Apparatus and method for minimizing performance degradation in a laser device

• Main Author: SANDBERG; JON C
• Format: Patent
• Language: English
• Published: 25.05.1999
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES USING STIMULATED EMISSION; ELECTRICITY

Apparatus and method are disclosed for minimizing performance degradation in a laser device having a laser cavity operating in a predetermined spatial mode having predetermined light beam wavefronts within the laser cavity mode. An optically transmissive unit is placed within the laser cavity and has at least one intracavity optical surface that may be positioned at or provides one end of a laser medium that is within the laser cavity with the intracavity optical surface being coincident with the laser mode wavefronts in order to minimize power losses in the laser device due to contamination buildup at the intracavity optical surface. The optic unit may also include a second optical surface that is less exposed to contamination and has a configuration suitable for providing needed focal properties for the optic unit, and one or more of the optical surfaces may have a reflection coating thereon. Contamination buildup on the optical surfaces causes a change in reflectance with an increase in reflectance resulting in power losses in the laser cavity. The effect of increased reflectance is minimized by curvature and/or orientation selection of the intracavity optical surface such that the light reflected from the surface is maintained within the laser cavity as occurs when the surface is coincident with the light beam wavefronts.