US5619264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic focusing device
Assignee: Canon Inc
•
Filing: 1994-02-23
•
Granted: 1997-04-08
•
Expires: 2014-02-23
Abstract
Abstract In the automatic focusing device having an object image variation detecting circuit for quantitatively detecting a variation of an object image on the image pickup plane of an image pickup element so that the focusing operation is controlled in accordance with the amount of variation of the object image detected by the object image variation detecting circuit, there are provided a stop control circuit for controlling the period for stopping the focusing operation when panning depending on whether the amount of variation of the object image is large or small, a characteristic varying circuit for varying the frequency band of the picked-up image signal to be used in the focus detection depending on whether the amount of variation of the object image at the time of the focusing operation is large or small, and a pass characteristic varying circuit for varying the focus detection area on the image pickup plane depending on whether the amount of variation of the object image is large or small.
Inventors
- 👤 Katsuji Yoshimura
- 👤 Masamichi Toyama
- 👤 Akihiro Fujiwara
- 👤 Kunihiko Yamada
- 👤 Hirofumi Suda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:22
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/60; H04N23/67; H04N23/675
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
199 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plan to an electrical signal; (B) gate means for passing only a part of a picked-up image signal produced from said image pickup means, said part corresponding to a focus detecting area defined on said image pickup plane; (C) object image variation detecting means for detecting an amount of a variation of the object image on said image pickup plane including a coding circuit for converting a predetermined component of the image signal in each of a plurality of areas defined on said image pickup plane to a digital value with respect to a predetermined threshold level and a discrimination circuit for comparing an output of said coding circuit with an output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas and to output an information relative to the amount of a variation of the object image; and (D) gate control means for controlling said gate means to change the size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 2
Dependent Claim
199 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plan to an electrical signal; (B) gate means for passing only a part of a picked-up image signal produced from said image pickup means, said part corresponding to a focus detecting area defined on said image pickup plane; (C) object image variation detecting means for detecting an amount of a variation of the object image on said image pickup plane including a coding circuit for converting a predetermined component of the image signal in each of a plurality of areas defined on said image pickup plane to a digital value with respect to a predetermined threshold level and a discrimination circuit for comparing an output of said coding circuit with an output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas and to output an information relative to the amount of a variation of the object image; and (D) gate control means for controlling said gate means to change the size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 3
Dependent Claim
37 words
A device according to claim 1, wherein said gate means sets large and small focus detecting areas on said image pickup plane and selectively passes the picked-up image signals corresponding to each of said focus detecting areas.
Claim 4
Dependent Claim
27 words
A device according to claim 2, wherein said object image variation detecting means quantitatively detects the amount of variation of the object image in each predetermined period.
Claim 5
Dependent Claim
49 words
A device according to claim 3, wherein said object image variation detecting means detects a variation of the picked-up image signal in each of a plurality of areas set on said image pickup plane, and computes the detection result in each area to detect the total amount of variation.
Claim 6
Dependent Claim
132 words
A device according to claim 4, wherein said object image variation detecting means includes: (A) a binary coding circuit for converting a brightness value of the picked-up image signal in each of the plurality of areas set on said image pickup plane to a binary value with respect to a predetermined threshold level; (B) a discrimination circuit for comparing an output of said binary coding circuit with the output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas; and (C) a counter for counting the number of said areas in which the presence of the variation is discriminated by said discrimination circuit, so that the variation of the object image can be quantitatively detected from an output of said counter.
Claim 7
Dependent Claim
99 words
A device according to claim 2 or 5, wherein said gate control means changes over the pass characteristic of said gate means such that the picked-up image signal corresponding to the large focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation of the object image detected by said object image variation detecting means is above a predetermined value, and the picked-up image signal corresponding to the small focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation is below the predetermined value.
