asp.net imagebutton new window

I have a Telerik Grid. In that I have the following code in an .aspx page. What I want to happen is that when the user click on the imagebutton control it launches a new window to show that image. Note, I have seen some code which use Postback but they are blocked by popup blockers. The control's image is set via codebehind but that should not matter for this question. Here is my code. Thanks!

<asp:ImageButton ID="prod_image_main" runat="server" AlternateText="Product Main Image"
                 Height="500PX" Width="540PX"  />
 

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