EP0169538A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Tablet type coordinate input apparatus using elastic waves
Assignee: Hitachi Ltd
•
Filing: 1985-07-23
•
Granted: —
•
Expires: 2005-07-23
Abstract
Abstract A tablet type coordinate input apparatus comprises a flat medium (1) for propagating a longitudinal elastic wave, longitudinal elastic wave detecting elements (2a - 2d) disposed on part of the end-adjacent side surfaces or of the front surface of the flat medium, a longitudinal elastic wave input member (3) having an end portion (10) terminating in a sharp-pointed end (12) and brought into pressure engagement at that end with any disired position on the surface of the flat medium to radiate the longitudinal elastic wave from that end, an amplifier circuit (5a) amplifying electrical signals indicative of the elastic wave detected by the detecting elements, a comparator circuit (5b) comparing the signals amplified by the amplifier circuit with a predetermined threshold voltage thereby generating delay pulse signals corresponding to the propagation times of the longitudinal elastic wave, a counter circuit (6) counting the lengths of time elapsed from the time of radiation of the longitudinal elastic wave toward the flat medium as a result of pressure engagement of the input member therewith to the time of generation of the delay pulse signals, and a computing circuit (7) computing the coordinates on the basis of the time signals applied from the counter circuit.
Inventors
- 👤 Ichiya Sato
- 👤 Takao Yoneyama
- 👤 Masanori Tanabe
- 👤 Kanji Kawakami
- 👤 Hisao Okada
- 👤 Soji Sasaki
- 👤 Shigeru Inose
- 👤 Mareo Suto
- 👤 Hideo Uzuhashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 18:38
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/043; G06F3/0433
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
90 words
A tablet type coordinate input apparatus using an elastic wave, comprising: medium means (1) for propagating an elastic wave; elastic wave detecting means (2) disposed at least part of said medium means; elastic wave input means (3) for radiating the elastic wave toward any desired position on the surface of said medium means; and means (5, 6, 7) receiving electrical signals indicative of a longitudinal elastic wave component of said radiated elastic wave detected by said detecting means, thereby providing coordinate information of the- input position of said input means.
Claim 2
Dependent Claim
90 words
A tablet type coordinate input apparatus using an elastic wave, comprising: medium means (1) for propagating an elastic wave; elastic wave detecting means (2) disposed at least part of said medium means; elastic wave input means (3) for radiating the elastic wave toward any desired position on the surface of said medium means; and means (5, 6, 7) receiving electrical signals indicative of a longitudinal elastic wave component of said radiated elastic wave detected by said detecting means, thereby providing coordinate information of the- input position of said input means.
Claim 3
Dependent Claim
142 words
A tablet type coordinate input apparatus, comprising: flat medium means (1) for propagating an elastic wave; detecting means (2) disposed on part of the end-adjacent side surfaces or of the front surface of said medium means for detecting a leading wave of a longitudinal elastic wave component of said elastic wave; elastic wave input means (3) having an end portion (10) terminating in a sharp-pointed end (12) and brought into pressure engagement at said end with any desired position on the front surface of said medium means to radiate the elastic wave from said end; and means (5, 6, 7) for receiving electrical signals indicative of the leading wave of the longitudinal elastic wave detected by said detecting means (2) as a result of radiation of said elastic wave, thereby providing information of the identified engaging position of said input means (3).
Claim 4
Dependent Claim
142 words
A tablet type coordinate input apparatus, comprising: flat medium means (1) for propagating an elastic wave; detecting means (2) disposed on part of the end-adjacent side surfaces or of the front surface of said medium means for detecting a leading wave of a longitudinal elastic wave component of said elastic wave; elastic wave input means (3) having an end portion (10) terminating in a sharp-pointed end (12) and brought into pressure engagement at said end with any desired position on the front surface of said medium means to radiate the elastic wave from said end; and means (5, 6, 7) for receiving electrical signals indicative of the leading wave of the longitudinal elastic wave detected by said detecting means (2) as a result of radiation of said elastic wave, thereby providing information of the identified engaging position of said input means (3).
Claim 5
Dependent Claim
65 words
A tablet type coordinate input apparatus as claimed in Claim 2, wherein said detecting means (2) are disposed at the corners of the side surfaces of said flat medium means (1), and said end portion (10) of said elastic wave input means (3) is made of a material having an acoustic impedance substantially equal to that of the material forming said flat medium means (1).
Claim 6
Dependent Claim
117 words
A tablet type coordinate input apparatus as claimed in Claim 2 or 3, wherein said elastic wave input means (3) is in the form of a wave-guide rod of axial symmetry, one end (12) of which is sharp-pointed to be freely brought into pressure engagement with any desired position on the surface of said flat medium means (1), while the other end of which has a planar surface (3d) perpendicular to the symmetrical axis of said wave-guide rod to support a transmitting piezoelectric element (3b) thereon, and said detecting means (2) disposed on part of the end-adjacent side surfaces or of the front surface of said flat medium means (1) include receiving piezoelectric elements (2a - 2d).
Claim 7
Dependent Claim
171 words
A tablet type coordinate input apparatus as claimed in Claim 2 or 3, whrerein said means for receiving the electrical signals indicative of the leading wave of the longitudinal elastic wave detected by said detecting means (2) as a result of radiation of said elastic wave, thereby providing the information of the identified engaging position of said input means (3) includes an amplifier circuit (5a) amplifying said electrical signals, a comparator circuit (5b) comparing said signals amplified by said amplifier circuit with a predetermined threshold voltage thereby generating delay pulse signals corresponding respectively to the propagation times of said longitudinal elastic wave, a counter circuit (6) counting the lengths of time elasped from the time of radiation of said longitudinal elastic wave toward said flat medium means (1) as a result of pressure engagement of said input means (3) therewith to the time of generation of said delay pulse signals, and a computing circuit (7) computing the coordinates on the basis of the time signals applied from said counter circuit (6).
