Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Gain Thresholds for Diffuse Parasitic Laser Modes

Not Accessible

Your library or personal account may give you access

Abstract

High power, high gain lasers are vulnerable to parasitic oscillations, which are unwanted laser modes that rely on stray wall reflections for their optical feedback. Since parasitics reduce power in the intended laser mode and can cause thermal damage to structural hardware, it is important to know the gain threshold required to support parasitics in various laser medium geometries. When the walls are diffusely reflecting, as in many high power laser devices, a diffuse parasitic mode that fills essentially the entire gain medium can form. A differential equation is derived for the radiant intensity of a diffuse parasitic in the absence of diffraction. An expansion in angular functions leads to a Helmholtz-like equation and suitable boundary conditions at the walls. These equations are solved to give the radiant intensity within a rectangular laser region with specified reflectivities at the bounding walls. Limiting cases are discussed and numerical results are given for the diffuse parasitic gain threshold in rectangular gain regions bounded by two, four, or six partially reflecting walls. A computer code is provided for calculating the gain threshold for other combinations of wall reflectivities.

© 1973 Optical Society of America

Full Article  |  PDF Article
More Like This
Calculation of Modulation Transfer Functions of X-Ray Fluorescent Screens

Robert K. Swank
Appl. Opt. 12(8) 1865-1870 (1973)

Three-Dimensional Diffraction Calculations of Laser Resonator Modes

Arthur N. Chester
Appl. Opt. 12(10) 2353-2366 (1973)

Gain Saturation in the CO2 Laser

Yehuda Nachshon and Uri P. Oppenheim
Appl. Opt. 12(8) 1934-1939 (1973)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (4)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (29)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved