Demonstration Diffraction 3 in One

For demonstrating the principle of diffraction grating and the way in which its properties are dependent upon the number of lines per unit length. Comprises a card mount 90 x 40 mm approximately with three 16 x 9 mm apertures, each containing a diffraction grating replica. The gratings are of 100 lines/mm. 300 lines/mm and 600 lines/mm, respectively and are protected by cover glasses.