D. V. Spectroscope With Wavelength Scale Portable and precise, the instrument provides direct wavelength readings of visible spectrum from 400nm to 750nm with each scale division representing 5nm. The spectrum is viewed in the plane of scale and for error free readings, D-line on scale can be adjusted. Incorporates a 10x10mm Amici type 3-element prism train, telescopic focusing housed in brass body and variable optical slit adjustable by knurled head rotating ring. Wooden storage case included. Qty :