| 摘要 |
PURPOSE:To make it possible to detect the surface position, by embedding a plurality of light transmitting bodies, whose main component comprises silicon dioxide in a material to be measured so that the distances between ends of the light transmitting bodies and the surface of the material to be measured are different, and receiving the light passing the light transmitting bodies by a light receiving device. CONSTITUTION:An outer surface 11a of an abrasion material is lighted in a red hot state and moved back. Until the surface reaches one end of a light transmitting rod 15a, the infrared rays from said red hot region are sent to a photodiode 18a through the rod 15a. A generated electromotive force is amplified sent to a photocoder, and recorded. As shown in the Figure, the amount of the received light increases with the approach of the red hot regions to the transmitting rod 15a. When one end surface of the transmitting rod 15a is exposed to the outside, the red hot region, from which the infrared rays are emitted, disappears, and the amount of the light received by the diode 18a is temporarily decreased. When the one end surface is heated to a high temperature fusing and evaporation occur, the infrared rays are again emitted, and the amount of light is increased. The time, when the outer surface reaches one end of the light emitting rod 15a, can be detected as a time D. |
