def __init__(self, parent, *arg, **kw):
        Panel.__init__(self, parent, *arg, **kw)

        # designer ui
        self.ui = Ui_Panel()
        self.ui.setupUi(self)

        self.ui.scan_length.setValue(self._ins.get_scan_length())
        self.ui.pixel_time.setValue(self._ins.get_pixel_time())
        self.ui.nr_of_points.setValue(self._ins.get_nr_of_points())
        self.ui.gaussian_fit.setChecked(self._ins.get_gaussian_fit())
        self.ui.counter.setValue(self._ins.get_counter())

        self.ui.scan_length.valueChanged.connect(self._set_scan_length)
        self.ui.pixel_time.valueChanged.connect(self._set_pixel_time)
        self.ui.nr_of_points.valueChanged.connect(self._set_nr_of_points)
        self.ui.gaussian_fit.toggled.connect(self._set_gaussian_fit)
        self.ui.counter.valueChanged.connect(self._set_counter)

        self.ui.start.pressed.connect(self._start)

        # set up plot
        for p in self.ui.xplot, self.ui.yplot:
            p.bottom_axis.title = 'x [um]'
            p.left_axis.title = 'counts [Hz]'
            p.plot.padding = 5
            p.plot.padding_bottom = 30
            p.plot.padding_left = 70
        self.ui.yplot.bottom_axis.title = 'y [um]'