# SF11 optical glass

SF11 is a specialized type of optical glass with a high refractive index and a relatively low Abbe number, indicating higher dispersion properties. This glass type is particularly useful in optical systems where substantial light bending is required, such as in telephoto lenses, high-magnification microscopes, and other compact optical assemblies. However, the high level of dispersion associated with SF11 can result in chromatic aberration, where different wavelengths of light are focused at different points. To correct for this, SF11 is often combined with other glass types that have lower dispersion in complex lens systems, aiming to achieve balanced chromatic correction. Its unique properties make SF11 a popular choice in high-performance optics where both a high refractive index and specific dispersion characteristics are necessary. While SF11 is generally more expensive than more conventional optical glasses like BK7, its specialized attributes make it invaluable in advanced optical designs that demand high levels of performance.

## SF11 and similar glasses produced by different makers

Maker | Glass
--- | ---
Schott | N-SF11
Hikari | E-SF11
Sumita | K-SFLD11
CDGM | ZF13