Abstract Stimulated emission of radiation (laser action) is produced in materials generally classed as dyes and scintillators. A cavity or cell of the dye materials in solid or liquid solution or as a vapor is pumped or excited with 3371 angstroms radiation, focused to a line with a cylindrical lens from a rectangular beam of such radiation produced with a pulsed crossed field nitrogen gas laser. The focused line, which is transverse to the beam produced by the exciting laser, lies near the surface of the dye material in the cell, and the cell is substantially as long as the line. The cell lies within an intensifying optical cavity formed by a 100 percent reflecting mirror and a partially reflecting output mirror, both perpendicular to the line of focus of the pumping radiation. The stimulated emission from the dye material is characterized by a short pulse width and little loss of energy in the coupling between the two lasers. High pulse rates without dye circulation, and high conversion efficiencies of the dyes when so pumped, are obtained. For frequency adjustment the optical cavity substitutes for the 100 percent mirror a grating or Littrow prism at the appropriate angle. Further spectral narrowing is obtained by inserting a tilted Fabry-Perot etalon in the cavity. By using such a frequency tuner and a plurality of dye materials which emit stimulated radiation over different portions of the spectrum, the present device can provide laser radiation over virtually the whole visible spectrum and into the infrared and ultraviolet.
Apparatus according to claim 1 wherein said emitted radiation has a wavelength of 3371 A.
Claim 2
Dependent Claim
27 words
Apparatus according to claim 1 wherein said gas discharge laser emits pulses with a duration of substantially 10 nanoseconds, and a peak power of substantially 100 kW.
Claim 3
Dependent Claim
32 words
Apparatus according to claim 1 wherein said focusing means comprises a cylindrical lens, wherein said rectangular beam is elongated, and wherein said cylindrical lens converges the rectangular beam in the shorter dimension.
Claim 4
Dependent Claim
25 words
Apparatus according to claim 1 wherein said focusing means comprises a cylindrical mirror and said cylindrical mirror converges the rectangular beam in the shorter dimension.
Claim 5
Dependent Claim
14 words
Apparatus according to claim 1 further comprising a transmission filter in said optical cavity.
Claim 6
Dependent Claim
12 words
Apparatus according to claim 6 wherein said transmission filter is an etalon.
Claim 7
Dependent Claim
14 words
Apparatus according to claim 1 wherein said partially reflecting means is a concave mirror.
Claim 8
Dependent Claim
14 words
Apparatus according to claim 1 wherein said partially reflecting means is a convex mirror.
Claim 9
Dependent Claim
15 words
Apparatus according to claim 1 wherein said wavelength selective reflecting means is a diffraction grating.
Claim 10
Dependent Claim
16 words
Apparatus according to claim 1 wherein said cell comprises a solid solution of said laser material.
Claim 11
Dependent Claim
146 words
Method of producing stimulated radiation in lasable dye materials comprising: a. providing a rectangular beam of pumping radiation in pulSe form; b. focusing said rectangular beam substantially to a line of focus; c. positioning a cell of said lasable dye material with said line of focus of pumping radiation therewithin and a surface of said cell parallel to said line and said line of focus located in said lasable dye material adjacent said surface a distance substantially proportional to the pumping energy required to cause said lasable dye material to lase; d. intensifying only stimulated radiation of a predetermined wavelength of the stimulated radiation emitted from said lasable dye material substantially only along said line in an optical cavity having a reflective axis coincident with said line of focus of pumping radiation; and e. extracting only stimulated radiation of said predetermined wavelength from said optical cavity.