Flat panel display wtih external integral heater
View Patent ↗A flat panel display has an optically-transparent electrically-conductive layer, especially an indium tin oxide layer, directly formed on an outer front surface of a liquid crystal display (LCD) assembly having a front plate, a rear plate, and a layer of liquid crystal material interposed between said front and rear plates. The optically-transparent electrically-conductive layer is preferably uniform and functions as an integral heater when connected to a direct current power source.
1. A flat panel display comprising:
a liquid crystal display (LCD) assembly comprising a front plate, rear plate, a layer of liquid crystal material interposed between the front and rear plates, and a thin film transistor (TFT) array interposed between the front and rear plates; a rear polarizer placed below the rear plate of the LCD; and a
a first layer of index-matching dielectric material formed on a face of the front plate opposite the liquid crystal material;
an electrically-conductive optically-transparent layer formed directly atop the first layer of index-matching dielectric material;
means for driving the electrically-conductive optically-transparent layer as a heater, said means in electrical communication with the electrically-conductive optically-transparent layer; and
a second layer of index-matching dielectric material formed directly atop the electrically-conductive optically-transparent layer and; a front polarizer place atop the second layer of index-matching dielectric material.
2. The display of claim 1 wherein:
the electrically-conductive optically-transparent layer operates as an EMI shield for the LCD.
3. The display of claim 1 further comprising:
an electrical ground in electrical connection with the means for driving the electrically-conductive optically-transparent layer as a heater.
4. The display of claim 3 further comprising:
a capacitor in electrical communication between the means for driving the electrically-conductive optically-transparent layer as a heater and the electrical ground.
5. The display of claim 1 further comprising:
a layer of pressure sensitive adhesive (PSA) between the front polarizer and the second layer of index-matching dielectric material.
6. The display of claim 5 further comprising:
a layer of pressure sensitive adhesive (PSA) between the rear polarizer and the rear plate of the LCD.
7. The display of claim 1 wherein:
the electrically-conductive optically-transparent layer has a non-uniform thickness.
8. The display of claim 1 wherein:
the electrically-conductive optically-transparent layer has a constant resistance value between 15 and 20 ohms/sq.
9. A flat panel display comprising:
a liquid crystal display (LCD) assembly comprising a front color plate, a rear plate, a layer of liquid crystal material interposed between the front color plate and rear plate, and a thin film transistor (TFT) array interposed between the front color plate and rear plate;
a rear polarizer placed below the rear plate of the LCD;
a first layer of index-matching dielectric material formed on a face of the front color plate opposite the liquid crystal material;
an electrically-conductive optically-transparent layer formed directly atop the first layer of index-matching dielectric material;
means for driving the electrically-conductive optically-transparent layer as a heater, said means in electrical communication with the electrically-conductive optically-transparent layer;
a second layer of index-matching dielectric material formed directly atop the electrically-conductive optically-transparent layer; and
a front polarizer placed atop the second layer of index-matching dielectric material.
10. The display of claim 9 further comprising:
an anti-reflective coating applied to the top surface of the front polarizer.
11. The display of claim 9 further comprising:
an electrical ground in electrical connection with the means for driving the electrically-conductive optically-transparent layer as a heater.
12. The display of claim 11 further comprising:
a capacitor in electrical communication between the electrically-conductive optically-transparent layer and the electrical ground.
13. The display of claim 9 further comprising:
a layer of pressure sensitive adhesive (PSA) between the front polarizer and the second layer of index-matching dielectric material.
14. The display of claim 13 further comprising:
a layer of pressure sensitive adhesive (PSA) between the rear polarizer and the rear plate of the LCD.
15. The display of claim 9 wherein:
the electrically-conductive optically-transparent layer has a non-uniform thickness.
16. The display of claim 9 wherein:
the electrically-conductive optically-transparent layer has a constant resistance value between 15 and 20 ohms/sq.
17. A device for heating a liquid crystal display (LCD) having a front plate, the heating device comprising:
a first layer of index-matching dielectric material formed on a face of the front plate opposite the liquid crystal material;
an electrically-conductive optically-transparent layer formed directly atop the first layer of index-matching dielectric material; and
a second layer of index-matching dielectric material formed directly atop the electrically-conductive optically-transparent layer.
18. The LCD heating device of claim 17 wherein:
the electrically-conductive optically-transparent layer has a constant resistance value between 15 and 20 ohms/sq.
19. The LCD heating device of claim 17 wherein:
the electrically-conductive optically-transparent layer has a non-uniform thickness.