Close

Search

Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
SPECIAL ANNOUNCEMENT
2016 Photonics Buyers' Guide Clearance! – Use Coupon Code FC16 to save 60%!
Photonics Dictionary

overhead projector

A projector used to project transparencies. A horizontal 8 x 10-in. stage for writing or laying down preformed transparencies is provided with either an elliptical mirror or a plastic Fresnel lens below the stage to form an image of a lamp filament in the projection lens situated above the stage. A 45° mirror above or below the lens turns the vertical beam into a horizontal direction toward the screen behind the lecturer's head. The imagery is such that when the speaker is facing the audience, his normal writing on the stage appears erect and correct on the screen.
 
Terms & Conditions Privacy Policy About Us Contact Us
back to top

Facebook Twitter Instagram LinkedIn YouTube RSS
©2016 Photonics Media
x We deliver – right to your inbox. Subscribe FREE to our newsletters.