Microscopes

• A microscope must accomplish three tasks; produce a magnified image of the specimen, separate details in the image (resolution), and enable details to be visible to the human eye or camera
• The two main categories of microscope are light and electron.
• There are two types of light microscopes; simple and compound
• Simple light microscopes let light pass through 1 lens(es)
• Compound light microscopes have 2 lens(es)
• Stereo microscopes are used to view larger objects, and used for processes like dissections
• Electron microscopes are more powerful than light microscopes
• The two types of electron microscopes are scanning and transmission
• Scanning microscopes reflect off specimen, producing a 3 dimensional view of the specimen's surface features
• Transmission microscopes have electrons pass through the specimen, providing a view of the inner structure
• To determine magnification: multiply magnification of objective lens by magnification of eyepiece lens
• As magnification level increases, the amount of specimen you see, the field of view, gets smaller
• Measurement commonly used for specimen is micrometres (μm)
• When using a low objective lens, focus the image by using the coarse adjustment knob
• When using a high power objective lens, focus the image using fine adjustment knob
• When drawing a biological drawing, you should always use a grey lead pencil, not coloured
• When looking at something under a microscope, it will appear flipped and upside down