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US5999307A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for controllable frustration of total internal reflection

Assignee: Concord HK International Education Ltd
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Filing: 1997-09-04
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Granted: 1999-12-07
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Expires: 2017-09-04
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Abstract

Abstract A method and apparatus for facilitating controllable switching an interface between a reflective state in which light incident upon the interface undergoes total internal reflection, and a non-reflective state in which total internal reflection is prevented at the interface. The apparatus incorporates a member (preferably an elastomer) which is deformable with respect to the interface. The member's Young's Modulus in portions of the member adjacent the interface is substantially greater (i.e. stiffer) than the member's Young's Modulus in portions of the member away from the interface. The stiffened portion of the member adjacent the interface may be in the form of a microstructure. A pair of electrodes coupled to a voltage source can be provided to controllably deform the member into optical contact with the interface, within a continuously variable range of optical contact values, to produce the non-reflective state in selectably varying degrees.

Inventors

  • 👤 Lorne A. Whitehead
  • 👤 J. Thomas Tiedje
  • 👤 Robin John Noel Coope

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 07:49
CPC Classifications
B; B29; B29C; B29C59/00; B29C59/16; G; G02; G02B; G02B26/00; G02B26/02; G02B6/00; G02B6/24; G02B6/255; B29C35/00; B29C35/02; B29C35/08; B29C35/0805; B29C2035/0827; B29K; B29K2021/00; G02B6/10; G02B6/12; G02B2006/12035; G02B2006/12069; G02B2006/12071

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 125 words
Apparatus for controllably switching an interface between a reflective state in which light incident upon said interface undergoes total internal reflection and a non-reflective state in which said total internal reflection is prevented at said interface, said apparatus comprising a member deformable with respect to said interface, said member's Young's Modulus in portions of said member adjacent said interface being substantially greater than said member's Young's Modulus in portions of said member away from said interface, wherein E>a/d, where E is said member's Young's Modulus at portions of said member adjacent said interface, a is the bond energy per unit area due to the Van der Waals force between said interface and said member, and d is a dimension characteristic of roughness of said interface.
Claim 2
Dependent Claim 125 words
Apparatus for controllably switching an interface between a reflective state in which light incident upon said interface undergoes total internal reflection and a non-reflective state in which said total internal reflection is prevented at said interface, said apparatus comprising a member deformable with respect to said interface, said member's Young's Modulus in portions of said member adjacent said interface being substantially greater than said member's Young's Modulus in portions of said member away from said interface, wherein E>a/d, where E is said member's Young's Modulus at portions of said member adjacent said interface, a is the bond energy per unit area due to the Van der Waals force between said interface and said member, and d is a dimension characteristic of roughness of said interface.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-12-06 2003-06-07 2003-12-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-12-06 2007-06-07 2007-12-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-12-06 2011-06-07 2011-12-07 $7700.00 Window Closed / Lapsed

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