Digitizing apparatus

• US 6,914,595 B1
• Filed: 09/28/2000
• Issued: 07/05/2005
• Est. Priority Date: 09/29/1999
• Status: Expired due to Fees

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Kobayashi, Mitsugu, Uehara, Hisao
• Primary Examiner(s): Eisen, Alexander
• Assistant Examiner(s): NGUYEN, KIMNHUNG T
• Application Number:
  US09/672,943
• Time in Patent Office: 1,741 Days
• Field of Search: 345/173, 345178-183, 345/76, 345/179, 345/77, 345/35, 345/36, 178/18.01, 178/18.03, 178/18.05, 178/18.06
• US Class Current: 345/179
• CPC Class Codes: G06F 3/03542 Light pens for emitting or receiving light
• CPC Class Codes: G06F 3/0386 for light pen
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]

Abstract

Graphics are drawn with an input pen, which is provided with an optical sensor at its tip, on a display surface of an EL display. At this time, the EL display is caused to emit light in dot sequence, and the position of the input pen is detected as coordiante information on the basis of timing of light emission of the EL display and timing of light emission detection of the input pen.

Claims

1. A digitizing apparatus comprising:

an electroluminescence display having a plurality of display pixels disposed in a matrix;

a pen for contacting the display surface of said display and for detecting the emissive state of the display pixel at the position of contact;

a display control circuit for displaying an image on said display by determining timing of horizontal scanning and vertical scanning and for causing said plurality of display pixels to emit light in dot sequence in accordance with the timing of horizontal scanning and vertical scanning;

a digitizing processing circuit for generating coordinate information on the basis of change in detection output of said pen with respect to timing of horizontal scanning and vertical scanning of said display control circuit;

a plurality of display pixels disposed in a matrix and having an emissive layer disposed between a pair of electrodes;

a horizontal driver circuit for sequentially applying a voltage in accordance with image information to each column of said plurality of display pixels at the timing of horizontal scanning;

a vertical driver circuit for driving said plurality of display pixels in row units at the timing of vertical scanning; and

wherein said display control circuit causes said plurality of display pixels to emit light at a predetermined luminance in dot sequence one row at a time during a blanking period of each horizontal scanning period.

2. A digitizing apparatus comprising:

an electroluminescence display having a plurality of display pixels disposed in a matrix;

a pen for contacting the display surface of said display and for detecting the emissive state of the display pixel at the position of contact;

a display control circuit for displaying an image on said display by determining timing of horizontal scanning and vertical scanning and for causing said plurality of display pixels to emit light in dot sequence in accordance with the timing of horizontal scanning and vertical scanning;

a digitizing processing circuit for generating coordinate information on the basis of change in detection output of said pen with respect to timing of horizontal scanning and vertical scanning of said display control circuit;

a plurality of display pixels disposed in a matrix and having an emissive layer disposed between a pair of electrodes;

a horizontal driver circuit for sequentially applying a voltage in accordance with image information to each column of said plurality of display pixels at the timing of horizontal scanning;

a vertical driver circuit for driving said plurality of display pixels in row units at the timing of vertical scanning; and

wherein said display control circuit causes said plurality of display pixels to emit light one row at a time in accordance with image information during a first horizontal scanning period and causes said plurality of display pixels to emit light at a predetermined luminance one row at a time in dot sequence during a second horizontal scanning period.

3. A digitizing apparatus comprising:

an electroluminescence display having a plurality of display pixels disposed in a matrix;

a pen for contacting the display surface of said display and for detecting the emissive state of the display pixel at the position of contact;

a display control circuit for displaying an image on said display by determining timing of horizontal scanning and vertical scanning and for causing said plurality of display pixels to emit light in dot sequence in accordance with the timing of horizontal scanning and vertical scanning;

a digitizing processing circuit for generating coordinate information on the basis of change in detection output of said pen with respect to timing of horizontal scanning and vertical scanning of said display control circuit;

a plurality of display pixels disposed in a matrix and having an emissive layer disposed between a pair of electrodes;

a horizontal driver circuit for sequentially applying a voltage in accordance with image information to each column of said plurality of display pixels at the timing of horizontal scanning;

a vertical driver circuit for driving said plurality of display pixels in row units at the timing of vertical scanning; and

wherein said display control circuit causes said plurality of display pixels to emit light at a predetermined luminance one screen at a time in dot sequence during a blanking period of each vertical scanning period.

4. A digitizing apparatus comprising:

an electroluminescence display having a plurality of display pixels disposed in a matrix;

a pen for contacting the display surface of said display and for detecting the emissive state of the display pixel at the position of contact;

a display control circuit for displaying an image on said display by determining timing of horizontal scanning and vertical scanning and for causing said plurality of display pixels to emit light in dot sequence in accordance with the timing of horizontal scanning and vertical scanning;

a digitizing processing circuit for generating coordinate information on the basis of change in detection output of said pen with respect to timing of horizontal scanning and vertical scanning of said display control circuit;

a plurality of display pixels disposed in a matrix and having an emissive layer disposed between a pair of electrodes;

a horizontal driver circuit for sequentially applying a voltage in accordance with image information to each column of said plurality of display pixels at the timing of horizontal scanning;

a vertical driver circuit for driving said plurality of display pixels in row units at the timing of vertical scanning; and

wherein said display control circuit causes said plurality of display pixels to emit light one screen at a time in accordance with image information during a first vertical scanning period and causes said plurality of display pixels to emit light at a predetermined luminance one screen at a time in dot sequence and during a second vertical scanning period.

5. A digitizing apparatus comprising:

an electroluminescence display having a plurality of display pixels disposed in a matrix;

a pen for contacting the display surface of said display and for detecting the emissive state of the display pixel at the position of contact;

a display control circuit for displaying an image on said display by determining timing of horizontal scanning and vertical scanning and for causing said plurality of display pixels to emit light in dot sequence in accordance with the timing of horizontal scanning and vertical scanning;

a digitizing processing circuit for generating coordinate information on the basis of change in detection output of said pen with respect to timing of horizontal scanning and vertical scanning of said display control circuit;

a plurality of display pixels disposed in a matrix and having an emissive layer disposed between a pair of electrodes;

a horizontal driver circuit for sequentially applying a voltage in accordance with image information to each column of said plurality of display pixels at the timing of horizontal scanning;

a vertical driver circuit for driving said plurality of display pixels in row units at the timing of vertical scanning; and

wherein said display control circuit, when causing said plurality of display pixels to emit light in dot sequence, causes said plurality of display pixels to emit light at a predetermined illuminance after once setting said plurality of display pixels to a non-emissive state.

6. A digitizing apparatus according to claim 5 wherein said electroluminescence display further comprises a pre-charge circuit for supplying a predetermined voltage to said plurality of display pixels, and voltage is supplied from said pre-charge circuit to said plurality of display pixels so as to set each display pixel to a non-emissive state.