The boundary area 224 may be formed such that an angle formed between a surface of the outer peripheral area 223B and a surface of the central flat portion 223A is an obtuse angle. An inclined surface of each of the outer peripheral areas 223B1 to 223B4 may be formed into a planar ...
(low) levels is used as the control signal, for example. The NPN transistor28is turned on when the H control signal corresponds to the signal that commands the LED14to turn on in a full lighting mode, while the NPN transistor28is turned off when the L control signal corresponds to the ...