Dot matrix type multi-layer liquid crystal display device

• US 4,449,123 A
• Filed: 12/01/1980
• Issued: 05/15/1984
• Est. Priority Date: 12/14/1979
• Status: Expired due to Term

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: Muranaga, Yoshinobu
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/211,745
• Time in Patent Office: 1,261 Days
• Field of Search: 340/716, 340/784, 340/728, 340/765, 178/30, 350/330, 350/331, 350/332, 350/333, 350/334, 350/335
• US Class Current: 345/4
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
• CPC Class Codes: G09G 3/18 using liquid crystals

Abstract

A dot matrix type multi-layered liquid crystal display device has at least two liquid crystal display sections. Each liquid crystal display section has a dot matrix of transparent electrodes, and the individual liquid crystal display sections are arranged in layers such that their respective dot matrices of transparent electrodes overlie one another.

Claims

1. A dot matrix type multi-layer liquid crystal display device comprising:

a liquid crystal display unit including at least two liquid crystal display sections, each liquid crystal display section including a liquid crystal sandwiched between two transparent base plates, and transparent electrodes arranged in the form of a dot matrix pattern, said transparent electrodes being provided on a transparent base plate, said dot matrix patterns of each liquid crystal display section having a plurality of rows and columns of dots, said rows and columns extending horizontally and vertically, respectively, in the plane of the respective display section;

means for arranging said liquid crystal display sections one above another such that the transparent electrodes of one liquid crystal display section are disposed without overlapping the transparent electrodes of the other liquid crystal display section when viewing in the vertical diection with respect to said transparent base plates, and said transparent electrodes of said one liquid display section projecting into the horizontal and vertical interstices between the transparent electrodes of the other liquid crystal display section when viewing in the horizontal direction with respect to said transparent base plates;

means for supplying a common drive signal to the transparent electrodes of one of said crystal display sections; and

at least two decoding means coupled respectively to the liquid crystal display sections, said decoding means each decoding input data representing a character, a numeral of a symbol in synchronism with said common drive signal and supplying segment drive signals to the transparent electrodes of the respective liquid crystal display sections.

2. A dot matrix type multi-layer liquid crystal display device according to claim 1, wherein adjacent liquid crystal display sections of said liquid crystal display unit include a common transparent base plate, said common base plate constituting both the lower transparent base plate of an upper liquid crystal display means and the upper transparent base plate of a lower liquid crystal display means.

3. A dot matrix type multi-layer liquid crystal display device according to claim 2, wherein transparent electrodes in the form of dot matrices are provided on both sides of said common transparent base plate such that the transparent electrodes on the upper side thereof do not coincide with the transparent electrodes on the lower side thereof.

4. A dot matrix type multi-layer liquid crystal display device according to claim 1, wherein said liquid crystal display unit includes a liquid crystal display section having a 7-bit dot matrix and another liquid crystal display section having a 6-bit dot matrix.

5. A dot matrix type multi-layer liquid crystal display device according to claim 1, wherein each of said liquid crystal display sections has common terminals for the individual transparent electrode columns of said dot matrix, said common terminals being provided along alternate upper and lower edges of said liquid crystal display section.

6. A dot matrix type multi-layer liquid crystal display device according to claim 1, further comprising means for simultaneously driving all of said liquid crystal display sections.

7. A dot matrix type multi-layer liquid crystal display device according to claim 1, wherein said transparent electrodes are disc-shaped.

8. A dot matrix type multi-layer liquid crystal display device comprising:

a liquid crystal display unit including first and second liquid crystal display means (13a, 13b) each having a liquid crystal (13₂, 13₄) sandwiched between two transparent base plates (13₁, 13₃ and 13₃, 13₅), transparent electrodes (19₁ -19₁₆, 20₁ -20₁₆) arranged in the form of a dot matrix and provided between the transparent base plates (13₁, 13₃ and 13₃, and 13₅), the spacing between the respective transparent electrodes (19₁ -19₁₆) in a first (13a) of said liquid crystal display means (13a, 13b) being less than the maximum width of the respective dots of the transparent electrodes (19₁ -19₁₆), the second liquid crystal display means (13b) being in an overlapping relation to the first liquid crystal display means (13a), and said transparent electrodes (20₁ to 20₁₆) in the second liquid crystal display means (13b) being arranged between the respective transparent electrodes (19₁ -19₁₆) of the first liquid crystal display means (13a) such that they are in a non-overlapping relation to the transparent electrodes (19₁ -19₁₆) of the first liquid crystal display means (13a);

means (12) for supplying common signals to the transparent electrodes (19₁ -19₁₆ and 20₁ -20₁₆) in the first and second liquid crystal display means (13a, 13b); and

at least two decoding means (14,

     15) provided respectively for the first and second liquid crystal display means (13a, 13b), said decoding means (14,

     15) decoding input data representing one character, a numeral or a symbol in synchronism with the common signals and supplying segment signals to the transparent electrodes of the first and second liquid crystal display means (13a, 13b).