Pulsed gas laser

Claim 2

In a pulsed gas laser comprising the combination of a pair of substantially parallel metal electrodes having continuous electrode surfaces defining an elongated arc gap, a gas source for maintaining a lasable gas at lasable pressure in said gap, means cooperating with said electrodes to provide a circuit for applying a fast rise time lasable voltage pulse across said electrode along the length of the gap, and means providing a path to transmit light lengthwise from said path, the improvement wherein said electrodes are supported in open space, the gap between said electrodes and the space between each electrode and surrounding structure being open to said gas at lasable pressure to provide a pressure-bounded arc region over the effective length of said electrodes, the circuit parameters defining a voltage pulse rise time over a substantial length of said gap which is less than the arc initiation time for said gas.

Claim 3

The pulsed laser of claim 1 wherein said electrodes are spaced between 1 and 4 cm apart to form said gap, and each electrode is spaced a distance of at least a major fraction of said gap space from surrounding structure.

Claim 4

The pulsed laser of claim 1 wherein said electrodes comprise edges of sheet-form conductive members.

Claim 5

In a pulsed nitrogen laser comprising the combination of a pair of substantially parallel metal electrodes defining an elongated arc gap, a gas source for maintaining nitrogen at a lasable pressure between about 20 and 40 torr in said gap, means cooperating with said electrodes to provide a circuit for applying a fast rise time lasable voltage pulse across said electrode along the length of the gap, and means providing a path to transmit light lengthwise from said path, the improvement wherein said electrodes are supported in open space, the gap between said electrodes and the space between each electrode and surrounding structure being open to said gas at lasable pressure to provide a pressure-bounded arc region over the effective length of said electrodes, said electrodes being spaced between 1 and 4 cm apart to form said gap, and each electrode being spaced a distance of at least a major fraction of said gap space from surrounding structure.

Claim 6

In a pulsed nitrogen laser comprising the combination of a pair of substantially parallel metal electrodes defining an elongated arc gap, a gas source for maintaining nitrogen at a lasable pressure between about 20 and 40 torr in said gap, means cooperating with said electrodes to provide a circuit for applying a fast rise time lasable voltage pulse across said electrode along the length of the gap, and means providing a path to transmit light lengthwise from said path, the improvement wherein said electrodes are supported in open space, the gap between said electrodes and the space between each electrode and surrounding structure being open to said gas at lasable pressure to provide a pressure-bounded arc region over the effective length of said electrodes, said electrodes being spaced between 1 and 4 cm apart to form said gap, and each electrode being spaced a distance of at least a major fraction of said gap space from surrounding structure.

Claim 7

In a pulsed gas laser comprising the combination of a pair of sheet-form conductive members each having an edge substantially parallel with, spaced from, and opposed to the respective edge of the other to define an elongated arc gap, means exposing said gap to lasable gas at lasable pressure, said sheet-form conductors forming effectively one capacitor plate and lying over and parallel with a third sheet-form conductor, separated therefrom by dielectric means to form a capacitor, a high voltage means adapted to charge said capacitor to bring said first and second conductors to an elevated voltage, switch means for rapidly shorting the capacitor, said switch means connected to the first and third of said sheet-form conductors and adapted to produce a fast-rising voltage step in said first conductor which travels to the gap, forms an arc thereacross and thence proceeds across second conductor while said arc supports lasing, and means providing a path to transmit light lengthwise from said gap, the improvement wherein said pair of edges of said sheet-form conductors are supported in open space, the space between each edge and surrounding structure being open to said gas to provide a pressure-bounded arc region.

Claim 8

In a pulsed gas laser comprising the combination of a pair of sheet-form conductive members each having an edge substantially parallel with, spaced from, and opposed to the respective edge of the other to define an elongated arc gap, means exposing said gap to lasable gas at lasable pressure, said sheet-form conductors forming effectively one capacitor plate and lying over and parallel with a third sheet-form conductor, separated therefrom by dielectric means to form a capacitor, a high voltage means adapted to charge said capacitor to bring said first and second conductors to an elevated voltage, switch means for rapidly shorting the capacitor, said switch means connected to the first and third of said sheet-form conductors and adapted to produce a fast-rising voltage step in said first conductor which travels to the gap, forms an arc thereacross and thence proceeds across second conductor while said arc supports lasing, and means providing a path to transmit light lengthwise from said gap, the improvement wherein said pair of edges of said sheet-form conductors are supported in open space, the space between each edge and surrounding structure being open to said gas to provide a pressure-bounded arc region.

Claim 9

The laser of claim 5 wherein said sheet-form conductors are comprised of solid conductive metal and said edges comprise continuous, elongated electrode surfaces, the circuit parameters providIng a voltage rise time over a substantial length of said gap which is less than the arc initiation time for said gap.

Claim 10

The laser of claim 5 wherein said dielectric means includes a dielectric sheet, said third conductor lying along one face of said dielectric sheet and said first and second conductors lying along respective regions of the oppositelydirected face of said dielectric sheet, said opposed edges of said first and second sheet-form members being spaced substantially from said dielectric means including said sheet to provide an arc-bounding gas space therebetween whereby contact is prevented of the dielectric means by the arc generated at said gap during lasing.

Claim 11

The laser of claim 5 including a gas chamber comprising an elongated hollow tubular member, flanges of said first and second sheet-form conductive members extending as cantilevers into the gas volume of said tubular member, terminating at said edges.

