The Microscope
Microscopes Zacharias Janssen, Robert Hooke and Anton von Leeuwenhoek all contributed to the design of the compound light microscope With the invention of the microscope came many ground breaking discoveries about how life looked on a cellular level Things that were “invisible” are now visible!
How a Microscope Works Microscopes use convex lenses are made of curved glass (and glasses etc.) Convex Lenses bend light and focus it in one spot.
How a Microscope Works Ocular Lens (Magnifies Image) Objective Lens (Gathers Light, Magnifies And Focuses Image Inside Body Tube) Body Tube (Image Focuses)
The Parts of a Microscope
Ocular Lens Body Tube Revolving Nose Piece Arm Objective Lenses Stage Stage Clips Coarse Adjustment knob Diaphragm Fine Adjustment knob Light Source Base Skip to Magnification Section
Body Tube The body tube holds the objective lenses and the ocular lens at the proper distance Diagram
Nose Piece The revolving nose piece holds the objective lenses and can be turned to increase the magnification Diagram
Objective Lenses The Objective Lenses increase magnification (low is 4x, Medium is 10x and High is 40x) Diagram
Stage Clips These 2 stage clips hold the slide/specimen in place on the stage. Diagram
Diaphragm The Diaphragm controls the amount of light on the slide/specimen Turn to let more light in or to make dimmer. Diagram
Light Source Projects light upwards through the diaphragm, the specimen and the lenses Diagram
Ocular Lens/Eyepiece Magnifies the specimen image Has a magnification of 10x Diagram
Arm Used to support the microscope when carried. Holds the body tube, nose piece and objective lenses Diagram
Stage Supports the slide/specimen Diagram
Coarse Adjustment Knob Large knob that moves the stage up and down (visibly) for focusing your image Diagram
Fine Adjustment Knob smaller knob moves the stage SLIGHTLY to sharpen the image Diagram
Base Supports the microscope Diagram
Magnification
Magnification To determine your total magnification …you just multiply the ocular lens by the objective lens Ocular 10 x Objective 40 = So the object is 400 times “larger” Objective Lens have their magnification written on them. Ocular lenses usually magnifies by 10x
Caring for a Microscope Clean only with a soft cloth/tissue or lens paper Make sure it’s on a flat surface Don’t hit it against anything or anyone Carry it with 2 HANDS…one on the arm and the other under the base
Using a Microscope First KNOW WHAT YOU SHOULD BE LOOKING AT or FOR!!! Start on the lowest magnification (Low Objective) Place slide on stage and lock clips Adjust the COARSE knob first! Adjust light source if necessary Use fine adjustment to focus or sharpen the image
Using a Microscope DO NOT use the coarse adjustment knob on high magnification…you’ll break the slide!!! Only use the FINE ADJUSTMENT knob on High power When in doubt, and you can’t seem to focus on Medium or High, ALWAYS go back to LOW power
References http://www.cerebromente.org.br/n17/history/neurons1_i.htm Google Images http://science.howstuffworks.com/light-microscope1.htm