Patent ID: 6094223
Filing Date: 2000-07-25
Classification: G02B

Abstract:
An automatic focus sensing device which senses an in-focus position by using a high-frequency component in an image signal to step drive an imaging lens in a direction of an optical axis of the imaging lens, said image signal being read in succession to a photoelectrical conversion and then integration of light of an object incident on an image pickup device,said automatic focus sensing device generating, in non-synchronization with and independently of an image synchronization signal, a driving pulse fed to an imaging lens driving device for driving the imaging lens, wherein a number of steps for step driving the imaging lens take place during an interval lying within an interval for integration, said number of steps for step driving the imaging lens establishing an imaging lens position corresponding to a high frequency, component in an image signal, said image signal being read successively during integration within said integration interval.