Disclosed are a light reflective material which shows the color and texture of a base material thereof in the daytime and acts as a light reflector at night, and a preparation method thereof. Evoked response electrograms recorded at different AVD and VVD intervals are used to determine the extent of paced and intrinsic activation. The counter is initialized again after the count operation during the predefined period of time is completed. An actuator is connected to the latch member by for returning the latch member to the non-latching position thereby freeing the frames and the retainer. Ink flowing and leakage through the air inlet is thereby prevented. However the signals are made to differ with time in their phase andor amplitude.