Light microscope
- USES LIGHT WAVES TO SEE SPECIMEN
- SPECIMEN CAN BE VIEWED IN COLOUR
- ARE SMALL AND PORTABLE
COMPOUND MICROSCOPE
- usually monocular
- uses transmitted light
- Specimens viewed must be very small or cut into thin slices
- magnifying power= 40-10000x
DISSECTING MICROSCOPE
- ussualy binocular
- uses transmitted or reflected light
- can view quite large/thick specimens
- magnifying power of 2-40x
Electron microscope
- USES ELECTRONS TO SEE SPECIMEN
- SPECIMEN COLOUR IS NOT VISIBLE
- NOT PORTABLE
- GREATER MAGNIFYING POWER THAN LIGHT MICROSCOPES
SCANNING ELECTRON MICROSCOPE
- used to view the outer surface of the specimen
- specimen can be quite thick
- images appear in 3-D
TRANSMISSION ELECTRON MICROSCOPE
- used to view inner structures of microscope
- specimens viewed must be very small or cut thin
- images are 2-d
Magnify
is the change in apparent size produced by a microscope to enlarge a specimen
Focus
To make an image clearer
Coarse adjustment Screw
Move stage up and down
Focus specimen on low power
Fine adjustment Screw
Final focus on microscope
High & med power
Arm
Joins base and stage to tube and support adjustment screws and used to carry
stage clips
Holds slide firmly in place for observation
Diaphragm and condenser
controls amount of light directed and passing objectives focuses light rays from the light source to the objective
Electric light source
Reflect light upwards through the condenser towards opening on stage
Eyepiece
contains lenses to magnify specimen under observation (10x)
Tube
Holds lense of eyepiece and objectives at the correct distance apart, black inside to prevent reflection
Rotating nosepiece
Holds objectives on rotating disc
Stage
supports slide over the opening which transmits light
Base
Supports weight of microscope
