Display device with transflective electrode

• US 6,211,992 B1
• Filed: 12/03/1998
• Issued: 04/03/2001
• Est. Priority Date: 12/04/1997
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: Flat Panel Display (FPD) B.V.
• Inventors: Van Aerle, Nicolaas A. J. M., Pitt, Michael G.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): THOMPSON, TIMOTHY J
• Application Number:
  US09/204,177
• Time in Patent Office: 852 Days
• Field of Search: 349/21, 345/22, 345/88
• US Class Current: 359/254
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133621 providing coloured light G02F1/133617, G02F1/133533 take precedence
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 2203/09 transflective

Abstract

A transflective color display having apertures in reflective electrodes through which light from a backlight (9) passes in the transmissive mode. The switching behavior for both the reflective and the transmissive mode is made identical by introducing a retardation plate (11). The transmission efficiency is further increased by using only a monochrome green mode in transmission.

Claims

1. A display device comprising a display panel with a first light-transmitting substrate provided with reflective material, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that at the location of picture elements the reflective material is provided with at least one aperture, in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and in that the apertures are situated at the location of green picture elements.

2. A display device comprising a display panel with a first light-transmitting substrate provided with reflective material, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that at the location of picture elements the reflective material is provided with at least one aperture, in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and in that green picture elements occupy a larger surface area than red or blue picture elements.

3. A display device comprising a display panel with a first light-transmitting substrate provided with reflective material, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that at the location of picture elements the reflective material is provided with at least one aperture, in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and in that a row of green picture elements is situated between rows comprising both red and blue picture elements.

4. A display device comprising a display panel with a first light-transmitting substrate provided with a plurality of picture electrodes arranged according to a pattern, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that said picture electrodes comprise a reflective material, at the location of respective picture elements in said picture electrodes the reflective material is provided with at least one respective aperture, and characterized in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and

the green picture elements occupy a larger surface area than red or blue picture elements.

5. A display device comprising a display panel with a first light-transmitting substrate provided with a plurality of picture electrodes arranged according to a pattern, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that said picture electrodes comprise a reflective material, at the location of respective picture elements in said picture electrodes the reflective material is provided with at least one respective aperture, and characterized in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and

a row of green picture elements is situated between rows comprising both red and blue picture elements.

6. A display device comprising a display panel with a first light-transmitting substrate provided with a picture electrode comprising reflective material, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that at the location of respective picture elements in said picture electrode the reflective material is provided with a respective aperture defining the respective picture element and characterized in that the display device is provided, on the side of the first substrate, with a light source emitting green light and

the green picture elements occupy a larger surface area than red or blue picture elements.

7. A display device comprising a display panel with a first light-transmitting substrate provided with a picture electrode comprising reflective material, a second light-transmitting substrate and an electro-optical material between said two substrates, characterized in that at the location of respective picture elements in said picture electrode the reflective material is provided with a respective aperture defining the respective picture element, and characterized in that the display device is provided, on the side of the first substrate, with a light source emitting green light, and a row of green picture elements is situated between rows comprising both red and blue picture elements.