This is technically known as a catadioptric lens and has an unusual construction of mirrors and lens elements. As well as glass elements there are mirrors at the front and rear to fold the light as it ...

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For hundreds of years, the principle behind the telescope has been as simple as it gets: build a lens or mirror to collect a large amount of light, focus that light onto a detector (like an eye, a ...

We've learned about light and how to bend it to our will. But what can we LEARN from it? Light is everywhere … but it’s not as predictable as you might think. It’s a wave that travels in straight ...