System with optical sensor for detecting user input

摘要

A light-based input device may be based on a wedge-shaped light-guide structure. Light may be introduced into the interior of the light-guide structure from a light source and corresponding reflected light exiting the light-guide structure may be measured using a light detector such as an image sensor. The location at which a user places an object in contact with an upper surface of the light-guide structure may be detected by analyzing the pattern of reflected light that exits the light-guide structure. Multiple layers of light-guide structures may be separated from each other by opaque material such as plastic so that the device can determine the direction in which the object is traversing the light-guide layers. A light-based input device may be implemented using free-space light beams that are interrupted by the user. Keys may be provided in a light-based input device by movably mounting contact pads to a light-guide structure.

主权项

1. An input device for gathering user input in an electronic device, comprising:
a light-guide structure; a light source that supplies light to the light-guide structure; an image sensor that detects contacts between an object that is manipulated by a user and the light-guide structure, wherein the light-guide structure comprises a wedge-shaped transparent member having an upper surface and an end face, wherein the image sensor measures reflected light patterns on the end face that result from contact between the object and the upper surface, wherein the image sensor is configured to detect different light patterns depending on which location along the upper surface is contacted by the object, wherein the light-guide structure comprises first and second light-guide structure layers that are separated by an opaque layer and wherein the image sensor is configured to determine from the measured reflected light patterns which of the first and second light-guide structure layers is being contacted by the object and is configured to determine a direction of movement of the object relative to the light-guide structure.