Light guide unit

• US 7,532,800 B2
• Filed: 02/05/2007
• Issued: 05/12/2009
• Est. Priority Date: 06/14/2004
• Status: Expired due to Fees

• Current Assignee: Keiji Iimura
• Original Assignee: Keiji Iimura
• Inventors: Iimura, Keiji
• Primary Examiner(s): CONNELLY, MICHELLE R
• Application Number:
  US11/701,636
• Publication Number:
  US 20070147760A1
• Time in Patent Office: 827 Days
• Field of Search: 385/129, 385/145, 385/146, 385/901, 632/610, 632/612
• US Class Current: 385/146
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0036 2-D arrangement of prisms, protrusions, indentations or roughened surfaces
• CPC Class Codes: G02B 6/0043 provided on the surface of the light guide
• CPC Class Codes: G02B 6/0048 with stepwise taper
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: Y10S 385/901 Illuminating or display apparatus

Abstract

The disclosed is a light guide unit and a surface illuminator illuminating a liquid crystal display (LCD). The light guide unit (100) is composed of a surface lighting light guide (30) having a light emitting major surface (30a) and a light receiving side surface (30c); a channel light guide (20) having optical cores (21) to form a fiber optic channel array having light entrance core surfaces (21a) and light exit core surfaces (21b); and a distribution light guide (10) having a light distribution guide surface (10d) and a light receiving portion (10b) receiving light from the LED (200). The light guides (10, 20 and 30) are positioned respectively in that order to form a light guide unit (100). Each width (w1) and/or a pitch (p) of the optical cores (21) may change in accordance with a distance from the light receiving portion (10b). The channel light guide (20)/the distribution light guide (10) may have a linear shape or a nonlinear shape with “L”, “U” or “O” shape. The distribution light guide (10) may have a “V” shaped or rectangular reflector (40) with opposed surfaces (40a, 40b) to reflect light (L) from the LED (200) to face the reflector (40).

Claims

1. A light guide unit comprising:

a) a surface lighting light guide, b) a channel light guide and c) a distribution light guide;

a) the surface lighting light guide having a light emitting major surface and at least one light receiving side surface;

b) the channel light guide having a plurality of optical cores separated one another to form a linear or nonlinear fiber optic channel array, the channel array having a plurality of light entrance core surfaces and a plurality of light exit core surfaces to face the at least one light receiving side surface;

c) the distribution light guide having a linear or nonlinear light guide having at least one light receiving portion and at least one distribution light guide surface disposed to face the light entrance core surfaces; and

wherein each width of the optical cores increases in accordance with a distance from the at least one light receiving portion and/or each pitch between the optical cores decreases in accordance with a distance from the at least one light receiving portion.

2. The light guide unit according to claim 1, the distribution light guide further comprising at least one substantially “

V”

shaped reflector or at least one substantially triangular reflector, having opposed inclined surfaces, and wherein the reflector is disposed to face the at least one light receiving portion.

3. The light guide unit according to claim 2, wherein the reflector is disposed on/in at least one intermediate portion of the linear light guide.

4. The light guide unit according to claim 2, wherein the reflector is disposed on/in at least one cross portion of the nonlinear light guide having at least two linear light guides.

5. The light guide unit according to claim 1, further comprising a plurality of reflecting films disposed on the at least one distribution light guide surface at portions where the optical cores are not present, and wherein the reflecting films comprise light reflecting metallic films and/or substantially transparent solid film having a refractive index higher than the refractive index of the distribution light guide.

6. The light guide unit according to claim 1, wherein the light receiving portion is disposed on at least one end surface of the distribution light guide.

7. The light guide unit according to claim 1, wherein two or three light guides of the surface lighting light guide, the channel light guide and the distribution light guide are connected together, by a process selected from the group consisting of a laser cutting, an injection molding, a cast molding and a compression molding.

8. A light guide unit comprising:

a) a surface lighting light guide, b) a channel light guide and c) a distribution light guide;

a) the surface lighting light guide having a light emitting first major surface and at least one light receiving side surface;

b) the channel light guide having a plurality of optical cores separated one another to form a linear or nonlinear fiber optic channel array, the channel array having a plurality of light entrance core surfaces and a plurality of light exit core surfaces disposed to face the light receiving side surface;

c) the distribution light guide having a linear or nonlinear light guide having at least one light receiving portion and at least one distribution light guide surface disposed to face the light entrance core surfaces; and

wherein each of the channel light guide and/or the distribution light guide has the shape selected from the group consisting of substantially “

L”

like shape, substantially “

U”

like shape and substantially “

O”

like shape.

