DIFFUSION LENS STRUCTURE AND LIGHT EMITTING DEVICE INCLUDING SAME

摘要

Disclosed is a diffusion lens structure. The diffusion lens structure for diffusing light emitted from a light emitting element, according to an embodiment of the present invention, which has a cross-section bilaterally symmetric with respect to the reference optical axis thereof, comprises: a first lens surface that faces the light emitting element and through which light emitted from the light emitting element is input; and a second lens surface through which the light input through the first lens surface is output, wherein when the angle that the input light, emitted from the light emitting element and input to the first lens surface, forms with the reference optical axis is defined as θ1, and the angle that the output light, output from the second lens surface after the entrance of the input light to the first lens surface, forms with the reference optical axis is defined as θ4, the first and second lens surfaces are formed to satisfy θ4 < θ1 for at least a part of the light that is emitted from the light emitting element and input to the first lens surface.