Orthogonal linear polarization subtraction confocal method for lateral resolution enhancement

Abstract

Confocal microscopy is a valuable tool for modern life science research. Subtraction microscopy can improve the resolution of the confocal system by the simple addition of components, but the image distortion that is produced can be problematic. In this paper, an orthogonal linear polarization subtraction confocal method (OLSCM) is proposed. The OLSCM obtains images using orthogonal linearly polarized illumination separately and obtains the calculated image by subtracting the absolute difference between the images from the arithmetic mean of the images. A resolution improvement of 14.6% without image distortion can be achieved with a pinhole of one airy unit. In addition, we experimented with 60nm gold particles and achieved a resolution improvement of 10.3%. In the OLSCM, solid-shaped and hollow-shaped point spread functions (PSFs) are both calculated from the PSFs of pairs of orthogonal linearly polarized illuminations. A resolution improvement can be achieved by using the subtraction method without image distortion.