Introduction to Microscopy:
• The Light Microscope
• The TEM
• The SEM
Introduction to Microscopy (Use of Microscopes to study minute [small] objects)
• The image to the right is a light microscopelight microscope
• Light microscopes bounce light waves off of an object. The light source may be from the sun or from a bulb from a lamp.
• The diaphragm of a light microscope controls the amount of light the enters the stage to illuminate the specimen being examined.
Resolution: The resolution of a microscope is a measure of the clarity the image produced by the scope; the smallest distance between
to points that can be seen as being separate.
• http://www.olympusmicro.com/primer/java/microscopy/airydiscs/index.html
• The image below shows the difference between the resolution of a light microscope versus an electron microscope
Electron Microscopes: these microscopes bounce a beam of electrons off of an object instead of light. These
microscopes have a high resolution (smaller distance between two points)
There are two types of electron microscopes:
• SEM (scanning electron microscope)– Produces a three-dimensional image)
• TEM (transmission electron microscope)– Produces a two-dimensional image)
SEM Images (Three-Dimensional)
http://micro.magnet.fsu.edu/primer/java/electronmicroscopy/magnify1/index.html
TEM images
Which has better resolution of image?
Controls amount of light entering the stage
http://images.google.com/imgres?imgurl=http://shs.westport.k12.ct.us/mjvl/biology/microscope/parts.gif&imgrefurl=http://shs.westport.k12.ct.us/mjvl/biology/microscope/microscope.htm&h=314&w=458&sz=5&hl=en&start=1&um=1&tbnid=BLEnDPCBo0ZxeM:&tbnh=88&tbnw=128&prev=/images%3Fq%3Dhow%2Bto%2Buse%2Ba%2Bmicroscope%26svnum%3D10%26um%3D1%26hl%3Den