Color filter substrate having color filter portions of different thickness, and overcoating layer on common electrode, LCD having the same, and method of manufacturing
View Patent ↗A color filter substrate includes a substrate, a color filter and a common electrode. The substrate includes a transmissive region and a reflective region adjacent to the transmissive region. The color filter is formed on the substrate, and the color filter includes a first portion formed in the transmissive region, and a second portion formed in the reflective region. The first and second portions have different thickness each other. The common electrode is disposed on the color filter. The common electrode includes a third portion formed in the transmissive region, and a fourth portion formed in the reflective region. The third portion and the fourth portion have different height each other with respect to the substrate. Thus, a luminance becomes uniform, even though a light passes through the liquid crystal layer of the reflective region twice, and a light passes though the liquid crystal layer of the transmissive region once.
1. A color filter substrate comprising:
a substrate including a transmissive region and a reflective region that is adjacent to the transmissive region;
a color filter formed on the substrate, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other;
a common electrode disposed on the color filter, the common electrode including a third portion formed in the transmissive region and a fourth portion formed in the reflective region, the third portion having a first height and the fourth portion having a second height that is lower than the first height with respect to the substrate; and
an overcoating layer on the common electrode.
2. The color filter substrate of claim 1 , wherein the first portion is thicker than the second portion.
3. The color filter substrate of claim 2 , wherein the ratio of the first portion to the second portion is in a thickness range from about 1.8:1 to about 2.2:1.
4. The color filter substrate of claim 1 , wherein the color filter includes an embossing portion that enhances optical properties.
5. The color filler substrate of claim 1 , further comprising a spacer formed on the common electrode.
6. The color filter substrate of claim 1 , wherein the overcoating layer is formed on the fourth portion of the common electrode.
7. The color filter substrate of claim 6 , further comprising a spacer formed on the overcoating layer.
8. The color filter substrate of claim 7 , wherein the overcoating layer includes an embossing portion that enhances optical property.
9. The color filter substrate of claim 7 , wherein the overcoating layer and the spacer is integrally formed with each other.
10. The color filter substrate of claim 1 , wherein the color filter further comprises a slit portion, and the slit portion is disposed over the fourth portion of the common electrode.
11. A method of manufacturing color filter substrate, comprising:
forming a color filter on a substrate that includes a transmissive region and a reflective region adjacent to the transmissive region, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other;
forming a common electrode on the color filter, the common electrode including a third portion formed in the transmissive region, and a fourth portion formed in the reflective region, the third portion having a first height and the fourth portion having a second height that is lower than the first height with respect to the substrate; and
forming overcoating layer on the common electrode.
12. The method of claim 11 , wherein the second portion includes embossing portion that enhances optical properties.
13. The method of claim 11 , wherein the overcoating layer is formed by:
coating a material including a photoresist on the color filter;
exposing the material via mask;
developing the material to form the overcoating layer.
14. The method of claim 13 , wherein the overcoating layer includes an embossing portion that enhances optical properties.
15. The method of claim 14 , wherein the mask includes a slit.
16. The method of claim 11 , farther comprising:
forming the overcoating layer on the common electrode; and
forming a spacer on the overcoating layer.
17. The method of claim 16 , wherein the overcoating layer and the spacer are integrally formed with each other.
18. The method of claim 17 , wherein the overcoating layer and the spacer are formed by:
coating a material including a photoresist on the color filter;
exposing the material via a mask including a transparent region, a semitransparent region and an opaque region; and
developing the material to form the overcoating layer and the spacer simultaneously.
19. A liquid crystal display panel comprising:
a first substrate including:
a substrate including a transmissive region and a reflective region that is adjacent to the transmissive region;
a color filter formed on the substrate, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other;
a common electrode disposed on the color filter, the common electrode including a third portion formed in the transmissive region, and a fourth portion formed in the reflective region, the third portion having a first height and the fourth portion having a second height that is lower than the first height with respect to the substrate; and
an overcoating layer on the common electrode;
a second substrate facing the first substrate; and
a liquid crystal layer interposed between the first and second substrates.
20. The liquid crystal display panel of claim 19 , wherein the first portion is thicker than the second portion.
21. The liquid crystal display panel of claim 20 , wherein the ratio of the first portion to the second portion is in a thickness range from about 1.8:1 to about 2.2:1.
22. A method of forming a liquid crystal display panel, including:
forming a first substrate including i) a substrate including a transmissive region and a reflective region that is adjacent to the transmissive region, ii) a color filter formed on the substrate, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other, iii) a common electrode disposed on the color filter, the common electrode including a third portion formed in the transmissive region, and a fourth portion formed in the reflective region, the third portion having a first height and the fourth portion having a second height that is lower than the first height with respect to the substrate; and iv) an overcoating layer on the common electrode;
forming a second substrate;
assembling the first and second substrates; and
forming a liquid crystal layer between the first and second substrates.
23. The method of claim 22 , wherein the overcoating layer formed on the common electrode and a spacer formed on the common electrode are integrally formed with each other.
24. The method of claim 23 , wherein the overcoating layer and the spacer are formed by:
coating a material including a photoresist on the color filter;
exposing the material via a mask including a transparent region, a semitransparent region and an opaque region; and
developing the material to form the overcoating layer and the spacer simultaneously.
25. A liquid crystal display apparatus comprising:
a first substrate including:
a substrate including a transmissive region and a reflective region that is adjacent to the transmissive region;
a color filter formed on the substrate, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other;
a common electrode disposed on the color filter, the common electrode including a third portion fanned in the transmissive region, and a fourth portion formed in the reflective region, the third portion having a first height and the fourth portion having a second height that is lower than the first height with respect to the substrate;
an overcoating layer on the common electrode;
a second substrate facing the first substrate;
a liquid crystal layer interposed between thin first and second substrates;
an upper optical film assembly disposed on an upper surface of the first substrate, the upper optical film assembly including an upper quarter-wave plate and an upper polarizer that is disposed on the upper quarter-wave plate; and
a lower optical film assembly disposed on a lower surface of the second substrate, the lower optical film assembly including a lower quarter-wave plate and a lower polarizer that is disposed on the lower quarter-wave plate.
26. The liquid crystal display apparatus of claim 25 , wherein the ratio of the first portion to the second portion is in a thickness range from about 1.8:1 to about 2.2:1.
27. A color filter substrate comprising:
a substrate including a transmissive region and a reflective region that is adjacent to the transmissive region;
a color filter formed on the substrate, the color filter including a first portion formed in the transmissive region, and a second portion formed in the reflective region, the first and second portions having different thickness from each other;
a common electrode disposed on the color filter, the common electrode including a third portion formed in the transmissive region, and a fourth portion formed in the reflective region, the third portion and the fourth portion having different heights from each other with respect to the substrate;
an overcoating layer fanned on the fourth portion of the common electrode; and
a spacer formed on the overcoating layer.
28. The color filter substrate of claim 27 , wherein the third portion of the common electrode has a first height, and the fourth portion of the common electrode has a second height tat is lower than the first height with respect to the substrate.