1. Light Microscope: Parts and Function

2. Basic Principles of Light Microscopy
Images are magnified using a system of lenses
Light is passed through image, through lenses and to viewer
Objects being viewed must be transparent to light or internal components will not be visible.
Completely transparent objects may require stain or dye to visualize

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4. 1. Ocular Lens/Eyepiece
Location: Top of the microscope tube, closest to your eye
Function: Provides additional magnification of specimen on slide, usually 10x or 15x.

5. 2. Nosepiece
Location: Towards the top of the microscope, extending over the stage
Function: Holds objective lenses, turns to allow user to select different magnifications

6. 3. Objective Lens(es)
Location: Attached to nosepiece (can range from 1 to 4 different lenses)
Function: Initial point of magnification for specimen on slide; usually range from 4x, to 10x, to 40x
Total Microscope Magnification: Multiply objective lens x ocular lens
Ex. 10x Ocular x 40 x Objective = 400 x magnification total

7. 4. Arm Location: Side/back of microscope
Function: Used as support for microscope parts and connects to base.
Microscope transport: One hand should be held securely on arm and the other held underneath microscope to support weight.

8. 5. Stage
Location: Middle of microscope, attached at back to arm, moveable
Function: A flat platform that is used to place specimens for observation; contains a hole for light to pass through

9. 6. Stage Clips Location: Attached to the top of the stage
Function: Used to hold slides in position on stage

10. 7. Coarse Adjustment Knob
Location: Attached to side of arm, larger of two adjustment knobs
Function: Used to focus the image on the slide. Should only be used as initial magnification when objectives are far away from the stage

11. 8. Diaphragm Location: Attached underneath the stage
Function: Helps to control the amount of light that passes through the opening in stage

12. 9. Illuminator/Light Source
Location: Attached to the top of microscope base
Function: Provides light

13. 10. Fine Adjustment Knob
Location: Attached to side of arm; smaller of two knobs
Function: Used as final focus of specimen, should only be used when stage is close to the objective lenses

14. 11. Base Location: Bottom portion of microscope, attached to arm
Function: Provides support for microscope at the bottom. Hold power switch and light source.