LIGHT GUIDE AND LINE ILLUMINATOR

摘要

[PROBLEMS] A light guide and a line illuminator incorporating it in which the deterioration of a read out image can be suppressed even when the document surface is floating by spreading the intensity distribution of light in the longitudinal direction at a position (document position) of an article being illuminated. [MEANS FOR SOLVING PROBLEMS] In a light guide (10) arranged such that a light entering from the end face exits from an exit face provided along the longitudinal direction while reflecting off the inner surface, a side face shape orthogonal to the longitudinal direction has a curved surface (1) of first elliptic arc, a curved surface (2) of second elliptic arc, a first exit face (3), a second exit face (4), and a light scattering part (5) formed at an elliptic focal position (or in the vicinity thereof) on the major axis plane of each ellipse. Condensing position of a light reflected off the first curved surface is different from the condensing position of a light reflected off the second curved surface.