Frequency comb

A frequency comb is like a special kind of rainbow that scientists use to measure things really accurately.

You know how when you shine a light through a prism, you get a rainbow with all the different colors separated out? Well, with a frequency comb, you can make a rainbow of light that has not just colors, but a bunch of different frequencies too!

Think of it like different sound notes. Just like a song can have different notes like high or low, different colors of light can have different frequencies. The frequency comb helps scientists measure these different frequencies really accurately.

The way it works is kind of like a metronome that keeps really precise time. The frequency comb creates light pulses that come out super regularly like ticks of a clock. These pulses are made up of a bunch of different frequencies of light all packed really close together.

When scientists use the frequency comb to measure things, they compare the different frequencies of light to the ticks of a clock to get really precise measurements of how long different things take or how far apart they are. It’s kind of like using a ruler, but with light instead of measuring tape!