eli5 Why do camera lenses need to focus on something? Why can’t they just render an image in which everything is clear?

Question

Or maybe only some types of lenses work like that?

In: 281

Answer 1

[Light field cameras](https://en.wikipedia.org/wiki/Light_field_camera) can do that, but sadly they are pretty niche. They achieve this by having a [microlens array](https://en.wikipedia.org/wiki/Microlens) inside, providing directionality. Here’s a (https://www.youtube.com/watch?v=rEMP3XEgnws) about how they work.