Distance detecting apparatus, air bag system controlling apparatus, and method of detecting distance

Abstract

A light emitting unit emits a light in a light emitting direction, which is the direction to an object, the light having a distributed pattern in a predetermined direction. A photographing device obtains an image of the object along with a photographing direction. A holding mechanism holds the light emitting unit and the photographing apparatus in such a relation that (a) the photographing direction is not in a plane that includes both the light emitting direction and the predetermined direction of the distributed pattern, and (b) the photographing direction is not parallel to the light emitting direction. A distance deriving unit derives a distance between the object and a predetermined position based on the image obtained by the photographing device.

1 . A distance detecting apparatus comprising: 
 a light emitting unit configured to emit a light in a light emitting direction, the light having a distributed pattern in a predetermined direction;    a photographing device configured to obtain an image of an object along with a photographing direction;    a holding mechanism configured to hold the light emitting unit and the photographing device in such a relation that 
 (a) the photographing direction is not in a plane that includes both the light emitting direction and the predetermined direction of the distributed pattern, and  
 (b) the photographing direction is not parallel to the light emitting direction; and  
   a distance deriving unit configured to derive a distance between the object and a predetermined position based on the image obtained by the photographing device.    
   
   
       2 . An air bag system controlling apparatus comprising: 
 a light emitting unit configured to emit a light in a light emitting direction, the light having a distributed pattern in a predetermined direction;    a photographing device configured to obtain an image of an object along with a photographing direction;    a holding mechanism configured to hold the light emitting unit and the photographing device in such a relation that 
 (a) the photographing direction is not in a plane that includes both the light emitting direction and the predetermined direction of the distributed pattern, and  
 (b) the photographing direction is not parallel to the light emitting direction;  
   a distance deriving unit configured to derive a distance between the object and a predetermined position based on the image obtained by the photographing device; and    an air bag system controlling unit configured to control an operation of an air bag based on the distance derived.    
   
   
       3 . The air bag system controlling apparatus according to  claim 2 , wherein the light emitting unit emits a infrared light, and 
 the photographing device obtains an infrared image.    
   
   
       4 . The air bag system controlling apparatus according to  claim 2 , wherein the light emitting unit emits the light when an operation of the air bag system controlling unit is required, and 
 the distance deriving unit derives the distance based on the image when the light emitting unit emits the light.    
   
   
       5 . The air bag system controlling apparatus according to  claim 2 , wherein the light emitting unit emits the light having a distributed pattern perpendicular to the light emitting direction.  
   
   
       6 . The air bag system controlling apparatus according to  claim 2 , wherein the light emitting unit emits the light having a discretely distributed pattern perpendicular to the light emitting direction.  
   
   
       7 . The air bag system controlling apparatus according to  claim 2 , wherein the distance deriving unit further comprises an identifying unit that identifies a position of the distributed pattern of the light in the image by comparing a first image that is an image when the light emitting unit emits the light and a second image that is an image when the light emitting unit does not emit the light.  
   
   
       8 . The air bag system controlling apparatus according to  claim 2 , wherein the distance deriving unit further comprises: 
 a dividing unit configured to divide the image into a plurality of regions; and    an identifying unit configured to identify a position of the distributed pattern of the light in the image by calculating an average of a high-luminance part in each of the regions.    
   
   
       9 . The air bag system controlling apparatus according to  claim 2 , wherein the light emitting unit emits the light from a front side of the seat.  
   
   
       10 . The air bag system controlling apparatus according to  claim 2 , wherein the distance deriving unit stores a relation between positions of the distributed pattern of the light in the image and distances, and derives the distance by referring to the relation stored.  
   
   
       11 . The air bag system controlling apparatus according to  claim 2 , wherein the distance deriving unit derives the distance based on a position of the distributed pattern of the light in the image, by extracting a high-luminance part in the image, and identifying whether the high-luminance part corresponds to the position of the distributed pattern of the light in the image.  
   
   
       12 . An air bag system controlling apparatus comprising: 
 a light emitting unit configured to emit a light in a light emitting direction which is the direction to an object the light having a distributed pattern in a predetermined direction;    a photographing device configured to obtain an image of an object along with a photographing direction;    a holding mechanism configured to hold the light emitting unit and the photographing device, in such a relation that 
 (a) the photographing direction is not in a plane that includes both the light emitting direction and the predetermined direction of the distributed pattern, and  
 (b) the photographing direction is not parallel to the light emitting direction;  
   a memory unit configured to store a computer program that executes a function of deriving a distance between the object and a predetermined position based on the image obtained by the photographing device and executes a function of controlling an operation of an air bag based on the distance derived; and    a computer processor configured to access the memory unit and execute the computer program stored in the computer readable memory unit.    
   
   
       13 . A method of detecting a distance, comprising: 
 emitting light in a light emitting direction to thereby irradiate an object, the light being having a distributed pattern in a predetermined direction;    obtaining an image of the object along with a photographing direction, in such a manner that 
 (a) the photographing direction is not in a plane that includes both the light emitting direction and the predetermined direction of the distributed pattern and  
 (b) the photographing direction is not parallel to the light emitting direction; and  
   deriving a distance between the object and a predetermined position based on a position of the pattern light in the image.