DROPLET INJECTION APPARATUS

PROBLEM TO BE SOLVED: To provide a droplet injection apparatus capable of precisely computing the interval between a head for injecting droplets and a platen or a medium to be applied without providing many light receiving parts or light emitting parts. SOLUTION: In a light emitting device 51, an emitting light L is emitted obliquely toward the platen 26 in a plane including a straight line along the moving direction of a recording head 4 and a normal line erected on the platen 26. As shown in the Fig.8 (A), the position of the recording head 4 when the emitting light L emitted from the light emitting device 51 and regularly reflected by the platen reaches a light receiving device 53 in the movement of the recording head 4 changes corresponding to the interval between the recording head 4 and the platen 26. The interval is computed based on the position of the recording head 4 when the emitting light L is received by the light receiving device 53. COPYRIGHT: (C)2007,JPO&INPIT