Systems and methods for amplifying light

An optical coherence tomography (OCT) system with intravascular imaging capability, said OCT system comprising:

• a fiber-optic based imaging catheter;
• and
• an imaging engine connected to the fiber-optic based imaging catheter, said imaging engine comprising a light source and said light source comprising:
• an optical amplifier comprising a gain medium having a peak gain at a near infrared wavelength;
• and
• a reflector in optical communication with the optical amplifier and comprising a wavelength dependent material having a minimum reflectivity at the near infrared wavelength, wherein the reflector inhibits reflection of light at wavelengths at the peak gain and reflects light at wavelengths not at the peak gain, thereby suppressing parasitic lasing.

A method for intravascular imaging, comprising the steps of:

• transmitting light comprising peak gain and non-peak gain wavelengths through a gain medium, wherein the peak gain is at a near infrared wavelength;
• inhibiting substantially all reflection at peak gain wavelengths, thereby allowing amplification of light at non-peak gain wavelengths directing the amplified light to an optical coherence tomography (OCT) system with intravascular imaging capability, said OCT system comprising:
• a fiber-optic based imaging catheter;
• a patient interface module (PIM);
• and
• an imaging engine;
• wherein the fiber-optic based imaging catheter is optically coupled to the PIM and the PIM is optically coupled to the imaging engine.