Introduction to the Microscope Care Parts Focusing Students will have their microscopes out, for reference as we go through each of the steps. As an introduction, students will be asked what kinds of things they can do with this tool.
Microscope Care Always carry with 2 hands Only use lens paper for cleaning Do not force knobs Always store covered Keep objects clear of desk and cords Teacher demonstrates how to hold the microscope, where the lens paper is located and how to use it. Students will be invited to turn the knobs and observe the stage as it moves up and down. Teacher will demonstrate how to store the microscope.
Parts of a Compound Microscope
Microscope Parts Eyepiece Body Tube Revolving Nosepiece Arm Objective Lens Stage Stage Clips Coarse Focus This is the exact version of the microscope used in class. Students will be identifying the parts on the microscopes at their desks as we go along and what their functions are. Diaphragm Fine Focus Light Base
Compound Microscope A microscope is a very powerful magnifying glass A microscope helps you see things like cells up close
Eyepiece View the specimen through the eyepiece
Stage Clips & Objectives Stage clips hold the slide in place Low power objective is used to focus the microscope (short & fat) High power objective is used to view details of a specimen
Coarse Adjustment, Fine Adjustment, & Base Coarse adjustment focuses adjustment Fine adjustment fine tunes & gives detailed focus(usually smaller than coarse adjustment knob) Base is where the microscope rests
Stage Stage is part where the slide rests Mirror (or light source) directs light upwards onto the slide.
Diaphragm Diaphragm allows light in
Nosepiece Nosepiece is the rotating device that holds the objectives (lenses)
Arm Arm is the part where you carry the microscope
Can you name the parts of a compound microscope?
Answers base mirror (light source) diaphragm stage stage clips low power objective lens high power objective lens nosepiece arm fine focus knob body tube coarse focus knob eyepiece
Types of Microscopes
Light microscope (for small objects - similar to the way binoculars magnify objects far away.)
The Compound Light Microscope http://www.cas.muohio.edu/~mbi-ws/microscopes/compoundscope.html
May have many lenses that magnify the object Eyepiece = 10x magnification Objective = 10x (low) or 40X (high)
Total magnification= eyepiece X objective ex: 10x X 40x = 400x total magnification
Compound Light Microscope Powered by Light & Lenses Powers of Magnification Ocular Lens= _________ Low Power Objective= _______ Medium Power Objective= _______ High Power Objective= _______ Calculating Total Magnification= ____________ Resolution Parts
Stereomicroscope To look at large things that light cannot pass through (one eyepiece for each eye)
Stereomicroscopes http://scientificsonline.com/product.asp_Q_pn_E_3119600 http://www.martinmicroscope.com/MicroscopePages/Stereomicroscopes.htm
Stereomicroscopes 3 - D image can only magnify 10x to 600x
Electron Microscope can magnify more than 500,000x
House Fly http://www.pbrc.hawaii.edu/bemf/microangela/hfly.htm
Using the Microscope Place the Slide on the Microscope Use Stage Clips Click Nosepiece to the lowest (shortest) setting Look into the Eyepiece Use the Coarse Focus Give students a slide from the “common things” set, each student will practice focusing and changing objectives.
Using High Power Follow steps to focus using low power Click the nosepiece to the longest objective Do NOT use the Coarse Focusing Knob Use the Fine Focus Knob to bring the slide into focus Have students exchange slides so they can look at different things, walk them through using the high power objective to focus slides. Emphasize not using the coarse objective during this process, as it will crack the slides. What can you find on your slide?