Patent ID: 8797513
Filing Date: 2014-08-05
Classification: G01C,G01S

Abstract:
1. A distance measuring system comprising: an irradiation unit for emitting a pulsed light to a target object, wherein the pulsed light is reflected by the target object; a solid-state image sensing device for generating photoelectrons depending on the energy of the reflected light received in a light-receiving period predetermined for the emission timing of the pulsed light, and cumulatively storing therein the generated photoelectrons; and an arithmetic processing unit for determining a distance to the target object according to a time-of-flight process using information concerning the photoelectrons cumulatively stored in the solid-state image sensing device, wherein: the light-receiving period includes a first light-receiving period and a second light-receiving period; the solid-state image sensing device cumulatively stores therein photoelectrons generated depending on the energy of the light received in the first light-receiving period, and also cumulatively stores therein photoelectrons generated depending on the energy of the light received in the second light-receiving period; the first light-receiving period is a part of a rise period during which the intensity of the reflected light received by the solid-state image sensing device rises, and the second light-receiving period includes a peak point of the intensity of the reflected light received by the solid-state image sensing device and a fall period during which the intensity thereof falls; and the arithmetic processing unit determines the distance to the target object using a light energy ratio obtained by dividing information concerning the photoelectrons cumulatively stored in the second light-receiving period by information concerning the photoelectrons cumulatively stored in the first light-receiving period.