Gas laser transmitter

• US 20040125850A1
• Filed: 09/10/2003
• Published: 07/01/2004
• Est. Priority Date: 09/28/2001
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Hongu, Hitoshi, Hayashikawa, Hiroyuki
• Granted Patent: US 7,046,705 B2
• Time in Patent Office: Days
• US Class Current: 372/85
• CPC Class Codes: H01S 3/034 Optical devices within, or forming part of, the tube, e.g. windows, mirrors reflectors having variable properties or positions for initial adjustment of the resonator H01S3/086
• CPC Class Codes: H01S 3/036 Means for obtaining or maintaining the desired gas pressure within the tube, e.g. by gettering, replenishing; Means for circulating the gas, e.g. for equalising the pressure within the tube H01S3/031 takes precedence
• CPC Class Codes: H01S 3/0401 of optical elements being part of laser resonator, e.g. windows, mirrors, lenses
• CPC Class Codes: H01S 3/041 for gas lasers H01S3/0401 takes precedence

Abstract

A laser oscillator comprises a discharge tube for exciting laser medium, at least a pair of mirrors disposed along an optical axis of laser light emitted by the laser gas excited inside the discharge tube, a laser gas passage connected with the discharge tube, laser gas circulation means for circulating the laser gas inside the laser gas passage, and heat control means for controlling heat generated in at least one of the mirrors and the laser gas circulation means.

Claims

1. A laser oscillator comprising:

a discharge tube for exciting laser gas;

at least a pair of mirrors disposed along an optical axis of laser light emitted by the laser gas excited in said discharge tube;

a laser gas passage in connection with said discharge tube;

laser gas circulation means for circulating the laser gas in said laser gas passage and said discharge tube; and

heat control means for responsively controlling heat generated in at least one of said mirrors and said laser gas circulation means.

2. The laser oscillator according to claim 1, wherein said heat control means comprises:

at least a pair of mirror retainers for retaining said pair of mirrors individually;

a cooling element for cooling any of said pair of mirror retainers;

coolant in circulation through inside said cooling element; and

flow rate control means for controlling a flow rate of said coolant.

3. The laser oscillator according to claim 2, wherein said flow rate control means restricts flow of said coolant when laser is not emitted.

4. The laser oscillator according to one of claim 2 and claim 3, wherein said flow rate control means restricts flow of said coolant when heat is not generated in any of said pair of mirror retainers.

5. The laser oscillator according to claim 4 further comprising temperature detection means disposed to any of said pair of mirror retainers, wherein said temperature detection means detects temperature generated in any of said pair of mirror retainers, and said flow rate control means restricts flow of said coolant based on a result of detection by said temperature detection means.

6. The laser oscillator according to one of claim 2 through claim 5 further comprising humidity detection means disposed in the vicinity of any of said pair of mirror retainers, wherein said flow rate control means restricts flow of said coolant when humidity is equal to or higher than a predetermined level.

7. The gas laser oscillator according to claim 1, wherein said laser gas circulation means is provided with a blower unit disposed to said laser gas passage, and

said heat control means comprises a first temperature sensor for measuring a temperature of the laser gas suctioned by said blower unit, a gas supply mechanism for supplying laser gas into said laser gas passage, a gas discharge mechanism for discharging the laser gas from said laser gas passage, and gas pressure controlling means for controlling a pressure of the laser gas inside said laser gas passage based on a signal from said first temperature sensor.

8. The gas laser oscillator according to claim 7, wherein said gas pressure controlling means comprises a controller for controlling said supply mechanism and said discharge mechanism.

9. The gas laser oscillator according to claim 1, wherein said laser gas circulation means is provided with a blower unit disposed to said laser gas passage, and

said heat control means comprises a second temperature sensor for measuring a temperature of the laser gas suctioned by said blower unit, and frequency control means for controlling a driving frequency of said blower unit based on a signal from said second temperature sensor.

10. The gas laser oscillator according to claim 9, wherein said frequency control means includes an inverter for controlling said blower unit.