Fresnel zone plate
Article No: 08577-03
To investigate the generation of convergent and divergent light beams with the assistance of Fresnel's zone theory. The diaphragm has a system of 40 light and dark rings. Limit circles between the rings have a diameter dn = 1.2 (n)0.5 mm (n = 1, 2, 3...40). Focal distance for He-Ne light: 56.9 cm. Dimensions (mm): 50 × 50.