title: Spot size reduction in coupling of laser to micromanipulator in laser microsurgery by fiberoptic link.
abstract: OBJECTIVE
  In coupling laser with micromanipulator through fiberoptics, the resulting diameter of the spot is limited by the laws of geometrical optics, because of the high numerical aperture (N.A.) of fiberoptic radiation. A new method for the reduction of spot size diameter is suggested.
  
  
  METHODS
  The output of a 2 mW He-Ne laser was couped via fiberoptic link, the fiberoptic output light collected by a single lens collimator and directed to the input of the micromanipulator.
  
  
  RESULTS
  The spot size can be considerably reduced by the introduction of an aperture which reduces the numerical aperture (N.A.) of the fiberoptic. The resulting reduction in total power has little effect on the power density.
  
  
  CONCLUSIONS
  This approach to the collimator design permits reduction in spot size without any significant changes in power density, thus avoiding damage to the tissue and obtaining optimum performance from the micromanipulator.
authors.affiliation: Medical Division, Reliant Technologies Inc., Foster City, California 94404, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Logunov
authors.forename: V G
authors.initials: VG
authors.lastname: Lemberg
mesh_terms: D000465:Algorithms; D004867:Equipment Design; D005336:Fiber Optic Technology / Q000295:instrumentation; D006371:Helium; D053685:Laser Therapy / Q000295:instrumentation*; D007834:Lasers / Q000145:classification; D007909:Lenses; D008846:Micromanipulation / Q000295:instrumentation*; D008866:Microsurgery / Q000295:instrumentation*; D009356:Neon; D013499:Surface Properties
chemical_list: D006371:Helium; D009356:Neon