Patent ID: 8373128
Filing Date: 2013-02-12
Classification: G01S

Abstract:
1. An optical ranging sensor, comprising: an infrared light emitting device; a light receiving device placed at a distance from the infrared light emitting device, the light receiving device including a light receiving section, a signal processing section for processing a signal outputted from the light receiving section, an information memory section for storing information included in the signal from the light receiving section, and a signal processing software memory section for storing a software for processing the signal from the light receiving section; a first light-permeable resin section encapsulating the infrared light emitting device; a second light-permeable resin section encapsulating the light receiving device; a light-shielding resin member being in contact with the first light-permeable resin section and the second light-permeable resin section, the light-shielding resin member including a first window through which light from the infrared light emitting device passes and a second window through which light incident into the light receiving device passes; a drive circuit section for driving the infrared light emitting device; a light receiving device control section for controlling the light receiving device; and a control section for controlling the drive circuit section to intermittently drive the infrared light emitting device at predetermined intervals and for controlling the light receiving device control section to expose to light or operate the light receiving device in synchronization with a timing of driving the infrared light emitting device, wherein the control section configured to perform: a first control for continuously driving the infrared light emitting device in each of predetermined first periods and for controlling the light receiving device control section to continuously expose or operate the light receiving device in synchronization with a timing of continuously driving the infrared light emitting device; a second control for stopping the infrared light emitting device in each of predetermined second periods and for controlling the light receiving device control section to continuously expose or operate the light receiving device for a time generally identical to a time for which the infrared light emitting device is continuously driven in the first control; and measuring a distance based on a difference between a signal coming from the light receiving device during the first control and a signal coming from the light receiving device during the second control, and wherein the measured distance is between the infrared light emitting device and an object reflecting light emitted by the infrared light emitting device.