博文

目前显示的是 十月, 2022的博文

What Are Lenses for?

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  Lenses are everywhere in the world around us - everything from car headlights and flashlights to the LED lights used in electronic dashboards.   Our eyes may contain the most amazing lenses. Think about what happens when you look at the world around you. One minute you're staring at the ground in front of your feet. A few seconds later you hear a plane whizzing by, turn your head and watch it fly by. Do this trick with a pair of binoculars and you will find that it takes you a long time to adjust your focus from near (looking at the ground) to far (looking at the plane). Try it with the naked eye and you won't even notice what you're doing. That's because your eyes have  flexible lenses , controlled by tiny muscles that project outward and change shape instantly to focus on anything from fingerprints on your fingers to the surface of the moon. How amazing is that? Custom MgF2 Coated Achromatic Lenses   A variety of lenses We all have  lenses  in our eyes, but many of