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

http://www.mos.org/sln/sem/staple.gif

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