Variable spectral width optical noise source

Claim 1

An optical noise source comprising: an optical amplifier that produces optical noise by spontaneous emission and emits the optical noise through a first side; a bandpass filter adjacent the first side of the amplifier; reflecting means adjacent the bandpass filter, operative to receive optical noise emitted by the amplifier and filtered by the filter and to reflect said filtered optical noise back into the first side of the amplifier, the amplifier operative to amplify said filtered optical noise and to emit the amplified filtered noise through a second side; and output means adjacent the second side of the amplifier for preventing any optical noise emitted through the second side of the amplifier from returning to the amplifier.

Claim 11

An apparatus or creating optical noise of a predetermined bandwidth comprising: an amplifying means having first and second sides in an optical path for amplifying optical noise components, said amplifying means including means for producing unpolarized optical noise by spontaneous emission and emitting the optical noise through the first side; reflecting means in the optical path on the first side of the amplifying means for reflecting the optical noise produced by the amplifying means back to the amplifying means for one additional amplification; filter means for filtering out optical noise components outside the predetermined optical bandwidth and for passing optical noise components within the predetermined optical bandwidth, located in said optical path between the amplifying means and the reflecting means such that optical noise components passed by the filter means and reflected by the reflecting means are amplified by the amplifying means during said one additional amplification; and a non-reflecting output in said optical path on the second side of the amplifying means for outputting said twice amplified optical noise and for preventing feedback of optical signals emitted through the second side of the amplifying means so that the twice amplified optical noise does not return to the amplifying means and the amplifying means does not lase.

Claim 12

An apparatus or creating optical noise of a predetermined bandwidth comprising: an amplifying means having first and second sides in an optical path for amplifying optical noise components, said amplifying means including means for producing unpolarized optical noise by spontaneous emission and emitting the optical noise through the first side; reflecting means in the optical path on the first side of the amplifying means for reflecting the optical noise produced by the amplifying means back to the amplifying means for one additional amplification; filter means for filtering out optical noise components outside the predetermined optical bandwidth and for passing optical noise components within the predetermined optical bandwidth, located in said optical path between the amplifying means and the reflecting means such that optical noise components passed by the filter means and reflected by the reflecting means are amplified by the amplifying means during said one additional amplification; and a non-reflecting output in said optical path on the second side of the amplifying means for outputting said twice amplified optical noise and for preventing feedback of optical signals emitted through the second side of the amplifying means so that the twice amplified optical noise does not return to the amplifying means and the amplifying means does not lase.