US Patent 7267839 Method of and apparatus for applying liquid material

Disclosed is a method, in which when a liquid material is applied to the application surface of an object of application by using a liquid material supply device having a syringe containing the liquid material and equipped with a needle having at its distal end an ejection hole from which the liquid material is ejected, an image of the distal end of the needle is taken laterally by a horizontal camera together with a height reference mark when an ascent/descent drive system of the liquid material supply device is set to a reference height, and the height position of the distal end of the needle is obtained from the difference between the height of the distal end of the needle and the height of the height reference mark.