Patent ID: 6215936
Filing Date: 2001-04-10
Classification: G02B,Y10S

Abstract:
A lightguide for guiding light from at least one side end plane, said lightguide comprising:a main body made of a transparent material, wherein said main body is approximately trapezoidal in cross-section so that said main body has a level surface and a rear surface, said rear surface being at an angle with respect to said level surface; anda multiplicity of any one of a speckled protruding pattern, a solid-line shaped protruding pattern, and a broken-line shaped protruding pattern located so as to protrude outwardly from said level surface of said main body, wherein any one of said speckled protruding pattern, said solid-line shaped protruding pattern, and said broken-line shaped protruding pattern has a cross-sectional width W located at a cross-section thereof so as to be perpendicular to an axis of a linear light source and said cross-sectional width W is approximately within a range defined by 10 .mu.m.ltoreq.W.ltoreq.200 .mu.m, said level surface constituting a light emitting surface, at a low density, in a region close to the linear light source, and at a high density, in a region far from the linear light source, so as to make a luminance distribution of light emitted from said light emitting surface approximately uniform.