Premium
Fibre optic scrambling in light microscopy: A computer simulation and analysis
Author(s) -
REITZ F. B.,
PAGLIARO L.
Publication year - 1994
Publication title -
journal of microscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.569
H-Index - 111
eISSN - 1365-2818
pISSN - 0022-2720
DOI - 10.1111/j.1365-2818.1994.tb03508.x
Subject(s) - scrambling , optics , curvature , perpendicular , numerical aperture , optical fiber , bent molecular geometry , physics , materials science , ray , optical microscope , microscopy , microscope , ray tracing (physics) , tilt (camera) , wavelength , computer science , mathematics , geometry , scanning electron microscope , algorithm , composite material
Summary Optical fibres bent in two mutually perpendicular planes have proven useful for randomizing illumination in light microscopes. These optical scramblers can increase the resolution and/or contrast obtained with several modes of light microscopy. Here, computer simulations are used to investigate several parameters affecting light randomization in curved optical fibres in order to further the theoretical basis for scrambler design. Light passing through 90° bends of optical fibre of varying radii of curvature was modelled by ray tracing in two dimensions, and scrambling mechanisms were observed. The effects of varying the position and angle of entry of light on the phase and direction of propagation of the emergent light were determined. It was found that (a) thorough scrambling does not necessarily require high numerical aperture (NA) entry of light into the fibre, (b) considerable order persists after a single 90° bend of an idealized fibre and (c) a higher degree of scrambling (at the cost of transmission efficiency) is achieved in more tightly curved fibres. The pathlength variations introduced by scrambling proved smaller than typical laser coherence lengths, requiring temporal scrambling (vibrating the fibre).