Lighting apparatus with lens having safety light-dispersing structures

• US 10,151,431 B2
• Filed: 10/17/2016
• Issued: 12/11/2018
• Est. Priority Date: 10/20/2015
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Nakano, Yoshiyuki
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): Fallahkhair, Arman B
• Application Number:
  US15/294,938
• Publication Number:
  US 20170108182A1
• Time in Patent Office: 785 Days
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21S 8/04 intended only for mounting on a ceiling or the like overhead structures F21S8/02 takes precedence; details of ceiling bases F21V21/03
• CPC Class Codes: F21V 3/049 Patterns or structured surfaces for diffusing light, e.g. frosted surfaces
• CPC Class Codes: F21V 5/045 the lens having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: F21V 7/0091 using total internal reflection
• CPC Class Codes: F21W 2131/405 for shop-windows or displays
• CPC Class Codes: F21Y 2115/30 Semiconductor lasers
• CPC Class Codes: G02B 5/0221 the surface having an irregular structure G02B5/0226 takes precedence
• CPC Class Codes: G02B 5/0263 with positional variation of the diffusing properties, e.g. gradient or patterned diffuser
• CPC Class Codes: G02B 5/1866 Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials G02B5/1809, G02B5/1828, G02B5/1833, G02B5/1838 and G02B5/1847 take precedence
• CPC Class Codes: G02B 6/0006 Coupling light into the fibre in general G02B6/4298
• CPC Class Codes: G02B 6/0008 the light being emitted at the end of the fibre

Abstract

A lighting apparatus having laser light as a light source is provided. The lighting apparatus includes: a light-emitter which radiates light of a wavelength different from a wavelength of the laser light; and a lens including a light distribution controlling structure that controls distribution of the light radiated from the light-emitter. The lens is disposed opposite a laser light entry side of the lighting apparatus. The light-emitter is disposed between the lens and the laser light entry side. The lens integrally includes, along an optical axis of the laser light, a light-dispersing structure configured to disperse the laser light.

Claims

1. A lighting apparatus which radiates visible light, with laser light as a light source, the laser light having a wavelength shorter than a wavelength of the visible light, the lighting apparatus comprising:

a light-emitter which, when irradiated with the laser light, radiates the visible light having the wavelength different from the wavelength of the laser light; and

a lens integrally including a light distribution controlling structure, the light distribution controlling structure including first structures that control distribution of the visible light radiated from the light-emitter, the lens being disposed opposite a laser light entry side of the lighting apparatus, the light-emitter being disposed between the lens and the laser light entry side,

wherein the lens integrally includes, in a region through which an optical axis of the laser light passes, a light-dispersing structure including third structures having at least one of a convex shape and a concave shape, the third structures configured to disperse the laser light having the wavelength shorter than the wavelength of the visible light, and

a distance between adjacent third structures among the third structures of the light-dispersing structure is at most equal to 1/100th of a distance between adjacent first structures among the first structures of the light distribution controlling structure, and is at least 1 micron and at most 100 microns on average.

2. The lighting apparatus according to claim 1,

wherein the lens includes the light distribution controlling structure and the light-dispersing structure on a single face.

3. The lighting apparatus according to claim 2,

wherein the light distribution controlling structure and the light-dispersing structure partially overlap on the single face.

4. The lighting apparatus according to claim 3,

a plurality of the third structures of the light-dispersing structure is disposed on surfaces of the first structures of the light distribution controlling structure in a region in which the light distribution controlling structure and the light-dispersing structure partially overlap.

5. The lighting apparatus according to claim 1,

wherein the lens includes the light distribution controlling structure on a first face and includes the light-dispersing structure on a second face.

6. The lighting apparatus according to claim 1,

wherein the light-dispersing structure includes a diffraction grating corresponding to the laser light.

7. The lighting apparatus according to claim 1,

wherein the third structures are non-periodically arranged.

8. The lighting apparatus according to claim 1,

wherein the light-dispersing structure includes a structure configured to cause light to be emitted in a predetermined pattern when the laser light passes through the light-dispersing structure.

9. The lighting apparatus according to claim 1,

wherein the light-dispersing structure comprises a fine diffraction grating configured to emit a predetermined message, pattern, or figure on a surface when the laser light passes through the light-dispersing structure.

10. The lighting apparatus according to claim 1,

wherein the third structures of the light-dispersing structure become smaller in stages with proximity to the region through which the optical axis of the laser light passes.

11. The lighting apparatus according to claim 1,

wherein the third structures of the light-dispersing structure become smaller continuously with proximity to the region through which the optical axis of the laser light passes.

12. The lighting apparatus according to claim 1,

wherein a size of the light-dispersing structure satisfies:

a≥

X·

tan θ

,

where a is a diameter of the light-dispersing structure,

X is a distance from a light exit end of the light source, and

θ

is an angle of divergence of the laser light exiting from the light exit end of the light source.

13. The lighting apparatus according to claim 1, further comprising:

a case in which the light-emitter is disposed, the lens being rigidly fixed to the case,

wherein the light-dispersing structure is rigidly fixed to the case via the lens.

14. The lighting apparatus according to claim 1,

wherein the light-emitter includes particles of at least one type in a resin or base material, the particles generating fluorescence when excited by the laser light.

15. The lighting apparatus according to claim 1, further comprising:

a case in which the light-emitter is disposed, the lens being rigidly fixed to the case;

a laser element provided externally of the case, the laser element emitting the laser light; and

a fiber extending from the laser element to the laser light entry side of the lighting apparatus for providing the laser light from the laser element to the light-emitter.