US 4,305,657 A · Range finding device

Abstract

This invention presents a range finding device when 1st and 2nd detection images of an object are scanned by signal storing type image sensing means to obtain image scan signals, which are quantized by quantization means to produce quantized image data for said 1st and 2nd detection images. On the basis of the thus obtained quantized image data, the location within the 2nd detection images of one set of M successive elements of the 2nd detection image which is most similar to M successive elements of the 1st detection image is detected, and with the aid of the data of this location, the distance between the device and the object is determined. According to this improved device, sequence control means, which controls a series of operations for range finding, will firstly cancel the signals stored in said image sensing means as unnecessary signals, when said series of operations is initiated, and then enables proper storing of image signals in the image sensing means so as to properly control the device.

Claims40

Dependent claims

A range detecting device for detecting the range of an object, comprising:

(A) signal integration and storing type image sensing means including a plurality of sensing elements arranged to receive first and second detection images of said object to provide an image element signal for each image element of the first and second detection images;
(B) means for producing a specific level on the basis of the levels of the image element signals on M successive image elements of the first detection image;
(C) integration state detection means for detecting, on the basis of said specific level produced by said specific level producing means, whether or not the signal integration time of the sensing means is proper, said integration state detection means providing a characteristic output when it detects that the signal integration time of the sensing means is improper;
(D) integration control means for controlling integration of the signals in the image sensing means which correspond to each image element of the first and second detection images, said integration control means being responsive to said characteristic output of said integration state detection means and automatically changing the signal integration time of the image sensing means on the basis of the characteristic output of the integration state detection means;
(E) quantization means for quantizing the image element signal generated for each image element by said image sensing means;
(F) circuit means for receiving quantized data from said quantization means and detecting, on the basis of said quantized data, the relative positional difference between said M successive image elements of the first detection image and M successive image elements of the second detection image corresponding to the M successive image elements of the first detection image so as to provide data on the range of the object;
(G) quantization state detection means for detecting whether or not all of the quantized data on said M successive image elements of the first detection image are one and the same data, said quantization state detection means providing a characteristic output when it detects that all of the quantized data on the M successive image elements of the first detection image are one and the same data;
and
(H) control means for controlling at least one of the outputs of the device and the operation of the device on the basis of the characteristic output of said quantization state detection means.

6 more elements

A range detecting device for detecting the range of an object, comprising:

(A) image sensing means including a plurality of sensing elements arranged to receive first and second detection images of said object to provide an image element signal for each image element of the first and second detection images;
(B) quantization means for quantizing the image element signal generated for each image element by said image sensing means;
(C) circuit means for receiving the quantized data from said quantization means and detecting, on the basis of said quantized data, the relative positional difference between M successive image elements of the first detection image and M successive image elements of the second image corresponding to the M successive image elements of the first detection image so as to provide data on the range of the object, said circuit means including:
similarity detection means for detecting, on the basis of the quantized data, the similarity of each of different sets of M successive image elements of the second detection image to the M successive image elements of the first detection image;
and
maximum similarity detection means for detecting maximum similarity within the detected similarities detected by said similarity detection means so as to determine said M successive image elements of the second detection image corresponding to the M successive image elements of the first detection image;
(D) evaluating means for evaluating the maximum similarity detected by said maximum similarity detection means, said evaluating means comparing the maximum similarity with a predetermined constant value to provide a characteristic output when the maximum similarity detected by said maximum similarity detection means is smaller than said predetermined value;
and
(E) control means for controlling the output of the device on the basis of the state of comparison output of the evaluating means so as to regulate the output of the device in response to the characteristic output of said evaluating means.

6 more elements

In a range detecting device for detecting the range of an object, comprising:

(A) signal integration and storing type image sensing means including a plurality of sensing elements arranged to receive first and second detection images of said object to provide an image element signal for each image element of said first and second detection images;
(B) integration control means for controlling, on the basis of the brightness of the object, a period for integration of the signals in the image sensing means which correspond to each image element of the first and second detection images;
and
(C) circuit means for receiving the image element signals from said image sensing means and detecting, on the basis of said image element signals, the relative positional difference between M successive image elements of said first detection image and a set of M successive image elements among a plurality of different sets of M successive image elements of said second detection image corresponding to said M successive elements of said first detection image so as to provide data for the range of the object, the improvement comprising:
(D) means for forming additionally a limited target of radiation on said object, said target forming means being arranged in such a manner that the target forming means is operated only during a period corresponding to a period in which the integration of the signals in the image sensing means is effected to a substantial extent and that, when the target forming means is operated, first and second images of said limited target of radiation are respectively included within said M successive image elements of the first detection image and said one set of M successive image elements of the second detection image corresponding to the M successive image elements of the first detection image on said image sensing means;
whereby when said target forming means is operated, said circuit means provides said range data by detecting the relative positional difference between M successive image elements of the first detection image including the first radiation target image and a set of M successive image elements of the second detection image including the second radiation target image and corresponding to the M successive image elements of the first detection image including said first radiation target image.

