Distance measuring system

A distance measuring system, comprising:

• a light emitting device for emitting light to a plurality of range finding areas;
• a light receiving device having a plurality of receiving portions corresponding to said plurality of range finding areas, each of said plurality of receiving portions being positioned to receive light of said light emitting device which has been reflected from an object in a range finding area which corresponds to the respective receiving portion and outputting signals with respect to a distance of an object every time said light emitting device emits light;
• a controller for controlling said light emitting device to emit light at least one time to all of the range finding areas and a larger number of times to a specified one of said range finding areas;
• and
• a distance detector for measuring a distance of an object based on a plurality of signals outputted from said light receiving device.

A distance measuring system comprising:

• a light emitting device which emits a first emission of light at a first time and a second emission of light at a second time to a predetermined range finding area for a range-finding operation;
• a light receiving device which receives light of said light emitting device which has been reflected from an object in said predetermined range finding area, said light receiving device including first, second, and third light receiving areas arranged in a line along a base length, the first and second light receiving areas comprising a first light receiving portion for receiving light of said light emitting device which has been reflected from an object in a first distance range of said predetermined range finding area, and the second and third light receiving areas comprising a second light receiving portion for receiving light of said light emitting device which has been reflected from an object in a second distance range of said predetermined range finding area, said second distance range being different from said first distance range, wherein said second light receiving area of said light receiving device is common to and is included in each of said first and second light receiving portions;
• a range finding device which calculates an object distance on the basis of an output of either one of said first light receiving portion or said second light receiving portion so that another object distance can be measured for said predetermined range finding area;
• a switch for instructing a start of the range-finding operation;
• and
• a controller which controls, in response to an instruction from said switch, said light emitting device to emit said first emission of light at said first time and said second emission of light at said second time to said predetermined range finding areas, and which controls said range finding device to calculate object distance on the basis of the output of said first receiving portion when said light emitting device emits light at said first time and to calculate the object distance on the basis of the output of said second receiving portion when said light emitting device emits light at said second time to obtain an acceptable ratio of the outputs of said first and second receiving portions.

A distance measuring system, comprising:

• a first distance detector for measuring a distance of an object within a plurality of range finding areas encompassing a field of view;
• a second distance detector for measuring a distance of an object at a distance, within the field of view, which is different from the distance measured by the first distance detector;
• and
• judging means for automatically judging whether or not an object distance within the field of view can be correctly measured on the basis of a distance measurement by the first distance detector without a distance measurement by the second distance detector,
• wherein, if it is judged that the object distance can be correctly measured without a distance measurement by the second distance detector, the second distance detector is not operated, and if it is judged that the object distance cannot be correctly measured without a distance measurement by the second distance detector, the second distance detector is operated by selecting corresponding sets, each set comprising a light emitting device and a light receiving device, to achieve an acceptable ratio of outputs of the thus selected light receiving devices.

A distance measuring system having a plurality of distance measurement areas in a field of view, said system comprising:

• a first distance detector for measuring a distance of an object within a specific one of said plurality of distance measurement areas in said field of view, said specific one of said plurality of distance measurement areas having a first distance measurement range;
• a second distance detector for measuring a distance of an object within said plurality of distance measurement areas in said field of view, said plurality of distance measurement areas having a second distance measurement range, wherein said second range of distance measurement is different from said first range of distance measurement;
• and
• judging means for initially judging whether an object distance is detectable by said second distance detector through first operating the second distance detector so that the distance of the object is detected within the second distance measurement range,
• (a) if detectable by the second distance detector, concluding distance detection without operating the first distance detector, and
• (b) if not detectable by the second distance detector, automatically operating the first distance detector so that the distance of the object is detected within the first distance measurement range.

In a multi-area range finding system comprising:

• a first light emitting device which emits light comprising a first emission of light to a first range finding area of an object;
• a first light receiving device which receives light of said first light emitting device which has been reflected from said first range finding area;
• a first range finding device which calculates an object distance in said first range finding area on the basis of an output of said first light receiving device, which output is responsive to the first emission of light;
• a second light emitting device which emits light comprising a second emission of light to a second range finding area of the object;
• a second light receiving device which receives light of said second light emitting device which has been reflected by said second range finding area;
• a second range finding device which calculates another object distance in said second range finding area on the basis of an output of said second light receiving device, which output is responsive to said second emission of light;
• and
• the improvement further comprising a third range finding device which calculates the object distance in the first range finding area on the basis of the output of said second light receiving devices, which output is responsive to a third emission of light comprising another emission of light by said first light emitting device so that a distance which cannot be detected by said first range finding device can be detected to obtain an acceptable ratio of outputs from pairs of a selected light emitting device and a selected light receiving device, and
• wherein said first and second light receiving devices are arranged in a line along a base length and said first, second and third light emissions are achieved in that order.