Phase-only optical pupil filter for improving axial resolution in confocalmicroscopy

In this paper, two kinds of 3-zone phase-only pupil filter for confocal mic roscopy were optimally designed with constrained global optimization(CGO)al gorithm. The CGO method is discussed in detail. The first kind of pupil fil ter can increase the axial resolution while unchanging the transverse resol ution, which can improve the optical-sectioning capacity in confocal micros copy. The second kind of pupil filter can increase the axial and transverse resolution at the same time, which is applicable in 3-dimensional imaging in confocal microscopy.