PerkinElmer offers a versatile product line of liquid sampling cells which utilize a specially designed Universal mount suitable for both FT-IR and dispersive instruments, and a wide variety of high quality window materials to meet your analytical needs. These windows are polished to precise tolerances of flatness. The first criteria to consider when selecting a window material is the wavelength range over which the spectrum must be measured. Other important considerations include solubility, reactivity, and the refractive index of the window material with respect to the sample. Sometimes mechanical and thermal characteristics may also be important.