var preLoadImagesURL = new Array(
"./common/inqbt_01.gif",
"./common/inqbt_02.gif",
"./common/inqbt_sw.gif",
"./common/membt_01.gif",
"./common/membt_02.gif",
"./common/membt_sw.gif",
"./common/ordbt_01.gif",
"./common/ordbt_02.gif",
"./common/ordbt_sw.gif");

var preLoadImages = new Array(preLoadImagesURL.length);
for(i = 0; i < preLoadImages; i++){
    preLoadImages[i] = new Image();
    preLoadImages[i].src = preLoadImagesURL[i];
}