Obstacle detecting system for a motor vehicle

An obstacle detecting system for a motor vehicle, comprising:

• (a) a laser radar type distance detecting unit for detecting a distance to an object existing in a path of said motor vehicle as viewed in a first direction in which said motor vehicle is running,
• said distance detecting unit including:
• (i) laser beam sending means (10) for sending out a laser beam while deflecting said laser beam in a second direction laterally transverse to said first direction;
• (ii) echo light beam receiving means (11) for receiving an echo light beam resulting from reflection of said laser beam by said object;
• and
• (iii) distance calculating means (12) for arithmetically determining a distance to said object on the basis of a temporal period intervening between the send-out of said laser beam and the reception of said echo light beam;
• (b) an optical imaging unit including:
• (i) optical imaging means (20, 21) for picking up an image of an object located within a range swept by said laser beam;
• (ii) window setting means (4) for presetting a plurality of windows at predetermined locations on an imaging plane of said optical imaging unit;
• and
• (iii) distance detecting means (23) for detecting a distance to an object caught by said optical imaging unit at least within one of said windows;
• and
• (c) object size determining means (3) for selecting a window corresponding to a distance value which is detected by said optical imaging unit and which coincides with a distance value calculated by said laser radar type distance detecting unit, to thereby determine a size of said object on the basis of the preset position of said selected window.