Abstract: The liquid chromatograph detector of the present invention includes a nozzle communicating with a liquid chromatograph column. A piezoelectric element is firmly affixed to the nozzle and is actuated by an alternating current of a frequency appropriate to cause the firing of charged droplets of a predetermined, uniform size from the nozzle. The emitted droplets pass between two planar deflector plates which are maintained at a DC voltage sufficient to produce a transverse electric field between the plates. The electric field causes droplets passing between the plates to be deflected towards one of the plates and away from the other in a manner and to a degree sensitively dependent upon the charge acquired by the droplet upon discharge from the nozzle. A moving recording medium, such as paper, is positioned to receive the droplets passing between the deflector plates. If necessary, the recording surface is then processed so as to make the impinging droplets visible.