Cw organic dye laser

Claim 2

APPARATUS CAPABLE OF STIMULATING THE EMISSION OF CONTINUOUS-WAVE COHERENT RADIATION FROM A FLUORESCENT ORGANIC DYE SOLUTION CONTAINING ORGANIC DYE MOLECULES HAVING A TRIPLETSTATE LIFETIME LESS THAN

Claim 3

The apparatus of claim 1 wherein at least one of said reflective means is at least partially transparent to said excitation radiation for admitting excitation radiation into said portion.

Claim 4

The apparatus of claim 1 wherein said cavity has a substantially hemispherical configuration.

Claim 5

The apparatus of claim 1 wherein said maintaining means comprises a substantially enclosed cell for containing said solution, said cell having a wall which is substantially transparent to said excitation radiation for admitting excitation radiation into said portion.

Claim 6

The apparatus of claim 4 wherein at least one of said reflective means comprises a wall of said cell.

Claim 7

The apparatus according to claim 1 wherein said dissipating means comprises a heat sink positioned in the vicinity of the center of curvature of said effectively concave reflective means.

Claim 8

The apparatus according to claim 1 wherein said cavity has an optical axis and said dissipating means comprises means for flowing said solution in a direction substantially perpendicular to said optical axis.

Claim 9

A laser comprising: an active liquid medium comprising fluorescent organic dye molecules and a triplet quencher for said molecules dissolved in a solvent; an external source of continuous-wave radiation having spectral characteristics adapted to excite the molecules of said liquid medium; means for concentrating continuous-wave radiation from said external source within said liquid medium at a power density sufficient to excite a sufficient number of said organic dye molecules to produce a population inversion, in which radiation is spontaneously emitted by said excited molecules; reflective means comprising a focused resonant cavity for redirecting a predetermined percentage of said emitted radiation back through said liquid medium to sustain laser action; means for dissipating thermal energy from said liquid medium at a rate sufficient to maintain the optical homogeneity of said liquid medium at a level permitting continuous laser action; and means for abstracting said emitted radiation from said cavity for utilization.

Claim 10

A laser comprising: an active liquid medium comprising fluorescent organic dye molecules and a triplet quencher for said molecules dissolved in a solvent; an external source of continuous-wave radiation having spectral characteristics adapted to excite the molecules of said liquid medium; means for concentrating continuous-wave radiation from said external source within said liquid medium at a power density sufficient to excite a sufficient number of said organic dye molecules to produce a population inversion, in which radiation is spontaneously emitted by said excited molecules; reflective means comprising a focused resonant cavity for redirecting a predetermined percentage of said emitted radiation back through said liquid medium to sustain laser action; means for dissipating thermal energy from said liquid medium at a rate sufficient to maintain the optical homogeneity of said liquid medium at a level permitting continuous laser action; and means for abstracting said emitted radiation from said cavity for utilization.

Claim 11

The laser according to claim 8 wherein said dissipating means is operatively coupled with said reflective means.

Claim 12

The laser according to claim 9 wherein said dissipating means comprises a member having a coefficient of thermal conductivity exceeding 3.0 X 10 2 cal/cm - sec. *C.

Claim 13

The laser according to claim 10 wherein said member comprises a material selected from the group consisting of sapphire and diamond.

Claim 14

The laser according to claim 8 wherein said organic dye molecules are selected from the group consisting of rhodamine 6G, rhodamine B, dichlorofluorescein, tetrachlorofluorescein and disodium fluorescein.

Claim 15

The laser according to claim 8 wherein said external source of continuous-wave radiation comprises a continuous-wave laser.

Claim 16

The laser according to claim 8 wherein said solvent comprises water having a deaggregating compound dissolved therein for preventing said organic dye molecules from aggregating.

Claim 17

The laser according to claim 8 wherein said focused resonant cavity comprises a spaced pair of reflective means, at least one of said reflective means being effectively concave toward the other and having an effective radius of curvature not greater than the spacing between said reflective means.

Claim 18

The laser according to claim 15 wherein said dissipating means comprises a heat sink positioned in the vicinity of the center of curvature of said effectively concave reflective means.

Claim 19

The laser according to claim 15 wherein said resonant optical cavity has a substantially hemispherical configuration, the other of said reflective means being a plane mirror positioned in the vicinity of the center of curvature of said effectively concave reflective means.

Claim 22

The method of claim 18 wherein said dissipating step comprises positioning a heat sink in the vicinity of the center of curvature of said effectively concave reflective means.

Claim 23

The method of claim 19 wherein said maintaining step further comprises flowing the medium through said cavity in a direction substantially perpendicular to a line connecting said spaced pair of reflective means.

Claim 24

Apparatus for use with a fluorescent organic dye solution capable of fluorescing over a continuum of wavelengths and a continuous-wave source of radiation having spectral characteristics capable of exciting the molecules of the dye solution to higher vibrational-rotational energy levels, said apparatus comprising: a. a focused resonant cavity including first and second reflective elements spaced from one another, each of said elements being at least partially reflective to the radiation stimulated in said cavity, said reflective elements being shaped to redirect the stimulated radiation back and forth through a diffraction limited waist located between said reflective elements; b. means for positioning such dye solution in the vicinity of said diffraction limited waist; c. means for focusing the excitation radiation emanating from the source of continuous-wave radiation in the vicinity of said diffraction limited waist at a power density sufficient to excite a sufficient number of molecules of the dye solution in said vicinity to produce the critical population inversion required for laser action; d. means for maintaining the optical homogeneity of the dye solution in the vicinity of said diffraction limited waist at the level required to sustain continuous laser action from the dye solution; and e. a tuning means, including a lens and a dispersive element for causing oscillation within said cavity at a single or a few of the fluorescing wavelengths of the dye solution.

