Endoscope including fiber delivery of illumination light

A method for delivering light in an endoscope, the method comprising:

• directing therapeutic light and illumination light longitudinally along an optical fiber to a distal portion of an elongated endoscope body, the therapeutic light and the illumination light having different wavelengths;
• directing, with a wavelength-sensitive light separator, the illumination light to exit the optical fiber laterally through a lateral side of the optical fiber at the distal portion of the optical fiber;
• and
• permitting, with the wavelength-sensitive light separator, the therapeutic light to exit the optical fiber longitudinally through a distal end of the optical fiber.

An endoscope, comprising:

• an elongated endoscope body;
• an optical fiber extending along the endoscope body, the optical fiber configured to direct infrared therapeutic light and visible illumination light longitudinally along the optical fiber to a distal portion of the endoscope body;
• and
• an obliquely-angled fiber Bragg grating disposed along a length of the distal portion of the optical fiber, the obliquely-angled fiber Bragg grating configured to reflect at least some of the visible illumination light out of the optical fiber through a lateral side of the optical fiber and transmit the infrared therapeutic light through the obliquely-angled fiber Bragg grating to exit the optical fiber longitudinally through a distal end of the optical fiber.