SENSOR DEVICE, HOUSING, AND COVER PORTION

A cover portion () includes a transmission portion () and a heater portion (). At least a portion of the heater portion () is disposed on a lower side (negative side of a sixth direction (V)) of the transmission portion () and on one of opposite lateral sides (positive side of a fifth direction (L)) of the transmission portion (). An amount of heat generated per unit length of the heater portion () in a direction along an outer periphery of the transmission portion () on the lower side (negative side of the sixth direction (V)) of the transmission portion () is higher than an amount of heat generated per unit length of the heater portion () in a direction along the outer periphery of the transmission portion () on the one of the opposite lateral sides (positive side of the fifth direction (L)) of the transmission portion ().