Claim 8
Dependent Claim
70 words
A device according to claim 6, wherein said object image variation detecting means is arranged to transversely and longitudinally divide said image pickup plane into a plurality of blocks, to detect a binary value of a brightness value of each of said blocks and to obtain a total amount of the blocks where variations occur in picture planes at different times, as an amount of variation of the picture planes.
Claim 9
Dependent Claim
63 words
A device according to claim 1 or 7, further comprising: (A) focus detecting means for detecting a focus degree on the basis of said part of the picked-up image signal corresponding to said focus detecting area passed by said gate means; and (B) focus adjusting means for adjusting a focus condition of said apparatus according to an output of said focus detecting means.
Claim 10
Dependent Claim
22 words
A device according to claim 8, wherein said focus degree is a level of a high frequency component in said image signal.
Claim 11
Dependent Claim
183 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical image signal; (B) photographic optical system control means for automatically controlling a photographic optical system toward an in-focus position based on the picked-up image signal produced from said image pickup means; (C) gate means for passing a part of the image signal produced from said image pickup means, said part corresponding to a focus detecting area on said image pickup plane; (D) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for comparing the digital signal obtained by said coding circuit means with the digital signal output from said coding circuit means before a predetermined period of time to detect the amount of variation of the object image on said image pickup plane; and (E) control means for controlling said gate means to change a size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 12
Dependent Claim
183 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical image signal; (B) photographic optical system control means for automatically controlling a photographic optical system toward an in-focus position based on the picked-up image signal produced from said image pickup means; (C) gate means for passing a part of the image signal produced from said image pickup means, said part corresponding to a focus detecting area on said image pickup plane; (D) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for comparing the digital signal obtained by said coding circuit means with the digital signal output from said coding circuit means before a predetermined period of time to detect the amount of variation of the object image on said image pickup plane; and (E) control means for controlling said gate means to change a size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 13
Dependent Claim
45 words
A device according to claim 10, wherein said gate means sets at least two, large and small, focus detecting areas on said image pickup plane and selectively sets the large or small focus detecting area, depending upon an output of said object image variation means.
Claim 14
Dependent Claim
96 words
A device according to claim 11, wherein said control means changes over the pass characteristic of said gate means such that the picked-up image signal corresponding to the large focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation of the object image detected by said object image variation detecting means is above a predetermined value, and the picked-up image signal corresponding to the small focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation is below the predetermined value.
Claim 15
Dependent Claim
27 words
A device according to claim 10, wherein said object image variation detecting means quantitatively detects the amount of variation of the object image in each predetermined period.
Claim 16
Dependent Claim
49 words
A device according to claim 13, wherein said object image variation detecting means detects a variation of the picked-up image signal in each of a plurality of areas set on said image pickup plane, and computes the detection result in each area to detect the total amount of variation.
Claim 17
Dependent Claim
132 words
A device according to claim 14, wherein said object image variation detecting means includes: (A) a binary coding circuit for converting a brightness value of the picked-up image signal in each of the plurality of areas set on said image pickup plane to a binary value with respect to a predetermined threshold level; (B) a discrimination circuit for comparing an output of said binary coding circuit with the output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas; and (C) a counter for counting the number of said areas in which the presence of the variation is discriminated by said discrimination circuit, so that the variation of the object image can be quantitatively detected from an output of said counter.
Claim 18
Dependent Claim
180 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical image signal; (B) extracting means for extracting the image signal of a predetermined frequency component from the image signal from said image pickup means in passing therethrough; (C) gate means for passing a part of the image signal produced from said image pickup means, said part corresponding to a focus detecting area defined on said image pickup plane; (D) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for comparing the digital signal obtained by said coding circuit means with the digital signal output from said coding circuit means before a predetermined period of time to detect the amount of variation of the object image on said image pickup plane; and (E) control means for controlling said gate means to change a size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 19
Dependent Claim
180 words
An automatic focusing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical image signal; (B) extracting means for extracting the image signal of a predetermined frequency component from the image signal from said image pickup means in passing therethrough; (C) gate means for passing a part of the image signal produced from said image pickup means, said part corresponding to a focus detecting area defined on said image pickup plane; (D) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for comparing the digital signal obtained by said coding circuit means with the digital signal output from said coding circuit means before a predetermined period of time to detect the amount of variation of the object image on said image pickup plane; and (E) control means for controlling said gate means to change a size of said focus detecting area in response to an output of said object image variation detecting means.
