摘要 |
An optical monitoring system includes a ring-shaped object suspended by and engaged with a plurality of vertical plunger shafts. Normally, the vertical plunger shafts move upward and downward reciprocally and coherently, but independently, such that the ring-shaped object ascends or descends horizontally. A light transceiver device is affixed to one vertical plunger shaft. A plurality optical reflector elements are affixed to respective other plunger shafts. A light beam emanated from said light transceiver is reflected by the optical reflector elements and is eventually re-directed back to the light transceiver device.
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