Fluorite lenses have been a crucial factor in the high image quality of Canon lenses. While natural fluorite is only suitable for small optical equipment, Canon developed its own technology to form large, high-purity artificial fluorite crystals for use in photography lenses. Chromatic aberration, which causes color fringing and haziness in images, is corrected by using a combination of concave and convex lenses. Ordinary glass has limitations in correcting chromatic aberration on all wavelengths, which is where fluorite becomes useful. Fluorite lenses have low-refractive, low-dispersion properties and can effectively correct chromatic aberration on telephoto lenses. Canon has successfully produced and incorporated fluorite lens elements in many lenses for superior image quality. The production process of fluorite lenses involves meticulous attention to detail in grinding, polishing, and coating the lenses. Canon has released 39 lenses that employ fluorite lens elements, which are highly praised by photographers who seek high image quality in telephoto lenses.
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