Coordinate input apparatus

• US 5,500,492 A
• Filed: 10/24/1994
• Issued: 03/19/1996
• Est. Priority Date: 11/27/1991
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Tanaka, Atsushi, Kobayashi, Katsuyuki, Tokioka, Masaki, Yoshimura, Yuichiro, Yanagisawa, Ryozo, Kaneko, Kiyoshi, Taniishi, Shinnosuke
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): LOOMIS, PAUL A
• Application Number:
  US08/327,806
• Time in Patent Office: 512 Days
• Field of Search: 178/18, 178/19, 178/20, 345/177, 366/908, 364/709.11
• US Class Current: 178/18.04
• 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

Disclosed is a coordinate input apparatus for detecting an input vibration from a vibration pen by a vibration sensor provided on a vibration transmitting plate to measure a vibration transmission time to the vibration pen to detect the input coordinates of the vibration pen on the vibration transmitting plate on the basis of the measurement result. The vibration pen is made wireless by incorporating all mechanisms required to generate the vibration. A drive timing for vibration input from the vibration pen and used as a measurement origin of the vibration transmission time is transmitted to a main body for performing the coordinate detection processing by bringing the vibration pen in temporary contact with the main body.

Claims

1. A coordinate input apparatus for detecting vibration inputted from vibration input means by using vibration detecting means provided on a vibration transmitting member to measure a vibration transmission time to said vibration input means to detect input coordinates of said vibration input means on said vibration transmitting member on the basis of a result of the measuring, comprising:

holding means for causing said vibration input means to contact a predetermined position; and

means for synchronizing a vibration generating timing of said vibration input means and a measuring start timing of a counter for measuring time when the vibration input means is secured on the predetermined position.

2. An apparatus according to claim 1, wherein said holding means includes placing means for placing the vibration input means and provided in an apparatus main body.

3. A coordinate input apparatus for detecting vibration inputted from vibration input means by using vibration detecting means provided on a vibration transmitting member to measure a vibration transmission time to said vibration input means to derive coordinates at a constant period on the basis of a result of the measuring, said apparatus comprising:

detecting means provided in said vibration input means for detecting input of information except the coordinates; and

driving means for outputting vibration representing a condition of said detecting means at a period during vibration outputting for deriving the coordinates and vibration outputting for deriving the coordinates at a next period.

4. A coordinate input apparatus for detecting an input vibration from vibration input means by using vibration detecting means provided on a vibration transmitting member to detect coordinates of said vibration input means on the vibration transmitting member, comprising:

first frequency extracting means for extracting a specified frequency component from a detection signal waveshape detected by the vibration detecting means;

second frequency extracting means for extracting a frequency component different from the frequency extracted by said first frequency extracting means;

time measuring means for measuring a difference of arrival delay time between waveshapes each obtained by said first and second frequency extracting means from the waveshapes; and

means for calculating a distance from the vibration detecting means to a vibrating input point of the vibration input means, from a transmission velocity of each waveshape on the vibration transmitting member and the time obtained by the time measuring means to detect a position of said vibration input means on the basis of said distance.

5. A coordinate input apparatus in which a plurality of vibration sensors are arranged on a coordinate input surface on which a vibration propagates to measure distances from coordinate designating means for generating a vibration to said each vibration sensor in accordance with time of arrival of the vibration to calculate a point designated on said coordinate input surface by said coordinate designating means as a coordinate value, comprising:

means for measuring a delay time concerning a phase velocity of a vibration of a first frequency propagating on said coordinate input surface;

means for measuring a delay time concerning a group velocity of a vibration of a second frequency higher than the first frequency, propagating on said coordinate input surface; and

means for obtaining a coordinate position of said coordinate designating means on the basis of the measured group velocity delay time and the measured phase velocity delay time.

6. An apparatus according to claim 5, wherein said coordinate designating means includes vibration generating means to be driven alternately by the first and second frequencies at a predetermined period.

7. An apparatus according to claim 5, further comprising a first bandpass filter using the first frequency as a center frequency and a second bandpass filter using the second frequency as a center frequency, and

wherein said vibration designating means generates a vibration with a band width covering the first and second frequencies, said first bandpass filter extracts a vibration of the first frequency from the output signal from said vibration sensor, and said second bandpass filter extracts a vibration of the second frequency therefrom.