US5012267A
Expired / Lapsed
US
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Focus adjusting apparatus
Assignee: Canon Inc
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Filing: 1990-05-02
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Granted: 1991-04-30
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Expires: 2010-05-02
Abstract
Abstract A focus adjusting apparatus in which a functional equation representative of the imaging plane position accompanying the movement of an object to be photographed after a predetermined time is found from the result of the past focus detection, and the imaging plane position after the predetermined time is foreseen by means of the functional equation, whereby a lens is driven to the foreseen position.
Inventors
- 👤 Masaki Higashihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:03
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/34
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
206 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data introducing circuit for introducing (1) at least a first defocus amount obtained in a latest focus detection operation and second and third defocus amounts obtained in focus detection operations effected one and two times previous to said latest focus detection operation, and (2) time data representing the actual time at which the focus detection operations were performed; (b) a calculation circuit or (1) performing a first calculation to determine coefficients of a functional equation having a power greater than one wherein said equation represents movement of the imaging plane, said coefficients being determined on the basis of said first, second, and third defocus amounts and time data corresponding thereto, and for (2) performing a second calculation in which the imaging plane position or a lens driving amount corresponding to said imaging plane position is determined on the basis of the functional equation, coefficients of which have been determined by said first calculation; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 2
Dependent Claim
206 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data introducing circuit for introducing (1) at least a first defocus amount obtained in a latest focus detection operation and second and third defocus amounts obtained in focus detection operations effected one and two times previous to said latest focus detection operation, and (2) time data representing the actual time at which the focus detection operations were performed; (b) a calculation circuit or (1) performing a first calculation to determine coefficients of a functional equation having a power greater than one wherein said equation represents movement of the imaging plane, said coefficients being determined on the basis of said first, second, and third defocus amounts and time data corresponding thereto, and for (2) performing a second calculation in which the imaging plane position or a lens driving amount corresponding to said imaging plane position is determined on the basis of the functional equation, coefficients of which have been determined by said first calculation; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 3
Dependent Claim
23 words
An apparatus according to claim 1, wherein said functional equation is represented by X=at 2 +bt+c where X is the imaging plane position.
Claim 4
Dependent Claim
41 words
An apparatus according to claim 1, wherein the imaging plane position or the lens driving amount after expiration of a predetermined period of time is calculated in said second calculation by incorporating therein a time period of a release time lag.
Claim 5
Dependent Claim
193 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data introducing circuit for introducing (1) at least a first defocus amount obtained in a latest focus detection operation and second and third defocus amounts obtained in focus detection operations effected one and two times previous to said latest focus detection operation, and (2) time data representing the actual time at which the focus detection operations were performed; (b) a calculation circuit for performing a first calculation in which coefficients a, b of a formula X=at 2 +bt+c representing the movement of the imaging plane are determined on the basis of said three defocus amounts and time data, and for performing a second of calculation in which X representing the imaging plane after a predetermined period of time or a lens driving amount corresponding to said X is determined by substituting a,b obtained in said first calculation in said formula; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 6
Dependent Claim
193 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data introducing circuit for introducing (1) at least a first defocus amount obtained in a latest focus detection operation and second and third defocus amounts obtained in focus detection operations effected one and two times previous to said latest focus detection operation, and (2) time data representing the actual time at which the focus detection operations were performed; (b) a calculation circuit for performing a first calculation in which coefficients a, b of a formula X=at 2 +bt+c representing the movement of the imaging plane are determined on the basis of said three defocus amounts and time data, and for performing a second of calculation in which X representing the imaging plane after a predetermined period of time or a lens driving amount corresponding to said X is determined by substituting a,b obtained in said first calculation in said formula; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 7
Dependent Claim
39 words
An apparatus according to claim 4, wherein the imaging plane position or the lens driving amount after a predetermined period of time is calculated in said second calculation by incorporating therein a time period of a release time lag.
Claim 8
Dependent Claim
175 words
A focus adjusting apparatus in which detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data circuit for determining first, second, and third defocus amounts obtained in focus detection operations performed at three different times, said three defocus amounts including at least two defocus amounts obtained in focus detection operations performed in the past; (b) a calculation circuit for performing a first calculation to determine coefficients of a higher-order functional equation representing a movement of the imaging plane on the basis of said first, second, and third defocus amounts and time data corresponding thereto, and for performing a second calculation in which the imaging plane position or a lens driving amount corresponding to said imaging plane position is determined on the basis of the higher-order functional equation, the coefficients of which have been determined in said first calculation; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 9
Dependent Claim
175 words
A focus adjusting apparatus in which detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising: (a) a data circuit for determining first, second, and third defocus amounts obtained in focus detection operations performed at three different times, said three defocus amounts including at least two defocus amounts obtained in focus detection operations performed in the past; (b) a calculation circuit for performing a first calculation to determine coefficients of a higher-order functional equation representing a movement of the imaging plane on the basis of said first, second, and third defocus amounts and time data corresponding thereto, and for performing a second calculation in which the imaging plane position or a lens driving amount corresponding to said imaging plane position is determined on the basis of the higher-order functional equation, the coefficients of which have been determined in said first calculation; and (c) a lens driving circuit for driving the lens on the basis of the result of said second calculation.
Claim 10
Dependent Claim
161 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said focus amount are repeatedly effected, said apparatus, comprising: (a) a data circuit for detecting data obtained in a focus detecting operation performed in the past, the data detected by said data circuit being renewed whenever the focus detection operation is performed, a predetermined number of the latest focus adjusting data including the present data being input to said data circuit; (b) a calculation circuit fox calculating an imaging plane position a lens driving amount corresponding to said imaging plane position after expiration of a predetermined period of time on the basis of the data obtained by said data circuit, said calculation being performed whenever said data are renewed, and said predetermined time including a release time lag; and (c) a lens driving circuit for driving the lens on the basis of the calculation performed by said calculation circuit.
