An Introduction To Microscopes

A microscope is a device used for viewing microscopic images that would otherwise be invisible to the human eye. This includes things such as the cells which make up our very bodies, bacteria which live on our skin and on our surfaces around our home beneath our notice, and much much more. This is the science of 'microscopy' and it makes for a fascinating and highly rewarding hobby, as well as being a crucial part of the studies of many students who are learning the sciences such as biology, chemistry, physics etc.

Before you can begin microscopy though you will need a microscope and you will need to understand how they work and how to choose between the various microscopes on offer. Microscopes can vary in many ways and choosing the right one for you is not always easy. Here we will look at what a microscope is, how it works, and how you can choose between different microscopes.



Most microscopes that you will buy for hobbyist pursuits or for use in classrooms will be 'light microscopes' which means that they operate by using light. To see, normally we look at light which has bounced off of other objects where some of the light waves on the spectrum have been absorbed (resulting in colours). A light microscope is no different and here the light will shine from the bottom and pass through the object you are viewing which will be on a transparent slide. It will then hit the item you are viewing as well as a mirror underneath it and will return to the microscope to be viewed. The light is then bent within the scope due to the lenses meaning that you see a magnified image.

As mentioned, a light microscope is fine for most uses, however for even more microscopic images you will need an electron microscope which works by rebounding electrons rather than light waves. For higher level education then or for serious research, electron microscopes might be necessary.

The bottom of the microscope which is poised just above the item on the slide is the 'objective'. The top lenses meanwhile are the eyepieces through which you observe the object and here you can get some variation between binocular microscopes, monocular microscopes and trinocular microscopes. This refers to how many lenses there are to look through ?if there are two or more this allows for depth of perception and 3D vision, while at the same time meaning that other people can look at the same image as you so that you might compare notes to ask for assistance.

Other microscopes will use a screen and show the image on there. These are digital microscopes and they are highly practical for allowing you to also save images, send them via e-mail or on a USB stick, or show them to a whole group of people at once.

To use most microscopes you will simply need to place your sample on the slide which will mean sandwiching it between two sheets of small glass, and then put this between the tongs of the microscope. Then you will look through the eyepieces (unless it is a digital microscope in which case you might not have to), turn on the light, and twist a scope to adjust the lens.