PROCEEDINGS ARTICLE | August 22, 2009
Proc. SPIE. 7430, Laser Beam Shaping X
KEYWORDS: Diffraction, Holograms, Gaussian beams, Interference filters, Spatial light modulators, Wave propagation, Supercontinuum sources, Spatial coherence, Beam propagation method, Light wave propagation
Airy beams are of great interest as a result of their unusual characteristics, they are non-diffracting and also
propagate along a parabolic path due to the presence of a transversal acceleration component. In this paper
the generation of a white light Airy beam is presented, an investigation is also carried out to determine
how the properties of an Airy beam change with the wavelength and spatial coherence of the source. A
supercontinuum source is used in conjunction with a spatial light modulator to produce the Airy beams.
The wavelength dependence study of the Airy beam parameters was carried out by inserting interference
filters into the supercontinuum beam path to select each wavelength. The parameters investigated are
the deflection coefficient of the Airy beam, b0, this quantifies the parabolic path traveled by the beam;
the characteristic length, x0, which is related to the lobe spacing, and lastly the aperture coefficient, a0.
The deflection coefficient and the characteristic length were both found to be wavelength dependent. The
aperture coefficient did not alter as a result of wavelength, however it was found to be dependent on the
spatial coherence, and therefore on the M2 value, of the beam. The other parameters, b0 and x0, are
unaffected by the spatial coherence of the source.
