Summary
Uses lenses and visible light to magnify specimens up to about 1500 times.
In depth
Parts: eyepiece, objective lenses (4x, 10x, 40x, 100x oil), stage, condenser and light source. Total magnification = eyepiece × objective. Focus with coarse then fine adjustments. Wet mounts and prepared slides are used.
Use the lowest power first, then focus up. Keep slides flat and clean lenses. Oil immersion requires special lens. Drawings should be clear with labelled lines.
Key idea: contrast and resolution matter as much as magnification.
A compound light microscope passes light through a thin specimen and uses an objective lens and eyepiece to magnify it. Total magnification is the objective times the eyepiece, usually up to 1000 to 1500 times, and the limit of resolution is about 0.2 micrometres (200 nm), set by the wavelength of light.
It can show cells, nuclei, chloroplasts and large organelles in living or stained samples. Parts include a light source, condenser, stage, coarse and fine focus. Variants include phase contrast, dark-field and DIC, which improve contrast in unstained cells.
Example: Robert Hooke saw cork cells in 1665.
Key idea: more magnification does not reveal more detail beyond the resolution limit.
Frequently asked questions
What is Light Microscope?
Uses lenses and visible light to magnify specimens up to about 1500 times.
Which area of biology covers Light Microscope, and how advanced is it?
Light Microscope is one of the 51 topics in Lab Methods & Biostatistics. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Magnification and Resolution, Confocal Microscopy, Electron Microscopy.
Can you give an example of Light Microscope?
Onion epidermis is stained with iodine to view cells.
What should I learn before Light Microscope?
Light Microscope is a Beginner topic, so no earlier topic is required. Other Beginner topics in Lab Methods & Biostatistics that pair well with it include Scientific Method, Hypothesis, Variables.
What topics are related to Light Microscope?
The closest topics to Light Microscope are Magnification and Resolution, Confocal Microscopy, Electron Microscopy, Staining Techniques. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Light Microscope?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Light Microscope. To practise the whole of Lab Methods & Biostatistics, use the Lab Methods & Biostatistics quiz.
How is Light Microscope different from Magnification and Resolution?
Light Microscope: Uses lenses and visible light to magnify specimens up to about 1500 times. Magnification and Resolution: Magnification enlarges an image, while resolution is the ability to distinguish two close points. Read both side by side and note what each one explains.
How should I study Light Microscope step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Magnification and Resolution and explain the difference aloud. Finally, take the Lab Methods & Biostatistics quiz and come back to this page for any question you miss.