Light guide structure of side turn signal lamp

A light guide structure of a side turn signal lamp, the light guide structure comprising:

• a light guide portion incorporated in a side turn signal lamp, the light guide portion being configured to allow light from a light source of the side turn signal lamp to enter the light guide portion through a predetermined incident surface, guide the light, and radiate the light toward an external environment from a predetermined radiation surface;
• and
• a light leakage prevention structure, wherein
• the light leakage prevention structure includes a plate-shaped portion integrated with the light guide portion in such a manner that the plate-shaped portion is connected to one end side of the light guide portion where the incident surface is disposed and extends in a plane direction parallel or non-parallel to the incident surface, and
• the plate-shaped portion includes an inclined surface on a front face of the plate-shaped portion at a position adjacent to an outer peripheral face of the light guide portion, the inclined surface being concavely inclined toward the outer peripheral face of the light guide portion.