The laser scanning microscope passes a laser beam through an objective lens to illuminate a single point in an object. The photons of light released are passed through a pinhole before being detected by a photomultiplier. It is this system that improves the clarity of the images as all the out-of-focus light has been filtered out. The laser scans across the object and an image is built up pixel by pixel on a screen.
The confocal laser scanning microscope's aim was not to further increase magnification but to make clearer images. It has been able to produce sharp 3D images of a specimen as shown below: