초록 ▼

The present invention relates to an in-line optical amplifier that can be coupled to optical fiber, wherein the amplifying medium has a substantially larger mode field than the optical fiber to which it is coupled. The present invention has realized a design to utilize a very high power pump launchi

The present invention relates to an in-line optical amplifier that can be coupled to optical fiber, wherein the amplifying medium has a substantially larger mode field than the optical fiber to which it is coupled. The present invention has realized a design to utilize a very high power pump launching a multimoded signal having approximately 1 W of pump power into a block of erbium doped glass having a mode field diameter orders of magnitude larger than the mode field diameter of erbium doped fiber. This invention provides a relatively inexpensive optical amplifier that is compatible for use in an optical fiber telecommunications system or for other uses. Advantageously, this invention provides a device that does not require unwieldy lengths of erbium doped fiber to form an amplifier. By using a block of glass having a rare earth therein, packaging, temperature stabilizing and temperature tuning of the amplifier also become practicable. Furthermore, a cylindrical block of glass having planar ends, lends itself to applying coatings or filters thereto, thereby forming selective filters at ends of the erbium doped block to allow the pump light in, and the signal light in at opposite ends, while preventing light at the pump wavelength to propagate out with the amplified signal.

대표청구항 ▼

1. An optical amplifier comprising:an optical waveguide for carrying an optical signal to be amplified, the optical waveguide having an output end for launching the optical signal; a substantially collimating lens optically coupled with the output end of the optical waveguide for receiving the optic

1. An optical amplifier comprising:an optical waveguide for carrying an optical signal to be amplified, the optical waveguide having an output end for launching the optical signal; a substantially collimating lens optically coupled with the output end of the optical waveguide for receiving the optical signal and for providing a substantially collimated beam to be amplified, the substantially collimated beam having a substantially larger mode field diameter than the optical signal being carried by the optical waveguide; a block of light transmissive material sized to carry the substantially collimated beam for amplification, the block of light transmissive material being comprised of a gain medium doped with a rare-earth element, the block being disposed to receive the substantially collimated optical beam; a high power pump disposed to impart optical energy to the block; a substantially focusing lens optically coupled with the block of light transmissive material for focusing the amplified substantially collimated beam; and, an output optical waveguide disposed to couple focused light of the optical signal after it has been amplified within the block of light transmissive material.