HiTechnic NXT EOPD

“Accurately detect objects and small changes in distance to a target with the HiTechnic EOPD. The EOPD or Electro-Optical Proximity Detector uses an internal light source to detect the presence of a target or determine changes in distance to a target. By generating its own light source, the EOPD is able to filter out all external light signals so as a robot moves from bright areas to dimly lit areas or through shadows, the EOPD automatically compensates and only returns a signal based on its own light source. Targets can be accurately detected over distances up to about 8 inches (20 cm), depending on the target size, shape and reflective qualities.
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