Abstract: An image measurement apparatus, which functions as a non-contact profile-measuring device, includes: an image sensor as an image pick-up device; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from a workpiece to the image sensor; and a controller (image-pickup lens controller and image measurement processor) configured to control the variable focal length lens and process a detected image by the image sensor. The image measurement apparatus, which also functions as a non-contact displacement-detecting device, includes: an image sensor; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from the workpiece to the image sensor; and a controller (displacement-detection lens controller and profile measurement processor) configured to control the variable focal length lens and a detected image by the image sensor.

Abstract: A variable focal length lens device includes: a lens system whose refractive index changes in accordance with an inputted drive signal; and a resonance-lock controller that locks the drive signal to a resonance frequency of the lens system. The resonance-lock controller tunes a frequency of the drive signal to a peak position of a voltage-current phase difference between a voltage of the drive signal and a drive current of the lens system, and raises or lowers the frequency of the drive signal in accordance with the drive current when the voltage-current phase difference changes.

Abstract: A variable focal length lens device includes: a lens system whose refractive index changes depending on an inputted drive signal; an objective lens disposed in an optical axis common to the lens system; an image detector for detecting an image of a target object through the lens system and the objective lens; a resonance-lock controller for locking the frequency of the drive signal to a resonance frequency of the lens system; and a resonance-lock operation unit for switching enabling and suspending the resonance-lock controller.

Abstract: An image measurement apparatus, which functions as a non-contact profile-measuring device, includes: an image sensor as an image pick-up device; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from a workpiece to the image sensor; and a controller (image-pickup lens controller and image measurement processor) configured to control the variable focal length lens and process a detected image by the image sensor. The image measurement apparatus, which also functions as a non-contact displacement-detecting device, includes: an image sensor; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from the workpiece to the image sensor; and a controller (displacement-detection lens controller and profile measurement processor) configured to control the variable focal length lens and a detected image by the image sensor.

Abstract: A variable focal length lens device includes: a lens system whose refractive index changes in accordance with an inputted drive signal; and a resonance-lock controller that locks the drive signal to a resonance frequency of the lens system. The resonance-lock controller tunes a frequency of the drive signal to a peak position of a voltage-current phase difference between a voltage of the drive signal and a drive current of the lens system, and raises or lowers the frequency of the drive signal in accordance with the drive current when the voltage-current phase difference changes.

Abstract: A variable focal length lens device includes: a lens system whose refractive index changes depending on an inputted drive signal; an objective lens disposed in an optical axis common to the lens system; an image detector for detecting an image of a target object through the lens system and the objective lens; a resonance-lock controller for locking the frequency of the drive signal to a resonance frequency of the lens system; and a resonance-lock operation unit for switching enabling and suspending the resonance-lock controller.