JPS5456327A - Page detecting system - Google Patents

Page detecting system

Info

Publication number
JPS5456327A
JPS5456327A JP12250277A JP12250277A JPS5456327A JP S5456327 A JPS5456327 A JP S5456327A JP 12250277 A JP12250277 A JP 12250277A JP 12250277 A JP12250277 A JP 12250277A JP S5456327 A JPS5456327 A JP S5456327A
Authority
JP
Japan
Prior art keywords
frequency
light
tablet
converted
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP12250277A
Other languages
Japanese (ja)
Inventor
Yutaka Kamiyama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP12250277A priority Critical patent/JPS5456327A/en
Publication of JPS5456327A publication Critical patent/JPS5456327A/en
Pending legal-status Critical Current

Links

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  • Input From Keyboards Or The Like (AREA)

Abstract

PURPOSE: To ensure an assured page detection for the tablet with no effect by the external light, by detecting the light emitted from the light emission part where the light corresponding to the fixed frequency is generated and then converting the light into the electric signal to amplify the fixed amount of frequency.
CONSTITUTION: Oscillator 21 always oscillates frequency f1Hz (to be set to 450HzW 455K Hz to avoid the higher harmonic wave of the ceiling lamp), and the output is converted (22) to optical signal 24 to reach light receiving part 23 after amplification 26. At the same time, external light 25 arrives at part 23, and the output is amplified (26) and then converted (27) to make tablet device 1 perform the page detection for tablet 2. Characteristics 50 resonated with frequency f1 is provided to amplifier 26, and the gain is set large near frequency f1 and set small at the place away from f1, thus only the desired signal being extracted. Thus, the misdetection caused by the too bright periphery of device 1 can be prevented
COPYRIGHT: (C)1979,JPO&Japio
JP12250277A 1977-10-14 1977-10-14 Page detecting system Pending JPS5456327A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12250277A JPS5456327A (en) 1977-10-14 1977-10-14 Page detecting system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12250277A JPS5456327A (en) 1977-10-14 1977-10-14 Page detecting system

Publications (1)

Publication Number Publication Date
JPS5456327A true JPS5456327A (en) 1979-05-07

Family

ID=14837423

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12250277A Pending JPS5456327A (en) 1977-10-14 1977-10-14 Page detecting system

Country Status (1)

Country Link
JP (1) JPS5456327A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4973960A (en) * 1989-02-24 1990-11-27 Amoco Corporation Data entry method and apparatus

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4930375A (en) * 1970-06-23 1974-03-18
JPS4930735A (en) * 1972-07-24 1974-03-19
JPS5215230A (en) * 1975-07-28 1977-02-04 Nec Corp Data making unit

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4930375A (en) * 1970-06-23 1974-03-18
JPS4930735A (en) * 1972-07-24 1974-03-19
JPS5215230A (en) * 1975-07-28 1977-02-04 Nec Corp Data making unit

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4973960A (en) * 1989-02-24 1990-11-27 Amoco Corporation Data entry method and apparatus

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