Minoru Yoshii

TL;DR: In this article, a focus detecting device having detecting means for detecting the width of the edge part of the image of an object to be photographed and discriminating means for discriminating a focused state on the basis of the size of the detected width is arranged to determine by the discriminating means the apparatus to be out of focus when the image image is wide and to be in focus when it is narrow.

TL;DR: In this article, a displacement detecting system includes a scale provided on a surface of a movable object and having a diffraction grating formed along a predetermined direction, a head unit disposed above the surface of the moving object and a plurality of detection heads, for detecting displacement of the scale.

TL;DR: In this article, an inspection method and apparatus for heterodyne interference light is described, in which the first light is projected to a position of inspection, and the second light and light scattered at the inspection position and having its state of polarization changed, by the scattering, from the first state of polarisation, is detected.

TL;DR: In this paper, the authors proposed a method to precisely detect a movement amount in the 2D direction without using a laser length-measuring instrument and a two-dimensional diffraction grating.

TL;DR: In this article, an encoder includes an electrically conductive reference scale having surface steps formed at predetermined positions, an electric conductive probe having a tip disposed opposed to the reference scale, where the probe is relatively movable in a direction different from the opposing direction of the tip of the probe and the scale.