Application of the Piezoelectric Capillary Injector in Analog Recording

A piezoelectric capillary injector is considered. It has been used instead of the pen in an analog recorder. The advantage with this method is that the amount of ink can be modulated and the line width becomes independent of pen and paper speeds. For this purpose the frequency of the electric pulses to the injector has been modulated by the pen and paper speeds and the results are compared with the results of constant frequency. It has also been shown how the injector can be used to print some digital values at the same time that the curve is drawn.