- 1935 OHARA Optical Glass Mfg. Co. Ltd. was established in Kamata, Tokyo as Jinpachi OHARA's private Enterprise.
- 1936 Optical Glass Melting started
- 1944 Reorganized as a Joint-Stock Company. Sagamihara factory was built.
- 1954 Platinum Pot Melting started
- 1958 Production of Lanthanum Glass started
- 1959 Appointed Chicago Aerial Industries(CAI) as an export agency
- 1961 Production of Strip Glass by Continuous Melting Method started
- 1965 Continuous Melting and Direct Pressing Production Method started
- 1967 CAI was mergedinto bourns Inc. Bourns optical Glass was appointed as a distributor in U.S.A and Europe
- 1969 OHARA Glass reached the moon (Apollo 11)
- 1975 Production of Low Refractive Index - Low Dispersion Glass "FK01" Started
- 1976 Production of Glass Beads started
- 1979 Production of Penta Prism by Direct Pressing started
- 1981 Ohara Corporation (USA) was established
- 1982 OHARA Glass flew into the universe with Space-Shuttle "Columbia"
- 1983 Volume Production of High Homogeneity Glasses started (±0.5∼±1.0X10-6)
- 1985 New Company Name "OHARA INC." introduced
- 1986 TAIWAN-OHARA OPTICAL CO., LTD. (Taiwan) was established
- 1987 OHARA Precision Corporation (Japan) was established
- 1988 Production of "Glass -Ceramics" started
- 1989 Introduction of 18" Interferometer (Zygo Mark IV)
- 1990 OHARA GmbH (Germany) was established
- 1991 OHARA OPTICAL(M)SDN.BHD. (Malaysia) was established
- 1992 T.Q.C.(Total Quality control) was introduced
- 1996 OHARA DISK(M)SDN.BHD. (Malaysia) was established
- 1998 All OHARA Products got ISO9001 Qualified
- 2000 Measurement service for refractive indices at Vacuum UV region started
- 2001 UNIQUE OHARA OPTICAL CO., LTD. (China) was established
- 2002 OHARA OPTICAL (HONG KONG) LTD.(China) was established
- 2005 Listing on First Section of Tokyo Stock Exchange
- 2006 Became a member of "Nippon Keidanren (Japan Business Federation)"
- 2007 OHARA Glass mounted the Lunar Orbit Explorer "KAGUYA (SELENE)"
- 2008 Ohara Quartz Co.,Ltd. was established
- 2011 NHG-OHARA OPTICS(XIANGYANG)CO.,LTD.(China) was established
- 2012 Taiwan Ohara Optical Material Co., Ltd.(Taiwan) was established
- 2015 NANOCERAM and Non-Browning Optical Glass has released.