Variable output coupled resonator

Claim 2

A resonator comprising: a mode control cavity defined at one end by a first mirror having a concave reflective surface and at the other end by a second mirror having a convex reflective surface wherein the first and second mirrors are positioned on and symmetrically about an axis through a centerline of the mode control cavity; a power extraction cavity defined at one end by a first retroreflector and at the other end by a first reflector wherein the first retroreflector and the first reflector are positioned on and symmetrically about a beam axis wherein the beam axis does not superpose the axis through the centerline of the mode control cavity; means for optically coupling the mode control cavity and the power extraction cavity; and a cone having a conical reflective surface centrally located within an aperture in the first retroreflector and adapted for coupling the radiation out of the resonator as an output beam having a continuous cross section.

Claim 3

The invention in accordance with claim 1 further including a gain medium disposed in the power extraction cavity symmetrically about the beam axis.

Claim 4

The invention in accordance with claim 2 wherein the gain medium has an annular configuration.

Claim 5

The invention in accordance with claim 1 wherein the surfaces of the first and second mirrors are in optical communication with each other forming a positive branch confocal unstable resonator having large geometric magnification and low Fresnel number.

Claim 6

The invention in accordance with claim 1 wherein the cone is linearly adjustable along the beam axis of the power extraction cavity to intercept a variable portion of a beam of radiation circulating within the resonator to provide an output beam capable of having both variable power and beam diameter.

Claim 7

The invention in accordance with claim 1 further including a second reflector, optically coupled to the mode control cavity with line of sight communication through an aperture in the first reflector, adapted to reflect a portion of a circulating beam of radiation passing out of the mode control cavity back into the mode control cavity.

Claim 8

The invention in accordance with claim 6 wherein the second reflector is a second retroreflector.

Claim 9

The invention in accordance with claim 1 wherein the means for optically coupling the mode control cavity and the power extraction cavity is a turning mirror, positioned on and symmetrically about the axis through the centerline of the mode control cavity, adapted to pass a circulating beam of radiation between the mode control cavity and the power extraction cavity.

Claim 10

The invention in accordance with claim 8 further including means for varying the diameter of a beam of radiation, circulating within the resonator, as the radiation passes between the mode control cavity and the power extraction cavity.

Claim 11

The invention in accordance with claim 9 wherein the means for varying the diameter of a beam of radiation circulating within the resonator includes: a first turning mirror having a convex reflective surface positioned on and symmetrically about the axis through the centerline of the mode control cavity and adapted to expand the radiation passing out of the mode control cavity and of collimating the radiation passing into the mode control region; and a collector mirror having a concave surface adapted to collimate the beam expanding from the convex reflective surface of the turning mirror and directing the collimated beam to the power extraction cavity and of converging the radiation passing from the power extraction cavity and directing the converging radiation to the turning mirror.

Claim 12

The invention in accordance with claim 10 further including a gain medium having an annular configuration and disposed in the power extraction region symmetrically about the beam axis.

Claim 13

The invention in accordance with claim 1 further including activator means for controlling the separation between the first retroreflector and the first reflector to optimize the quality of the output beam.

Claim 14

The invention in accordance with claim 12 wherein the activator means is a piezoelectric activator.

Claim 15

The invention in accordance with claim 1 further including activator means for controlling the separation between the mirrors defining the mode control cavity.

Claim 16

A resonator comprising: a mode control cavity defined at one end by a first mirror having a concave reflective surface and at the other end by a second mirror having a convex reflective surface wherein the first and second mirrors are positioned on and symmetrically about an axis through a centerline of the mode control cavity; a power extraction cavity defined at one end by a first retroreflector and at the other end by a first reflector wherein the first retroreflector and the first reflector are positioned on and symmetrically about a beam axis wherein the beam axis does not superpose the axis through the centerline of the mode control cavity; means for optically coupling the mode control cavity and the power extraction cavity; a second retroreflector, optically coupled to the mode control cavity with line of sight communication through an aperture in the first reflector, adapted to reflect a portion of a circulating beam of radiation passing out of the mode control cavity back into the mode control cavity; and a cone, having a conical reflective surface centrally located within an aperture in the second retroreflector, linearly adjustable along the beam axis of the power extraction cavity to intercept a variable portion of a beam of radiation circulating within the resonator to provide an output beam having a diameter independent of the width of the gain medium and a power level proportional to the area of the reflective surface intercepting the beam of radiation circulating within the resonator.

Claim 17

A resonator comprising: a mode control cavity defined at one end by a first mirror having a concave reflective surface and at the other end by a second mirror having a convex reflective surface wherein the first and second mirrors are positioned on and symmetrically about an axis through a centerline of the mode control cavity; a power extraction cavity defined at one end by a first retroreflector and at the other end by a first reflector wherein the first retroreflector and the first reflector are positioned on and symmetrically about a beam axis wherein the beam axis does not superpose the axis through the centerline of the mode control cavity; means for optically coupling the mode control cavity and the power extraction cavity; a second retroreflector, optically coupled to the mode control cavity with line of sight communication through an aperture in the first reflector, adapted to reflect a portion of a circulating beam of radiation passing out of the mode control cavity back into the mode control cavity; and a cone, having a conical reflective surface centrally located within an aperture in the second retroreflector, linearly adjustable along the beam axis of the power extraction cavity to intercept a variable portion of a beam of radiation circulating within the resonator to provide an output beam having a diameter independent of the width of the gain medium and a power level proportional to the area of the reflective surface intercepting the beam of radiation circulating within the resonator.