CN1176397C

CN1176397C - Liquid crystal display

Info

Publication number: CN1176397C
Application number: CNB02126211XA
Authority: CN
Inventors: 石储荣; 陈志宏; 陆一民
Original assignee: Toppoly Optoelectronics Corp
Current assignee: TPO Displays Corp
Priority date: 2002-07-15
Filing date: 2002-07-15
Publication date: 2004-11-17
Anticipated expiration: 2022-07-15
Also published as: CN1395137A

Abstract

The present invention relates to a liquid crystal display which comprises a liquid crystal layer, a reflection pixel electrode, a transmission electrode and a protective layer of a transmission conductor, wherein the liquid crystal layer comprises a plurality of liquid crystal molecules, the transmission electrode and the reflection pixel electrode are respectively arranged on both sides of the liquid crystal layer, and the array direction of the liquid crystal molecules in the liquid crystal layer can be controlled by a voltage difference applied to the reflection pixel electrode and the transmission electrode. The protective layer of a transmission conductor is arranged between the liquid crystal layer and the reflection pixel electrode and is covered at the surface of the reflection pixel electrode to prevent the reflectivity drop of the reflection pixel electrode.

Description

LCD

Technical field

The present invention is a kind of LCD, refers to a kind of reflective liquid-crystal display especially.

Background technology

And even on portable electronic devices such as electronic watch, counter, PDA(Personal Digital Assistant) mobile phone handsets, mostly with LCD (Liquid Crystal Display, LCD) finish its display device, and wherein based on reflective liquid-crystal display.See also Fig. 1 (a), it is the profile construction synoptic diagram of a reflective liquid-crystal display, wherein pixel electrode 10 normally by aluminium (Al), aluminium neodymium alloy (Al-Nd) even be that the conductor of silver (Ag) high reflectance of etc.ing is finished, in order to the usefulness of while as the reflection horizon.And be can increase the reflectivity of above-mentioned reflecting electrode to reach the purpose of improving the display image quality, United States Patent (USP) proposes means for No. 5926240 and improves.Its main way is shown in Fig. 1 (b), and it is to form a dielectric layer 11 (embodiment is the silicon nitride layer of about 80 to 170 nanometers of thickness) again on the surface of above-mentioned reflecting electrode, can reach two kinds of effects thus.The first, as protective seam, may cause rough surface because of corrosion in order to avoid reflecting electrode, and then cause the decline of reflectivity.The second, utilize the refractive index (Refractive Index) of upper silicon nitride layer 1.6 to 1.9, and with between its THICKNESS CONTROL in 80 to 170 nanometers, and then reach the effect that increases lower floor's reflective electrodes reflects rate.

But above-mentioned means have a great disappearance, because this dielectric layer 11 can reduce by 12 obtainable driving voltages of top liquid crystal molecule relatively, therefore the driving circuit (not shown) of display must improve the driving voltage of being exported relatively, and then cause the excessive disappearance of power consumption of displays, and how to improve the problem of above-mentioned any means known, be development fundamental purpose of the present invention.

Summary of the invention

The present invention is a kind of LCD, and it comprises: a liquid crystal layer wherein includes a plurality of liquid crystal molecules; One reflective pixel electrode; One euphotic electrode is separately positioned on the both sides of this liquid crystal layer with this reflective pixel electrode, utilizes to add the just orientation of these liquid crystal molecules in this liquid crystal layer of may command of all voltage differences between this reflective pixel electrode and this euphotic electrode; And a printing opacity protective cover of conductor, being arranged between this liquid crystal layer and this reflective pixel electrode, it is covered in the surface of this reflective pixel electrode, descends in order to the reflectivity that prevents this reflective pixel electrode.

According to above-mentioned conception, the material of this reflective pixel electrode is one of to be selected from aluminium (Al), aluminium neodymium alloy (Al-Nd) and the silver high reflectance conductors such as (Ag) in the LCD of the present invention.

