Display device with coordinate input function

• US 5,465,103 A
• Filed: 09/03/1992
• Issued: 11/07/1995
• Est. Priority Date: 08/28/1989
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yoshioka, Kazuo
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Mengistu, Amare
• Application Number:
  US07/940,397
• Time in Patent Office: 1,160 Days
• Field of Search: 340/706, 340/712, 340/784, 178/18, 178/19, 359/53, 359/103, 359/63, 345/104, 345/173-176, 345/179
• US Class Current: 349/16
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally

Abstract

A display device with coordinate input function with transparent electrodes for inputting coordinates disposed in an X-Y matrix form on an optical phase compensation cell, such as an optically anisotropic phase compensation film, provided for a liquid crystal display panel of two-layer type. Coordinate input can be performed even in the case of a liquid crystal display panel divided into two, upper and lower, separately driven parts to increase the resolution of the display screen, because of the transparent electrodes disposed on the optical phase compensation cell.

Claims

1. A display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates, comprising:

a sensor means for sensing coordinate input detection signals from a control means;

a liquid crystal display panel of two-layer type including an optical phase compensation cell, as a first layer of the liquid crystal display panel and a liquid crystal display cell as a second layer of the liquid crystal display panel; and

a plurality of transparent electrodes arranged on said compensation cell in an X-Y matrix form, for inputting the coordinate input detection signals to said sensor means, wherein said compensation cell is a phase compensation film which exhibits optical anisotropy.

2. The display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates as in claim 1, wherein said optically anisotropic phase compensation film comprises a polycarbonate.

3. The display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates as in claim 1, wherein said optically anisotropic phase compensation film comprises a polyvinyl alcohol.

4. The display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates as in claim 1, wherein said optically anisotropic phase compensation film comprises a polyethylene tetraphthalate.

5. The display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates as in claim 1, wherein said optically anisotropic phase compensation film has a thickness of between about 50 micrometers to about 150 micrometers.

6. The display device with coordinate input function having a liquid crystal display panel for both displaying images and inputting coordinates as in claim 1, wherein said optically anisotropic phase compensation film has a thickness of about 100 micrometers.