JPH02288004A - Lighting apparatus - Google Patents

Abstract

PURPOSE:To allow light from a light source to be refracted and reflected on inclined surfaces of prism portions before being sent out efficiently through a radiation opening, by forming on a reflecting body, made of a light-transmitting material, prisms whose vertical angle is about 90 degrees and whose base is formed by the inner peripheral surface of the reflecting body in such a manner that they are arranged in parallel to each other circumferentially. CONSTITUTION:A reflecting body 10, made of a light-transmitting material such as glass, is a solid of revolution providing a second-order curved surface of parabolic revolution. On its outer peripheral surface are formed prism portions 13 having vertical angles of about 90 degrees and extending almost vertically from its top 11 to its irradiation opening, in such a manner that they are arranged in parallel to each other circumferentially. Upon activation of a light source 15 such as a high-brightness radiation lamp, the light strikes the reflecting body 10 from direction (b) which is different from normal line, and is refracted on the inner vertical surface 14. It is then refracted twice at about right angles, first on one inclined surface 16 of the prism portion 13, then on the other inclined surface 17, to be reflected toward (c) before being sent out through the irradiation opening 12. Since the inner peripheral surface of the reflecting body 10 is not in an arc shape, transmission occurs in the direction of (d), thereby reduction in total reflection efficiency can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a lighting fixture, for example, one used in a lighting facility suitable for store lighting.

(Prior Art) Conventional lighting equipment of this type uses a reflector or shade called a Brismatec reflector in which a total reflection prism is formed on the entire circumferential surface.

(Problems to be Solved by the Invention) As shown in FIG. There is a problem in that there is a large amount of transmitted light that is refracted by the inclined surface 4 and transmitted outward and does not contribute as reflected light, and that there is little effective reflected light, resulting in poor efficiency.

The present invention was made in view of the above problems, and the light emitted from the light source toward the reflector is incident on the inner surface of the reflector from a direction different from the normal line, and is refracted on the vertical surface of the inner surface of the reflector. is refracted by the inclined surface of the prism portion, reflected inward and emitted from the irradiation aperture, and the transmitted light is reduced.
The present invention provides a lighting fixture with enhanced total internal reflection efficiency.

[Structure of the invention]

(Means for Solving the Problems) A lighting fixture of the present invention includes a light source and a rotating body reflector that includes the light source, and the reflector is formed of a translucent material and has at least an outer circumferential surface. Prism parts having an apex angle of approximately 9G' and running in a substantially vertical direction from the apex toward the irradiation aperture are formed in parallel in the circumferential direction, and the inner circumferential surface is a substantially perpendicular surface in the circumferential direction at the same interval as the prism parts. It is characterized by being formed into a polygonal shape.

(Function) In the lighting fixture of the present invention, the light that is incident on the reflector from the light source is refracted at the vertical surface of the inner surface, and is directed by one inclined surface of the prism portion toward the other opposing inclined surface at a substantially right angle. The light is refracted, refracted toward the inside at a substantially right angle on the other inclined surface, and reflected, and then emitted from the irradiation aperture, reducing transmitted light and increasing total internal reflection efficiency.

(Example) The configuration of an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, IO is a rotating body reflector with a parabolic rotation quadratic curved surface formed of a transparent material such as glass, and a top portion 11 of this reflector 10 is attached to at least the outer peripheral surface of this reflector 10.
Prism part 13 in a substantially vertical direction toward irradiation aperture 12 from
are formed in parallel in the circumferential direction. The prism portion 13 is formed into a substantially isosceles triangular shape with an apex angle of approximately 90°. The inner circumferential surface of the reflector 10 is formed into a polygonal shape with substantially perpendicular surfaces 14 in the circumferential direction at the same intervals as the prism parts 13, corresponding to the prism parts 13.

15 is a high intensity discharge lamp (metal halide lamp)
The reflector 10 is included in the light source.

Next, the operation of this embodiment will be explained.

When the light source 15 is turned on, as shown in FIG.
The light from the reflector 10 is incident on the inner surface of the reflector lO from a direction different from the normal a, and the light incident from the light source 15 on the reflector 10 is incident on the inner surface of the vertical surface 14, as shown in FIG. It is refracted by one inclined surface 16 of the prism portion 13 at a substantially right angle toward the other opposing inclined surface 17, and is refracted inward at a substantially right angle by this other inclined surface 17, as indicated by a chain line C. The light is reflected as such and is emitted from the irradiation aperture 12. As shown in FIG. 3, unlike the shape in which the inner surface of the reflector 1G is formed into an arcuate surface, no light is transmitted as shown by the solid line d, and the amount of transmitted light is small.

〔Effect of the invention〕

According to the present invention, the reflector is formed of a light-transmitting material, and has prism portions arranged in parallel in the circumferential direction and having an apex angle of approximately 90° on at least the outer circumferential surface and extending in an approximately vertical direction from the apex toward the irradiation aperture. Since the inner circumferential surface has a polygonal shape with the inner circumferential surface being substantially perpendicular to the circumferential direction at the same interval as the prism part, the light emitted from the light source toward the reflector is directed toward the reflector from a direction different from the normal line. is incident on the inner surface of the reflector, refracted by the vertical surface of the inner surface of the reflector, refracted by the inclined surface of the prism section, reflected inward, and emitted from the irradiation aperture, reducing transmitted light and increasing total internal reflection efficiency. It is something.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of a lighting fixture showing an embodiment of the present invention, Fig. 2 is an enlarged explanatory view of a part of the reflector as above, and Fig. 3 is an explanatory view of the action of the prism section as above. , FIG. 4 is an enlarged explanatory view of a part of a conventional reflector. 1G...Reflector, 11...Top, 12...Irradiation aperture, 1
3. Prism surface, 14. Vertical surface, 15. Light source. Invented on April 27, 1989 Invented by Tatsuo Maruyama

Claims (1)

[Claims] (1) A light source and a rotary reflector containing the light source, the reflector being made of a translucent material, having an apex angle of approximately 90° on at least its outer peripheral surface, and extending from the apex to the irradiation aperture. A lighting device characterized in that prism portions are formed in parallel in the circumferential direction, and the inner circumferential surface is formed into a polyhedral shape with substantially perpendicular surfaces in the circumferential direction at the same intervals as the prism portions.