Grinding is processing glass, which has been press molded and annealed, into a drawing shape.

During grinding, various abrasive grains or grindstones such as diamonds, alumina, and SiC (Silicon carbide) etc, are used with grinding fluid. When grinding with abrasive grains, there is a gradual change grain size from coarse to fine.

Grinding process can be roughly classified into machining process and hand lapping by master craftsmen. In the machining process, generators and surface grinding machines, equipped with diamond cutters, are used. Hand lapping and machine processing are selected according to the production volume, material and required performance of the finished product.

NITTO OPTICAL does not rely on the products which are grinded at subcontractors. NITTO OPTICAL has developed its original, highly accurate tooling, and grinds close to the final product regardless of the product size. That enables NITTO OPTICAL to proceed with the super high precision polishing in the next procedure. Furthermore, by pursuing the reduction in polishing time, mass production in short lead time has also become possible.