PHASE DIFFERENCE PINHOLE TYPE OPTICAL ELEMENT AND CONFOCAL MICROSCOPE USING IT

摘要

PROBLEM TO BE SOLVED: To provide a phase difference pinhole type optical element whose depth of focus is deep and which can achieve high resolution and a confocal microscope using it. SOLUTION: This confocal microscope is used for detecting the image of a sample 24 by transmitting a laser beam 12 through a spatial filter 15, condensing them at the sample 24 through an objective lens 21 and transmitting the regular reflected light thereof through the filter 15. Then, a spatial phase filter 20 transmitting the light of the central part and the peripheral part of the laser beam and shifting both of the light by giving the phase difference of 1/2λis made to intervene in the optical path of the beams 12 in the filter 15.