achromatic中文

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Apochromaticlens

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Aspheric lenses have much lower f-numbers, allowing them to perform better than spherical lenses in light collection, projection, illumination, detection and condensing applications. Since the focal lengths are often very short, compact designs are frequently possible. Precision polished aspheric lenses are computer-optimized to achieve diffraction limited performance over high NAs and are available uncoated or with broadband visible or broadband NIR antireflection coatings. For more economic or OEM applications, our aspheric condenser lenses are fabricated from Schott B 270® glass and are available uncoated or with a single-layer MgF2 antireflection coating. If small diameter lenses are required, our molded glass aspheric lenses with visible or NIR antireflection coatings are available mounted in a stainless steel threaded holder or unmounted. Aspheric objective lenses are also available that offer the same magnification and on-axis performance as microscope objectives in a more compact package.

Asphericallens

Aspheric lenses have much lower f-numbers, allowing them to perform better than spherical lenses in light collection, projection, illumination, detection and condensing applications. Since the focal lengths are often very short, compact designs are frequently possible. Precision polished aspheric lenses are computer-optimized to achieve diffraction limited performance over high NAs and are available uncoated or with broadband visible or broadband NIR antireflection coatings. For more economic or OEM applications, our aspheric condenser lenses are fabricated from Schott B 270® glass and are available uncoated or with a single-layer MgF2 antireflection coating. If small diameter lenses are required, our molded glass aspheric lenses with visible or NIR antireflection coatings are available mounted in a stainless steel threaded holder or unmounted. Aspheric objective lenses are also available that offer the same magnification and on-axis performance as microscope objectives in a more compact package.

Describing a lens consisting of two or more optical components (elements), intended to correct for chromatic aberration. Commonly used as the objective of small refractors, the achromatic lens (or achromat) was invented in 1729 by the English optician Chester Moor Hall (1703–71) and first manufactured commercially by J. Dollond in 1758. It has one element of crown glass and another of flint glass. The dispersion (1) of the crown glass compensates for the chromatic error of the flint glass, while still leaving some refractive power. The two-element design is termed an achromatic doublet. It is practically impossible to correct all wavelengths of light, however, and most lenses adopt a compromise, bringing two particular wavelengths to a common focus, thus reducing the false colour. A lens that corrects for more than two wavelengths is termed an apochromatic lens.

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