What is the refractive index of crown glass?

The refractive index of crown glass is indeed around 1.523. This value is important because it reflects the degree to which light is bent or refracted when passing through the glass. Crown glass, commonly used in optics and eyewear, has a relatively low refractive index which makes it suitable for certain lens applications, particularly where clarity and optical quality are essential. The refractive index can affect the design of lenses and their ability to focus light effectively, impacting the overall performance of optical devices such as eyeglasses and cameras.

Other values provided in the question correspond to different types of glass or materials; for instance, lower or higher refractive indices may pertain to types of plastic or specialized glass used in high-index lenses, which would have distinct optical properties and applications. Understanding the specific refractive index of crown glass allows opticians to make informed decisions about lens material for different visual needs.