التفاصيل البيبلوغرافية
| العنوان: |
Light guide plate, backlight unit, liquid crystal display and method of manufacturing the light guide plate |
| Document Number: |
20050175283 |
| تاريخ النشر: |
August 11, 2005 |
| Appl. No: |
10/934480 |
| Application Filed: |
September 07, 2004 |
| مستخلص: |
A light guide plate that eliminates haze while obtaining a desired uniformity of luminance to enhance light efficiency. The light guide plate can be used with a backlight unit using the light guide plate and an LCD using the backlight unit. The light guide plate includes an incidence face to allow light emitted from a light source to be incident to the light guide plate, an outgoing face to allow the incident light to exit the light guide plate, a backside face opposite to the outgoing face, and mirror patterns provided at the outgoing face or backside face, and adapted to increase an exiting rate of the light at a low luminance region defined in a vicinity of the light source. The light guide plate is manufactured by a method including a mold machining operation including a prism face milling operation to form, at a mold, a prism face corresponding to a prism face of the light guide plate, and a mirror pattern milling operation to mill the prism face formed at the prism face milling operation using a bit having a predetermined cross-sectional shape, thereby forming mirror patterns at the prism face, and a light guide plate injection-molding operation to mill a molten resin into the mold completely machined at the mold machining operation, thereby injection-molding the light guide plate. |
| Inventors: |
Park, Hye-eun (Suwon-si, KR); Suh, Je-wan (Suwon-si, KR) |
| Claim: |
1. A light guide plate comprising: an incidence face to allow light emitted from a light source to be incident to the light guide plate; an outgoing face to allow the incident light to exit the light guide plate; a backside face opposite to the outgoing face; and mirror patterns provided at the outgoing face or backside face and adapted to increase an exiting rate of the light at a low luminance region defined in a vicinity of the light source. |
| Claim: |
2. The light guide plate according to claim 1, further comprising: a prism face provided at the outgoing face or backside face, wherein the mirror patterns are formed at the prism face. |
| Claim: |
3. The light guide plate according to claim 2, wherein the mirror patterns have a mean inclination that is reduced gradually as they extend away from the incidence face. |
| Claim: |
4. The light guide plate according to claim 3, wherein the mirror patterns have a height that is reduced gradually as they extend away from the incidence face. |
| Claim: |
5. The light guide plate according to claim 3, wherein the mirror patterns have a pitch that increases gradually as they extend away from the incidence face. |
| Claim: |
6. The light guide plate according to claim 3, wherein: the light guide plate has a tapered structure having a thickness that is reduced gradually as it extends away from the incidence face; and the face opposite to the prism face is roughened to have a uniform mean inclination at the entire portion thereof. |
| Claim: |
7. The light guide plate according to claim 6, wherein each of the mirror patterns has a convex arc shape having a round surface or a polygonal surface and has a mean inclination of 25° or less. |
| Claim: |
8. A backlight unit comprising: a light source; and a light guide plate including an incidence face to allow light emitted from a light source to be incident to the light guide plate, an outgoing face to allow the incident light to exit the light guide plate, a backside face opposite to the outgoing face, and mirror patterns provided at the outgoing face or backside face and adapted to increase an exiting rate of the light at a low luminance region defined in a vicinity of the light source. |
| Claim: |
9. The backlight unit according to claim 8, wherein the light guide plate further includes a prism face provided at the outgoing face or backside face, and the mirror patterns are formed at the prism face. |
| Claim: |
10. The backlight unit according to claim 9, wherein the mirror patterns have a mean inclination that is reduced gradually as they extend away from the incidence face. |
| Claim: |
11. The backlight unit according to claim 10, wherein the mirror patterns have a height that is reduced gradually as they extend away from the incidence face. |
| Claim: |
12. The backlight unit according to claim 10, wherein the mirror patterns have a pitch that increases gradually as they extend away from the incidence face. |
| Claim: |
13. The backlight unit according to claim 10, wherein the light guide plate has a tapered structure having a thickness that is reduced gradually as it extends away from the incidence face, and the face opposite to the prism face is roughened to have a uniform mean inclination at the entire portion thereof. |
| Claim: |
14. The backlight unit according to claim 13, wherein each of the mirror patterns has a convex arc shape having a round surface or a polygonal surface and has a mean inclination of 25° or less. |
| Claim: |
15. A liquid crystal display comprising: a liquid crystal panel; and a backlight unit adapted to irradiate illumination light onto the liquid crystal panel, the backlight unit including: a light source; and a light guide plate including an incidence face to allow light emitted from a light source to be incident to the light guide plate, an outgoing face to allow the incident light to exit the light guide plate, a backside face opposite to the outgoing face, and mirror patterns provided at the outgoing face or backside face and adapted to increase an exiting rate of the light at a low luminance region defined in a vicinity of the light source. |
