| 摘要 |
<p>Associated with an envelope (3) housing a microlamp (4) and fastened to the inside of a tank (2) is a tailpiece (11) of transparent plastic material facing the lamp (4) through a connecting surface (19) and exhibiting at least an optical deviation surface aligned according to a given geometry with an end surface (14) exposed to the outside of the tank (2). Upon the action of the optical deviation surface (12), the light emitted from the microlamp (4) is reflected towards the end surface (14) or, vice-versa, refracted to the outside of the tailpiece (11), depending upon the fact that the tailpiece is above or below the level of the liquid (2a) contained in the tank (2), respectively. <IMAGE></p> |
