Title:
POSITION MEASUREMENT SENSOR, OSCILLATION WAVEFORM OUTPUT DEVICE, KEYBOARD DEVICE, AND METHOD FOR ATTACHING POSITION MEASUREMENT SENSOR
Document Type and Number:
Japanese Patent JP2016148603
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a position measurement sensor with which it is possible to easily linearize the output value of a reflection type photodetector even when this output value changes non-linearly, and an oscillation waveform output device, a keyboard device, and a method for attaching the position measurement sensor.SOLUTION: A position measurement sensor 1 comprises: a first sensor 10 for irradiating the first area of a measurement object with light and outputting a first measured value that corresponds to a first distance from a first reflection type photodetector 11 to the first area on the basis of the amount of reflected light; a second sensor 20 for irradiating the second area of the measurement object with light and outputting a second measured value that corresponds to a second distance from a second reflection type photodetector 21 to the second area on the basis of the amount of reflected light; and a difference calculation unit 30 for outputting a difference value between the first measured value and the second measured value, the first sensor 10 and the second sensor 20 being disposed so that the second distance decreases when the first distance increases due to the movement of the measurement object to the first reflection type photodetector 11 and the second reflection type photodetector 21.SELECTED DRAWING: Figure 1
Inventors:
ISHII JUN
Application Number:
JP2015026032A
Publication Date:
August 18, 2016
Filing Date:
February 13, 2015
Export Citation:
Assignee:
YAMAHA CORP
International Classes:
G01B11/00; G01H9/00; G10H3/14
Attorney, Agent or Firm:
Takahashi Hayashi & Partners