POSITION MEASURING DEVICE AND POSITION MEASURING METHOD

摘要

A position measuring device includes a light emitter, an image capturer, a first beam splitter, a first light receiver, a second light receiver, a calculator, and a controller. The first light receiver receives light that propagates along a first optical axis toward the light emitter and is reflected by the first beam splitter, and outputs a first signal. The second light receiver outputs a second signal corresponding to an intensity of light propagating along a second optical axis toward the image capturer. The controller controls the intensity of the laser light based on the second signal when a difference between the first signal and the second signal is smaller than a predetermined threshold, and performs control so that the laser light has a predetermined intensity when the difference between the first signal and the second signal is equal to or greater than the threshold.

主权项

1. A position measuring device comprising:
a light emitter configured to emit laser light along a first optical axis for measurement of a position of an object to be measured; an image capturer provided on a second optical axis, the second axis being oblique to the first optical axis; a first beam splitter provided on the first optical axis; a first light receiver configured to receive light that propagates along the first optical axis toward the light emitter and that is reflected by the first beam splitter, the first light receiver further configured to output a first signal corresponding to a light intensity; a second light receiver configured to output a second signal corresponding to an intensity of light propagating along the second optical axis toward the image capturer; a calculator configured to calculate the position of the object to be measured based on the light propagating along the second optical axis; and a controller configured to control an intensity of the laser light based on the second signal when a difference between the first signal and the second signal is smaller than a predetermined threshold, the controller further configured to control the laser light such that the laser light has a predetermined intensity when the difference between the first signal and the second signal is equal to or greater than the threshold.