COOLERLESS FIBER LIGHT SOURCE DEVICES FOR HARSH ENVIRONMENTS

摘要

A robust broadband ASE (amplified spontaneous emission) fiber light source device outputs a light beam which is little affected by temperature and radiation. The light source device is a single-pass backward or double-pass backward architecture, and has a coolerless pump laser and temperature compensated bandpass reflector. The light source device may have a high pass filtering element disposed between the wavelength division multiplexer thereof and the optical isolator thereof, so as to compensate the effect of the temperature to the mean wavelength of the light beam. The specific band of the temperature compensated bandpass reflector which reflects the light beam, and the band which the high pass filtering element transmits the light beam are within the band which the ASE unit amplifies the light beam, and the high pass filtering element mainly absorbs the light beam outside the specific band.

主权项

1. An environmental robust fiber light source device comprising:
a plurality of optic fiber sections; a coolerless pump laser for providing a first light beam having a mean wavelength in a first band; a wavelength division multiplexer having a first terminal, a second terminal and a common terminal, wherein the first terminal thereof is connected to the pump laser through at least one of the optic fiber sections, the first terminal thereof receives the first light beam, for allowing the first light beam having a mean wavelength in the first band to pass from the first terminal thereof to the common terminal thereof, and allowing a second light beam having a mean wavelength in a second band to pass through from the common terminal thereof to the second terminal thereof; an optical isolator, being a single-pass uni-directional element, having a first terminal and a second terminal, wherein the first terminal thereof is connected to the second terminal of the wavelength division multiplexer through at least one of the optic fiber sections, the first terminal thereof receives the second light beam from the second terminal of the wavelength division multiplexer, for allowing the second light beam to pass through from the first terminal thereof to the second terminal thereof; an amplified spontaneous emission unit, having a first terminal and a second terminal, wherein the first terminal thereof is connected to the common terminal of the wavelength division multiplexer through at least one of the optic fiber sections, for receiving the first light beam having a mean wavelength in the first band and producing an amplifying effect, for producing a third light beam in both directions, to both the first and the second terminal, and the third beam spectral contents falling within the second beam and has no overlap to that of the first beam thereof; and a bandpass reflector having a first terminal and a second terminal, wherein the first terminal thereof is connected to the second terminal of the amplified spontaneous emission unit through at least one of the optic fiber sections, and the second terminal thereof is connected to at least one of the fiber optic sections, the first terminal thereof is configured to receive the third light beam from the second terminal of the amplified spontaneous emission unit, to reflect the third light beam having a mean wavelength in a specific band to the first terminal thereof, and to allow the remaining of the third light beam mean wavelength to pass through from the first terminal thereof to the second terminal thereof; wherein the second terminal of the amplified spontaneous emission unit receives a reflected fourth light beam from the first terminal of the bandpass reflector, for producing part of the second light beam to the first terminal thereof.