This application claims priority of Taiwan Patent Application No. 098142842, filed on Dec. 15, 2009, the entirety of which is incorporated by reference herein.
1. Technical Field
The present disclosure relates to an illuminating device, and in particular relates to an illuminating device providing uniform illumination.
2. Related Art
Conventionally, the light beam 4 is reflected centrally by an area A of the ceiling 3. The brightness contrast between the area A and an area B of the ceiling 3 is thus strong. The high brightness contrast provides discomfort to users, wherein users may feel illumination is insufficient. The distribution of brightness on a ceiling may be used to define indoor illumination uniformity. Conventionally, a min/avg brightness uniformity ratio of a ceiling is about 0.34, and a min/max brightness uniformity ratio of a ceiling is about 0.06.
According to the disclosure, the illumination devices of the embodiments provide uniform illumination, decrease brightness contrast, and visual comfort.
An illuminating device is provided. The illuminating device includes a light source and a lampshade. The light source provides a first light beam and a second light beam. The lampshade includes a first curved surface and a second curved surface. The first light beam is refracted by the first curved surface. The second light beam is reflected by the second curved surface, and a curvature of the first curved surface differs from a curvature of the second curved surface.
An illuminating device is provided. The illuminating device includes a light source and a lampshade. The light source providing a first light beam, a second light beam, a third light beam and a fourth light beam. The lampshade includes a first curved surface, a second curved surface, a third curved surface and a fourth curved surface. The first light beam is substantially refracted by the first curved surface. The second light beam is substantially reflected by the second curved surface, and a curvature of the first curved surface differs from a curvature of the second curved surface. The third light beam is substantially reflected by the third curved surface. The fourth light beam is substantially refracted by the fourth curved surface, and a curvature of the third curved surface differs from that of the fourth curved surface.
An illuminating device is provided. The illuminating device provides illumination to a surface of a first body and a surface of a second body. The surface of the first body is substantially perpendicular to the surface of the second body. The illuminating device includes a light source and a lampshade. The light source provides a first light beam and a second light beam. The first light beam is substantially reflected by the first curved surface toward the surface of the first body. The second light beam is substantially reflected by the second curved surface toward the surface of the second body.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
The present disclosure can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
The following description is of the best-contemplated mode of carrying out the disclosure. This description is made for the purpose of illustrating the general principles of the disclosure and should not be taken in a limiting sense.
The illuminating device 100 is disposed in an inner space of a building. The space has a first body (ceiling, ground or wall) 10, and the first light beam 111 and the second light beam 112 are emitted to the first body (ceiling, ground or wall).
The illumination device of the first embodiment can uniformly distribute light over a first body. For example, in one embodiment, the first body (ceiling, ground or wall) 10 has a first light receiving area 11 and a second light receiving area 12. The first light receiving area 11 is adjacent to the second light receiving area 12. The second light receiving area 12 is relatively nearer the illuminating device 100 than the first light receiving area 11. The light beams with the light emitting angle between −60°˜+60° are guided by the first curved surface or the second curved surface and projected to the first light receiving area. The light beams with the light emitting angle between −60°˜+60° have high intensities, and is adapted for long distance projection to the first light receiving area 11. The first light beam with the light emitting angle between +60°˜+90° and the second light beam with the light emitting angle between −60°˜−90° are guided by the first curved surface or the second curved surface and projected to the second light receiving area 12. The first light beam with the light emitting angle between +60°˜+90° and the second light beam with the light emitting angle between −60°˜−90° have low intensities, and are adapted for short distance projection to the second light receiving area 12. The light is provided by the illumination device 100 can be uniformly projected to the first body (ceiling, ground or wall) 10, and reflected by the first body (ceiling, ground or wall) 10 to illuminate the space. Utilizing the illumination device 100 of the first embodiment of the invention, a min/avg brightness uniformity ratio of a ceiling is about 0.7, and a min/max brightness uniformity ratio of a ceiling is about 0.53. The illumination device 100 of the first embodiment decreases brightness contrast, provides uniform illumination, and provides visual comfort to users.
