ABSTRACT

Light microscopy is an essential technique for the life sciences. It allows for the identification and counting of cells and the observation of cellular growth, development, communication, and death. The compound microscope can produce high magnification ranges by using two lens systems, the objective and eyepiece, to produce two stages of magnification. The resolution of an optical system is limited by both aberrations and diffraction. The best resolution possible with an ordinary light microscope is diffraction limited. New microscopic imaging techniques and technologies are emerging continually, reflecting advances in computers, optics, and biology itself. However, the basic design of the compound microscope remains similar to that of its ancestors of 200 years ago. On an inverted microscope, the sample must either be able to be flipped over or must have an appropriate transparent substrate for imaging through. Illumination is a critical factor in determining the overall performance of the optical microscope.