Patent ID: 8766153

Claim:
A vision measuring device, comprising: imaging device which images a measurement target and transfers image information representing an image of the measurement target; position control device which controls an in-focus position of the imaging device and outputs the in-focus position as position information representing a position in an in-focus axis direction; and vision measuring device which performs vision measurement on the measurement target based on the image information and the position information, wherein: the position control device acquires and retains the position information in response to a trigger signal which is output from one of the imaging device and the position control device to the other of them at a certain timing of an imaging period during which the imaging device images the measurement target; and the vision measuring device calculates position information representing a position of the image information in the in-focus axis direction based on the image information transferred from the imaging device and the position information output from the position control device, and performs auto-focusing control by using the calculated position information.