| 摘要 |
<p>A level detector has a bubble-contained tube ( 2 ) interposed between a projector ( 5 ) and a light receptor ( 6 ) including photosensitive elements ( 23a - 23h ), in which an inclination of a detector body ( 1 ) is detected and indicated in an levelness indicator ( 8, 9 ) by a discriminating circuit ( 7 ) to discriminate reactional photosensitive elements irradiated with light beams coming straightforwardly across the bubble-contained tube ( 2 ) from the projector ( 5 ) without the travelling course of the light beams being prevented by the bubble. <IMAGE> <IMAGE></p> |
