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US4845346A Expired / Lapsed US ⏱️ 0.0 years remaining

Touch panel having parallax compensation and intermediate coordinate determination

Assignee: Alps Alpine Co Ltd
•
Filing: 1988-03-25
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Granted: 1989-07-04
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Expires: 2008-03-25
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Abstract

Abstract Disclosed is here a coordinate input apparatus in which light sources and light receiving elements opposing thereto with an input operation space therebetween are arranged in an X-axis direction and in an Y-axis direction. The light sources and said light receiving elements form a plurality of pairs and the light sources are sequentially driven to accomplish a scan operation. Coordinates corresponding to the light receiving element of which a light path is interrupted by a coordinate input scan in the input operation space are outputtted as detection signals and as coordinate input data of a position where the light path is interrupted. The apparatus includes a double-precision coordinate calculate unit for calculating, when light paths of two adjacent light receiving elements are simultaneously interrupted, coordinates of an intermediate point associated with coordinates corresponding to the two light receiving elements and a coordiante value correcting unit for achieving a parallax correction on the coordinates calculated by the double-precision calculate unit by use of a correction table. As an output from the coordinate correcting unit is converted into be coordinates corresponding to the arrangement constituted with the light sources and the light receiving elements so as to be outputted as coordinate input data.

Inventors

  • 👤 Junichi Ouchi
  • 👤 Hiroaki Sasaki
  • 👤 Kazuo Hasagawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 10:44
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/0416; G06F3/0418; G06F3/042; G06F3/0421

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 193 words
A coordinate input apparatus in which light sources and light receiving elements opposing thereto with an input operation space therebetween are arranged in an X-axis direction and in an Y-axis direction, said light sources and said light receiving elements forming a plurality of pairs, said light sources are sequentially driven to accomplish a scan operation, coordinates corresponding to said light receiving element of which a light path is interrupted by a coordinate input scan in said input operation space are outputted as detection signals and as coordinate input data of a position where the light path is interrupted comprising: double-precision coordinate calculate means for calculating, when light paths of two adjacent light receiving elements are simultaneously interrupted, coordinates of an intermediate point associated with coordinates corresponding to said two light receiving elements and coordinate value correct means for achieving a parallax correction on the coordinates calculated by said double-precision calculate means by use of a correction table wherein an output from said coordinate correct means is restored to be coordinates corresponding to said arrangement constituted with the light sources and said light receiving elements so as to be outputted as coordinate input data.
Claim 2
Dependent Claim 193 words
A coordinate input apparatus in which light sources and light receiving elements opposing thereto with an input operation space therebetween are arranged in an X-axis direction and in an Y-axis direction, said light sources and said light receiving elements forming a plurality of pairs, said light sources are sequentially driven to accomplish a scan operation, coordinates corresponding to said light receiving element of which a light path is interrupted by a coordinate input scan in said input operation space are outputted as detection signals and as coordinate input data of a position where the light path is interrupted comprising: double-precision coordinate calculate means for calculating, when light paths of two adjacent light receiving elements are simultaneously interrupted, coordinates of an intermediate point associated with coordinates corresponding to said two light receiving elements and coordinate value correct means for achieving a parallax correction on the coordinates calculated by said double-precision calculate means by use of a correction table wherein an output from said coordinate correct means is restored to be coordinates corresponding to said arrangement constituted with the light sources and said light receiving elements so as to be outputted as coordinate input data.
Claim 3
Dependent Claim 16 words
A coordinate input apparatus according to claim 1 wherein each said light sources is a photoemitter.
Claim 4
Dependent Claim 17 words
A coordinate input apparatus according to claim 1 wherein each said light receiving elements is a photosensor.
Claim 5
Dependent Claim 32 words
A coordinate input apparatus according to claim 1 wherein said duble-precision coordinate calculate means includes change-over switch means, detection start coordinate memory means, continuous counter circuit means, multiplier means, and adder means.
Claim 6
Dependent Claim 33 words
A coordinate input apparatus according to claim 1 wherein said coordinate value correct means includes correction area position memory means, detection position comparator means, correction data memory means, adder means, and divider means.

References Cited (Backward Citations)

US4766424A Cited
US4672195A Cited
US4692609A Cited
US4766425A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-07-03 1993-01-02 1993-07-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-07-03 1997-01-02 1997-07-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-07-03 2001-01-02 2001-07-04 $7700.00 Window Closed / Lapsed

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