Mitutoyo Corporation

Nobuo Ohba

Shiro Igasaki

Koji Kubo

Yuki Kurahashi

Takahisa Ootake

Satoru Yoshida

Tatsuya Nagahama

Hiroki Matsui

Hiroshi Sakai

Masanori Arai

Yutaka Watanabe

Yuko Shishido

Hitoshi Isobe

Masafumi Yamanaka

Naoto Oita

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.

Image pick-up device, image measurement apparatus, non-contact displacement-detecting device and non-contact profile-measuring device

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.

Variable focal length lens device and variable focal length lens control method

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.

Growing community of inventors

Kanagawa, Japan

Nobuo Ohba