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US4561017A Expired / Lapsed US ⏱️ 0.0 years remaining

Graphic input apparatus

Assignee: Individual
•
Filing: 1983-08-19
•
Granted: 1985-12-24
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Expires: 2003-08-19
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Abstract

Abstract A computer graphic input device is disclosed for imaging the points of contact between objects and a surface. The input device is defined by a transparent material with one surface thereof defining a drawing surface. The index of refraction of the material is greater than the index of refraction of the medium on the upper side of the drawing surface. In the preferred embodiment, the transparent material is prism shaped in configuration. A camera is mounted on the lower side of the drawing surface in a manner to only capture light rays which have been totally internally reflected from the drawing surface. By this arrangement, objects located on the upper side of the drawing surface will be imaged by the camera only when and where the object is in direct contact with the drawing surface. The size and shape of the input pattern is digitized, processed and displayed on a monitor. The subject apparatus can be used to produce graphic effects achieved by various natural drawing implements, such as a brush.

Inventors

  • 👤 Richard Greene

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 23:17
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/042; G06F3/0425; G06F3/048; G06F3/0484; G06F3/04845; G06F2203/00; G06F2203/041; G06F2203/04109

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 134 words
A graphical input device comprising: a transparent material with one surface thereof defining a drawing surface, with the index of refraction of the material being greater than the index of refraction of the medium on one side of the drawing surface; light absorbing means located on the other side of said drawing surface; camera means located on said other side of said drawing surface and in a manner to only capture light rays which originate from said light absorbing means and which have been totally internally reflected from said drawing surface whereby lighted objects placed on said drawing surface will be imaged by said cameral means only when said objects are in direct contact with said one side of said drawing surface, with the remaining field being dark due to said light absorbing means.
Claim 2
Dependent Claim 134 words
A graphical input device comprising: a transparent material with one surface thereof defining a drawing surface, with the index of refraction of the material being greater than the index of refraction of the medium on one side of the drawing surface; light absorbing means located on the other side of said drawing surface; camera means located on said other side of said drawing surface and in a manner to only capture light rays which originate from said light absorbing means and which have been totally internally reflected from said drawing surface whereby lighted objects placed on said drawing surface will be imaged by said cameral means only when said objects are in direct contact with said one side of said drawing surface, with the remaining field being dark due to said light absorbing means.
Claim 3
Dependent Claim 48 words
A graphical input device as recited in claim 1 further including a liquid layer covering said drawing surface, said liquid having an index of refraction greater than the surrounding medium such that said liquid layer functions to define an effective drawing surface to facilitate the imaging of objects.
Claim 4
Dependent Claim 51 words
A graphical input device as recited in claim 1 wherein said transparent material has at least three faced, with a first face defining the drawing surface, and wherein a darkened second face defines said light absorbing means and wherein said camera means is located to receive light through a third face.
Claim 5
Dependent Claim 36 words
A graphical input device as recited in claim 3 further including a means for illuminating objects to be imaged, said illumination means being directed into the transparent material through a face other than said third face.
Claim 6
Dependent Claim 22 words
A graphical input device as recited in claim 1 further including a means for correcting horizontal distortion created by said camera means.
Claim 7
Dependent Claim 39 words
A graphical input device as recited in claim 5 wherein said correcting means is defined by a means for modulating the horizontal deflection of the scanning beam of said camera means in proportion to the degree of vertical deflection.
Claim 8
Dependent Claim 143 words
A graphical input device comprising: a transparent material having at least four faces and a prismatic configuration, with a first face defining a drawing surface and a second face being parallel to the first, with the index of refraction of the material being greater than the index of refraction of the medium on one side of the drawing surface; camera means located in a manner to only capture light rays which have been totally internally reflected from said drawing surface such that an object will be imaged only when said object is in contact with said one side of the drawing surface; and a video monitor for displaying images captured by said camera means, said monitor being located adjacent said second surface to permit the viewing of objects imaged by said camera means and displayed by said video monitor through the drawing surface.
Claim 9
Dependent Claim 143 words
A graphical input device comprising: a transparent material having at least four faces and a prismatic configuration, with a first face defining a drawing surface and a second face being parallel to the first, with the index of refraction of the material being greater than the index of refraction of the medium on one side of the drawing surface; camera means located in a manner to only capture light rays which have been totally internally reflected from said drawing surface such that an object will be imaged only when said object is in contact with said one side of the drawing surface; and a video monitor for displaying images captured by said camera means, said monitor being located adjacent said second surface to permit the viewing of objects imaged by said camera means and displayed by said video monitor through the drawing surface.
Claim 10
Dependent Claim 48 words
A graphical input device as recited in claim 7 further including a liquid layer covering said drawing surface, said liquid having an index of refraction greater than the surrounding medium such that said liquid layer functions to define an effective drawing surface to facilitate the imaging of objects.
Claim 11
Dependent Claim 22 words
A graphical input device as recited in claim 7 wherein said video monitor displays imaged objects in white on a dark background.
Claim 12
Dependent Claim 22 words
A graphical input device as recited in claim 7 wherein said video monitor displays imaged objects in black on a light background.
Claim 13
Dependent Claim 22 words
A graphical input device as recited in claim 7 further including a means for correcting horizontal distortion created by said camera means.
Claim 14
Dependent Claim 39 words
A graphical input device as recited in claim 11 wherein said correcting means is defined by a means for modulating the horizontal deflection of the scanning beam of said camera means in proportion to the degree of vertical deflection.

References Cited (Backward Citations)

US3846826A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-12-23 1989-06-24 1989-12-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-12-23 1993-06-24 1993-12-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-12-23 1997-06-24 1997-12-24 $7700.00 Window Closed / Lapsed

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