| Claim: |
16. The liquid crystal display according to claim 15, wherein the light guide plate further includes a prism face provided at the outgoing face or backside face, and the mirror patterns are formed at the prism face. |
| Claim: |
17. The liquid crystal display according to claim 16, wherein the mirror patterns have a mean inclination that is reduced gradually as they extend away from the incidence face. |
| Claim: |
18. The liquid crystal display according to claim 17, wherein the mirror patterns have a height that is reduced gradually as they extend away from the incidence face. |
| Claim: |
19. The liquid crystal display according to claim 17, wherein the mirror patterns have a pitch that increases gradually as they extend away from the incidence face. |
| Claim: |
20. The liquid crystal display according to claim 17, wherein the light guide plate has a tapered structure having a thickness that is reduced gradually as it extends away from the incidence face, and the face opposite to the prism face is roughened to have a uniform mean inclination at the entire portion thereof. |
| Claim: |
21. The liquid crystal display according to claim 20, wherein each of the mirror patterns has a convex arc shape having a round surface or a polygonal surface and has a mean inclination of 25° or less. |
| Claim: |
22. A method of manufacturing a light guide plate, comprising: a mold machining operation including a prism face milling operation to form, at a mold, a prism face corresponding to a prism face of the light guide plate, and a mirror pattern milling operation to mill the prism face formed at the prism face milling operation using a bit having a predetermined cross-sectional shape to form mirror patterns at the prism face; and a light guide plate injection-molding operation to inject a molten resin into the mold machined at the mold machining operation to injection-mold the light guide plate. |
| Claim: |
23. The method according to claim 22, wherein the mold machining operation further includes a roughening operation to roughen the mold to form, at the mold, a roughened face corresponding to a backside face of the light guide plate opposite to the prism face of the light guide plate. |
| Claim: |
24. A backlight unit to irradiate illumination light onto the backside of an LCD panel, the backlight unit comprising: a light source to emit light; and a light guide plate including: an incidence face to receive the emitted light, an outgoing face to allow the light to exit toward the LCD panel, and a backside face opposite to the outgoing face and having mirror patterns thereon to increase an exiting rate of the emitted light in a low luminance region of the outgoing face; a reflection sheet arranged at the backside face of the light guide plate; a prism sheet laminated on the outgoing face; and a diffusion sheet laminated on the prism sheet. |
| Claim: |
25. The backlight unit of claim 24, wherein the mirror patterns linearly protrude from the backside face, each mirror pattern forming an arc from a valley defined between adjacent ones of the linear protrusions. |
| Claim: |
26. The backlight unit of claim 25, wherein the mirror patterns extend in parallel with the incidence face of the light guide plate. |
| Claim: |
27. The backlight unit of claim 26, wherein the mirror patterns each have a mean length of about 50 μm. |
| Claim: |
28. A liquid crystal display (LCD) comprising: an LCD panel; and a backlight unit to irradiate illumination light onto the backside of the LCD panel, the backlight unit comprising; a light source to emit light, a light guide plate having an incidence face to receive the emitted light, an outgoing face to allow the light to exit toward the LCD panel, and a backside face opposite to the outgoing face and having mirror patterns to increase the light exiting the outgoing face in a predetermined region thereof, a reflection sheet arranged at the backside face of the light guide plate, a prism sheet laminated on the outgoing face of the light guide plate, and a diffusion sheet laminated on an side of the prism sheet opposite to the light guide plate. |
| Claim: |
29. A method of manufacturing a light guide plate, comprising: injection-molding body made of a transparent resin having two major faces and four minor faces forming a light guide plate with a tapered cross section; performing a first milling operation on one suface of the light guide plate to form a prism face thereon; and performing a second milling operation on the prism face using a bit having a predetermined cross-sectional shape to form mirror patterns on the prism face. |
| Claim: |
30. A light guide plate to receive light from a light source and to output the light, comprising: an incident face to receive the light; an outgoing face disposed in a direction substantially perpendicular to the incident face to output the light; a backside face disposed in a direction having an angle with respect to the outgoing face; and a mirror pattern formed on the outgoing face or the backside face and having a convex shape protruding from the outgoing face of the backside face. |
| Current U.S. Class: |
385036/000 |
| رقم الانضمام: |
edspap.20050175283 |
| قاعدة البيانات: |
USPTO Patent Applications |