Back focal plane

The back focal plane is like a special spot in your camera or microscope. It's where all the light comes together after it goes through the lens or mirrors. Kind of like all the people in a playground going to one spot. That spot is the back focal plane. It's important because it helps make the picture or image clear and in focus. Think of it like putting together a puzzle. The back focal plane is where all the puzzle pieces come together to make a complete picture. So if you want to take a good picture or see something clearly, you need to pay attention to the back focal plane.