Speedfam, a world renowned manufacturer of flat surface lapping & polishing machines, free abrasive machines, flatness measuring instruments and lapping & polishing consumable.
The speedfam check-flat "sees" rather than "feels"flatness. It provides instant visual read-out as to flatness of virtually any metal, ceramic, plastic or glass surface.
Check-flat provides the first mean ever of optical measurement of flatness in the range of 0.000001" to 0.0001". The readings are fast, accurate and easy.
To measure a piece or part, it is placed with the surface to be measured facing down on the round glass anvil set into the top of the check-flat.
The viewing window in the front of the instrument shows a reflection of the surface being measured. Overlaid with a "zebra-stripe" pattern of dark and light lines with a reference number at the rear of this grid. If the "zebra-stripes" are parallel throughout the measured surface, the surface is flat ...Within the tolerance reference indicated. If the "zebra pattern" appears out-of-straight, on the other hand, the surface is out-of-flat. The check flat grid pattern shows where and how much the surface is out of flat. This is indicated by the number of strip widths by which any non-parallel strips is bowed.
Applications:
This is good to check the flatness of lapped components having matte surfaces in the range of 0.0000001" to 0.0001".