In one embodiment, a surface curvature of the first curved surface 121 is negative, and an absolute value of the surface curvature of the first curved surface is greater than a reciprocal of a distance between the light source 110 and the first curved surface 121. The first curved surface 121 substantially satisfies the following formula:
z=−0.11x2+(5×10−5)x4+(−0.1)y2+(−1.5×10−3)y4+(−1.5×10−5)y6
The x-y-z coordinates is defined as shown in
A surface curvature of the second curved surface 122 is negative, and an absolute value of the surface curvature of the second curved surface is greater than a reciprocal of the distance between the light source 110 and the second curved surface 122. The surface curvature of the second curved surface 122 differs from the surface curvature of the first curved surface 121. The second curved surface 122 substantially satisfies the following formula:
z=−0.17x2+(1.1×10−3)x4+(−6×10−5)x6+(−0.1)y2+(−1.5×10−3)y4+(−1.5×10−5)y6
In the second embodiment, light emitting angles of the first light beam 111′ and the second light beam 112′ are between 90° ˜0°. Light emitting angles of the third light beam 113′ and the fourth light beam 114′ are between 0°˜90°. The space is formed by first body (ceiling, ground or wall) 10 and second body (wall or ceiling, ground) 20. The first light beam 111′ and the second light beam 112′ are projected to the first body (ceiling, ground or wall) 10. The third light beam 113 and the fourth light beam 114′ are projected to the second body (wall or ceiling, ground) 20. The second body (wall or ceiling, ground) 20 is substantially perpendicular to the first body (ceiling, ground or wall) 10.
In the second embodiment, a surface curvature of the first curved surface 121′ is negative, and an absolute value of the surface curvature of the first curved surface is greater than a reciprocal of the a distance between the light source 110′ and the first curved surface 121′. The first curved surface 121′ substantially satisfies the following formula:
z=−0.1x2+(−3.7×10−6)x6+(−0.0)y2+(1.1×10−3)y4+(−2.25×10−5)y6
A surface curvature of the second curved surface 122′ is negative, and an absolute value of the surface curvature of the second curved surface is greater than a reciprocal of the a distance between the light source 110′ and the second curved surface 122′. The surface curvature of the second curved surface 122′ differs from the surface curvature of the first curved surface 121′. The second curved surface 122′ substantially satisfies the following formula:
z=−3.5x2+(−0.1)y2+(1.1×10−3)y4+(−2.25×10−5)y6
A surface curvature of the third curved surface 123′ can be positive or negative, and if the value is negative, an absolute value of the surface curvature of the third curved surface 123′ shall be smaller than a reciprocal of the a distance between the light source 110′ and the third curved surface 123′. The surface curvature of the third curved surface 123′ differs from the surface curvatures of the first curved surface 121′ and the second curved surface 122′. The third curved surface 123′ substantially satisfies the following formula:
z=−0.06x2+(1.8×10−4)x4+(−5.5×10−7)x6+10−10x8+(−0.1)y2+(1.1×10−3)y4+(−2.25×10−5)y6
Utilizing the illumination device 100′ of the second embodiment, the light beams provided thereby are uniformly reflected by a ceiling and a wall, and brightness contrast is further decreased. The illumination device 100′ of the second embodiment provides uniform illumination, and provides visual comfort to users.
Utilizing the illumination device 100″ of the third embodiment, the light beams provided thereby are uniformly reflected by a ceiling and a wall, and brightness contrast is further decreased. The illumination device 100″ of the third embodiment provides uniform illumination, and provides visual comfort to users.
In the embodiments above, the illuminating devices of the embodiments are utilized for indoor illumination. However, the invention is not limited thereby. The illuminating devices of the disclosure can be utilized in any illumination condition.
While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Number | Date | Country | Kind |
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TW098142842 | Dec 2009 | TW | national |