Patent ID: 11959735
Assignee: HITACHI HIGH-TECHNOLOGIES CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A height measuring device, comprising:
a projection optical system configured to project a light ray onto an object to be measured;
a detection optical system including a detection element configured to detect a reflected light ray from the object to be measured;
a processing device configured to measure a height of the object to be measured based on an output of the detection element;
an adjustment element disposed lengthwise along a projection direction of the light ray projected by the projection optical system and between the projection optical system and the object to be measured, and including a smooth flat light incident surface and a smooth flat light emission surface which are parallel to each other; and
a correction element disposed lengthwise along a direction of the reflected light ray reflected from the object to be measured and between the object to be measured and the detection optical system, and including a smooth flat light incident surface and a smooth flat light emission surface which are parallel to each other, wherein
a length of the adjustment element is longer than a length of the correction element,
the projection optical system includes a light splitting element which splits a trajectory of the light ray with which the object to be measured is irradiated into a plurality of parts, and
the detection optical system includes a double-sided wedge substrate configured to focus a plurality of trajectories of the light ray into one point on the detection element, the double-sided wedge substrate including a first surface through which a first trajectory of the light ray is transmitted and a second surface, different from the first surface, through which a second trajectory, different from the first trajectory, of the light ray is transmitted.