The Schlieren Optics and how it works -Harvard

Very fascinating as this allows one to see invisible sounds waves, gases and much more. A point source of light is reflected from a concave mirror and focused onto the edge of a razor blade, which is mounted in front of the camera. Light refracted near the mirror and intercepted by the blade gives the illusion of a shadow.

Seen here are the heated gases from a candle flame and a hair dryer, helium gas, and sulfur hexafluoride gas.

For more information on our setup please see
http://sciencedemonstrations.fas.harv...

Note that this version of the setup uses a white LED flashlight instead of an automotive light bulb.

Disclaimer: All works The Truth Sayer Channel are criticism, comment, news reporting, teaching and research.
-All footage taken falls under ''fair use'' of the Digital Millennium Copyright Act (1998). Therefore, no breach of privacy or copyright has been committed.
-FAIR USE STATEMENT
This video may contain copyrighted material the use of which has not been specifically authorized by the copyright owner. This material is being made available within this transformative or derivative work for the purpose of education, commentary and criticism, is being distributed without profit, and is believed to be "fair use" in accordance with Title 17 U.S.C. Section 107