Discrete & Computational Geometry

, Volume 5, Issue 6, pp 529–531 | Cite as

Convex disks can cover their shadow

  • Géza Kós
  • Jenő Törőcsik


We give a short proof of the fact that given any two-dimensional convex disk in three-space and an orthogonal projectionC′ ofC on a plane then there is a congruent copy ofC which containsC′.


Orthogonal Projection Parallel Line Discrete Comput Geom Convex Compact Computational Geometry 
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Copyright information

© Springer-Verlag New York Inc. 1990

Authors and Affiliations

  • Géza Kós
    • 1
  • Jenő Törőcsik
    • 1
  1. 1.Department of MathematicsEötrös UniversityBudapestHungary

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