Illumination Structure
An illumination structure includes a substrate having a front surface on which a light source is attached, and a reflector arranged on the front surface of the substrate to surround the light source, wherein the reflector includes a reflection wall part having a regular pyramid-like shape, and four inside surfaces of the reflection wall part having the regular pyramid-like shape include steep slope parts, respectively, having an angle larger than 7.5 degrees and smaller than 15 degrees with respect to a direction of an optical axis of the light source as a standard.
1. An illumination structure comprising:
a substrate having a front surface on which a light source is attached; and
a reflector arranged on the front surface of the substrate to surround the light source, wherein
the reflector comprises a reflection wall part having, in an inside surface thereof, four reflection surfaces having a regular truncated pyramid shape,
the four reflection surfaces of the reflection wall part having the regular truncated pyramid shape comprise steep slope parts, respectively, expanding at an angle larger than 7.5 degrees and smaller than 15 degrees with respect to a direction of an optical axis of the light source, and
each of the steep slope parts extends from a side of an emission part of the reflector toward a position of a corner between an upper surface and a side surface of a light emitting part of the light source such that the steep slope and the position are substantially adjacent.
2. The illumination structure according to claim 1 , wherein
a plurality of the light sources are arranged side by side on the substrate,
a plurality of the reflection wall parts of the reflector are provided in each of the light sources, and the plurality of the reflection wall parts are integrally connected to be a connected reflection part,
the connected reflection part comprises a frame wall part that defines an external shape of the entire connected reflection part and a dividing wall that divides an inside of the frame wall part into separate square shapes, and
the frame wall part comprises an extended part extending along the direction of the optical axis of the light source to be longer than the dividing wall.
3. The illumination structure according to claim 1 , wherein
a diffuser plate that diffuses light from the light source is provided on a side of the front surface of the reflector.
4. The illumination structure according to claim 1 , wherein
a mirror reflection layer is provided at least in the inside surface of the reflection wall part of the reflector.
5. The illumination structure according to claim 1 , wherein
a head-up display device is provided, wherein the head-up display device projects an image displayed on a display device,
the display device comprises a backlight that illuminates the image, and
the backlight comprises the reflector.