Microscope class notes

How to use a microscope

A microscope is an instrument that is used to magnify small objects.
examples:
Bacterial stains
parasites
Plant organelles

​

What is a microscope?

Typically, a compound microscope is used for viewing samples at high magnification (40 - 1000x), which is achieved by the combined effect of two sets of lenses: the ocular lens (in the eyepiece) and the objective lenses (close to the sample).

​Types of Microscopes

​Compound Light Microscope

• ​Uses a series of lenses to magnify images

• ​Use stains and dyes to see cells better

​Electron Microscope

• ​Create an image with a beam of electrons

• ​Transmission Electron Microscope

• ​Scanning Electron Microscope

• ​Scanning Tunneling Microscope

​Microscope Parts

• ​Ocular Lens

• ​Stage

• ​Objective Lenses

• ​Diaphragm

• ​Coarse Adjustment Knob

• ​Fine Adjustment Knob

• ​Light

​Parts of a Microscope

1. ​Objective Lens = Lens closest to the specimen; directs light to the ocular.

2. ​Ocular = Eyepiece; Lens in eye piece

3. ​Revolving Nosepiece = Holds the objective lenses; allows for adjustment of objective lenses to higher or lower magnification.

​Parts of a Microscope

​4. Stage = holds the specimen to be viewed

​5. Stage Clips = keeps the microscope slide in place

​6. Diaphragm = adjusts the amount of light that passes through the specimen

​7. Light source = source of light on the microscope

​8. Arm = holds the ocular and revolving nosepiece; carry using the arm

​Parts of a Microscope

​9. Coarse Adjustment knob = allows for focus of the specimen at low magnification; only use on low magnification

​10. Fine adjustment knob = used to focus specimen at high magnification

​11. Base = the bottom of the microscope; put one hand under the base to carry

Labelling

Label all the parts of the microscope

Drag labels to their correct position on the image

Light

Stage

Coarse Focus Knob

base

Rotating Nosepiece

Objective Lens

Eye Piece

Fine Focus Knob

Diaphragm

Arm

​How to Focus A Microscope

• Start with lowest power objective lens (eg. 4x)

• Look through the eyepiece and move the coarse adjustment knob until the image comes into focus.

• Move the microscope slide around until the sample is in the center of the field of view (what you see).

• Use the fine adjustment knob to focus with the clearest image