Focus adjustment device and focus adjustment method
AssigneeOlympus Corporation
InventorSatoshi Takinoiri
Life of this patent
Estimating the term…
Abstract
While a focus lens is moving to a focus lens driving target position, a controller of a focus adjustment device switches a moving speed of the focus lens from a first speed to a second speed. In particular, the controller calculates the number of times the defocus amount can be calculated when the focus lens moves at a predetermined speed in a section between a first position in which the moving speed is switched and a second position in which the focus lens starts being controlled to stop in the focus lens driving target position, and calculates the second speed based on the number of times, the first position and the focus lens driving target position.
Claims11
A focus adjustment device comprising:
- a focus detector which calculates a defocus amount of an imaging optical system including a focus lens by phase difference detection;
- and
- a controller which moves the focus lens to a focus lens driving target position to adjust a focus of the focus lens based on the defocus amount output from the focus detector,
- wherein:
- the controller switches a moving speed of the focus lens from a first speed to a second speed, while the focus lens is moving to the focus lens driving target position, wherein the controller
- calculates the number of times the focus detector is to calculate the defocus amount when the focus lens moves at a predetermined speed in a section between a first position in which the moving speed is switched and a second position in which the focus lens starts being controlled to stop in the focus lens driving target position, and
- calculates the second speed based on the number of times, the first position and the focus lens driving target position.
A focus adjustment method for calculating a defocus amount of an imaging optical system including a focus lens by phase difference detection and moving the focus lens to a focus lens driving target position based on the calculated defocus amount to adjust a focus of the focus lens, the method comprising:
- while the focus lens is moving to the focus lens driving target position, switching a moving speed of the focus lens from a first speed to a second speed, wherein
- the switching including:
- calculating the number of times the defocus amount is to be calculated when the focus lens moves at a predetermined speed in a section between a first position in which the moving speed is switched and a second position in which the focus lens starts being controlled to stop in the focus lens driving target position;
- and
- calculating the second speed based on the number of times, the first position and the focus lens driving target position.
Dependencies are inferred from the claim text.