Circular Airy Beam Based on Bandpass Filter

Abstract

A new type of circular Airy beams is demonstrated by using a bandpass filter, in order to enhance the field intensity at the focal point of light beam, based on the angular spectrum representation and the ray optics picture. The specific ring and the key spatial frequency corresponding to the focal point are obtained, via the ray optics picture, to make the initial field concentrate near the specific ring in the real space. It is found that the field intensity at the focal point of the new type circular Airy beams is better enhanced than the common circular Airy beams and the modified circular Airy beams, and the enhancement effect can be tuned via the central spatial frequency, apodization steepness and width of the bandpass filter. The enhanced field intensity gives a very strong gradient force and may find applications on optical manipulation.

Keywords

• Circular Airy beams
• bandpass filter
• structured light
• angular spectrum representation.