Mitutoyo Corporation

Shohei Udo

Masaoki Yamagata

Shiro Igasaki

Provided is an object image measurement apparatus including an image capturing part that image-captures an object; a movement mechanism that changes an image capturing position of the image capturing part to the object; and a calculation part that calculates a correction value from a first captured image group acquired by placing the image capturing part static at each of a plurality of image capturing positions and a second captured image group acquired by relatively moving the image capturing part so as to pass each of a plurality of the image capturing positions. The first captured image group and the second captured image group are captured image groups of images captured at a plurality of the predetermined image capturing positions by the image capturing part.

Image measurement apparatus, image measurement method, information processing apparatus, information processing method, and program

An autofocus mechanism includes a light source emitting light through an objective lens at a work piece; a first detector detecting a portion of light reflected by the work piece and generating a first signal; a second detector detecting a portion of the reflected light and generating a second signal; a first amplifier amplifying the first signal and generating a first amplified signal; a second amplifier amplifying the second signal and generating a second amplified signal; an amplification rate definer defining an amplification rate of each of the first amplifier and the second amplifier based on the first amplified signal and the second amplified signal, respectively; and a calculator identifying a focal position of the objective lens based on the first amplified signal and the second amplified signal.

Autofocus mechanism

First and second amplifiers amplify a voltage value of a first signal and generate first and second amplified signals. Third and fourth amplifiers amplify the voltage value of a second signal and generate third and fourth amplified signals. A corrector corrects one of the first amplified signal and the second amplified signal based on a first correction function illustrating a relationship between the voltage value of the first amplified signal and the voltage value of the second amplified signal and generates one of a first corrected signal and a second corrected signal, and corrects one of the third amplified signal and the fourth amplified signal based on a second correction function illustrating a relationship between the voltage value of the third amplified signal and the voltage value of the fourth amplified signal and generates one of a third corrected signal and a fourth corrected signal.

Autofocus mechanism with a first and second amplification rate

A computation & control unit defines, as first and second voltages, A+B_signal voltages at distances which give the maximum and minimum voltages of an S_signal voltage, respectively. The unit further defines the higher one of the first and second voltages as an S_signal validity determination voltage and defines a distance at which the S_signal voltage takes on an in-focus determination voltage. The unit defines first and second lower limit voltages, defines the higher one of the first and second lower limit voltages as a lower limit voltage, and defines, as an upper limit voltage, an A+B_signal voltage at a distance which gives an in-focus determination voltage between the maximum and minimum positions of the S_signal voltage. An input and output unit outputs the upper and lower limit voltages as the upper and lower limit values of a settable range of the S_signal validity determination voltage.

An input tool has: an I/O unit having a digimatic interface; a first signal conversion unit that converts a measurement signal in a signal format according to an HID keyboard protocol capable of being processed by an HID driver; a second signal conversion unit that converts the measurement signal into a signal format according to a virtual serial port protocol capable of being processed by a VCP driver; a conversion controller that makes one of the first signal conversion unit and the second signal conversion unit to convert a signal format of the measurement signal; and a USB communicator having a USB interface that is connectable with a PC, the USB communicator outputting the measurement signal.

Growing community of inventors

Miyazaki, Japan

Shohei Udo