John Dollond

Dollond, John

Born June 10, 1706; died Nov. 30, 1761. English optician.

In 1758, Dollond received a patent to produce achromatic objectives for telescopes. The first achromatic objectives were made in England as early as 1733, but they were highly imperfect. Dollond, who at first shared Newton’s opinion that it was impossible to make achromatic objectives, began to study the question in the light of L. Euler’s theory. After lengthy experiments he found a successful combination of lenses with good achromatic properties (a converging [positive] lens of crownglass and a diverging [negative] lens of flintglass). Dollond’s telescopes rapidly became popular.

WORKS

“An Account of Some Experiments Concerning the Different Refrangibility of Light.” Philosophical Transactions of the Royal Society, 1758, vol. 50.

单词	john dollond
释义	John Dollond Dollond, John Born June 10, 1706; died Nov. 30, 1761. English optician. In 1758, Dollond received a patent to produce achromatic objectives for telescopes. The first achromatic objectives were made in England as early as 1733, but they were highly imperfect. Dollond, who at first shared Newton’s opinion that it was impossible to make achromatic objectives, began to study the question in the light of L. Euler’s theory. After lengthy experiments he found a successful combination of lenses with good achromatic properties (a converging [positive] lens of crownglass and a diverging [negative] lens of flintglass). Dollond’s telescopes rapidly became popular. WORKS “An Account of Some Experiments Concerning the Different Refrangibility of Light.” Philosophical Transactions of the Royal Society, 1758, vol. 50.
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