Mr. Jun Hirakawa (平川純) is a Japanese lens designer best known for creating the Pentax FA 43mm Limited and FA 77mm Limited lenses during his time at Pentax.[1]

Hirakawa said at the time that he regretted his "early retirement" from Pentax in 2010, around the time that Hoya acquired the company, and was subsequently hired by Tamron.[2]

List of credited lens designs

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Hirakawa is credited with designing:

References

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  1. ^ a b c d RiceHigh (6 October 2010). "The Very Different Fates of Two ex-AOC Top Optical Engineers". RiceHigh's Pentax Blog. Retrieved 8 November 2017.
  2. ^ RiceHigh (8 July 2013). "News: Mr. Jun Hirakawa Now Works for Tamron and Mr. Blurry Cameraphone has Left Pentax China". RiceHigh's Pentax Blog. Retrieved 8 November 2017.
  3. ^ US patent 7317581, Ito, Takayuki & Hirakawa, Jun, "Fisheye lens system and a fisheye zoom lens system", published 2008-01-08, issued 2008-01-08, assigned to Pentax Corp. 
  4. ^ US patent 7116499, Hirakawa, Jun, "Wide-angle lens system", issued 2006-10-03, assigned to Pentax Corp. 
  5. ^ "SMC Pentax-DA 40mm F2.8 Limited Reviews - DA Prime Lenses - Pentax Lens Reviews & Lens Database".
  6. ^ US patent 5724193, Hirakawa, Jun, "Super wide angle zoom lens", published 1998-03-03, issued 1998-03-03, assigned to Pentax Corp. 
  7. ^ US patent 5546232, Hirakawa, Jun, "Two-group zoom lens", issued 1996-08-13, assigned to Pentax Corp. 
  8. ^ a b c US patent 4904070, Hirakawa, Jun, "Telephoto lens system", issued 1990-02-27, assigned to Pentax Corp. 
  9. ^ US patent 5264965A, Hirakawa, Jun, "Zoom lens", issued 1993-11-23, assigned to Pentax Corp. 
  10. ^ US patent 5233474A, Hirakawa, Jun, "Wide-angle lens system", issued 1993-08-03, assigned to Pentax Corp. 
  11. ^ US patent 5822132A, Hirakawa, Jun, "Soft focus lens", issued 1998-10-13, assigned to Pentax Corp. 
  12. ^ a b http://gw.org.za/images/Lens%20Technical%20and%20Trial%20Use%20Reports.%20SMC%20Pentax%20FA77mm%20and%20FA43mm.%20Hirakawa%20Jun%20and%20Adachi%20Masamitsu,%202000.pdf [bare URL PDF]
  13. ^ US patent 5061053A, Hirakawa, Jun, "Telephoto zoom lens system", issued 1991-10-29, assigned to Pentax Corp. 
  14. ^ "Login • Instagram". Archived from the original on 26 December 2021. {{cite web}}: Cite uses generic title (help)
  15. ^ US patent 5546232A, Hirakawa, Jun, "Wide-angle lens system of a retrofocus type", issued 1990-06-19, assigned to Pentax Corp. 
  16. ^ US patent 4934797A, Hirakawa, Jun, "Inner focus type telephoto zoom lens", issued 1996-11-05, assigned to Pentax Corp. 
  17. ^ US patent 5172274A, Hirakawa, Jun, "Large aperture, medium telephoto lens system", issued 1992-12-15, assigned to Pentax Corp. 
  18. ^ JP patent 5722730B2, 純 平川, "The camera shake correction zoom lens", issued 2015-05-27, assigned to 株式会社タムロン 
  19. ^ RiceHigh (16 August 2011). "RiceHigh's Pentax Blog: Some "Lost Stories" About the Three FA Limited Lenses". Ricehigh.blogspot.com. Retrieved 30 March 2018.
  20. ^ US patent 4747676A, Hirakawa, Jun, "Wide-angle seven-element lens system", issued 1988-05-31, assigned to Pentax Corp 
  21. ^ US patent 4836663A, Hirakawa, Jun, "Telephoto zoom lens system", issued 1989-06-06, assigned to Pentax Corp 
  22. ^ US patent 5448412A, Maruyama, Koichi & Hirakawa, Jun, "Telephoto zoom lens system", issued 1995-09-05, assigned to Pentax Corp 
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