Ohara Corporation is the U.S. subsidiary of the Ohara Group. The parent company is headquartered in Japan. There are subsidiaries in a number of countries, including Japan, the United States, Germany, Hong Kong, Maylasia, Taiwan, and China.

Their web site lists areas of specialization, including:

• Optical Glass
• Polished Substates
• Fused Silica and Quartz
• IR Materials and Optical Crystals
• Low Expansion Glass
• Glass Ceramics
• Measurement Services

Optical glass

Among other things, Ohara is a major supplier of optical glass. Lens design programs

Optical lens design

Optical lens design refers to the calculation of lens construction parameters that will meet a set of performance requirements and constraints, including cost and schedule limitations....

 will typically include glasses in the Ohara catalog among their stock material choices, along with, for example, glasses in the Schott catalog.

On their website, Ohara describes a line of more than 130 environmentally safe glasses, produced without lead and arsenic.

They produce more than 300 tons of optical glass a month. The glass is available in a variety of forms, including strip, slab, cut blanks, and pressings.

Telescope mirror glass

Ohara supplied over 51,000 pounds of their E6 borosilicate glass

Borosilicate glass

Borosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are known for having very low coefficients of thermal expansion , making them resistant to thermal shock, more so than any other common glass...

 to be cast into the blank of the primary and tertiary mirror of the LSST