Distance measuring device for measuring the distance between vehicles

• US 5,253,050 A
• Filed: 03/03/1992
• Issued: 10/12/1993
• Est. Priority Date: 03/20/1991
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Karasudani, Keiko
• Primary Examiner(s): Chin, Tommy
• Assistant Examiner(s): LEE, RICHARD J
• Application Number:
  US07/845,269
• Time in Patent Office: 588 Days
• Field of Search: 358/103, 358/105, 358/107, 358/125, 358/126
• US Class Current: 348/118
• CPC Class Codes: B60R 1/00 Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
• CPC Class Codes: B60R 2300/105 using multiple cameras
• CPC Class Codes: B60R 2300/107 using stereoscopic cameras
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves

Abstract

A distance measuring device including an optical system for measuring a distance by trigonometric measurement, a display device for displaying an object, image following device for following an image of the object by a following window, first and second distance detecting device for calculating distances from the optical system to objects of which the images are present in the following window and the subwindow located adjacent thereto, image-following-condition detecting device for detecting a condition of following an image of the object by the following window, and window-setting renewal device for renewing the settings of all the subwindows on the basis of the data of the calculated distance and the detected image-following-condition.

Claims

1. A distance detecting device for measuring a distance from a follow object by trigonometrical measurement, by use of a pair of image signals representing a pair of object images of said follow object on image sensors through respective optical systems having parallel optical axes, said distance detecting device comprising:

display means for displaying said object image based on an object image signal picked up by one of said image sensors;

following means for setting a following window in a part including said object image on said display means so as to continuously follow said object image by said following window, at least one subwindow being adjacent to said following window and including another object image on said display means;

first distance detecting means for detecting a deviation between an image signal of said follow object from another one of said image sensors and said object image signal provided in said following window thus set as a reference, so as to calculate a distance to said follow object from said optical systems by said trigonometrical measurement;

second distance detecting means for detecting a deviation between an image signal of another object from said another image sensor and an another object image signal provided in each subwindow thus set as a reference, so as to calculate each distance to said another object included in said each subwindow from said optical systems by said trigonometrical measurement;

image-following-condition detecting means for detecting a condition following said object image in said following window, on the basis of the image signal data within said following window; and

window-setting renewal means for calculating a change of the movement of said follow object on the basis of the image-following-condition detecting means and the distance data from said first and second distance detecting means, to determine whether or not to renew the position of said following window and subwindow to follow said another object on said display means according to the calculated change.

2. A distance detecting device according to claim 1, wherein said optical systems are positioned in vertical direction.

3. A distance detecting device according to claim 1, wherein said optical systems are positioned in horizontal direction.

4. A distance detecting device according to claim 1, wherein said image-following-condition detecting means detects a symmetry of said object image within said following window, when said object is provided with a symmetric form.

5. A distance detecting method for measuring a distance from a follow object by trigonometrical measurement, by use of a pair of object image signals representing a pair of object images of said follow object on image sensors through respective optical systems having parallel optical axes, said distance detecting method comprising the steps of:

setting a following window on a display means in a part including said object image picked up by one of said image sensors so as to continuously follow said object image by said following window;

setting at least one subwindow adjacent to said following window on said display means, in which said subwindow includes another object image picked up by said one image sensor picking up said object image;

detecting a deviation between an image signal of said object image picked up by another one of said sensors and an object image signal provided in said following window thus set as a reference so as to calculate a distance to said follow object from said optical systems by said trigonometrical measurement;

detecting a deviation between an image signal of another object image picked up by said another one of said sensors and another object image signal provided in each subwindow thus set as a reference so as to calculate each distance to another object from said optical systems by said trigonometrical measurement;

detecting a condition following said object image in aid following window, on the basis of the image signal data within said following window; and

renewing the position of said following window and subwindow on said display means by a decision changing the follow object to said another object, on the basis of the detected image-following-condition data and the detected distance data of said follow object and said another object.