Coordinates input apparatus

• US 5,744,760 A
• Filed: 09/04/1996
• Issued: 04/28/1998
• Est. Priority Date: 09/07/1995
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tanaka, Atsushi, Sato, Hajime, Kobayashi, Katsuyuki, Tokioka, Masaki, Yoshimura, Yuichiro, Yanagisawa, Ryozo
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): Miller, Rose M.
• Application Number:
  US08/707,721
• Time in Patent Office: 601 Days
• Field of Search: 178/18, 178/19, 73/597
• US Class Current: 178/19.02
• CPC Class Codes: G06F 3/0433 in which the acoustic waves are either generated by a movable member and propagated within a surface layer or propagated within a surface layer and captured by a movable member

Abstract

It is an object to provide a portable coordinates input apparatus which can be manufactured at low costs. An input pen applies a voltage to a desired position in a coordinate input area on a vibration propagating plate having a piezoelectric performance and having a first surface including the coordinate input area and a second area that faces the first surface. A vibration generated by the voltage is detected as an electric signal by a vibration detecting electrode arranged out of the coordinate input area.

Claims

1. A coordinates input apparatus for inputting coordinates by an input pen, comprising:

a vibration propagating plate which has a piezoelectric performance and has a first surface including a coordinate input area and a second surface that faces said first surface;

applying means for applying a voltage to said vibration propagating plate by making said input pen come into contact with a desired position in said coordinate input area; and

detecting means for detecting a vibration which ms generated by said voltage as an electric signal at a position of an electrode arranged out of said coordinate input area,

wherein said coordinate input area has a mesh-like electrode.

2. An apparatus according to claim 1, further comprising:

first calculating means for calculating a time which is required until the vibration arrives at each of said detecting means;

second calculating means for calculating the position at which said input pen comes into contact on the basis of each time that is calculated by said first calculating means; and

output means for outputting the position that is calculated by said second calculating means.

3. An apparatus according to claim 1, wherein said input pen is connected to the ground.

4. An apparatus according to claim 1, wherein said second surface has at least an electrode of a same size as that of said coordinate input area at a position which faces said coordinate input area.

5. An apparatus according to claim 4, wherein the electrode of said second surface is connected to the ground.

6. An apparatus according to claim 1, wherein said vibration propagating plate is a vibration propagating plate made of piezoelectric ceramics.

7. An apparatus according to claim 1, wherein said vibration propagating plate includes at least any one of PZT, ZnO, PLZT, and PVDF.