Resonant pumped short cavity fiber laser

An optical gain apparatus comprising:

• an optical pump source generating optical pump energy having a time-varying intensity and directing it in a first direction along an optical path;
• an optical gain medium capable of being pumped by optical energy at a pump wavelength, the gain medium receiving optical pump energy directed in the first direction along the optical path;
• a resonant pumping cavity that resonates optical pumping energy through the optical gain medium while reflecting a portion of the pump energy that is directed toward the gain medium, the reflected energy following a direction opposite the first direction such that the reflected optical energy interacts with the pump energy, the reflection being such that a phase shift between the time-varying intensity of the optical pump energy and a time-varying intensity of the reflected optical energy is minimized when the pump energy has a primary wavelength equal to the pump wavelength;
• a detector that detects optical energy that has been reflected by the resonant pumping cavity and has interacted with the pump energy, and converts it to a feedback signal indicative of said phase shift;
• and
• a feedback apparatus that provides an input signal to the optical pump source in response to the feedback signal, the input signal causing the output wavelength of the optical source to be adjusted toward the pump wavelength.

An optical source for providing a wavelength-stabilized optical output to a resonant pumping cavity that resonates optical pumping energy through an optical gain medium and from which a small amount of optical energy is reflected back toward the source, the reflection being such that a phase shift between a time-varying intensity of the optical energy directed toward the resonsant pumping cavity and a time-varying intensity of the reflected optical energy is minimized when a primary wavelength of the optical energy directed toward the resonant pumping cavity is centered about a peak reflectivity wavelength of the resonant pumping cavity, the optical source comprising:

• an optical signal generator generating optical source energy having a time-varying intensity and directing it toward the resonant pumping cavity;
• a detector that detects optical energy reflected from the cavity and converts it to a feedback signal indicative of said phase shift;
• and
• a feedback apparatus that provides an input signal to the optical signal generator in response to the feedback signal, the input signal causing the output wavelength of the optical signal generator to be adjusted toward the particular wavelength.

A method for generating a wavelength-stable optical signal, the method comprising:

• generating, with an optical generator, optical source energy having a timevarying intensity and directing it in a first direction along an optical path;
• reflecting a portion of the source energy from a resonant pumping cavity that pumps a gain medium. the reflection being in a direction opposite the first direction such that the reflected optical energy interacts with the source energy, the reflection being such that a phase shift between the time-varying intensity of the optical source energy and a time-varying intensity of the reflected optical energy is minimized when the source energy has a particular primary wavelength;
• detecting optical energy that has been reflected by the resonant pumping cavity and has interacted with the source energy, and converting it to a feedback signal indicative of said phase shift;
• and
• directing the feedback signal to a feedback apparatus that provides an input signal to the optical generator in response to the feedback signal, the input signal causing the output wavelength of the optical generator to be adjusted toward the particular wavelength.

A method of providing an amplified optical signal output, the method comprising:

• generating, with an optical pump source, optical pump energy having a time-varying intensity and directing it in a first direction along an optical path toward a resonant pumping cavity that resonates optical energy at a pump wavelength through an optical gain medium;
• reflecting a portion of the pump energy that is directed toward the resonant pumping cavity, the reflected energy following a direction opposite the first direction such that the reflected optical energy interacts with the pump energy, the reflection being such that a phase shift between the time-varying intensity of the optical pump energy and a time-varying intensity of the reflected optical energy is minimized when the pump energy has a primary wavelength equal to the pump wavelength;
• detecting optical energy that has been reflected and has interacted with the pump energy, and converting it to art feedback signal indicative of said phase shift;
• and
• providing an input signal to the optical pump source in response to the feedback signal so as to cause the output wavelength of the optical pump source to be adjusted toward the pump wavelength.

A method of providing wavelength-stabilized optical energy to a resonant pumping cavity that pumps an optical gain medium and from which a small amount of the optical energy is reflected, the reflection being such that a phase shift between a time-varying intensity of the optical energy directed toward the resonant pumping cavity and a time-varying intensity of the reflected optical energy is minimized when a primary wavelength of the optical energy directed toward the resonant pumping cavity is centered about a particular wavelength, the method comprising:

• generating, with an optical signal generator, optical source energy having a time-varying intensity and directing it toward the resonant pumping cavity;
• detecting optical energy reflected from the resonant pumping cavity and converting it to a feedback signal indicative of said phase shift;
• and
• providing an input signal to the optical signal generator in response to the feedback signal, the input signal causing an output wavelength of the optical signal generator to be adjusted toward the particular wavelength.