LIGHTING APPARATUS

• US 20120134161A1
• Filed: 09/13/2011
• Published: 05/31/2012
• Est. Priority Date: 11/30/2010
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yokota, Masahiro, Ono, Osamu, Takahashi, Ken, Nishimura, Takashi, Matsuda, Hidemi, Kawamura, Nobuo, Ookawa, Takeshi, Morita, Shusuke
• Application Number:
  US13/231,245
• Publication Number:
  US 20120134161A1
• Time in Patent Office: Days
• US Class Current: 362/363
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21K 9/60 Optical arrangements integrated in the light source, e.g. for improving the colour rendering index or the light extraction
• CPC Class Codes: F21V 3/02 characterised by the shape
• CPC Class Codes: F21V 3/0625 the material diffusing light, e.g. translucent plastics
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]

Abstract

According to one embodiment, an lighting apparatus includes a base member, a light source configured to emit visible light, and a translucent cover including a translucent region which covers at least a front surface of the light source and emits the light emitted from the light source to the outside. The light source is provided on a front surface flat section of the base member, a luminous intensity of the light emitted from the light source has a directionality which is strong in a normal direction of the front surface flat section and becomes zero on a rear surface side. The translucent cover includes a domed shape having a maximum diameter at a position higher than a height of the position where the light source is arranged, and a transmittance of a region opposing the light source is 60% or less.

Claims

1. An lighting apparatus comprising:

a base member;

a light source configured to emit visible light; and

a translucent cover comprising a translucent region which covers at least a front surface of the light source and emits the light emitted from the light source to the outside, wherein

the light source is provided on a front surface flat section of the base member, a luminous intensity of the light emitted from the light source has a directionality which is strong in a normal direction of the front surface flat section and becomes zero on a rear surface side, and

the translucent cover comprises a domed shape having a maximum diameter at a position higher than a height of the position where the light source is arranged, and a transmittance of a region opposing the light source is 60% or less.

2. The lighting apparatus according to claim 1, wherein an average transmittance of the translucent cover is 40% or more.

3. The lighting apparatus according to claim 2, wherein when an angle between the normal direction of the light source and a surface normal direction of the translucent cover with which the normal line of the light source intersects is shown by a, the light source is arranged offsetting from a center axis so that angle a becomes 16°

or more.

4. The lighting apparatus according to claim 1, wherein the area of the translucent region viewed from a rear surface side is 20% or more to the area of the lighting apparatus viewed from the rear surface side.

5. The lighting apparatus according to claim 1, wherein when an angle between a normal direction of the light source and a surface normal direction of the translucent cover with which the normal line of the light source intersects is shown by a, the light source is arranged offsetting from a center axis so that angle a becomes 16°

or more.

6. The lighting apparatus according to claim 1, wherein, in the translucent cover, the transmittance of a rear surface side end of the translucent region is higher than the transmittance of the section of the translucent region opposing the light source.

7. The lighting apparatus according to claim 6, wherein the translucent cover is formed of a material having approximately constant transmittance, and a thickness of the translucent cover in the rear surface side end of the translucent region is thinner than a thickness of the translucent cover in the section of the translucent region opposing the light source.

8. The lighting apparatus according to claim 6, wherein the translucent cover is formed of a plurality of materials having a different transmittance and the transmittance of the material of the rear surface side end of the translucent region is higher than the transmittance of the material of the section of the translucent region opposing the light source.

9. The lighting apparatus according to claim 1, wherein the translucent cover is of an electric bulb type which comprises a maximum diameter section and a rear surface side region extending from the maximum diameter section to a rear surface side and wherein an inside diameter of the rear surface side region is maximized at an opening end of the translucent cover.

10. The lighting apparatus according to claim 1, wherein the lighting apparatus is an electric-bulb-type lighting apparatus configured to imitate an incandescent lamp and comprising an LED light source.

11. The lighting apparatus according to claim 1, wherein the lighting apparatus is a fluorescent-lamp-type lighting apparatus configured to imitate a fluorescent lamp and comprising an LED light source.