams to converge along a beam combining dimension,

a second dispersive element, positioned along a beam combining dimension, to receive the plurality of converging beams, and transmit the beams as a multi-wavelength output away from the array of beam emitters.

12. A method of stabilizing and combining a two-dimensional array of emitters each emitting a beam, the method comprising the steps of:

forming a stabilizer cavity wherein each emitter forms a resonator with an external reflective surface to thereby stabilize the beam emitted by each emitter to a unique wavelength, wherein each beam emitted of the array of emitters is introduced to a dispersive element disposed within the resonator between the array of emitters and the external reflective surface;

transmitting the beams of the stabilizer from the dispersive element into a wavelength combiner comprising at least one combining optical element; and

combining the beams along one dimension to form a multi-wavelength beam output that is transmitted away from the array of emitters.

13. The method of claim 12, wherein the wavelength combiner further comprises a second dispersive element.

14. A multi-beam stabilizer and combining system comprising:

a two-dimensional wavelength stabilizer having a dispersive and non-dispersive dimension comprising;

an array of beam emitters each emitting a beam,

at least one optical element having power in the dispersive dimension placed to receive and converge each beam, and then transmit converging beams,

a first dispersive element placed to receive the converging beams from the optical element and disperse the beams into at least two orders, wherein one of the orders is transmitted as a converging order of beams, and

a reflective surface configured to receive the non-transmitted order, reflect the order back onto the first dispersive element, through the at least one optical element and into each of the beam emitters, wherein a resonator is formed, between the mirror and a back facet of each of the emitters, which stabilizes the beam emitted by each beam emitter to a unique wavelength; and

a wavelength combiner having a dispersive and non-dispersive dimension comprising;

a second dispersive element, different from the first dispersive element, positioned along a beam combining dimension, to receive the plurality of converging beams, and transmit the beams as a multi-wavelength output away from the array of beam emitters.

15. A multi-beam stabilizer and combining system comprising:

an array of beam emitters each emitting a beam;

a central dispersive element configured to disperse the emitted beams into at least 0^th and 1^st orders;

a first transform lens positioned between the dispersive element and the beam emitters, wherein the first transform lens has power along a combining dimension to receive and cause the emitted beams to converge onto the dispersive element;

a first reflective surface;

a second transform lens positioned after the dispersive element at a distance of the combined focal lengths of the first and second transform lenses, wherein the second transform lens receives the 0^th dispersed order, collimates the 0^th order and transmits the 0^th order beams toward the first reflective surface;

a quarter-wave plate positioned between the second transform lens and the first reflective surface, which is configured to rotate beams propagating therethrough by a quarter each pass; and

a second reflective surface positioned to receive and reflect the 1^st order as feedback onto the dispersive element and into each of the emitters, wherein a resonator is formed, between the back facet of each emitter and the second reflective surface, which stabilizes the beam emitted by each beam emitter to a unique wavelength,

wherein the dispersive element transmits a portion of the 1^st order beams reflected by the second reflective surface as a multi-wavelength output beam away from the array of beam emitters, the multi-wavelength output beam further comprising at least a portion of the light reflected by the first reflective surface back to the dispersive element.

16. The multi-beam stabilizer and combining system of claim 15, further comprising telescoping optics having power along a non-dispersive dimension and positioned between the emitters and dispersive element.

17. A multi-beam stabilizer and combining system comprising:

an array of beam emitters each emitting a beam;

a dispersive element;

a first transform lens positioned to receive the emitted beams and cause each beam to overlap onto the dispersive element, wherein a diverging 0^th order, and 1^st order beams are produced;

a first reflective surface; and

a second transform lens configured to receive the 0^th order beams, collimate the 0^th order beams and transmit them onto a first reflective surface, wherein the first reflective surface redirects the collimated 0^th order beams as feedback to the second transform lens, which then causes the feedback to converge onto the dispersive element, wherein (i) a portion of the feedback is directed into the emitters as wavelength-stabilized feedback thereby stabilizing the beam emitted by each beam emitter to a unique wavelength, and (ii) a second portion is directed towards a second reflective surface, wherein a third portion of feedback from the second reflective surface is directed back towards the first reflective surface and a fourth portion of feedback from the second reflective surface is transmitted by the dispersive element,

wherein the fourth portion of feedback from the second reflective surface combines with the 1^st order beam produced by the dispersive element to form a multi-wavelength output beam transmitted away from the array of beam emitters.

18. The multi-beam stabilizer and combining system of claim 17 further comprising expanding optics positioned between the dispersive element and the second reflective surface.

19. The multi-beam stabilizer and combining system of claim 18, wherein the expanding optics comprise at least two lenses having a ratio of focal lengths in the range of 1:

10.

20. The multi-beam stabilizer and combining system of claim 17, wherein the 1^st order beam diffracted by the dispersive element is a combined multi-wavelength stabilized beam along at least one dimension.