Bi-Directional Fiberoptic Coupler Duncan Technologies, Inc., New Castle, CA

1. Innovation Bi-Directional Fiberoptic Coupler - DTI has developed a low cost bi-directional fiberoptic coupler offering many benefits over existing coupler solutions including enhanced efficiency and reduced component count. The bi-directional coupler can be used to simultaneously couple two high-power diode lasers into an optical fiber with no penalty in the fiber size and virtually no added loss relative to existing couplers. It can also be used to couple light into an optical fiber and split off a return signal for feedback sensing. This feedback capability is critical in many fiberoptic sensor applications. The coupler is applicable to wavelength multiplexing in laser systems for communication systems, medical instruments, and specialized sensors. The enhanced capabilities and reduced component costs enable significant cost benefits in large-scale production systems. Bi-Directional Fiberoptic CouplerDuncan Technologies, Inc., New Castle, CA I Bi-Directional Fiberoptic Coupler Diode Laser Manufacturers - The coupler can be used to create diode laser packages that include an integrated visible tracer beam, allowing identification of the invisible high power diode laser beam. This would enable a competitive advantage for diode laser companies by providing this functionality in an OEM product. The coupler can also be used for summing the output of two high power diode laser, either of the same wavelength or two different wavelengths. Medical & Industrial Sensor Market - The coupler can be used to couple light into an optical fiber and split off a return signal for sensing. The coupler, diode laser, and photodetector can be integrated into a single compact hermetic package. Optical Drive Optic - The coupler can be used in optical disk drives in the read or read/write head optical chain. The coupler focuses the beam onto the disk surface and feeds back the read signal. This single component can replace a series of components that perform the same function in current drives. Accomplishments To date, the coupler has been manufactured in small production runs. The compnoent can easily be produced at low cost in volumeat optics fabrication facilites. The cost benefits and performance may be further enhanced by adapting the design for the use of molded plastic optics.Integration of the coupler into a laser ignition system for hydrogen/oxygen reaction control system thrusters on space vehicles. The coupler was used to couple the output of a high power diode laser source into a fiber for delivery to the igniter, provide a return signal to measure ignition target temperature, and verify system operational status. The system was fabricated and tested in an altitude chamber using a laboratory version of the hydrogen/oxygen thruster developed by Rockwell to provide positional control for the Space Station. Commercialization The Bi-Directional Fiber-Optic Coupler has one patent application on file. Potential market sectors include: Fiberoptic Communications - The bi- directional coupler can be used to couple output from two different wavelength diode lasers into a single optical fiber.This type of wavelength division multiplexing (WDM) is useful in fiberoptic network products. A key feature is virtually no loss penalty in coupling two lasers into a fiber. This enables WDM without significant loss so the spacing between repeaters can remain the same as in single wavelength systems. Government/Science Applications The Bi-Directional Fiberoptic Coupler is an integral part of the compact diode laser package that is a part of DTI's Laser igniter system. This system provides optical ignition and ignition verification of hydrogen/oxygen reaction control system thrusters. The igniter system has potential for application on hydrogen/oxygen engines for reaction control system thrusters and primary propulsion including the SSME. NASA Field Center Date of Update:- April 20, 1998 Success Story # 09-003 Points of Contact: - NASA:-Collin Hieger:-281-483-1803 - Flogiston:- Brian Park:-512 894 0562 1993 SBIR Phase II; NAS # NAS9-19316