Introduction to Microscopes Tara C. Dale September 8, 2008 Kyrene Akimel A-al Middle School

Microscope Definition and Rules A microscope is the basic tool used by all scientists to make objects appear larger. Microscopy is the study of things that are too small to see with the naked eye. Hold a microscope with one hand on the base and another on the arm. Never touch the glass or lenses of a microscope! When you put a microscope away, always place the smallest objective in place and the stage all the way down.

Microscope Types Magnifying Glass – a single lens microscope Light (or compound) microscope – has more than one lens; uses light to magnify specimen Electron microscope – uses electrons to see greater detail than the light microscope; has electromagnetic or electrostatic lenses Other types too but you’ll not use them unless you go into fields such as microbiology or nanotechnology

Specimens and Slides Specimen – the object you are viewing such as the wing of a butterfly Slide – the plastic or glass rectangle that holds the specimen; held in place on the stage by stage clips Cover slip – the plastic or glass square that covers the specimen, protecting it from dust, etc. Hold slides by the sides, not the top and bottom

Viewing Specimens on Slides The first time you look at a new specimen, you ALWAYS begin with the lowest power of magnification possible. Now locate and center the specimen. Then you can increase the magnification. If you can’t find anything on a slide, adjust the amount of light that is shining through the diaphragm. You may have to increase or decrease the amount of white (is it too dark or too bright when you look in the eyepiece). Specimens appear as a mirror image, which means if you move the slide to the left, in the eyepiece it will move to the right and if you move it up, it will appear to go down.

Making Slides Wet Mount Slide – has water; watch for air bubbles! Dry Mount Slide – does not have water; usually does not have a cover slip Cover slips are very fragile! They can cut you! If you break one, let me know. I’ll pick it up and throw it away for you. Don’t clean up a broken cover slip – let me do it for you!!!!!

Viewing Specimens on Slides Images are also mirror images. Images are flipped upside down and backwards. As a reminder: Specimens appear as a mirror image, which means if you move the slide to the left, in the eyepiece it will move to the right and if you move it up, it will appear to go down. If your microscope has a pointer, don’t draw it!

Lenses – in detail Lens – a piece of glass or other transparent substance that is curved to bend light; lens in a pair of eyeglasses Concave – the lens is curved inward to make the object appear smaller; eyeglasses to see nearby Convex – the lens is curved outward to make the object appear larger; human eyes, microscopes, telescopes, and cameras. Also eyeglasses to see far away.