With 20-micron graduation and interpolation available up to 100 times from scanning unit, redesigned LIDA 400 Series offers 50 nm resolution and accuracies to ±1 micron. Multi-colored status LED on side of scanning unit indicates signal levels during installation and can be used as quick status check to determine functionality. For digital TTL versions with interpolation, interpolation circuits have been miniaturized to fit inside scanning unit housing.