Image on button

Hi!

I try to do button with image. But now have button with image size and picture as too small icon.

I used this script .What should I add? which strings?

var wDlg = new DzDialog;

var wBtn = new DzPushButton(wDlg );

var pixImage = new Pixmap("c:/2016-07-06_180440.png");

wBtn.pixmap = new Pixmap(pixImage );

wDlg.exec()