Light-based touch screen using elongated light guides
First Claim
1. A method for detecting touch on a display, comprising:
- providing a display, a light pulse receiver, an elongated light guide below an edge of the display, the light guide including an elongated outer surface portion, an elongated scatterer strip inside the light guide, and an exit surface coupled to the light pulse receiver, and a reflective strip, separate from the light guide, mounted along the edge of the display above the light guide;
transmitting light pulses over the display and into the light guide through the elongated outer surface portion via the reflective strip;
scattering, by the scatterer strip, the light pulses inside the light guide, such that a portion of the scattered light pulses arrives at the exit surface; and
determining a location of an object touching the display that partially blocks the transmitted light pulses, based on outputs of the light pulse receiver.
0 Assignments
0 Petitions
Accused Products
Abstract
A touch screen including a housing, a display mounted in the housing, a plurality of collimating lenses mounted in the housing and arranged along a first edge of the display, a plurality of light pulse emitters mounted in the housing that are spaced apart from and serially transmit light pulses through the collimating lenses over the display, a light guide mounted in the housing along the edge of the display opposite the first edge, for receiving the light pulses, the light guide including a reflective strip that reflects light pulses to one end of the light guide, a light pulse receiver mounted in the housing near the one end of the light guide, for receiving the reflected light pulses, and a calculating unit, mounted in the housing and connected to the receiver, for determining a location of a pointer on the display that partially blocks light pulses transmitted by the emitters, based on outputs of the receiver.
116 Citations
9 Claims
-
1. A method for detecting touch on a display, comprising:
-
providing a display, a light pulse receiver, an elongated light guide below an edge of the display, the light guide including an elongated outer surface portion, an elongated scatterer strip inside the light guide, and an exit surface coupled to the light pulse receiver, and a reflective strip, separate from the light guide, mounted along the edge of the display above the light guide; transmitting light pulses over the display and into the light guide through the elongated outer surface portion via the reflective strip; scattering, by the scatterer strip, the light pulses inside the light guide, such that a portion of the scattered light pulses arrives at the exit surface; and determining a location of an object touching the display that partially blocks the transmitted light pulses, based on outputs of the light pulse receiver. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method for detecting touch on a display, comprising:
-
providing a display, an elongated light guide below an edge of the display, the light guide including an elongated outer surface portion, an elongated scatterer strip inside the light guide, two light pulse emitters coupled respectively to opposite ends of the elongated light guide, a reflective strip, separate from the light guide, mounted along the edge of the display above the light guide, and a plurality of light pulse receivers along an opposite edge of the display; providing two reference values for each receiver, corresponding respectively to light detections when each of the two light pulse emitters is separately activated and no object touches the display; separately activating each of the two light emitters to emit light pulses at one end of the light guide; for each activation; scattering, by the scatterer strip, the light pulses inside the light guide, such that the scattered light pulses exit through the entire elongated outer surface portion, cross over the display via the reflective strip, and arrive at the receivers, each receiver outputting a value corresponding to an actual amount of light detected; and for each receiver, comparing the output value to the reference value for that receiver corresponding to the activated emitter; and determining a location of an object touching the display that partially blocks the transmitted light pulses, based on the results of said comparing. - View Dependent Claims (8, 9)
-
Specification