Claim 11
Dependent Claim
161 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said focus amount are repeatedly effected, said apparatus, comprising: (a) a data circuit for detecting data obtained in a focus detecting operation performed in the past, the data detected by said data circuit being renewed whenever the focus detection operation is performed, a predetermined number of the latest focus adjusting data including the present data being input to said data circuit; (b) a calculation circuit fox calculating an imaging plane position a lens driving amount corresponding to said imaging plane position after expiration of a predetermined period of time on the basis of the data obtained by said data circuit, said calculation being performed whenever said data are renewed, and said predetermined time including a release time lag; and (c) a lens driving circuit for driving the lens on the basis of the calculation performed by said calculation circuit.
Claim 12
Dependent Claim
27 words
A focus adjusting device according to claim 7, wherein said data obtained in said focus detecting operation is a defocus amount obtained by said focus detection circuit.
Claim 13
Dependent Claim
28 words
A focus adjusting device according to claim 7, wherein said release time lag is a time period from a releasing operation to the opening of a shutter member.
Claim 14
Dependent Claim
156 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising; (a) a data circuit for repeatedly detecting focus adjusting data obtained in the past by said focus detection circuit; (b) a calculation circuit for calculating an imaging plane position or a lens driving amount corresponding to said imaging plane position at a time after a predetermined period of time including a release time lag has passed on the basis of the data obtained by said data circuit, said calculation circuit repeatedly obtaining data of said imaging plane position or lens driving amount for an object in the future after expiration of a predetermined period of time including the release time lag; and (c) a lens driving circuit for driving the lens on the basis of the result of the calculation performed by said calculation circuit.
Claim 15
Dependent Claim
156 words
A focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to said defocus amount are repeatedly effected, said apparatus, comprising; (a) a data circuit for repeatedly detecting focus adjusting data obtained in the past by said focus detection circuit; (b) a calculation circuit for calculating an imaging plane position or a lens driving amount corresponding to said imaging plane position at a time after a predetermined period of time including a release time lag has passed on the basis of the data obtained by said data circuit, said calculation circuit repeatedly obtaining data of said imaging plane position or lens driving amount for an object in the future after expiration of a predetermined period of time including the release time lag; and (c) a lens driving circuit for driving the lens on the basis of the result of the calculation performed by said calculation circuit.
Claim 16
Dependent Claim
27 words
A focus adjusting device according to claim 10, wherein said data obtained in said focus detecting operation is a defocus amount obtained by said focus detection circuit.
Claim 17
Dependent Claim
28 words
A focus adjusting device according to claim 10, wherein said release time lag is a time period from a releasing operation to the opening of a shutter member.
Claim 18
Dependent Claim
124 words
A camera including a focus adjusting apparatus in which detection of a defocus amount by a focus detection circuit and lens driving according to the detected defocus amount are repeatedly effected, said camera comprising: (a) a data circuit for determining at least first, second, and third defocus amounts obtained in focus detection operations performed at three different times; (b) a calculation circuit for performing a calculation to determine an imaging plane position or a lens driving amount on the basis of a higher-order functional equation, wherein coefficients of said higher-order functional equation are determined on the basis of said first, second, and third defocus amounts; and (c) a lens driving circuit for driving the lens on the basis of the result of said calculation.
Claim 19
Dependent Claim
124 words
A camera including a focus adjusting apparatus in which detection of a defocus amount by a focus detection circuit and lens driving according to the detected defocus amount are repeatedly effected, said camera comprising: (a) a data circuit for determining at least first, second, and third defocus amounts obtained in focus detection operations performed at three different times; (b) a calculation circuit for performing a calculation to determine an imaging plane position or a lens driving amount on the basis of a higher-order functional equation, wherein coefficients of said higher-order functional equation are determined on the basis of said first, second, and third defocus amounts; and (c) a lens driving circuit for driving the lens on the basis of the result of said calculation.
Claim 20
Dependent Claim
160 words
A camera including a focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to the detected defocus amount are repeatedly effected, said camera comprising: (a) a data circuit for repeatedly detecting focus adjusting data obtained in the past by said focus detection circuit; (b) a calculation circuit for calculating an imaging plane position or a lens driving amount corresponding to said imaging plane position at a time after a predetermined period of time including a release time lag has passed on the basis of the data obtained by said data circuit, said calculation circuit repeatedly obtaining data of said imaging plane position or lens driving amount for an object in the future after expiration of a predetermined period of time including the release time lag; and (c) a lens driving circuit for driving the lens on the basis of the result of the calculation performed by said calculation circuit.
Claim 21
Dependent Claim
160 words
A camera including a focus adjusting apparatus in which a detection of a defocus amount by a focus detection circuit and lens driving according to the detected defocus amount are repeatedly effected, said camera comprising: (a) a data circuit for repeatedly detecting focus adjusting data obtained in the past by said focus detection circuit; (b) a calculation circuit for calculating an imaging plane position or a lens driving amount corresponding to said imaging plane position at a time after a predetermined period of time including a release time lag has passed on the basis of the data obtained by said data circuit, said calculation circuit repeatedly obtaining data of said imaging plane position or lens driving amount for an object in the future after expiration of a predetermined period of time including the release time lag; and (c) a lens driving circuit for driving the lens on the basis of the result of the calculation performed by said calculation circuit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-04-29 | 1994-10-29 | 1995-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-04-29 | 1998-10-29 | 1999-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-04-29 | 2002-10-29 | 2003-04-30 | $7700.00 | Window Closed / Lapsed |