Distance measuring device
AssigneeAsahi Kogaku Kogyo Kabushiki Kaisha
InventorKimiaki Ogawa
Life of this patent
Estimating the term…
Abstract
A distance measuring device has an infrared light-emitting diode by which an infrared light is emitted towards a subject, and first and second linear line sensors on which an image corresponding to light reflected from the subject is formed. The first and second linear line sensors are disposed adjacently and in parallel to each other, and offset by an amount corresponding to half of the predetermined A/D converting step. Analog distance data outputted from the linear line sensors are converted to digital distance data using the predetermined A/D converting step, and then, the digital distance data are added together to obtain a subject distance with a high accuracy.
Claims20
A device for measuring a subject distance between an optical apparatus and a subject, said device comprising:
- means for emitting a beam of light towards said subject;
- a plurality of line sensors arranged parallel to one another and offset from each other in a longitudinal direction by a predetermined amount, said plurality of line sensors receiving light reflected from said subject and for sensing a position at which an image of said reflected light is formed;
- means for obtaining a subject distance data based on said position and to output said subject distance data as analog distance data;
- means for converting said analog distance data to digital distance data with a predetermined converting step;
- and
- means for processing said digital distance data to obtain said subject distance with a resolution higher than a resolution of said predetermined converting step.
A device for measuring a subject distance between an optical apparatus and a subject, said device comprising:
- means for emitting a beam of light towards said subject;
- a single line sensor that receives light reflected from said subject, said single line sensor sending a position at which an image of said reflected light is formed;
- means for obtaining subject distance data based on said position and for outputting said subject distance data as analog distance data;
- means for converting said analog distance data to a plurality of digital distance data with a predetermined converting step;
- and
- means for processing said digital distance data to obtain said subject distance with a resolution higher than said predetermined converting step, wherein said plurality of said digital distance data is offset by a fractional amount of said predetermined converting step.
A device for measuring a subject distance between an optical apparatus and a subject, said device comprising:
- a plurality of line sensors that receive light from said subject and outputs signals related to said subject distance, said plurality of line sensors being positioned parallel to one another and offset from each other in a first direction by an amount equal to a fraction of a predetermined converting step;
- at least one distance calculating circuit that calculates analog distance data based on said signals output by said plurality of line sensors;
- at least one A/D converter that converts said analog distance data to digital distance data with said predetermined converting step;
- and
- a processing circuit that processes said digital distance data to obtain said subject distance with a resolution higher than a resolution of said predetermined converting step.
A device for measuring a subject distance between an optical apparatus and a subject, said device comprising:
- a single line sensor that receives light from said subject and outputs signals related to said subject distance;
- a distance calculating circuit that calculates analog distance data based on said signals output by said single line sensor;
- at least one A/D converter that converts said analog distance data to digital distance data with a predetermined converting step;
- and
- a processing circuit that combines a plurality of said digital distance data, said plurality of said digital distance data being offset by a fractional amount of said predetermined converting step to obtain said subject distance with a resolution higher than a resolution of said predetermined converting step.
Dependencies are inferred from the claim text.