Focal point

Description

In an optical system, the focal point is the position at which the rays converge into a single point of focus. After passing through this image plane the rays diverge.

Synonyms and Related Terms

Brennpunkt (Deut.); foyer (Fr.); point focal (Fr.);

Authority

• ASTM, ASTM, Standard Terminology of Microscopy, Annual Book of ASTM Standards, Section 14, General Methods and Instrumentation, ASTM, E175, 75-78, May 1982

• Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976

• Random House, Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998