Gas laser with discharge conditioning using ultraviolet photons generated in high current density preliminary discharge

Claim 2

A gas laser comprising: means for producing an ultraviolet photon generating preliminary electrical discharge in a first region of a laser gas, said preliminary discharge having a current density of at least about one ampere per cm2; means for producing a main electrical discharge in a second region of said laser gas spaced from and in photon communication with said first region a preselected time after initiation of said preliminary discharge to excite said gas to a lasing condition, said preselected time being at least about 1 Mu sec.; and means disposed adjacent to said second region for providing a laser optical cavity.

Claim 3

A gas laser according to claim 1 wherein said means for producing said preliminary discharge includes an elongated electrode disposed on one side of said first region, a plurality of electrically interconnected electrode segments disposed on an opposite side of said first region and substantially aligned with one another along a direction parallel to the length of said elongated electrode, and means for applying between said interconnected electrode segments and said elongated electroDe an electrical pulse of sufficient voltage and current to produce in said first region an electrical discharge having a current density of at least about one ampere per cm2.

Claim 4

A gas laser according to claim 1 wherein said first region laterally surrounds said second region.

Claim 5

A gas laser comprising: at least a pair of first electrodes disposed adjacent to a first region of a laser gas, means for applying between said first electrodes an electrical pulse of sufficient voltage and current to establish in said first region an ultraviolet photon generating preliminary electrical discharge having a current density of at least about one ampere per cm2; a pair of second electrodes disposed adjacent to a second region of said laser gas spaced from said first region and in photon communication therewith, means for applying between said second electrodes an electrical pulse of sufficient voltage and current to excite said gas to a lasing condition a preselected time after initiation of said preliminary discharge, said preselected time being at least about one Mu sec.; and means disposed adjacent to said second region for providing a laser optical cavity.

Claim 6

A gas laser comprising: at least a pair of first electrodes disposed adjacent to a first region of a laser gas, means for applying between said first electrodes an electrical pulse of sufficient voltage and current to establish in said first region an ultraviolet photon generating preliminary electrical discharge having a current density of at least about one ampere per cm2; a pair of second electrodes disposed adjacent to a second region of said laser gas spaced from said first region and in photon communication therewith, means for applying between said second electrodes an electrical pulse of sufficient voltage and current to excite said gas to a lasing condition a preselected time after initiation of said preliminary discharge, said preselected time being at least about one Mu sec.; and means disposed adjacent to said second region for providing a laser optical cavity.

Claim 7

A gas laser according to claim 4 wherein said pair of second electrodes have respective substantially planar extended surfaces disposed substantially parallel to and facing one another on opposite sides of said second region, and respective electrodes of said pair of first electrodes are disposed substantially coplanar with respective electrodes of said pair of second electrodes on opposite sides of said first region.

Claim 8

A gas laser according to claim 4 wherein said pair of second electrodes have respective substantially planar elongated surfaces disposed parallel to and facing one another on opposite sides of said first region; and said first electrodes include an elongated electrode disposed substantially coplanar with and parallel to one of said second electrodes on one side of said first region, said elongated electrode being substantially coextensive with said one of said second electrodes, and a plurality of electrically interconnected electrode segments disposed substantially coplanar with the other of said second electrodes on an opposite side of said first region, said electrically interconnected electrode segments being substantially aligned with one another along a direction parallel to the length of said elongated electrode, and the end ones of said electrically interconnected electrode segments being substantially aligned with respective ends of said elongated electrode.

Claim 9

A gas laser according to claim 4 wherein said pair of second electrodes have respective extended substantially planar surfaces disposed substantially parallel to and facing one another on opposite sides of said second region, and at least one of said pair of first electrodes is disposed substantially coplanar with one of said second electrodes and extends along a path laterally surrounding said one of said second electrodes.

Claim 10

A gas laser according to claim 4 wherein said pair of second electrodes have respective substantially planar elongated surfaces disposed substantially parallel to and facing one another on opposite sides of said second region; and said first electrodes include an elongated electrode disposed substantially coplanar with one of said second electrodes along a first path laterally surrounding said one of said second electrodes on one side of said first region, and a plurality of electrically interconnected electrode segments disposed along a second path substantially coextensive with said first path and coplanar with the other of said second electrodes on an opposite side of said first region.

Claim 11

A gas laser according to claim 4 wherein said pair of second electrodes are disposed substantially parallel to and facing one another on opposite sides of said second region, at least one of said second electrodes being a grid electrode, and respective electrodes of said pair of firsT electrodes being disposed to face said grid electrode at substantially equidistant locations from said grid electrode on opposite sides of said first region.

Claim 12

A gas laser according to claim 4 wherein said pair of second electrodes are disposed substantially parallel to and facing one another on opposite sides of said second region, at least one of said second electrodes being a grid electrode, and said first electrodes comprise first and second sets of substantially aligned electrically interconnected electrode segments disposed on opposite sides of said first region in a plane substantially parallel to and facing said grid electrode.

Claim 13

A gas laser comprising: at least a pair of first electrodes disposed adjacent to a first region of a laser gas, means incouding a first pulse generator for applying between said first electrodes an electrical pulse of sufficient voltage and current to establish in said first region an ultraviolet photon generating preliminary electrical discharge having a current density of at least about one ampere per cm2; a pair of second electrodes disposed adjacent to a second region of said laser gas spaced from said first region and in photon communication therewith, means including a second pulse generator for applying between said second electrodes an electrical pulse of sufficienl voltage and current to excite said gas to a lasing condition; delay means coupled between said first and second pulse generators for triggering said second pulse generator at a time such that said exciting electrical pulse is applied between said second electrodes a preselected time after initiation of said preliminary discharge, said preselected time being at least about one Mu sec.; and means disposed adjacent to said second region for providing a laser optical cavity.

Claim 14

A gas laser comprising: at least a pair of first electrodes disposed adjacent to a first region of a laser gas, means incouding a first pulse generator for applying between said first electrodes an electrical pulse of sufficient voltage and current to establish in said first region an ultraviolet photon generating preliminary electrical discharge having a current density of at least about one ampere per cm2; a pair of second electrodes disposed adjacent to a second region of said laser gas spaced from said first region and in photon communication therewith, means including a second pulse generator for applying between said second electrodes an electrical pulse of sufficienl voltage and current to excite said gas to a lasing condition; delay means coupled between said first and second pulse generators for triggering said second pulse generator at a time such that said exciting electrical pulse is applied between said second electrodes a preselected time after initiation of said preliminary discharge, said preselected time being at least about one Mu sec.; and means disposed adjacent to said second region for providing a laser optical cavity.

Claim 15

A gas laser according to claim 11 wherein said delay means provides a time delay which is selectively variable between about 1 Mu sec. and about 10 Mu sec.