Patent ID: 7123351

Claim:
A distance measuring system for measuring a distance between a reference point and a point of interest, comprising: a distance measuring device having a straight reference line extending forward of the device and a reference point located on the reference line; the device having light source means for emitting light to be reflected from points forward of the device and the reference point that are located on or substantially on the reference line; the device having light detector means for detecting intensities of light emitted by the light source means and reflected to the light detector means from points forward of the device and the point of reference that are located on or substantially on the reference line and for generating electronic signals related to the detected intensities; at least the light source means comprising multiple light sources that are each fixed relative to the reference point with the light sources being offset from each other in a direction perpendicular to the reference line and at least one of the light sources being located a fixed perpendicular offset distance from the reference line or the light detector means comprising multiple light detectors that are each fixed relative to the reference point with the light detectors being offset from each other in a direction perpendicular to the reference line and at least one of the light detectors being located a fixed perpendicular offset distance from the reference line so that intensities of light emitted by the light source means, reflected from any of the points forward of the device that are located on or substantially on the reference line, and detected by the light detector means generates electronic signals that can be used to determine a distance between the reference point and a point on a surface of an object that is located forward of the device on or substantially on the reference line; and electronic means for receiving the electronic signals generated by the light detector means and for computing, utilizing light intensity emitting patterns of the light sources and locations of the light sources relative to the reference line or light intensity detecting sensitivity patterns of the light detectors and locations of the light detectors relative to the reference line, a distance from the reference point to a point on a surface of an object located on or substantially on the reference line.