When an optical flat is placed on another surface and illuminated under monochromatic light source, the light waves reflect off both the bottom surface of the flat and the surface it is resting on. The reflected waves interfere, creating a pattern of interference fringes, visible as light and dark bands, The spacing between the fringes in smaller where the gap is changing more rapidly, indicating a departure from flatness is one of the two surfaces, in a similar way to the contour lines on a map. A flat surface is indicates by a pattern of straight, parallel fringes with equal spacing, while other patterns indicate uneven surfaces.SALIENT FEATURES:
- Optical flats are made from BK-7 Grade A fine annealed material
- They are offered in two types i.e. Single sided and Double sided.
- Standard sizes available are 30 Ø, 50 Ø, 75 Ø, 100 Ø, 125 Ø and 150 Ø
- Accuracy offered are λ/4, λ/6, λ/10.
- Optical flats are offered in wooden storing cases.
- Other sizes and special sizes on request.