Title :
Variable numerical-aperture temporal-coherence measurement of resonant-cavity LEDs
Author :
Coutinho, Ricardo C. ; Selviah, David R. ; Oulton, Rupert F. ; Gray, Jonathan W. ; Stavrinou, Paul N. ; Griffiths, Hugh D. ; Parry, Gareth
Author_Institution :
Dept. of Electron. & Electr. Eng., Univ. Coll. London, UK
fDate :
1/1/2003 12:00:00 AM
Abstract :
The first interferometric measurements of temporal-coherence length variation with numerical aperture (NA) are described for 650 nm, resonant-cavity light-emitting diodes (LEDs) agreeing with spectrally derived results. The interferometrically measured coherence length (22 μm to 32 μm) reduced by 37% for a 0.42 increase in NA. For a larger range of NA (0-1), this would give coherence lengths (10 μm-40 μm) lying in the gap between that of conventional LEDs (∼5 μm) and superluminescent diodes (∼60 μm).
Keywords :
light coherence; light emitting diodes; light interferometry; optical resonators; optical testing; 10 micron to 40 micron; 22 to 32 micron; 650 nm; coherence length variation; conventional LEDs; interferometric measurements; interferometrically measured coherence length; numerical aperture; resonant-cavity LEDs; resonant-cavity light-emitting diodes; spectrally derived results; superluminescent diodes; variable numerical-aperture temporal-coherence measurement; Adaptive optics; Coherence; Interferometers; Length measurement; Light emitting diodes; Optical interferometry; Optical modulation; Optical noise; Resonance; Vertical cavity surface emitting lasers;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2003.809130
