Method and apparatus for eliminating dominance or laser oscillations at one wavelength over those at another

Abstract

Abstract Method and apparatus for eliminating in a laser the dominance of laser oscillations at one wavelength of the laser medium over laser oscillations at another wavelength of said laser medium. The cavity of the laser is defined by two mirrors, at least one of which is spherically concave. Helium-neon gas has been mentioned as an example of one laser medium which may be used, and such acts more like a diverging lens upon laser oscillations at 6,401 A. than it does upon laser oscillations at 6,328 A. Because of this effect, if the effective optical spacing between the mirrors of a helium-neon laser is increased from a value at which diffraction losses are low and oscillations at 6,328 A. dominate, a point will be reached at which the diffraction losses for laser oscillations at 6,328 A. become great enough while the diffraction losses for laser oscillations at 6,401 A. remain small enough for laser oscillations at 6,401 A. only to occur. Accordingly, a method and apparatus for obtaining laser oscillations alternately at two closely related wavelengths of a laser medium or alternately at such wavelengths separated by oscillations at both wavelengths are disclosed and achieved by the proper spacing of the opposite mirrors and suitable optical path altering means therebetween.

Inventors

• 👤 William M Strouse
• 👤 Irwin Tobias

Bibliographic Details