US 6,441,362 B1 · Stylus for optical digitizer

Abstract

An optical digitizer is constructed for determining a position of a pointing object projecting a light and being disposed on a coordinate plane. In the optical digitizer, a detector is disposed on a periphery of the coordinate plane and has a view field covering the coordinate plane for receiving the light projected from the pointing object and for converting the received light into an electric signal. A processor is provided for processing the electric signal fed from the detector to compute coordinates representing the position of the pointing object. A collimator is disposed to limit the view field of the detector below a predetermined height relative to the coordinate plane such that through the limited view field the detector can receive only a parallel component of the light which is projected from the pointing object substantially in parallel to the coordinate plane. A shield is disposed to enclose the periphery of the coordinate plane to block a noise light other than the projected light from entering into the limited view field of the detector.

Claims10

Dependent claims

An optical stylus having a point light movable along a coordinate plane according to a drawing operation and being used as an input device for an optical digitizer which converts the point light into an electric signal to compute coordinates of a position of the point light, the optical stylus comprising:

a holder portion that may be manually manipulated to perform the drawing operation;
a tip portion protruding from the holder portion and forming the point light, the tip portion comprising a plurality of light-emitting members each for emitting light of a different color and a light guide member for encapsulating the light-emitting members, the light guide member comprising a transparent material having a tubular configuration having a closed tip end, an open end, an outer face and an inner face, the light-emitting members being mounted in the open end, and at least one of the outer face and the inner face being patterned to scatter the light emitted from the light-emitting members;
and
writing force detecting means for detecting a writing force applied to the tip portion and controlling the respective light-emitting members to emit light depending upon the detected writing force.

1 more element

Dependencies are inferred from the claim text.

Stylus for optical digitizer

Life of this patent

Stylus for optical digitizer

Life of this patent

Abstract

Claims10