Claim 8
Dependent Claim
117 words
A tablet type coordinate input apparatus as claimed in Claim 4, wherein said receiving piezoelectric elements (2a - 2d) are fixed at their surface perpendicular to the direction of polarization to the side surfaces of said planar medium means (1), while said transmitting piezoelectric element (3b) is fixed at its surface perpendicular to the direction of polarization to said planar surface (3d) of said wave-guide rod (3), and the resonance frequency of said transmitting element (3b) in the direction perpendicular to the direction of polarization is selected to be substantially equal or close to that of said receiving piezoelectric elements (2a - 2d) in the direction of polarization or the direction perpendicular to the direction of polarization.
Claim 9
Dependent Claim
108 words
A tablet type coordinate input apparatus as claimed in Claim 4, wherein said receiving piezoelectric elements (2a - 2d) are fixed at their surface perpendicular to the direction of polarization to the front surface of said flat medium means (1), while said transmitting piezoelectric element (3b) is fixed at its surface perpendicular to the direction of polarization to said planar surface (3d) of said wave-guide rod (3), and the resonance frequency of said transmitting piezoelectric element in the direction perpendicular to the direction of polarization is selected to be equal or close to that of said receiving piezoelectric elements in the direction perpendicular to the direction of polarization.
Claim 10
Dependent Claim
47 words
A tablet type coordinate input apparatus as claimed in Claim 4, 6 or 7, wherein said transmitting piezoelectric element (3b) and said receiving piezoelectric elements (2a - 2d) have different resonance frequencies in the direction of polarization and the direction perpendicular to the direction of polarization respectively.
Claim 11
Dependent Claim
164 words
A tablet type coordinate input apparatus comprising input means (3) having a built-in ultrasonic wave transmitting element generating an ultrasonic wave by being excited by an electrical signal and having a sharp-pointed end (12) for radiating the ultrasonic wave, writable means (1) for propagating the ultrasonic wave radiated from said input means, detecting means including wave receiving elements (2a - 2d) disposed at or adjacent to the corners of said writable means for converting the propagating ultrasonic wave into electrical signals, and signal processing means (5, 6, 7) for identifying the position of said input means by processing the output signals of said detecting means, said writable means (1) being composed of at least two laminar media including a laminar propagation medium (la) propagating the ultrasonic wave and an overlying laminar input medium (lb) having a longitudinal wave propagation velocity lower than that of said laminar propagation medium (la), said wave receiving elements (2a - 2d) being mounted to said laminar propagation medium (la).
Claim 12
Dependent Claim
164 words
A tablet type coordinate input apparatus comprising input means (3) having a built-in ultrasonic wave transmitting element generating an ultrasonic wave by being excited by an electrical signal and having a sharp-pointed end (12) for radiating the ultrasonic wave, writable means (1) for propagating the ultrasonic wave radiated from said input means, detecting means including wave receiving elements (2a - 2d) disposed at or adjacent to the corners of said writable means for converting the propagating ultrasonic wave into electrical signals, and signal processing means (5, 6, 7) for identifying the position of said input means by processing the output signals of said detecting means, said writable means (1) being composed of at least two laminar media including a laminar propagation medium (la) propagating the ultrasonic wave and an overlying laminar input medium (lb) having a longitudinal wave propagation velocity lower than that of said laminar propagation medium (la), said wave receiving elements (2a - 2d) being mounted to said laminar propagation medium (la).
Claim 13
Dependent Claim
58 words
A tablet type coordinate input apparatus as claimed in Claim 9, wherein an intermediate laminar medium (lc) is interposed between said laminar propagation medium (la) and said laminar input medium (lb) constituting said writable means (1) and has a longitudinal wave propagation velocity intermediate between that of said laminar propagation medium and that of said laminar input medium.
Claim 14
Dependent Claim
116 words
A tablet type coordinate input apparatus comprising input means (3) having a built-in ultrasonic wave transmitting element generating an ultrasonic wave by being excited by an electrical signal and having a sharp-pointed end (12) for radiating the ultrasonic wave, writable means (1) for propagating the ultrasonic wave radiated from said input means, detecting means including wave receiving elements (2a - 2d) disposed at or adjacent to the corners of said writable means for converting the propagating ultrasonic wave into electrical signals, signal processing means (5, 6, 7) for identifying the position of said input means by processing the output signals of said detecting means, and display means (15) for displaying the identified position, said input means
Claim 15
Dependent Claim
116 words
A tablet type coordinate input apparatus comprising input means (3) having a built-in ultrasonic wave transmitting element generating an ultrasonic wave by being excited by an electrical signal and having a sharp-pointed end (12) for radiating the ultrasonic wave, writable means (1) for propagating the ultrasonic wave radiated from said input means, detecting means including wave receiving elements (2a - 2d) disposed at or adjacent to the corners of said writable means for converting the propagating ultrasonic wave into electrical signals, signal processing means (5, 6, 7) for identifying the position of said input means by processing the output signals of said detecting means, and display means (15) for displaying the identified position, said input means
Claim 16
Dependent Claim
32 words
(3) being provided at its sharp-pointed end (12) with a contact-purpose small piece (12a) formed of a medium whose longitudinal wave propagation velocity is lower than that of said writable means (1).
Claim 17
Dependent Claim
32 words
(3) being provided at its sharp-pointed end (12) with a contact-purpose small piece (12a) formed of a medium whose longitudinal wave propagation velocity is lower than that of said writable means (1).
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.