AERATION MEMBER AND AERATION DEVICE

The aeration member 20 is a porous body for discharging water vapor in the interior of a closed lamp housing. The aeration member 20 has small pore diameter structures 21 for preventing infiltration of liquid water and contaminants into the lamp housing while forming a flow path for discharging the water vapor from the interior of the lamp housing to the exterior, and large pore diameter structures 22 having larger diameters than that of the small pore diameter structures 21 and being provided in such a manner as to communicate with the small pore diameter structures 21. The above allow for the provision of an aeration member and an aeration device that can promote the transfer of water vapor between the interior and the exterior of the housing.