9. The light guide unit according to claim 8, the distribution light guide further comprising at least one substantially “

V”

shaped reflector or at least one substantially triangular reflector, having opposed inclined surfaces, and wherein the reflector is disposed to face the at least one light receiving portion.

10. The light guide unit according to claim 9, wherein the reflector is disposed on/in at least one intermediate portion of the linear light guide.

11. The light guide unit according to claim 9, wherein the reflector is disposed on/in at least one cross portion of the nonlinear light guide having at least two linear light guides.

12. The light guide unit according to claim 8, further comprising a plurality of reflecting films disposed on the light guide surface of the distribution light guide at portions where the optical cores are not present, and wherein the reflecting films comprise light reflecting metallic films and/or substantially transparent solid film having a refractive index higher than the refractive index of the distribution light guide.

13. The light guide unit according to claim 8, wherein each of the nonlinear channel light guide and the nonlinear distribution light guide comprises the substantially “

L”

like shape as a whole, in such a manner that each of the nonlinear channel and distribution light guides comprises an upright first linear portion and a lateral second linear portion connected together at that ends.

14. The light guide unit according to claim 8, wherein each of the nonlinear channel light guide and the nonlinear distribution light guide comprises the substantially “

U”

like shape as a whole, in such a manner that each of the nonlinear channel and distribution light guides comprises a substantially linear first leg portion, a substantially linear second leg portion opposed to, parallel with the first leg portion and a substantially linear bottom portion connected with the first and second leg portions.

15. The light guide unit according to claim 8, wherein each of the nonlinear channel light guide and the nonlinear distribution light guide comprises the substantially “

O”

like shape as a whole, in such a manner that each of the nonlinear channel and distribution light guides comprises a rectangular flame-like configuration.

16. The light guide unit according to claim 8, wherein the at least one light receiving portion is disposed on at least one end surface of the distribution light guide.

17. The light guide unit according to claim 8, wherein two or three light guides of the surface lighting light guide, the channel light guide and the distribution light guide are connected together, by a process selected from the group consisting of a laser cutting, an injection molding, a cast molding and a compression molding.

18. A light guide unit comprising:

a) a surface lighting light guide, b) a channel light guide and c) a distribution light guide;

a) the surface lighting light guide having a light emitting major surface and at least one light receiving side surface;

b) the channel light guide having a plurality of optical cores separated one another to form a linear or nonlinear fiber optic channel array, the channel array having a plurality of light entrance core surfaces and a plurality of light exit core surfaces disposed to face the at least one light receiving side surface;

c) the distribution light guide having a linear or nonlinear light guide having at least one light receiving portion and at least one distribution light guide surface to face the light entrance core surfaces and at least one tapered light guide surface opposed to the at least one distribution light guide surface;

wherein a distance between the at least one distribution light guide surface and the at least one tapered light guide surface decreases in accordance with a distance from the at least one light receiving portion;

wherein each of the channel light guide and/or the distribution light guide has a rod-like or bar-like linear shape as a whole, or wherein each of the channel light guide and/or the distribution light guide has a nonlinear shape selected from the group consisting of substantially “

L”

like shape, substantially “

U”

like shape substantially “

O”

like shape; and

the distribution light guide further comprising at least one substantially “

V”

shaped reflector or at least one substantially triangular reflector, having opposed inclined surfaces, and wherein the reflector is disposed to face the at least one light receiving portion.

19. The light guide unit according to claim 18, wherein the reflector is disposed on/in at least one intermediate portion of the linear light guide.

20. The light guide unit according to claim 18, wherein the reflector is disposed on/in at least one cross portion of the nonlinear light guide having at least two linear light guides.

21. The light guide unit according to claim 18 further comprising a plurality of reflecting films disposed on the light guide surface of the distribution light guide at portions where the optical cores are not present, and wherein the reflecting films comprise light reflecting metallic films and/or substantially transparent solid film having a refractive index higher than the refractive index of the distribution light guide.

22. The light guide unit according to claim 18, wehrein the at least one light receiving portion is disposed on at least one end surface of the distribution light guide.

23. The light guide unit according to claim 18, wherein two or three light guides of the surface lighting light guide, the channel light guide and the distribution light guide are connected together, by a process selected from the group consisting of a laser cutting, an injection molding, a cast molding and a compression molding.