主题：请教如何后台打印

                Dim doc2 As New PrintDoc
                Dim rm2 As New prt.RenderImage
                rm2.image = getimage("D:\用户目录\Documents\Scanned Documents\"& Customer(1) &".JPG")
                rm2.y = 10
                rm2.x = 10
                rm2.Width = "130%Parent" '设置尺寸为容器(页面)尺寸
                rm2.Height = "Auto" '高度由图片大小自动决定
                rm2.Style.ImageAlign.KeepAspectRatio = True '保持比例
                doc2.Body.Children.Add(rm2) '将图片对象加入报表
                Doc2.Print()

打印速度很慢，如何实现后台打印，不影响其它操作？