The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 22, 2002
Filed:
Jan. 23, 2001
John Graham Holden, Hemel Hempsted, GB;
Susan Styles, Hillingdon, GB;
Central Research Laboratories Limited, Hayes, GB;
Abstract
The apparatus comprises an object for display, a retro-reflector receiving light from the object, a beam-splitter in a path for light from the object to the retro-reflector, and a Fresnel lens (having no point of central symmetry) between the beam-splitter and the retro-reflector. The beam-splitter makes an oblique angle to the direction of propagation of the light, such that it transmits some light and reflects the rest. Light from the beam-splitter passes through the lens to the retro-reflector, which reflects it back through the lens to the beam-splitter. This retro-reflected light is reflected and/or transmitted by the beam-splitter to form a real image suspended in space. The type of Fresnel lens used in the apparatus improves viewability because unwanted reflections from the surfaces of the lens are shifted such that they are no longer visible when viewing the suspended image.