Distance measuring apparatus
First Claim
1. A distant measuring apparatus comprising:
- light-transmitting means for transmitting electromagnetic waves to scan in a specified scan direction a specified detection area which is partitioned into a plurality of standard areas of a fixed width;
light-receiving means for receiving reflection of said electromagnetic waves transmitted from said light-transmitting means and reflected by a target object in said detection area;
memory means for storing signals from said light-receiving means individually corresponding to said standard areas;
area-combining means for carrying out cumulative addition of the signals stored in said memory means corresponding to a set of those of said standard areas which are mutually adjacent in said scan direction to obtain a combined signal associated with a single combined area consisting of said set of standard areas if the signals corresponding to said set of standard areas do not exceed a threshold value, those of said standard areas, the signals from which are not cumulatively added, being each defined as a different one of combined areas and the signals therefrom being each defined as a different combined signal associated therewith; and
judging means for judging presence and position of a target object from the combined signals from the combined areas obtained by said area-combining means.
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Accused Products
Abstract
A distance measuring apparatus includes components for transmitting electromagnetic waves such as laser light to scan a detection area, and receiving reflected waves. The detection area is partitioned into standard areas of a fixed width and signals corresponding to waves received from different standard areas are stored separately. Mutually adjacent standard areas are combined to form a single combined area, if the corresponding signals each fail to exceed a specified threshold value, and these signals are cumulatively added. Conditions of a target object, such as its presence and its position, may be judged on the basis of combined areas thus created such that the detection can be made with increased sensitivity although the resolving power is adversely affected. An upper limit may be introduced for the number of standard areas over which cumulative addition of signals may be made. The threshold value may be made variable according to an average of signal values to be used for detection judgment or the noise component, or time-dependent so as to decrease as the delay time until the reflected waves are received increases.
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Citations
9 Claims
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1. A distant measuring apparatus comprising:
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light-transmitting means for transmitting electromagnetic waves to scan in a specified scan direction a specified detection area which is partitioned into a plurality of standard areas of a fixed width;
light-receiving means for receiving reflection of said electromagnetic waves transmitted from said light-transmitting means and reflected by a target object in said detection area;
memory means for storing signals from said light-receiving means individually corresponding to said standard areas;
area-combining means for carrying out cumulative addition of the signals stored in said memory means corresponding to a set of those of said standard areas which are mutually adjacent in said scan direction to obtain a combined signal associated with a single combined area consisting of said set of standard areas if the signals corresponding to said set of standard areas do not exceed a threshold value, those of said standard areas, the signals from which are not cumulatively added, being each defined as a different one of combined areas and the signals therefrom being each defined as a different combined signal associated therewith; and
judging means for judging presence and position of a target object from the combined signals from the combined areas obtained by said area-combining means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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Specification