摘要 |
An optical non-contact measuring probe for measuring small changes in distance to a target comprises a laser diode (12) coupled to a projecting fiber (14), a receiving fiber (32) spaced a fixed distance from the projecting fiber, and a linear array (36) spaced a fixed distance from the emitting face (34) of the receiving fiber. Light is projected from the projecting fiber to a small area on the target. Light rays reflected from the target are collected by the receiving fiber at an angle and are carried by the receiving fiber by total internal reflection through the emitting face to the linear array where it is detected as a circle having a diameter phiD. The distance from the probe to the target can be measured as inversely function of the diameter phiD.
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