| 摘要 |
PURPOSE:To surely and directly detect the level of a liquid by preventing the adhesion of liquid drops to the part of the internal wall surface of a liquid storing chamber where the optical axis of transmitted light crosses and eliminating erroneous detection caused by light diffusion due to the lens effect of an adhering liquid drop. CONSTITUTION:A light emitting diode 34 and phototransistor 35 are arranged on both sides of part of a container 21 for storing a liquid 25, such as ink, etc., used for ink jet recorder or a liquid chamber 22 communicating with the container 21. Then the part of the internal wall surface of the container 21 or chamber 22 where the optical axis of transmitted light crosses is constituted of a member having high wettability against the liquid, such as a member formed of a fibrous material, such as high polymer unwoven fabric, etc., porous material or having narrow grooves on its surface. |
