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Item no. C269 (cancel)
Type: cancel
Country: Slovakia
Date of use: 17 October 2007
Special cancel on postcard (CTO) “The Petzval Days 15 – 21 October 2017” [“Petzvalove Dni”] in Spišská Belá to honor Jozef Maximilian PETZVAL (1807 – 1891), mathematician, physicist and inventor, best known for his work in optics, e.g. for design of the achromatic portrait lens for daguerreotype cameras, consisting of 4 elements in 3 groups. The lens allowed crucial shortening of exposure time.
- Créée le
- Mardi 2 Avril 2019
- Tags
- Inventor
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- 1928
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