According to above-mentioned conception, the refractive index of this printing opacity protective cover of conductor in the LCD of the present invention (Refractive Index) is more than or equal to 1.95.

According to above-mentioned conception, the material of this printing opacity protective cover of conductor is one of to be selected from indium tin oxide (ITO), indium-zinc oxide (IZO) and the conducting polymer printing opacity conductors such as (ConductivePolymer) in the LCD of the present invention.

Description of drawings

The present invention can be able to more deep understanding by following graphic and detailed description.

Fig. 1 (a) is the profile construction synoptic diagram of two kinds of known reflective liquid-crystal displays (b).

Fig. 2 is that the present invention develops out the preferred embodiment synoptic diagram about reflection layer structure in the LCD.

Embodiment

See also Fig. 2, it is that the present invention develops out the preferred embodiment synoptic diagram about reflection layer structure in the LCD, the wherein setting of liquid crystal layer 20, reflective pixel electrode 21 and euphotic electrode 22, there is no too different with any means known, mainly be to utilize to add all voltage differences and control the orientation of liquid crystal molecule in this liquid crystal layer, and then reach the purpose of controlling light and shade in 22 of this reflective pixel electrode 21 and this euphotic electrodes.

And the present invention is characterized in to be arranged on a printing opacity protective cover of conductor 23 of 21 of this liquid crystal layer 20 and this reflective pixel electrodes; it is on as shown in the figure the surface that is covered in this reflective pixel electrode 21; in order to protect this reflective pixel electrode 21; avoiding may be because of the rough surface that is caused of corrosion, and then prevents that the reflectivity of this reflective pixel electrode 21 from descending.But because of this printing opacity protective cover of conductor 23 is finished with conductor; therefore can't produce that dielectric layer reduces the problem that liquid crystal layer can obtain driving voltage in any means known; so can improve the driving voltage of being exported relatively; and then the consumption of reduction display power, effectively reach development fundamental purpose of the present invention.

And above-mentioned reflective pixel electrode 21 is normally by aluminium (Al); aluminium neodymium alloy (Al-Nd) is even be that silver metallic conductors such as (Ag) is finished; this printing opacity protective cover of conductor 23 then can be selected indium tin oxide (ITO) for use; indium-zinc oxide (IZO) or conducting polymer printing opacity conductors such as (Conductive Polymer) is finished; and if select the printing opacity conductor of refractive index (Refractive Index) for use greater than known silicon nitride layer (refractive index 1.6 to 1.9); for example the refractive index of indium tin oxide (ITO) (Refractive Index) is about 1.95 to 2.2, and its effect that increases reflective pixel electrode 21 reflectivity will be better than any means known.

The present invention must be thought and the equivalence variation of work the neither protection domain that takes off claims by the personage Ren Shi craftsman who has the knack of this technology.

Claims

1, a kind of LCD is characterized in that comprising:

One liquid crystal layer wherein includes a plurality of liquid crystal molecules;

One reflective pixel electrode;

One euphotic electrode is separately positioned on the both sides of this liquid crystal layer with this reflective pixel electrode, utilizes to add the just orientation of these liquid crystal molecules in this liquid crystal layer of may command of all voltage differences between this reflective pixel electrode and this euphotic electrode; And

One printing opacity protective cover of conductor is arranged between this liquid crystal layer and this reflective pixel electrode, and it is the surface that is covered in this reflective pixel electrode, descends in order to the reflectivity that prevents this reflective pixel electrode.

2, LCD as claimed in claim 1, the material that it is characterized in that this reflective pixel electrode are one of to be selected from the high reflectance conductors such as aluminium, aluminium neodymium alloy and silver.

3, LCD as claimed in claim 1, the refractive index that it is characterized in that this printing opacity protective cover of conductor is more than or equal to 1.95.

4, LCD as claimed in claim 1, the material that it is characterized in that this printing opacity protective cover of conductor are one of to be selected from the printing opacity conductors such as indium tin oxide, indium-zinc oxide and conducting polymer.