PROBLEM TO BE SOLVED: To provide a droplet detection device or the like which accurately counts the number of droplets without being affected by disturbance light, and wherein power consumption is suppressed.SOLUTION: This droplet detection device 1 detecting the droplets includes: a light emission part 10 irradiating light crossing a path through which the droplets pass a light reception part 20 making the light irradiated from the light emission part input light and a control part 50 intermittently operating the light emission part and the light reception part. The droplet detection device includes a signal conversion part 30 converting a detection signal corresponding to a change of the input light from the light reception part, and the signal conversion part includes a comparison circuit 72 including: a first input terminal applied with a first potential that is a fixed potential and a second input terminal receiving the detection signal. When the light emission part does not irradiate the light, the control part performs control such that the first potential is not applied to the second input terminal.COPYRIGHT: (C)2013,JPO&INPIT【課題】 外乱光に影響されずに正確な滴下数をカウントし、消費電力を抑える液滴検出装置等を提供する。【解決手段】 液滴を検出する液滴検出装置1であって、液滴が通過する経路に交叉する光を照射する発光部10と、前記発光部から照射された光を入力光とする受光部20と、前記発光部および前記受光部を間欠動作させる制御部50と、を含む。前記受光部からの入力光の変化に応じた検出信号を変換する信号変換部30を含み、前記信号変換部は、固定電位である第1の電位が印加される第1の入力端子と、前記検出信号を受け取る第2の入力端子とを備えた比較回路72を含み、前記制御部は、前記発光部が光を照射しないときに、前記第2の入力端子に前記第1の電位が印加されるように制御する。【選択図】 図1
