Focusing apparatus, focusing method and medium for recoring the focusing method
AssigneeSamsung Electronics Co., Ltd.
InventorMasataka Hamada
Life of this patent
Estimating the term…
Abstract
Provided are a focusing apparatus for generating an image signal by converting image light incident through a focus lens to an electrical signal by an image pickup device, storing the image signal in a memory, calculating an AF evaluation value for an image signal read from the memory in a direction different from a reading direction of the image pickup device, and driving the focus lens by deriving a focus lens position corresponding to the calculated AF evaluation value, a focusing method thereof, and a recording medium for recording the focusing method. Accordingly, a focus can be correctly adjusted for various subject images, and a focus can be effectively adjusted for the images even in a high speed capturing mode.
Claims27
A focusing apparatus comprising:
- a focus lens;
- a focus lens driver configured to drive the focus lens in an optical axis direction;
- an image pickup device configured to generate an image signal by converting image light incident through the focus lens to an electrical signal;
- a memory configured to store the image signal provided by the image pickup device;
- a focus evaluation value deriver configured to derive a first focus evaluation value by reading a first image signal generated by the image pickup device in a first direction while moving the focus lens in one direction and to derive a second focus evaluation value by storing a second image signal in the memory and reading the second image signal in a second direction that is different from the first direction from the memory, wherein the second image signal is generated by the image pickup device while moving the focus lens in the other direction;
- a peak value deriver configured to derive a first peak value of the first focus evaluation value and a second peak value of the second focus evaluation value;
- and
- a focus lens position deriver configured to derive a focus lens position corresponding to one of the peak values.
A focusing method comprising:
- generating, by an image pickup device, a first image signal while moving a focus lens in one direction;
- deriving a first focus evaluation value by reading the first image signal in a first direction from the image pickup device;
- generating a second image signal while moving the focus lens in the other direction;
- storing the second image signal;
- deriving a second focus evaluation value by reading the stored image signal in a second direction that is different from the first direction;
- deriving a first peak value of the first focus evaluation value and a second peak value of the second focus evaluation value;
- and
- deriving a focus lens position corresponding to at least one of the peak values.
A non-transitory computer program product, comprising a computer usable medium having a computer readable program code embodied therein, said computer readable program code adapted to be executed to implement a method of focusing, said method comprising:
- generating, by an image pickup device, a first image signal while moving a focus lens in one direction;
- deriving a first focus evaluation value by reading the first image signal in a first direction from the image pickup device;
- generating a second image signal while moving the focus lens in the other direction;
- storing the second image signal;
- deriving a second focus evaluation value by reading the stored image signal in a second direction that is different from the first direction;
- deriving a first peak value of the first focus evaluation value and a second peak value of the second focus evaluation value;
- and
- deriving a focus lens position corresponding to at least one of the peak values.
Dependencies are inferred from the claim text.