Étiquette : physics

How do big telescopes look through the atmosphere – Adaptative Optics 101

Mario Tonin0 commentaire

Continuing my series of post covering my talk from last Christmas about the use of lasers in space and astronomy. The topic today is adaptative optics. I’ll explain the reason why we need it, and how it works in simple terms. Enjoy. No surprise: telescopes are the main tool of astronomers. Since Newton, we have built countless telescopes of various sizes and shapes. And lately, we even send them to space. We have Hubble, the JSWT for the more famous, and a lot of other space telescopes less known. But why sending them to space? After all, space is difficult. …

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Laser physics: gain medium and population inversion

Mario Tonin0 commentaire

Continuing the series on lasers. In the first part, I went fast over plenty of concepts and left others on the side because they were not necessary to get a global understanding of lasers. Here, I want to get a little deeper in some specific concepts. I want to talk more in details about the gain medium of a laser and why population inversion is a vital concept. For now, I have been relatively simple on the gain medium characteristics… I have considered a simple material with two atomic energy levels, and I have been assuming that the transition is …

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Checking dimensions in equations

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Short post this week. I want to talk about a simple concept that is extremely useful in physics and other fields of applied science. Especially those fields working with equations to calculate anything that has a physical meaning to it, like a speed, a voltage, a weight.. As a physics student, our teachers would usually spend a few minutes talking about how it is extremely important to check dimensions. Back then, I was listening and not really thinking how that would help me concretely to find the answer to the problem they were giving us. I would always be puzzled …

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An introduction on laser physics

Mario Tonin0 commentaire

So I want to start a series of posts that will focus mostly on lasers, what they are, how they work, what are the most important elements, etc… It can still evolve. Some prerequisites first: To fully understand what I will write, here, it definitely helps to be familiar with a few concepts and bases from electromagnetism and optics, obviously. I’ll try to explain these concepts along the way of course. Nevertheless, even if you don’t have the necessary background, keep reading. I’ll try to keep it simple and limit the mathematics to a minimum. It’s no surprise that lasers …

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