Optical clock

An optical clock is a super special and very fancy type of clock that measures time very precisely using light. It's kind of like a regular clock but instead of counting hours, minutes, and seconds, it counts something called "oscillations".

Now, oscillations are patterns that happen over and over again - like when you swing on a swingset, you keep going back and forth in a pattern. Well, in an optical clock, there's a special type of light that goes back and forth really fast between two mirrors, and scientists can count how many times that light goes back and forth - that's an oscillation!

But why is counting oscillations important? Well, when we know how many oscillations happen in a certain amount of time, we can use that to measure time really accurately. And when I say accurate, I mean really, really accurate - even more accurate than the regular clocks we use every day!

So, an optical clock is an amazing tool that scientists can use to help them understand how time works and to make super precise measurements. It's like having a magic watch that tells time way better than any other watch on the planet!