if(document.images){
	P_sml0_on= new Image();
	P_sml0_on.src ="images/imp_on.gif";
	P_sml0_off= new Image();
	P_sml0_off.src ="images/imp_off.gif";

	P_sml1_on= new Image();
	P_sml1_on.src ="images/sit_on.gif";
	P_sml1_off= new Image();
	P_sml1_off.src ="images/sit_off.gif";

	P_sml2_on= new Image();
	P_sml2_on.src ="images/mit_on.gif";
	P_sml2_off= new Image();
	P_sml2_off.src ="images/mit_off.gif";

 }