| April 1977 |
Sigma Koki Co., Ltd. founded in Tabame, Hidaka-cho, Iruma-gun, Saitama Prefecture (now Hidaka-shi, Saitama Prefecture) for manufacture and sales of laser-related optical equipment. |
| May 1982 |
Head office relocated to new head office facilities and factory at Harajuku, Hidaka-cho, Iruma-gun, Saitama Prefecture (now Hidaka-shi, Saitama Prefecture). |
| January 1983 |
Exports to United States begin. |
| April 1983 |
Manufacture and sales begin for motorized positioners. |
| October 1984 |
First edition of general catalog of standardized products released. Non-store sales operations begin. |
| November 1986 |
Tokyo sales office opens in Narimasu, Itabashi-ku, Tokyo, strengthened sales for motorized positioners. |
| March 1989 |
Noto Plant established in Noto Industrial Park in Ishikawa Prefecture. This plant became eligible for a grant created by Ishikawa Prefecture's advanced industry promotion ordinance. |
| July 1990 |
Head office and main factory functions relocated to new head office building and factory in Shimotakahagi-shinden, Hidaka-cho, Iruma-gun, Saitama Prefecture (now Hidaka-shi, Saitama Prefecture). |
| June 1992 |
Osaka sales office opens in Nishi-nakanoshima, Yodogawa-ku, Osaka, strengthening sales for the Kansai area. |
| January 1993 |
Kanazawa Technology Center opens in Tomizu-cho, Kanazawa-shi, Ishikawa Prefecture. |
| June 1993 |
Shanghai Sigma Koki Co., Ltd. established for mass porduction of laser-related optical products. |
| August 1994 |
In a move seeking to expand sales, Tokyo sales office relocated to larger facilities at Higashi-nippori, Arakawa-ku, Tokyo. |
| July 1995 |
OptoSigma Corporation established, primarily for the manufacture and sales of optical equipment in the US. |
| October 1995 |
Sigma-Technos Corporation established, for the sales of various laser optical equipment and measuring equipment. |
| October 1995 |
New Technology Center opens in Yatsukaho, Matto-shi, Ishikawa Prefecture. The new facility integrates the Kanazawa Technology Center. |
| November 1996 |
Company stock registered with the Japan Securities Dealers Association for over-the-counter stock offering. Capital increased to 999,750,000 yen through sales of stocks to the general public. |
| August 1997 |
Head office building and factory expanded to boost production of optical polished products. |
| January 1998 |
New factory for Shanghai Sigma Koki Co., Ltd. (in Shanghai, China) constructed, and operations launched. |
| May 1998 |
Sigma Koki establishes Tac Coat Co., Ltd. in IIda-shi, Nagano Prefecture through a joint venture with Natsume Optical Corporation to expand production system for optical coatings. |
| July 2000 |
Technology Center obtains "ISO 14001: 1996" certification. |
| February 2001 |
Head office and factory obtains "ISO 9001:1994" certification. |
| March 2001 |
Technology Center obtains "ISO 9002:1994" certification. |
| March 2001 |
Noto Plant obtains "ISO 9001:1994" certification. |
| March 2001 |
Sigma Koki acquires Tokyo head office building (in Sumida-ku, Tokyo) to expand and strengthen the sales promotion and head office functions. |
| July 2001 |
Sigma Koki signs basic agreements with Hamamatsu Photonics K.K. concerning capital and business alliances. |
| June 2002 |
The Sales and Administration headquarters relocated to Tokyo head office building (in Sumida-ku, Tokyo). |
| September 2002 |
Tokyo head office obtains "ISO 9001:2000" certification. |
| October 2002 |
Technology Center obtains "ISO 9001:2000" certification. |
| January 2003 |
Tokyo head office, head office and factory, and Osaka sales office obtain "ISO 14001:1996" certification. |
| July 2003 |
Noto Plant obtains "ISO 14001:1996" certification. |
| September 2003 |
Osaka sales office obtains "ISO 9001:2000" certification. |
| December 2004
| In accordance with establishment of JASDAQ security market, delist the over-the-counter stock offering and reregister stocks to JASDAQ securities exchange Inc. |
| November 2005 |
Expand facility of Shanghai Sigma Koki Co., Ltd. (in Shanghai, China) and start manufacture of optical hardware product. |
| February 2006 |
Unifying the Quality Control and the Environmental Conservation management system together and obtained integrated certificate of "ISO9001 : 2000" and "ISO14001 : 2004" in all domestic facilities. |
| March 2007 |
Expand facility of head office and factory to strengthen the optics department. |
May 2007 |
Reorganize Osaka sales office into Osaka branch. |
| June 2007 |
Kyushu sales office opens in Hakata-ku, Fukuoka. |
