The present invention comprises an improved reflecting mirror for spotlights. Conventional reflecting mirrors for spotlights are well known in the art. As shown in FIG. 1, these mirrors generally comprise a parabolic shaped dish with a reflective inner surface (1) and an aperture in the axial center through which a light source protrudes. The light source can be an incandescent lamp (3) which emits light when a filament (2) is energized with current. The reflective inner surface of the parabolic shaped dish reflects light from the light source forward, thereby efficiently illuminating the light source.
In this general configuration of a floodlight reflecting mirror, the reflected illuminated light can have uneven brightness. This results from an unevenness in the light emission from the filament source. In extreme cases, a magnified image of the filament may be projected.
To address this problem, reflective mirrors have been developed with a plurality of small, approximately round reflective spots on the inner periphery of the mirror, each individual spot with either a concave or convex surface. This configuration is designed to diffuse the reflected light so that more evenly diffused lighting is achieved. Although this configuration may improve the evenness of illuminated light, the process of creating and manufacturing such a reflective parabolic mirror is very difficult.
Another reflective mirror configuration designed to solve the problem of uneven reflected light is shown in FIG. 2. In this configuration, the reflective mirror inner periphery (4) is subdivided into a plurality of expanding annular rings (5) with their center at the reflective mirror axial center with a protruding incandescent lamp (6). Each of these annular rings has a convex surface, so that the reflected light will diffuse and be distributed more evenly. With this configuration uneven shading of the filament in the direction of the optic axis of the incandescent lamp (6) is diffused and brightness is made uniform by the reflection on the surface of the annular rings, the unevenness of the filament in the direction of the whole circumference that exists in the orthogonal plane to the optical axis cannot be diffused.
Therefore an unresolved need exists in industry for an effective and economically feasible floodlight reflective mirror.