Relay lens

Okay kiddo, so you know how when you look through a magnifying glass, things look bigger? Well, a relay lens is kind of like a magnifying glass, but it's used in cameras and microscopes to make the image sharper and clearer.

Here's how it works. When light comes into a camera or microscope, it needs to pass through several lenses before it reaches your eye or the camera sensor. But sometimes, the light can get all jumbled up and make the image blurry or distorted.

That's where the relay lens comes in. Its job is to take the light from the first set of lenses and "relay" it to the next set of lenses, but in a way that makes the image much clearer. Think of it like a messenger who takes a jumbled message and then delivers it in a way that makes sense.

So when you look through a microscope or take a picture with a camera, the relay lens is working hard behind the scenes to make sure you can see things clearly. Pretty cool, huh?