Direct Vision Spectroscope

RDV-1    A complete and light weight direct vision spectroscope without wavelength scale, for observing visible radiations from 400 to 750 mm.
RDV-2    A compact visible spectroscope with wavelength scale which allows the direct reading of spectral length and employs a prism for dispersion. It is also useful for flame test of basic radicals (sodium, strontium, potassium, copper etc.) There is a single eyepiece and independent focussing tube for the graticule, which carries an index at 590mm. with "D", marked right below the scale, (corresponding to the wave length of sodium light) can be calibrated to a known light source by adjustment of knurled screw. The amount of light admitted to the spectroscope can be regulated by a variable slit, adjusted by a knurled ring round the rating tube.