Model MLS-01: This is used when the Optical Flat is less than 150 mm diameter. The Optical Flat is placed over the polished part under inspection. The light bands are viewed over the Optical Flat from above.

Model MLS-02: The part to be inspected is placed over the Optical Flat and the light bands are viewed from beneath after reflection from a mirror. This Type Monochromatic Light Source is used when the part under inspection is thin and of large diameter. If an Optical Flat of large diameter is to be placed on such thin parts there would be deformation of fringes due to the weight of large size Optical Flat. To avoid this the part to be inspected is placed over the Optical flat and the fringes are viewed after reflection from a mirror placed below.

The Master surface of the Optical Flat face upwards and the test surface face downwards and are in contact to view the light bands. MLS-02 is suitable for use with 200 mm diameter Optical Flat. On request MLS to suit Optical Flats larger than 200 mm diameter is manufactured against specific Order.