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US 9,310,226 B2Granted
Position detection apparatus, drive control apparatus, and lens apparatus
AssigneeCanon Kabushiki Kaisha
InventorTakashi Kato
Life of this patent
Estimating the term…
Abstract
A position detection apparatus includes a signal output configured to output a plurality of signals, the position detection apparatus detecting a relative position of a position detection target from a reference position on the basis of the plurality of signals, a relative position detection unit configured to detect the relative position of the position detection target from the reference position on the basis of the plurality of signals, an absolute position detection unit configured to detect an absolute position of the position detection target on the basis of the plurality of signals; and a reference position setting unit configured to set the absolute position detected by the absolute position detection unit as the reference position.
Claims7
A position detection apparatus comprising:
- a signal output unit that is arranged to be opposite to a scale unit and configured to read patterns of the scale unit and output a plurality of signals, the position detection apparatus detecting a relative position of a position detection target that moves in synchronism with the scale unit or the signal output unit from a reference position on the basis of the plurality of signals;
- a relative position detection unit configured to detect the relative position of the position detection target from the reference position on the basis of the plurality of signals;
- an absolute position detection unit configured to detect an absolute position of the position detection target on the basis of the plurality of signals;
- a reference position setting unit configured to set the absolute position detected by the absolute position detection unit as the reference position;
- and
- a state detection unit configured to detect a state of the position detection target,
- wherein the state includes a stopped state in which the position detection target is stopped, a low-speed operating state in which the position detection target is operated at a low speed, and a high-speed operating state in which the position detection target is operated at a higher speed than in the low-speed operating state,
- wherein the absolute position detection unit determines that the absolute position is used in a case where the state is the stopped state or the low-speed operating state and determines that the absolute position is not used in a case where the state is the high-speed operating state, and
- wherein the reference position setting unit sets the absolute position determined to be used by the absolute position detection unit as a confirmed reference position corresponding to the reference position that has been confirmed in a case where the state is the stopped state and sets the absolute position as a tentative reference position corresponding to the reference position that has tentatively been set in a case where the state is the low-speed operating state.
6 more elements
A drive control apparatus comprising:
- a position detection apparatus including
- a signal output unit that is arranged to be opposite to a scale unit and configured to read patterns of the scale unit and output a plurality of signals, the position detection apparatus detecting a relative position of a position detection target that moves in synchronism with the scale unit or the signal output unit from a reference position on the basis of the plurality of signals,
- a relative position detection unit configured to detect the relative position of the position detection target from the reference position on the basis of the plurality of signals,
- an absolute position detection unit configured to detect an absolute position of the position detection target on the basis of the plurality of signals, and
- a reference position setting unit configured to set the absolute position detected by the absolute position detection unit as the reference position;
- a state detection unit configured to detect a state of the position detection target,
- wherein the state includes a stopped state in which the position detection target is stopped, a low-speed operating state in which the position detection target is operated at a low speed, and a high-speed operating state in which the position detection target is operated at a higher speed than in the low-speed operating state,
- wherein the absolute position detection unit determines that the absolute position is used in a case where the state is the stopped state or the low-speed operating state and determines that the absolute position is not used in a case where the state is the high-speed operating state, and
- wherein the reference position setting unit sets the absolute position determined to be used by the absolute position detection unit as a confirmed reference position corresponding to the reference position that has been confirmed in a case where the state is the stopped state and sets the absolute position as a tentative reference position corresponding to the reference position that has tentatively been set in a case where the state is the low-speed operating state;
- and
- a drive control unit configured to drive and control the position detection target,
- wherein the drive control unit controls the position detection target in a case where the absolute position detection unit detects the absolute position.
9 more elements
A lens apparatus comprising:
- an optical member functioning as a position detection target;
- and
- a drive control apparatus including
- a position detection apparatus that includes
- a signal output unit that is arranged to be opposite to a scale unit and configured to read patterns of the scale unit and output a plurality of signals, the position detection apparatus detecting a relative position of a position detection target that moves in synchronism with the scale unit or the signal output unit from a reference position on the basis of the plurality of signals,
- a relative position detection unit configured to detect the relative position of the position detection target from the reference position on the basis of the plurality of signals,
- an absolute position detection unit configured to detect an absolute position of the position detection target on the basis of the plurality of signals, and
- a reference position setting unit configured to set the absolute position detected by the absolute position detection unit as the reference position,
- a state detection unit configured to detect a state of the position detection target,
- wherein the state includes a stopped state in which the position detection target is stopped, a low-speed operating state in which the position detection target is operated at a low speed, and a high-speed operating state in which the position detection target is operated at a higher speed than in the low-speed operating state,
- wherein the absolute position detection unit determines that the absolute position is used in a case where the state is the stopped state or the low-speed operating state and determines that the absolute position is not used in a case where the state is the high-speed operating state, and
- wherein the reference position setting unit sets the absolute position determined to be used by the absolute position detection unit as a confirmed reference position corresponding to the reference position that has been confirmed in a case where the state is the stopped state and sets the absolute position as a tentative reference position corresponding to the reference position that has tentatively been set in a case where the state is the low-speed operating state;
- and
- a drive control unit configured to drive and control the position detection target,
- wherein the drive control unit controls the position detection target in a case where the absolute position detection unit detects the absolute position.
12 more elements
Dependencies are inferred from the claim text.