VEHICULAR LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a vehicular lighting device capable of achieving improvement of radiation performance and reduction in weight.SOLUTION: A vehicular lighting device of the embodiment includes: a socket having a base part, and a first protrusion part protruding from one surface of the base part; and a light emitting module provided in the first protrusion part and having a light emitting element. The socket includes heat conductive resin in which thermal conductivity is equal to or greater than 7 W/(m K) and equal to or less than 11 W/(m K). When a maximum dimension of the base part in a direction orthogonal to a central axis of the vehicular lighting device is defined as A1(mm), a maximum dimension of the first protrusion part in the direction orthogonal to the central axis is defined as A2(mm), and power applied to the light emitting module is defined as W(W), (A1-A2)/W is equal to or greater than 1.0 and equal to or less than 6.5.SELECTED DRAWING: Figure 5