Catch the IE pop-up windows

Here is the script

;=============open IE with URL=========================
#include <IE.au3>
$sURL = "http://english.gmarket.co.kr/challenge/neo_goods/goods.asp?goodscode=207501754&pos_shop_cd=EN&pos_class_cd=90000024&pos_class_kind=T"
$oIE = _IECreate($sURL, 0, 0, 0)
$HWND = _IEPropertyGet($oIE, "hwnd")
WinSetState($HWND, "", @SW_MAXIMIZE)
;====Maxmize IE window=================================
WinActivate($HWND)
_IEAction($oIE, "visible")
_IELoadWait($oIE)
MouseMove(147,680)
sleep(1000)
MouseWheel("down",60)
Local $posArray = WinGetPos($HWND)
If @error Then
MsgBox(0,'you suck','')
Exit
EndIf
Local $xCenter =  ($posArray[2]/2)
Local $yCenter =  ($posArray[3]/2)
;MouseMove($xCenter,$yCenter)
MouseClick('left',$xCenter,$yCenter)
sleep(1000)
WinActive("http://gi.esm")

And when mouse clicks the image,it will pop up a new IE window
Then i need to save all images of the pop-up web.
Cause the title of the popping window is random,so how could i catch the pop-up IE window.
Thank your help......