Animation flash link: https://vlab.amrita.edu/repo/BIOTECH/CEL/Light-Microscope/index.swf
Materials Required
Light microscope, prepared glass slide, immersion oil.
Procedure
- Switched on the light source.
- Using rheostat, the brightness of the light is adjusted.
- A microscope slide is placed into the stage; clip it onto the mechanical stage.
- The nosepiece is rotated to the lowest-power objective i.e., 4x objective lens (objective lens with red band).
- The iris diaphragm is adjusted to the largest diameter, allowing the greatest amount of light to pass through.
- The coarse adjustment knob is adjusted until the specimen is in focus.
- The fine adjustment knob is adjusted until the image become clear.
- The iris diaphragm is adjusted to get the clear image.
- The slide is scanned (right to left and top to bottom) at low power to get an overview of the specimen by turning the slide control knob.
- The nosepiece is rotated to the 10x objective (objective lens with yellow band).
- Close the iris diaphragm to 1/4 of the diameter, allowing the greater amount of light to pass through.
- The coarse adjustment knob is adjusted until the specimen is in focus.
- The fine adjustment knob is adjusted until the image become clear.
- Again the light is adjusted by iris diaphragm until the image is clearer.
- The nosepiece is rotated to the 40x objective (objective lens with blue band).
- Close the iris diaphragm to the 1/2 of the diameter, allowing more restriction to the amount of light to passing through when compared with that in the 10X objective.
- The coarse adjustment knob is adjusted until the specimen is in focus.
- The fine adjustment knob is adjusted until the image become clear.
- The light again by iris diaphragm is adjusted until the image is clearer.
- The nose piece is rotated such that the specimen is between 40x and 100x objective.
- Place a small drop of oil on the centre of the slide.
- The nose piece is rotated so that the oil immersion objective touches the oil.
- Only the fine adjustment knob is adjusted until the image become clear.
- The oil immersion (100X) objective is wiped carefully with lens paper to remove all oil.
- The glass slide is removed and clean the microscope.
Difference Encountered in a Real Laboratory.
In an actual laboratory setting, there are certain important steps that are not necessarily applicable in a virtual lab
1. Make sure that the microscope is working properly before starting the experiment.
2. Wipe the back side of the slide using tissue paper.
3. Switch off the light source after finishing the experiment.
4. Always disinfect your work area when you are finished.