Claim 12

The laser of claim 8 wherein the edges forming said arc gap are spaced apart between 1 and 4 cm, the wall of said tubular member overlying said gap being spaced from said edges a distance equal to at least a major fraction of said arc gap, said means to evacuate said chamber adapted to maintain a predetermined pressure in the range of about 10 to 40 torr therein and said high voltage source adapted to maintain a voltage of between about 15,000 and 30,000 volts across said capacitor.

Claim 13

The laser of claim 5 wherein said sheet-form conductive members are bent into relatively compact form.

Claim 14

The laser of claim 5 wherein said gap is about a meter or longer in length, and said switch means comprises a switch connected to said first conductive member at a point spaced from said gap and from the center line through the center of the length of said conductive member, said switch adapted to generate a voltage step wave of expanding circular form in the substance of said sheet-form member which progressively intercepts said gap, thereby to maintain lasing at remote regions of said gap despite quenching in the initial regions thereof.

Claim 15

In a pulsed gas laser comprising the combination of a pair of substantially parallel elongated electrodes forming an elongated laser gap, said electrodes being electrically connected along their respective lengths to respective first and second sheet-form conductors which extend in opposite directions away from the gap, said sheet-form conductors together forming in effect a capacitor plate with a gap, and a third sheet-form conductor insulated from and extending generally parallel to said capacitor plate forming a capacitor therewith, means to charge the resultant capacitor and means suddenly to discharge said capacitor in a manner providing a lasable arc-producing voltage transversely across said gap, the improvement wherein said capacitor-defining sheet-form conductors are bent about said gap with insulation disposed between overlapping portions of said conductors.

Claim 16

In a pulsed gas laser comprising the combination of a pair of substantially parallel elongated electrodes forming an elongated laser gap, said electrodes being electrically connected along their respective lengths to respective first and second sheet-form conductors which extend in opposite directions away from the gap, said sheet-form conductors together forming in effect a capacitor plate with a gap, and a third sheet-form conductor insulated from and extending generally parallel to said capacitor plate forming a capacitor therewith, means to charge the resultant capacitor and means suddenly to discharge said capacitor in a manner providing a lasable arc-producing voltage transversely across said gap, the improvement wherein said capacitor-defining sheet-form conductors are bent about said gap with insulation disposed between overlapping portions of said conductors.

Claim 17

The laser of claim 12 wherein said first and second conductors are joined to different spaced apart regions of a face of a dielectric sheet, and a third sheet-form conductor is joined to the other face of said sheet, the resultant assembly being flexible and held in curved configuration about said gap, the dielectric sheet and said first and third conductor extending continuously in one rotational direction from the respective electrode, the dielectric sheet and third conductor extending therebeyond in the opposite rotational direction to the second electrode, said dielectric sheet and third conductor being folded in the region of said second electrode and extending therefrom with said second plate in said first rotational direction whereby each of said first and second conductors curves away from the respective electrode in the same rotational direction about said gap.

Claim 18

The laser of claim 13 including two flexible insulating sheets one extending from the point of fold, along the innEr surface of the folded assembly, preventing electrical inter-action between overlapping regions of said third conductor and the other flexible insulating sheet extending from the point of fold along the outer surface of the folded assembly, preventing electrical inter-action between overlapping regions of said first and second conductors.

Claim 19

The laser of claim 12 wherein said gap is disposed in a tubular chamber and said conductors are secured about the exterior of said chamber.

Claim 20

In a pulsed gas laser comprising the combination of a pair of substantially parallel elongated electrodes forming an elongated laser gap, said electrodes being electrically connected along their respective lengths to respective first and second sheet-form conductors which extend in opposite directions away from the gap, said sheet-form conductors together forming in effect a capacitor plate with a gap, and a third sheet-form conductor insulated from and extending generally parallel to said capacitor plate forming a capacitor therewith, means to charge the resultant capacitor and means suddenly to discharge said capacitor in a manner providing a lasable arc-producing voltage transversely across said gap, the improvement wherein said first and second sheet form conductors are connected to a high voltage source, said third sheet form conductor is connected to the ground, and the respective portions of said first and third sheet form conductors are held in a bent configuration with the high voltage conductor lying on the inside and the grounded conductor lying on the outside of the bend, thereby isolating the respective portion of the high voltage pulse forming circuit from the surroundings.

Claim 21

In a pulsed gas laser comprising the combination of a pair of substantially parallel elongated electrodes forming an elongated laser gap, said electrodes being electrically connected along their respective lengths to respective first and second sheet-form conductors which extend in opposite directions away from the gap, said sheet-form conductors together forming in effect a capacitor plate with a gap, and a third sheet-form conductor insulated from and extending generally parallel to said capacitor plate forming a capacitor therewith, means to charge the resultant capacitor and means suddenly to discharge said capacitor in a manner providing a lasable arc-producing voltage transversely across said gap, the improvement wherein said first and second sheet form conductors are connected to a high voltage source, said third sheet form conductor is connected to the ground, and the respective portions of said first and third sheet form conductors are held in a bent configuration with the high voltage conductor lying on the inside and the grounded conductor lying on the outside of the bend, thereby isolating the respective portion of the high voltage pulse forming circuit from the surroundings.