Display device and information terminal device

• US 7,522,149 B2
• Filed: 03/29/2004
• Issued: 04/21/2009
• Est. Priority Date: 03/31/2003
• Status: Expired due to Fees

• Current Assignee: Japan Display Central Incorporated (Japan Display Incorporated)
• Original Assignee: Toshiba Matsushita Display Technology (Japan Display Incorporated)
• Inventors: Tanaka, Yasuharu, Nakamura, Takashi, Yoshida, Masahiro, Hayashi, Hirotaka, Ishikawa, Miyuki
• Primary Examiner(s): TRAN, MY CHAU T
• Application Number:
  US10/551,521
• Publication Number:
  US 20060192766A1
• Time in Patent Office: 1,849 Days
• Field of Search: 345/55, 345/84, 345/87, 345/104, 345/156, 345/173, 345/174, 345/175, 345/179, 178/18.01, 178/18.03, 178/18.05, 178/18.06, 178/18.07, 178/18.11
• US Class Current: 345/104
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A liquid crystal display apparatus according to the present invention includes a pixel array unit 1 having signal lines and scanning lines respectively arranged side by side, a signal line drive circuit 2 which drives the signal lines, a scanning line drive circuit 3 which drives the scanning lines, a signal processing output circuit 4 which serially outputs the picked-up image data supplied from the sensors, and a sync signal generation circuit 5. A black-white change obtained in the picked-up image data when a finger is brought close to or brought into contact with the pixel array unit 1 is detected, and the coordinate position of the finger is identified taking the ambient brightness into consideration. Regardless of whether the surroundings are bright or dark, therefore, the coordinate position can be detected with high precision. Furthermore, when conducting the coordinate detection, the picked-up image data corresponding to all pixels are not detected, but the picked-up image data are detected every a plurality of pixels in both the signal line direction and the scanning line direction. Therefore, the time taken to detect the coordinates can be shortened.

Claims

1. A display apparatus capable of detecting that an arbitrary place of a display screen has been pointed by a human hand or a pointing member, the display apparatus comprising:

display elements formed near intersections of signal lines and scanning lines respectively arranged in vertical and horizontal directions;

image pickup units which pick up incident light in a predetermined range;

D/A conversation circuits provided every a plurality of signal lines to supply pixel data for display to a plurality of signal lines associated therewith;

amplifier circuits which output the picked-up image data in the image pickup units from pixels by using signal lines that are not supplied with pixel data, while the D/A conversion circuits supply pixel data to signal lines in order; and

a pointer detection portion which detects a position pointed by a hand or a pointing member on the display screen, on the basis of the picked-up image data,

wherein whenever the image pickup units perform image pickup, the pointer detection portion detects an image that indicates a pointed position, and when a diameter of the image is maximized, the pointer detection portion judges that the display screen has been pressed strongly by a hand or a pointing member.

2. A display apparatus capable of detecting that an arbitrary place of a display screen has been pointed by a human hand or a pointing member, the display apparatus comprising:

display elements formed near intersections of signal lines and scanning lines respectively arranged in vertical and horizontal directions;

image pickup units which pick up incident light in a predetermined range;

D/A conversation circuits provided every a plurality of signal lines to supply pixel data for display to a plurality of signal lines associated therewith;

amplifier circuits which output the picked-up image data in the image pickup units from pixels by using signal lines that are not supplied with pixel data, while the D/A conversion circuits supply pixel data to signal lines in order; and

a pointer detection portion which detects a position pointed by a hand or a pointing member on the display screen, on the basis of the picked-up image data,

wherein the pointer detection portion performs a plurality of product sum computations for successively adding image data of every scanning line, and a division computation conducted using a result of the product sum computations as a numerator or a denominator.

3. The display apparatus according to claim 2, comprising:

a first computation circuit formed on the substrate on which the display elements are formed to conduct the product sum computations; and

a second computation circuit formed on a semiconductor substrate different from the substrate on which the display elements are formed to conduct the division computation.

4. A display apparatus capable of detecting that an arbitrary place of a display screen has been pointed by a human hand or a pointing member, the display apparatus comprising:

display elements formed near intersections of signal lines and scanning lines respectively arranged in vertical and horizontal directions;

image pickup units which pick up incident light in a predetermined range;

D/A conversation circuits provided every a plurality of signal lines to supply pixel data for display to a plurality of signal lines associated therewith;

amplifier circuits which output the picked-up image data in the image pickup units from pixels by using signal lines that are not supplied with pixel data, while the D/A conversion circuits supply pixel data to signal lines in order; and

a pointer detection portion which detects a position pointed by a hand or a pointing member on the display screen, on the basis of the picked-up image data, wherein

denoting the number of pixels in a signal line direction of the display screen by X, the number of pixels in a scanning line direction by Y, and the picked-up image data in an arbitrary pixel (x, y) (where 0≦

x≦

X and 0≦

y≦

Y) by L(x, y),

the pointer detection portion obtains central coordinates (Ex, Ey) of the hand or pointing member using expression (17), and obtains widths (Vx, Vy) of the hand or pointing member in the x direction and y direction using expression (18).

5. The display apparatus according to claim 4, wherein the picked-up image data is a picked-up image subjected to image processing.