Claim 20
Dependent Claim
98 words
A device according to claim 16, wherein said pass characteristic varying means changes over the pass characteristic of said gate means such that the picked-up image signal corresponding to the large focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation of the object image detected by said object image variation detecting means is above a predetermined value, and the picked-up image signal corresponding to the small focus detecting area on said image pickup plane is caused to pass therethrough when the amount of variation is below the predetermined value.
Claim 21
Dependent Claim
27 words
A device according to claim 16, wherein said object image variation detecting means quantitatively detects the amount of variation of the object image in each predetermined period.
Claim 22
Dependent Claim
49 words
A device according to claim 18, wherein said object image variation detecting means detects a variation of the picked-up image signal in each of a plurality of areas set on said image pickup plane, and computes the detection result in each area to detect the total amount of variation.
Claim 23
Dependent Claim
132 words
A device according to claim 19, wherein said object image variation detecting means includes: (A) a binary coding circuit for converting a brightness value of the picked-up image signal in each of the plurality of areas set on said image pickup plane to a binary value with respect to a predetermined threshold level; (B) a discrimination circuit for comparing an output of said binary coding circuit with the output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas; and (C) a counter for counting the number of said areas in which the presence of the variation is discriminated by said discrimination circuit, so that the variation of the object image can be quantitatively detected from an output of said counter.
Claim 24
Dependent Claim
117 words
An object image variation detecting device comprising: (A) image pickup means; (B) binary coding means for comparing a brightness component of a picked-up image signal corresponding to each of a plurality of areas set on an image pickup plane of said image pickup means with a predetermined valued to produce an output in binary form; (C) comparing means for comparing a brightness value of each of said areas binary-coded by said binary coding means with the brightness value of each of said areas produced a predetermined period before; and (D) a counter for counting and outputting the number of said areas in which a variation before and after said predetermined period is detected by said comparing means.
Claim 25
Dependent Claim
117 words
An object image variation detecting device comprising: (A) image pickup means; (B) binary coding means for comparing a brightness component of a picked-up image signal corresponding to each of a plurality of areas set on an image pickup plane of said image pickup means with a predetermined valued to produce an output in binary form; (C) comparing means for comparing a brightness value of each of said areas binary-coded by said binary coding means with the brightness value of each of said areas produced a predetermined period before; and (D) a counter for counting and outputting the number of said areas in which a variation before and after said predetermined period is detected by said comparing means.
Claim 26
Dependent Claim
66 words
A device according to claim 21, further comprising: (A) setting means for setting a detecting area for extracting a predetermined component from the image signal of the image pick-up means at a predetermined position of image pick-up plane of said image pick-up means; and (B) detecting area control means for changing the detecting area set by said setting means, according to the output of said counter.
Claim 27
Dependent Claim
19 words
A device according to claim 22, wherein said detecting area control means changes a size of said detecting area.
Claim 28
Independent Claim
151 words
A device for setting a detecting area on an image pickup plane of an image pickup means for converting an object image formed on an image pickup plane to an electrical image signal, comprising: (A) setting means for setting said detecting area at a predetermined position on said image pickup plane; (B) extracting means for extracting a predetermined signal component in said image signal corresponding to said detecting area; (C) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for detecting a variation of the subject image on said image pickup plane on the basis of a variation of the coded digital signal output from said coding circuit means; and (D) detecting area control means for changing a characteristic of said detecting area according to the output of said object image variation detecting means.