Claim 25

Apparatus for use with a fluorescent organic dye solution capable of fluorescing over a continuum of wavelengths and a continuous-wave source of radiation having spectral characteristics capable of exciting the molecules of the dye solution to higher vibrational-rotational energy levels, said apparatus comprising: a. a focused resonant cavity including first and second reflective elements spaced from one another, each of said elements being at least partially reflective to the radiation stimulated in said cavity, said reflective elements being shaped to redirect the stimulated radiation back and forth through a diffraction limited waist located between said reflective elements; b. means for positioning such dye solution in the vicinity of said diffraction limited waist; c. means for focusing the excitation radiation emanating from the source of continuous-wave radiation in the vicinity of said diffraction limited waist at a power density sufficient to excite a sufficient number of molecules of the dye solution in said vicinity to produce the critical population inversion required for laser action; d. means for maintaining the optical homogeneity of the dye solution in the vicinity of said diffraction limited waist at the level required to sustain continuous laser action from the dye solution; and e. a tuning means, including a lens and a dispersive element for causing oscillation within said cavity at a single or a few of the fluorescing wavelengths of the dye solution.

Claim 26

The invention according to claim 21 wherein said optical homogeneity maintaining means comprises means for dissipating thermal energy from the vicinity of said diffraction limited waist at a rate which permits passage of a sufficient percentage of the redirected radiation to sustain laser action.

Claim 27

The invention according to claim 22 wherein said dissipating means comprises means for flowing the dye solution through said cavity in the vicinity of said diffraction limited waist.

Claim 28

Apparatus capable of stimulating the emission of continuous-wave coherent radiation, said apparatus comprising: a fluorescent organic dye solution containing organic dye molecules, said organic dye molecules having a triplet-state lifetime maintainable at a predetermined value less than

Claim 29

Apparatus capable of stimulating the emission of continuous-wave coherent radiation, said apparatus comprising: a fluorescent organic dye solution containing organic dye molecules, said organic dye molecules having a triplet-state lifetime maintainable at a predetermined value less than

Claim 30

The invention according to claim 24 wherein said source of continuous wave radiation comprises a continuous-wave laser, and said active liquid medium has an absorption spectrum at least partially overlapping the emission spectrum of said laser.

Claim 31

The invention according to claim 25 wherein the active medium of said continuous-wave laser comprises argon ions.

Claim 32

A spectrally tunable laser capable of continuouswave operation, said laser comprising: an active liquid medium including fluorescent organic dye molecules dissolved in a deaggregating solvent, which molecules, when excited, undergo transitions during which there is an emission of radiation over a continuum of wavelengths, said solvent being substantially transparent to the radiation absorbed and emitted by the excited dye molecules; a focused resonant cavity having an internal focus and including (1) means for receiving said liquid medium in the vicinity of said internal focus and (2) means for selectively redirecting back to said vicinity a percentage of the amplified radiation, of a predesired wavelength emitted from said received liquid medium, sufficient to produce laser action from said received liquid medium at said predesired wavelength and for transmitting a small percentage of the amplified radiation of said predesired wavelength; an external source of continuous-wave radiation having spectral characteristics adapted to excite said dye molecules of said liquid medium; means for concentrating the continuous wave radiation emanating from said external source in the vicinity of said internal focus and at a power density sufficient to cause said dye molecules in said vicinity to spontaneously emit and amplify radiation; means for preventing the absorption of said amplified radiation by triplet state molecules from reaching a rate sufficient to extinguish laser action; and means for dissipating thermal energy from dye molecules at said vicinity at a rate which maintains an optical homogeneity of said dye molecules which permits passage of a sufficient percentage of said redirected radiation to sustain continuous laser action.

Claim 33

A spectrally tunable laser capable of continuouswave operation, said laser comprising: an active liquid medium including fluorescent organic dye molecules dissolved in a deaggregating solvent, which molecules, when excited, undergo transitions during which there is an emission of radiation over a continuum of wavelengths, said solvent being substantially transparent to the radiation absorbed and emitted by the excited dye molecules; a focused resonant cavity having an internal focus and including (1) means for receiving said liquid medium in the vicinity of said internal focus and (2) means for selectively redirecting back to said vicinity a percentage of the amplified radiation, of a predesired wavelength emitted from said received liquid medium, sufficient to produce laser action from said received liquid medium at said predesired wavelength and for transmitting a small percentage of the amplified radiation of said predesired wavelength; an external source of continuous-wave radiation having spectral characteristics adapted to excite said dye molecules of said liquid medium; means for concentrating the continuous wave radiation emanating from said external source in the vicinity of said internal focus and at a power density sufficient to cause said dye molecules in said vicinity to spontaneously emit and amplify radiation; means for preventing the absorption of said amplified radiation by triplet state molecules from reaching a rate sufficient to extinguish laser action; and means for dissipating thermal energy from dye molecules at said vicinity at a rate which maintains an optical homogeneity of said dye molecules which permits passage of a sufficient percentage of said redirected radiation to sustain continuous laser action.

Claim 34

The laser defined in claim 27 wherein said cavity has an optical axis and said dissipating means comprises means for flowing said liquid medium in a direction substantially perpendicular to said optical axis.

Claim 35

The laser defined in claim 27 wherein said preventing means comprises a triplet quencher for said organic dye molecules.

Claim 36

The apparatus defined in claim 27 wherein both said preventing means and said dissipating means comprise means for flowing said dye solution through said internal focus.