The world of glass can get confusing, but it's important to know the difference between flint and crown glass. Flint glasses have a higher refractive index than crown glasses, which makes them more transparent and allows them to transmit more light. Flint glasses also transmit a wider range of wavelengths than crown glasses—which means they're less likely to color your drink or distort the colors you see through them.
Flint glass has a higher refractive index than crown glass.
The refractive index is a measure of the speed of light through an object. It indicates how much the path of light is bent when it passes from one material into another, or from air into a denser material. Flint glass has a higher refractive index than crown glass (1.5-1.6 vs 1.5-1.6), which means that light travels more quickly through this type of glass than it does through crown glass; therefore, flint glasses produce sharper images than crown glasses do when looking at objects in them straight on or slightly off axis -- that is, not perfectly perpendicular to their faces.
Flint glass transmits a wider range of wavelengths than crown glass.
The refractive index of flint glass is higher than that of crown glass, meaning that it will transmit a wider range of wavelengths. This effect can be seen in the transmission spectrum curves.
Flint glass does not have bubbles like crown glass.
You can tell the difference between flint and crown by the way they are made. Flint is made from molten glass, whereas crown is blown into a mold to create its shape. Bubbles are caused when air gets trapped in the blowing process, so only certain types of flint will have them (like leaded crystal).
Flint glass has a lower dispersion than crown glass.
Dispersion is the ability of a material to separate white light into its constituent colors. It's measured in nanometers (nm), and the lower the value, the more highly-dispersive a material will be. For example, flint glass has a dispersion value of 7 nm; crown glass has an average dispersion value of 20 nm.
Learn about flint and crown glass to tell them apart!
Flint glass is a type of soda-lime glass that contains lead oxide and calcium fluoride. It has a higher refractive index than crown glass, which makes it more expensive to produce. Flint glass can transmit a full spectrum of visible light, while crown transmits only part of the visible spectrum.
Flint is also less likely to contain bubbles and impurities than crown due to its slower cooling rate during manufacture.
If you’re new to the world of glass and want to learn more about flint and crown glass, we hope this article has been helpful. Remember that both types of glass have their own unique benefits and applications—flint for its high refractive index, low dispersion and ability to transmit wavelengths; crown for its low dispersion, high transmissivity as well as bubble-free surface.