| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a technique for generating a Bessel beam. <P>SOLUTION: An input optical fiber for supporting propagation in a fundamental mode is prepared. The input optical fiber is connected to a fiber mode converting device for providing phase matching at a predetermined excitation wavelength between the fundamental mode and a selected azimuthally symmetric higher-order mode. As an input to the fiber mode converting device, a coherent light beam is fed through the input optical fiber to provide a fundamental mode input at the excitation wavelength. The fiber mode converting device resonantly excites the selected azimuthally symmetric mode. The azimuthally symmetric mode is provided as a beam output from an end face of the fiber mode converting device to approximate a Bessel beam. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
