High Average Power Diode Laser Illuminator. Phase 1/Phase 2.

Abstract

The Phase I effort was directed toward verification of cryogenic laser diode optic technology for optical throughputs of more than one watt average power per fiber. In the test model, 17 diode module/fiber units out of a complement of 28 were operated simultaneously; the bundled fibers formed a 60 by 80 mil source which emitted 21 watts at 9 per cent duty factor through an f 1.6 optical system. The test model circular array configuration imposes disadvantages during fabrication which prevents successful operation of the full complement of module/fiber units. The Phase II task consisted of design studies and experiments to evolve a linear laser diode fiber optic array. An electrical analog model of the array thermal resistance path was constructed to experimentally solve the three-dimensional heat flow problem. A Gallium-Indium eutectic solder which is a liquid at room temperature was developed to provide a high conductivity interface material. Conceptual array designs were examined for modularity, ease of fabrication, and repairability. Sub-array tests using extruded optical quality fibers indicated potential fiber melting due to the insulating vacuum surrounding the array. A theoretical analysis of fiber cooling using a nitrogen gas filled array chamber showed a marked advantage for gas-cooled fibers. The proposed final design is a linear, modular array using equal length metallized fibers in a gas-filled chamber. The source size is 66 x 66 mils using 30 diode/fiber units on 15 modules. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1974
Accession Number
AD0918880

Entities

People

  • Edmund D. Ludwig
  • Steven Eros

Organizations

  • International Business Machines Corporation (Armonk, NY)

Tags

DTIC Thesaurus Topics

  • Conductivity
  • Fabrication
  • Heat Transmission
  • Laser Diodes
  • Lasers
  • Materials
  • Resistance
  • Thermal Resistance
  • Three Dimensional

Readers

  • Phased Array Antenna Design.
  • Pulsed Power and Plasma Physics.
  • Software Engineering

Technology Areas

  • Directed Energy
  • Microelectronics