The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 09, 2007
Filed:
Jan. 04, 2005
Tomoyuki Ura, Shizuoka-ken, JP;
Tsutomu Sasaki, Shizuoka-ken, JP;
Yasuhiko Ohba, Shizuoka-ken, JP;
Masahisa Hashimoto, Shizuoka-ken, JP;
Tomoyuki Ura, Shizuoka-ken, JP;
Tsutomu Sasaki, Shizuoka-ken, JP;
Yasuhiko Ohba, Shizuoka-ken, JP;
Masahisa Hashimoto, Shizuoka-ken, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
Keys, which are incorporated in an automatic player piano, are monitored with an optical transducer system. The optical transducer system includes sensor heads provided on both sides of the key trajectories, LEDs connected to predetermined sensor heads through optical fibers, LDDs connected to the other sensor heads through optical fibers and a controlling unit. A luminescence controller is connected to the LEDs for optimizing the luminescence, and bias controllers are respectively connected to the LDDs. The luminescence controller and bias controllers optimize the luminescence of emitted light and the bias level of electric signals so that the optical transducer system is free from the individuality of component parts and the deterioration.