1. How a microscope works
Microscopes create a magnified image using lenses.
Light from a lamp is reflected by a mirror (1) up through the specimen on a slide on the stage (2).
The specimen must be thin to let lots of light through.
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2. How a microscope works
Light passes through the specimen into one of the objective lenses (3).
A magnified image forms inside the microscope’s tube.
The eyepiece lens (4) magnifies this image again.
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3. How a microscope works
Light passing through the eyepiece lens (4) enters your eye. It forms an image on your retina.
The image can be focused using the focusing knobs (5).
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4. Why is the image reversed and upside down?
If you look at a letter e with a microscope it looks like this:
This happens because lenses refract light.
Light rays passing through the specimen cross over as they go through the objective lens.
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5. When light rays go though the eyepiece lens they bend but do not cross over.
The upside down and side-to-side image created by the objective lens is just magnified.
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6. Using a microscope
Place the specimen directly over the centre of the hole on the stage (directly over the light).
Use clips to hold the slide in place.
Adjust the position of the mirror to reflect light up through the stage.
If you wear glasses, take them off.
Put one eye very close to the eyepiece.
Close or cover the other eye.
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7. How to focus
Select the lowest power objective lens. While looking from the side, turn the coarse focus knob to move the stage as close as possible to the objective lens.
Make sure the specimen does not hit the objective lens.
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8. How to focus
Look through the eyepiece and focus by slowly turning the coarse focus knob to move the stage away from the objective lens.
Once the object comes into view, use the fine focus knob to bring the object into sharp focus.
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