Patent ID: 8789992

Claim:
An illuminating device comprising: a light source for emitting light; a shield filter disposed at a front of the light source; a light pipe for distributing the light from the light source; and a reflecting cap, wherein the light source is disposed at a first end of the light pipe, and the reflecting cap is disposed at a second end of the light pipe opposite to the light source, wherein the light pipe includes: a base pipe having a hollow conduit, and an optical film including a plurality of prism patterns each extending along a longitudinal direction of the base pipe, the optical film provided in the hollow conduit of the base pipe, and at least one of a reflector and an extractor on the base pipe, wherein a glass transition temperature of the optical film ranges from approximately 110° C. to approximately 180° C., wherein a width of the extractor at an area near the light source is less than a width of the extractor at an area further away from the light source, wherein at least one of protrusions and indentations are provided on a surface of the base pipe, and the surface of the base pipe has a surface roughness ranging from approximately 3 μm to approximately 30 μm, wherein a density of at least one of the protrusions and the indentations increases according to distance from the light source at the first end of the light pipe to the reflecting cap at the second end of the light pipe, and wherein at least one of the protrusions and the indentations is formed more densely in areas near the reflecting cap than in areas near the light source.