One of the mysteries of the English language finally explained.
A lens made of crown glass and usually forming one component of an achromatic lens.
- ‘He experimented with different types of glass until he found the correct combination of flint and crown lenses in 1730.’
- ‘When the light exits the original crown lens, it does the usual thing and the blue light bends inward more than the red light.’
- ‘They are free from chips, scratches, and harmful striae, and are of good polish, apart from some deterioration of the polish on the second surface (near surface of the crown lens) due to long exposure to damp.’
- ‘After polishing the crown lens, a new lap - convex - is made and the third surface polished.’
- ‘The crown lens concentrate on the optical effect (for example focusing) and introduces some dispersion, and the second lens aims at balancing this dispersion while having the least possible optical influence on the lens function.’
- ‘After crown lenses are chemtempered, suspend them over the chemical bath for at least 15 minutes.’
- ‘For example, a strong positive crown lens with its low dispersion may be used in a doublet with a weaker negative lens of flint glass (high dispersion) to correct for chromatic aberration.’
- ‘The crown lens performs the desired optical effect (for example magnifying an image) and introduces some dispersion, and the flint lens aims at balancing this dispersion while having the least possible optical influence itself.’
- ‘Most often, the crown lens is a biconvex positive lens.’
- ‘Now lower the mating surface of the crown lens onto this puddle without entrapping air and let the lens settle into the oil unaided.’
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