ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
Experimental measurements in the laboratory have shown a new type of focusing of far ultraviolet light, λ〈1000 A(ring), using tapered capillary tubes similar to those first developed for the near-field scanning optical microscope which we call photon channeling. Silica tubes with taper half angles of ∼0.5°–6° have been tested. An array of capillaries mounted on a rotatable drum placed in front of a collimated photon source obtained from a rare-gas discharge lamp were used. By rotation of the drum, successive capillaries can be brought into alignment, and the photoemission detected by a channeltron-grid detector. The straight capillary intensity shows no significant light guide effect; it simply decreases as the area of the capillary. However, the tapered capillaries show an enhanced transmission (or photon channeling effect). In quantitative agreement with simple numerical estimates, it is found that the transmission enhancement factor varies from ∼10 to 500 times the collimated transmission of a pinhole aperture of the same dimensions with an approximately linear dependence of channeling factor on inverse of the half angle. Useful intensity suitable for photoelectron energy analysis with capillary openings of ∼0.8 μ has been demonstrated. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1145706
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