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ERIC Number: EJ851816
Record Type: Journal
Publication Date: 2009-Sep
Pages: 9
Abstractor: As Provided
Reference Count: 2
ISSN: ISSN-0143-0807
Focusing Light Rays Back to the Vertex of a Reflecting Parabolic Collector: The Equivalent of Dionysius Ear Effect in Optical Systems
De Luca, R.; Fedullo, A.
European Journal of Physics, v30 n5 p935-943 Sep 2009
A vertical light ray coming from infinity is reflected by a primary parabolic mirror M[subscript 1] having focus at F[subscript 1]. At a small distance from F[subscript 1] a secondary mirror M[subscript 2], symmetric with respect to the vertical axis, is placed. One would like to find the analytic equation of the mirror M[subscript 2], so that all rays from infinity, incident on M[subscript 1], could be sent back to the vertex V[subscript 1] of the primary mirror M[subscript 1]. We denote the mirror M[subscript 2] with the name of "zozzaroid", after P Zozzaro, who first proposed the problem. Recalling the famous legend about Dionysius ear, we find that M[subscript 2] has either an elliptic or a hyperbolic profile. (Contains 6 figures.)
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A