The present invention provides a method of measuring the thickness of a thin film or thin layer by a spectroscopic measurement, which is applicable to the measurement of a multiple layered film whose layers have different refractive indices. Thus, the frequency of input of an image signal to each pixel of the liquid crystal display device can be increased. In addition, the common line pattern is disposed on the substrate and covered with an insulation layer. The drive element is coupled with the clipper element and drives the lifting mechanism. 2, preferably y greater than about 0. A method for reducing products of incomplete combustion in fireplace emissions is presented including receiving fireplace emissions into a shell, heating said fireplace emissions to at least 1501\xb0 F.