SOC Polishing Technologies

Polishing

MRF (Magnetorheological Finishing)

SOC owns several MRF polishing machines and makes profile irregularity finishing tailored to customers' specifications.
(It can support a plane precision of about up to λ/50 and an outer diameter of up to Φ200mm.)
MRF polishing is a revolutionary optical polishing technology in which a given amount of magnetic viscoelastic fluid is flown into a rotatory wheel to be able to obtain a constant amount of polishing and conduct high-precision polishing.
The NC program automatically developed can accomplish high-precision processing.

*Appearance of MRF system and processing by the system

Polished material example

• Various glass materials including synthetic quartz, calcium fluoride crystal, etc.
• Some materials cannot be processed because an electromagnet generates a magnetic field.

Measurement and Evaluation

SSI (Subaperture Stitching Interferometer)

It was difficult to measure a profile irregularity all over a large-diameter or high-NA lens measuring object by traditional technologies. However, a subaperture stitching interferometer (SSI) developed by QED Technologies has enabled us to measure the entire surface of the measuring object with a high precision of several tens of λ or more.
Focusing on this technology earlier, SOC adopted this measuring machine to ensure high accuracy of several tens of one or more for the profile irregularity on the entire surface of any optically finished product.

NewView

SOC owns a surface roughness measuring machine of non-contact microscope type (New View) that is Zygo's leading-edge white-light interferometry.
In particular, the surface roughness of the product in the domain of DUV heavily affects the performance of optical systems, and is greatly involved in the loss of laser damage threshold, a transmittance and optical contrast. This is one of product qualities that are strictly controlled by SOC.