October 1935 Ohara Optical Glass Manufacturing Company was established in Kamata, Tokyo, Japan as Mr. Jinpachi Ohara's private enterprise.
November 1936 optical glass melting started.
February 1944 a new factory was completed in Sagamihara, Kanagawa-Ken, Japan.

February 1945 glass melting at Sagamihara factory started.
April 1946 first melting after World War II commenced at Sagamihara factory.

April 1958 LaSF glass production started.
February 1959 150 liter platinum pot melting and casting started.
November 1959 appointed Chicago Aerial Industries (CAI) as agent for North American, South American and European territories.

January 1961 production of strip glass by continuous melting method started.

October 1965 continuous melting and direct pressing production started.
January 1967 CAI was merged into Bourns Incorporated. Bourns Optical Glass was appointed as distributor in North America, South America, and Europe.
February 1967 production of large lens blanks for Schmidt camera started.

August 1975 production of low refractive index, low dispersion glass type FK01 started.
February 1979 production of lanthanum glass with direct pressing started. Bourns Optical Glass changed name to Recon Optical Glass.
May 1979 production of penta prism with direct pressing started.

August 1981 Cancelled distributorship contract with Recon Optical Glass and established Ohara Optical Glass Incorporated in the United States.
March 1982 Ohara glass traveled in space aboard the Space Shuttle "Columbia".
October 1982 started to deliver large size high homogeneity optical glass to Osaka University for laser fusion "GEKKO".
March 1983 mass production of high homogeneity optical glass for use in stepper cameras started.

May 1985 changed name to Ohara Incorporated.
October 1985 production of high index spectacle lens blanks started.
December 1985 Ohara Optical Glass Incorporated changed name to Ohara Corporation.
May 1987 founding of Taiwan Ohara Optical Company Limited.
February 1988 production of large diameter high homogeneity lanthanum glass blanks started.
August 1988 production of crystallized glass started.
September 1989 installation of 18" aperture interferometer (ZYGO Mark IV).

January 1990 founding of Ohara GmbH in Germany.
October 1990 changed glass type designations.
October 1990 founding of Ohara Optical (M) SDN. BHD. in Malaysia.
September 1991 production of "eco optical glass" started.
March 1992 "Ohara measurement service" started.

October 1996 Ohara receives ISO 9002 certification (Certification Number 955807).
October 1999 Ohara receives ISO 9001 certification (Certification Number 955807).

January 2000 Ohara GmbH celebrates 10 year anniversary.
February 2000 Mr. Sumimasa Yutani is appointed President of Ohara Incorporated, Japan. Mr. Yutani is also a Managing Director of Ohara GmbH.
April 2000 Ohara receives ISO 14001 certification (Environmental Management Systems). Registration No. E 133.