Claim 29
Independent Claim
151 words
A device for setting a detecting area on an image pickup plane of an image pickup means for converting an object image formed on an image pickup plane to an electrical image signal, comprising: (A) setting means for setting said detecting area at a predetermined position on said image pickup plane; (B) extracting means for extracting a predetermined signal component in said image signal corresponding to said detecting area; (C) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for detecting a variation of the subject image on said image pickup plane on the basis of a variation of the coded digital signal output from said coding circuit means; and (D) detecting area control means for changing a characteristic of said detecting area according to the output of said object image variation detecting means.
Claim 30
Dependent Claim
62 words
A device according to claim 24, wherein said detecting area control means is arranged to control said setting means on the basis of the output of said object image variation means, to change the size of said detecting area, so that said detecting area is enlarged when said variation is large and said detecting area is reduced when said variation is small.
Claim 31
Dependent Claim
38 words
A device according to claim 25, further comprising: focus adjusting means for adjusting a focusing state of said object image relative to said image pickup plane on the basis of said predetermined component extracted by said extracting means.
Claim 32
Dependent Claim
145 words
An image sensing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical signal; (B) extracting means for extracting a part of the image signal output from said image pickup means, said part corresponding to an area on said image pickup plane; (C) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for detecting an amount of a variation of the object image on said image pickup plane on the basis of a variation of the coded digital signal output from said coding circuit means; and (D) control means for controlling said extracting means to change a size of the area on said image pickup plane on the basis of an output of said image variation detecting means.
Claim 33
Dependent Claim
145 words
An image sensing device comprising: (A) image pickup means for converting an object image formed on an image pickup plane to an electrical signal; (B) extracting means for extracting a part of the image signal output from said image pickup means, said part corresponding to an area on said image pickup plane; (C) object image variation detecting means, including a coding circuit means for converting the image signal to a digital signal with respect to a predetermined threshold level, for detecting an amount of a variation of the object image on said image pickup plane on the basis of a variation of the coded digital signal output from said coding circuit means; and (D) control means for controlling said extracting means to change a size of the area on said image pickup plane on the basis of an output of said image variation detecting means.
Claim 34
Dependent Claim
26 words
A device according to claim 27, wherein said image variation detecting means quantitatively detects the amount of variation of the object image in each predetermined period.
Claim 35
Dependent Claim
48 words
A device according to claim 28, wherein said image variation detecting means detects a variation of the picked-up image signal in each of a plurality of areas set on said image pickup plane, and computes the detection result in each area to detect the total amount of variation.
Claim 36
Dependent Claim
131 words
A device according to claim 29, wherein said image variation detecting means includes: (A) a binary coding circuit for converting a brightness value of the picked-up image signal in each of the plurality of areas set on said image pickup plane to a binary value with respect to a predetermined threshold level; (B) a discrimination circuit for comparing an output of said binary coding circuit with the output produced a predetermined period before to discriminate the presence of a variation of the object image in each of said areas; and (C) a counter for counting the number of said areas in which the presence of the variation is discriminated by said discrimination circuit, so that the variation of the object image can be quantitatively detected from an output of said counter.
Claim 37
Dependent Claim
43 words
A device according to claim 27, wherein said extracting means sets at least two respectively large and small areas on said image pickup plane and selectively sets the large area or the small area, depending upon an output of said image variation means.
Claim 38
Dependent Claim
92 words
A device according to claim 31, wherein said control means changes over the pass frequency band characteristic of said extracting means such that the picked-up image signal corresponding to the large area on said image pickup plane is caused to pass therethrough when the amount of variation of the object image detected by said object image variation detecting means is above a predetermined value, and to pass therethrough the picked-up image signal corresponding to the small area on said image pickup plane when the amount of variation is below the predetermined value.
Claim 39
Dependent Claim
16 words
A device according to claim 32, wherein said small and large areas are focus detecting areas.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-04-07 | 2000-10-07 | 2001-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-04-07 | 2004-10-07 | 2005-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-04-07 | 2008-10-07 | 2009-04-08 | $7700.00 | Window Closed / Lapsed |