Lighting device including diffusion lenses associated with hollow cylindrical light guide portions, and display device including the lighting device

• US 10,451,922 B2
• Filed: 06/08/2017
• Issued: 10/22/2019
• Est. Priority Date: 12/11/2014
• Status: Active Grant

• Current Assignee: Sakai Display Products Corporation (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sakai Display Products Corporation (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Teragawa, Daisuke
• Primary Examiner(s): Cariaso, Alan B
• Application Number:
  US15/617,051
• Publication Number:
  US 20170269431A1
• Time in Patent Office: 866 Days
• CPC Class Codes: G02B 6/0096 the lights guides being of the hollow type
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133606 including a specially adapted diffusing, scattering or light controlling members
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133628 with cooling means

Abstract

A lighting device has a housing having a bottom part and an opening, the bottom part being formed with through holes, and a substrate having light sources mounted on one surface thereof, the substrate being placed outside of the bottom part of the housing such that light emitted from the light sources is passed through the respective through holes and radiated to the opening of the housing. The lighting device also has light guide parts, each of which has a cylindrical shape, inserted through the through holes of the bottom part of the housing for guiding the light emitted from the light sources, respectively, and diffusion lenses provided inside of the housing for diffusing the light guided by the light guide parts, respectively. Each of the light guide parts is hollow and configured to reflect the light by an inner surface thereof so as to guide reflected light to an associated diffusion lens.

Claims

1. A lighting device comprising:

a housing including a bottom portion and an opening, the bottom portion including through holes;

a substrate including light sources mounted on one surface thereof, the substrate being outside of the bottom portion of the housing such that light emitted from the light sources is passed through respective through holes and radiated to the opening of the housing;

light guide portions, each of which has a cylindrical shape, provided through the through holes of the bottom portion of the housing to guide the light emitted from the light sources, respectively; and

diffusion lenses inside of the housing that diffuse light guided by the light guide portions, respectively, wherein

each of the light guide portions is hollow and reflects light by an inner surface thereof to guide reflected light to an associated diffusion lens,

the diffusion lenses have a diameter that is larger than a diameter of the through holes, and

the diffusion lenses cover the bottom portion around the through holes.

2. The lighting device according to claim 1, wherein an outer peripheral portion of each of the diffusion lenses is in contact with the bottom portion of the housing.

3. The lighting device according to claim 1, wherein the light guide portions and the diffusion lenses are defined as separate members.

4. The lighting device according to claim 1, further comprising:

a heat insulating material provided between the housing and the substrate.

5. The lighting device according to claim 1, further comprising:

a radiator that is in contact with another surface of the substrate opposite to the one surface of the substrate.

6. The lighting device according to claim 5, wherein the radiator includes a base in contact with the substrate, and radiating fins defined on the base in an erected manner.

7. The lighting device according to claim 5, wherein the radiator includes a base in contact with the substrate, and radiating pins defined on the base in an erected manner.

8. The lighting device according to claim 1, wherein another surface of the substrate opposite to the one surface of the substrate includes a heat radiation enhancing treatment.

9. The lighting device according to claim 1, wherein the substrate is made of metal.

10. A display device comprising:

the lighting device according to claim 1; and

a display panel provided to close the opening of the housing of the lighting device and control transmittance of light emitted from the light sources to display an image.

11. The lighting device according to claim 1, further comprising an optical sheet that aligns the light emitted from the light sources and diffused by the diffusion lenses to a direction normal to the optical sheet.

12. The lighting device according to claim 1, wherein the diffusion lenses each include a central recess portion.