Patent ID: 7764358
Filing Date: 2010-07-27
Classification: G01C

Abstract:
1. A distance measuring system comprising: a light source configured to emit light; an image capture apparatus including a first lens module, a second lens module, and an image sensor, the first lens module and the second lens module being separated from each other a distance, the first lens module and the second lens module disposed between the light source and the image sensor, each of the first lens module and the second lens module defining a center axis, the first lens module having a first focus, the second lens module having a second focus, the image capture apparatus capable of detecting two light beams emitted from the light source and transmitting through the first lens module and the second lens module at two optical spots of the first lens module and the second lens module, respectively, the image capture apparatus also capable of measuring two distances between the two optical spots and nearest points of the center axes of the two lens modules, respectively, and measuring two angles defined between the two light beams and a line that passes through both a center of the first lens module and a center of the second lens module, respectively; a light absorption member disposed generally between the first lens module and the second lens module for absorbing light reflected from the lens modules and thereby reducing optical interference; and a signal processing circuit configured for calculating ratios of the two distances to two focal lengths represented by the two focuses, respectively, obtaining a value of each of the angles accordingly, and calculating a perpendicular distance from the light source to the line that passes through the first and second lens modules based on the angles and a length of the sensitive center portion of the image sensor between the two optical spots.