3 more elements

In a range detecting device for detecting the range of an object, comprising:

(A) signal integration and storing type image sensing means including a plurality of sensing elements arranged to receive first and second detection images of said object to provide an image element signal for each image element of the first and second detection images;
(B) integration control means for controlling, on the basis of the brightness of the object, a period for integration of the signals in the image sensing means which correspond to each image element of the first and second detection images;
(C) quantization means for quantizing the image element signal generated for each image element by said image sensing means;
and
(D) circuit means for receiving quantized data from said quantization means and detecting the relative positional difference, on the basis of said quantized data, between M successive image elements of the first detection image and M successive image elements of the second image corresponding to the M successive image elements of the first detection image so as to provide data regarding the range of the object, the improvement comprising:
(E) means for forming additionally a limited target of radiation on said object, said target forming means being arranged in such a manner that the target forming means is operated only during a period corresponding to a period in which the integration of the signals in the image sensing means is effected to a substantial extent and that, when the target forming means is operated, first and second images of said limited target of radiation are respectively included within said M successive image elements of the first detection image and said one set of M successive image elements of the second detection image corresponding to the M successive image elements of the first detection image on said image sensing means;
whereby when said target forming means is operated, said circuit means provides said range data by detecting the relative positional difference between M successive image elements of the first detection image including the first radiation target image and a set of M successive image elements of the second detection image including the second radiation target image and corresponding to the M successive image elements of the first detection image including said first radiation target image.

4 more elements

A distance detecting device for detecting the distance of an object, comprising:

(A) signal integration and storing type image sensing means including a plurality of sensing elements arranged to receive first and second detection images of said object to provide an image element signal for each image element of said first and second detection images;
(B) quantization means for receiving and quantizing the image element signal generated for each image element of the first and second detection images to provide quantized data on each image element;
(C) storing means for storing the quantized data on M successive image elements of the first detection image and the quantized data on successive image elements, the image element number of which is greater than said number M, of the second detection image;
(D) detection means for detecting, on the basis of the stored quantized data stored in said storing means, the relative positional difference between said M successive image elements of the first detection means and a set of M successive image elements of the second detection image corresponding to the M successive image elements of the first detection image so as to provide data on the object distance;
(E) peak detection means for receiving from said sensing means the image element signals on said M successive image elements of the first detection image and for detecting a peak level of the received image element signals;
and
(F) integration time control means for controlling signal integration time of said sensing means on the basis of the peak level detected by said peak detection means.

4 more elements

A system for focusing an objective lens means onto an object, comprising:

(A) means for detecting the range of the object, said range detection means providing data on the object range in a digital word;
(B) means for moving said objective lens means from a predetermined position on an optical axis thereof along the optical axis in a predetermined direction, said moving means including means for storing a force for moving said objective lens means from said predetermined position in said predetermined direction, said force storing means being arranged to store the force therein when the objective lens means is set to the predetermined position;
(C) manually releasable latching means for retaining said objective lens means at said predetermined position against the force stored in said force storing means, said objective lens means being moved from said predetermined position in said predetermined direction by the force stored in the force storing means when the latching by said latching means is released;
(D) means for producing electrical pulses in association with the movement of the objective lens means from said predetermined position, the number of said pulses being indicative of the moving amount of the objective lens means from the predetermined position;
(E) means receiving the object range data from said range detection means and the electrical pulses from said pulse producing means to detect whether the objective lens means has reached a focused position to the object, said focus detection means including pulse count means for counting said electrical pulses produced from the pulse producing means and providing a characteristic output when it detects that the objective lens means has reached said focused position, said pulse count means including a presettable down-counter adapted to have preset therein the range data provided by said range detection means and being operative to count down in response to the electrical pulses produced from said pulse producing means, said counter providing a carry output as said characteristic output;
and
(F) means responsive to the characteristic output of said focus detection means to stop said objective lens means at said focused position.

