As magnifying power is increased, the field of view is decreased. Filter - a colored transparent material placed in the path of illumination to vary the conditions of viewing. Filter mount - an existing slot on the microscope which can hold one of a set of filters in the path of illumination. Finity Correction System - an optical system in which the image is formed only by an objective lens. Focal Length - distance between a principal point and a focal point.
Magnification is determined by the ratio of objective lens focal length and tube lens focal length.
Components - Hoffman condenser, polarizer and Hoffman objectives. Disadvantages - Loss of some resolving power. Huygenian Eyepiece - an eyepiece which effects a certain amount of correction for chromatic difference of magnification in the achromatic objective lens. It reflects light up into the stage opening and onto the specimen. Illumination - the supply of light onto the object under the objective lens.