Incandescent lamp life extension circuit 3a

(3) Incandescent lamp life extension circuit three.
    For the above two control circuits , the effective power of the bulb is almost reduced by half the moment it is turned on. If you want to reduce it even
more , you can use Figure 2-31 (a) and Figure 2- respectively. 31(b) circuit . The delay time is determined by Ri and C.