Abstract: The present invention aims at attaining a liquid surface level detecting apparatus, which can be used in various detection targets and usage environments without selecting a detection target, can efficiently irradiate a light to a liquid surface level detecting unit and detect a variation in a light reception amount of a light receiving means at a high sensibility, and can be excellent in durability, easy to manufacture, and be actually used. By placing a light shielding means 14 so as not to directly irradiate the light from a light emitting means 12 to a light receiving means 13, the light from the light emitting means is scattered by an optically scattering means 16, and a part of that scattering light is radiated to an outside by the liquid surface level detecting unit on a light radiating means (an optically transmitting member) 11.

Abstract: The present invention aims at attaining a liquid surface level detecting apparatus, which can be used in various detection targets and usage environments without selecting a detection target, can efficiently irradiate a light to a liquid surface level detecting unit and detect a variation in a light reception amount of a light receiving means at a high sensibility, and can be excellent in durability, easy to manufacture, and be actually used. By placing a light shielding means 14 so as not to directly irradiate the light from a light emitting means 12 to a light receiving means 13, the light from the light emitting means is scattered by an optically scattering means 16, and a part of that scattering light is radiated to an outside by the liquid surface level detecting unit on a light radiating means (an optically transmitting member) 11.