| 摘要 |
Although, conventionally, there were two methods, (1) a wave was transmitted through a spiral phase plate and (2) a diffraction grating containing an edge dislocation was used, they incurred complication of a configuration and securement of a larger amount of space and were not efficient because each of the spiral wave generation methods needed an incident wave to be a plane wave and at least one time of imaging is necessary at the time of wave irradiation on an observation object. In order to efficiently generate the spiral wave having a sufficient intensity, a structure of edge dislocation is taken in into a pattern of the zone plate and a spiral pattern containing a discontinuous zone is formed. Moreover, a thickness and a quality of material that change the phase of the wave by an odd multiple of &pgr; are selected for a material of the wave-blocking section in the pattern. |
