Abstract: A distance-measuring apparatus is formed of a photographic device formed of a pair of image-forming lenses and photosensor arrays for taking images of an object through the image-forming lenses, and a calculating device electrically connected to the photosensor arrays for calculating a distance to an object to be measured by two images of the object taken by the photographic device based on a triangulation principle.

Abstract: In a distance detection method, a pair of image data representing a pattern of images is obtained by using a pair of image sensors for receiving optical images. Then, a detection target extracted from each of the image data is captured while sequentially shifting positions of divisions in respective groups of divisions from window part data corresponding to a visual field to provide combinations, each having a pair of divisions, and a correlation value is calculated between each pair of the divisions. Also, a precision at a best correlation point as an indicator of reliability of the best correlation is obtained based on a changing condition of the correlation value near a shift value where the best correlation value has been calculated. Finally, a distance to the detection target is obtained by determining that the detection target is present in the visual field seen through the window corresponding to the window part data only when the precision exceeds a predetermined level.

Abstract: A distance-measuring apparatus includes light-sensitive devices formed of optical sensor arrays disposed on image-forming surfaces of right and left image-forming lenses, respectively. The apparatus uses image data from the optical sensor arrays of the light-sensitive devices to determine the distance from an object such as a vehicle in front of the apparatus via a distance detection circuit and capable of detecting condensation or a foreign particle obscuring a cover glass or defective pixels in the optical sensor arrays. In a defective condition, a defective visibility sensor emits an alarm signal to alert the operator.

Abstract: A method of the invention corrects a detection error, caused by an assembly error, in a distance or a distance-related index detected from an image captured in the visual field of an image detection module including an optical device and a pair of image sensing devices, each including a plurality of image sensors.

Abstract: An inter-vehicle distance to a preceding or following vehicle is reliably determined by using a simple processing, to alert the following vehicle to approach a dangerous range. The distance measurement apparatus includes a pair of light-receiving devices disposed on image-forming surfaces of lenses and having sensor lines and measurement windows on each sensor line at a certain interval, a distance detection device, a white line detection device and a vehicle detection device. The distance detection device detects distances at points, the coordinates of which are specified by the sensor line numbers and measurement window addresses. By using the detection results, the white line detection device detects a sensor line in which a white line on a road surface is present.