Thrubeam measuring instruments measure the outer diameter, height, width, or thickness of an object, etc. These instruments can also be used for run-out, positioning, and dimension measurement. The measurement method includes Laser beam scanner or a beam of light converges into a parallel beam that projected onto a target. The shadow produced due to light being interrupted by the target is detected using a CCD image sensor or photodiode. There are 1D optical micrometer (LS series) and 2D optical micrometer (TM series) available
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