4 more elements

A range detection system for detecting the range of an object, comprising:

(A) means for receiving first and second detection images of said object and for providing image signals on said first and second detection images;
(B) means for detecting, on the basis of the image signals provided by said image receiving means, the range of said object, said range detection means detecting the object range by detecting, on the basis of said image signals, the relative positional difference between corresponding image portions of said first and second detection images and providing data on the object range;
(C) means for controlling the operation for the range detection of said range detection means, said control means being operable for causing the range detection means to repeat the range detecting operation at a predetermined cycle;
(D) means for memorizing the range data provided by said range detection means at the termination of each cycle of range detecting operation of the range detection means;
(E) means for comparing, at the termination of each range detecting operation cycle of said range detection means, the range data newly provided by the range detection means at the termination of a new operation cycle with the former range data provided by the range detection means at the termination of the former operation cycle and memorized in said memory means, said comparison means detecting the difference between said newly provided range data and said former range data and providing a characteristic output when said difference is greater than a predetermined value;
and
(F) means responsive to the characteristic output of said comparison means to invalidate said newly provided range data.

4 more elements

In a focusing system for focusing an adjustable objective lens means onto an object, the combination comprising:

(A) means for receiving first and second detection images of said object and for providing image signals on said first and second detection images;
(B) means for detecting, on the basis of the image signals provided by said image receiving means, the range of said object, said range detection means detecting the object range by detecting, on the basis of said image signals, the relative positional difference between corresponding image portions of said first and second detection images and providing data on the object range;
(C) means for moving said objective lens means from a predetermined position on an optical axis thereof along the optical axis in a predetermined direction, said moving means including means for storing a force forming said objective lens means from said predetermined position in said predetermined direction, said force storing means being arranged to store the force therein when the objective lens means is set to the predetermined position;
(D) manually releasable latching means for retaining said objective lens means at said predetermined position against the force stored in said force storing means, said objective lens means being moved from said predetermined position in said predetermined direction by the force stored in the force storing means when the latching by said latching means is released;
(E) means for producing electrical pulses in association with movement of the objective lens means from said predetermined position, the number of said pulses being indicative of the amount of movement of the objective lens means from the predetermined position;
(F) means for receiving the object range data from said range detection means and the electrical pulses from said pulse producing means to detect whether the objective lens means has reached a focused position to the object, said focusing detection means including pulse count means for counting said electrical pulses produced from the pulse producing means and providing a characteristic output when it detects that the objective lens means has reached said focused position, said count means including a presettable down-counter adapted to have preset therein the range data provided by said range detection means and being operative to count down in response to the electrical pulse produced from said pulse producing means, said counter providing a carry output as said characteristic output;
and
(G) means responsive to the characteristic output of said focus detection means to stop said objective lens means at said focused position.

5 more elements

In a focus detection system for detecting the focus of an adjustable objective lens means onto an object, the combination comprising:

(A) means for receiving first and second detection images of said object and for providing image signals on said first and second detection images;
(B) means for detecting, on the basis of the image signals provided by said image receiving means, the range of said object, said range detection means detecting the object range by detecting, on the basis of said image signals, the relative positional difference between corresponding image portions of said first and second detection images and providing data on the object range;
(C) means operatively associated with said objective lens means for providing data on an adjusted position of the lens means along an optical axis thereof;
(D) means for detecting, on the basis of the object range data provided by said range detection means and the data on the adjusted position of the lens means provided by said position data providing means, deviation of the adjusted position of said objective lens means from an in-focus position, at which the lens means is properly focused onto the object, said deviation detection means providing data on said deviation;
(E) means for controlling the operation for deviation detection of said deviation detection means, said control means being operable for causing the deviation detection means to repeat the deviation detecting operation at a predetermined cycle;
(F) means for detecting, on the basis of the deviation data provided by said deviation detection means, whether or not said objective lens means is set to said in-focus position, said in-focus detection means providing an in-focus signal when it detects that the objective lens means is set to the in-focus position;
(G) means for comparing, at the termination of each cycle of the deviation detecting operation of said deviation detection means, the deviation data with a predetermined value, said comparison means providing a characteristic output when it detects that the deviation data is smaller than said predetermined value;
and
(H) means responsive to the in-focus signal provided by said in-focus detection means and the characteristic output of said comparison means to invalidate the deviation data provided by said deviation detection means, said invalidating means, when it receives the in-focus signal from the in-focus detection means, invalidating the deviation data provided by the deviation detection means at the termination of next operation cycle in response to the characteristic output of the comparison means.

6 more elements

Dependencies are inferred from the claim text.

Range finding device

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Range finding device

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Abstract

Claims40