A microscope is an instrument used to magnify objects so that greater detail can be distinguished within an object. A microscope can facilitate a science education for students as well as provide an opportunity for hobbyists to learn more about microorganisms and other objects difficult to see with the naked eye. Microscopes can also stimulate interest in science within younger learners. This section on how to choose a microscope will arm you with microscope knowledge and empower you to make an informed purchase decision. We will discuss the different components of the microscope, explain the differences between the two most common microscopes, and finally we will tell you how to choose the appropriate microscope for the end user/application.
We also include a Glossary of more than 70 terms applying to microscopes that may be helpful.
Eyepiece: Also known as ocular, brings image into focus for the eye, can be 10x, 15x, or 20x
Microscope head: Can be monocular (single eyepiece) binocular (two eyepieces) or trinocular (includes port for camera, 2 eyepieces and photoport)
Objective: Collects light from sample and is located above the stage. 4x, 10x, 40x, 100x are most common magnifications. 100x objective is referred to as the oil immersion lens, immersion oil is used with this objective in order to collect light effectively
Stage: Platform below the objective where specimen is viewed. Mechanical stage allows you to move slide right/left and forward/back
Condenser: Focuses light on specimen, located below the stage
Light source: Can be halogen, LED, tungsten, or fluorescent bulb, some economical microscopes have a mirror instead of light
Coarse/fine focus: Bring image into focus, coarse focus is used to bring image in focus initially and fine focus sharpens the image
Compound vs. Stereo Microscope
It is imperative that one understands the differences between stereo and compound microscopes. Compound microscopes are used to view specimens on slides such as a drop of pond water, bacterial smear, or human tissue. Stereomicroscopes are used to view larger objects such as leaves, twigs, stamps, and insects. Stereo microscopes mimic the way your eyes view objects and provide the user with a 3D image of the object. They also provide a larger working distance which allows you to manipulate the object with your hands, such as a circuit board.