Prismatic Miku

"Objects for diffraction." Practical exercises in light. 1914.

Internet Archive

Small Scale Length Measurements

Many different techniques to measure length at small scales (typically microns to nanometers), including X-ray diffraction/crystallography, electron microscopy, and atomic force microscopy, among others. X-ray diffraction can be used to measure atomic spacing and lattice parameters (thereby determining crystal structure) using the wavelengths of the X-rays in question. Electron microscopy differs from many other techniques because they use, as the name implies, electrons to make their measurements, rather than any form of light. Though electrons are reflected back to a detector, the transit-time is not used to make measurements. Instead, Fourier transforms are used to generate an image.

Sources/Further Reading: (Images 1 and 4 - XRD Wikipedia) (Images 2 and 3 - SEM Wikipedia) (Measuring Length Wikipedia) (University of Wisconsin-Madison XRD) (University of Pennsylvania XRD) (University of Colorado XRD) (SEM Book Chapter)

sometimes you run into something that just overturns your understanding and builds a new, more coherent picture. this is one of them.

they taught us about diffraction theory at uni - Fresnel, Fraunhofer all of that, we did experiments with lasers - but it never occurred to me to analyse lenses in terms of diffraction. it makes so much sense now! i was never entirely satisfied by the ray approximation to light, so seeing what's really going on in the lightfield and how you can use a diffraction plate as a lens, with each ring contributing higher order Fourier terms to the image, is like. crazy cool.

꧁★꧂

Have you ever marvelled😲 over those 3D projections in sci-fi movies? 🤔How many times could you tell the difference between real and fake 🥸 when you saw these holographic displays ? Of course, the reality of how holograms work isn't quite as flashy ⚡ as Hollywood portrays. But that doesn't make it any less fascinating! Tap & swipe ➡️ through this post to decode the science behind them.

Icosahedron net - "coiling up"

This icosahedron net is really cool, as it is just like a "string of triangles" you can just roll up to form the icosahedron.

Result:

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The hexagon grid is really helpful for drawing equilateral triangles.

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It reminds me of this:

Diffraction - Source: German PDF [found at TU-dresden website]

...

Metamorphestra of entangled states of a life's unfolding and reshaping process - shapeshifting of the shapeshifter

[2023/09/24]

🌈🌚🌞 Moment of totality through diffraction grating Spectral deconstruction of total solar eclipse - 16x speed boomerang for generation hyper deficit (audio)Laxcity-landing/homesick #totality #solareclipse2024 #solareclipse #solareclipseglasses #eclipse #sun #moon #rainbow #art

DAY 394 - F

Feeling festive!!

This is my latest piece of physics-inspired art, called "Diffracted Surge in the Negative"

It is part of a recently started series called "Not Connecting the Dots"

I have inverted the spectral colors of the rainbow - and I still like it! Way better than any "random" combination of colors I tried! Perhaps there are aliens out there whose eyes conceive our world in colors like this?

More on my blog here:

X-ray lasers: Why does brighter mean darker?

When we illuminate something, we usually expect that the brighter the source we use, the brighter the resulting image will be. This rule also works for ultra-short pulses of laser light—but only up to a certain intensity. The answer to the question why an X-ray diffraction image 'darkens' at very high X-ray intensities not only deepens fundamental understanding of the light-matter interaction, but also offers a unique perspective for the production of laser pulses that have significantly shorter pulse duration than those currently available. The more light, the brighter? This observation might sound trivial, were it not for the fact that it is not always true. When silicon crystals are illuminated with ultrafast laser pulses of X-ray light, the resulting diffraction images are indeed initially brighter the more photons fall on the sample, i.e., the higher the beam intensity. Recently, however, a counterintuitive effect has been observed: when the intensity of the X-ray beam starts to exceed a certain critical value, the diffraction images unexpectedly weaken. This puzzling phenomenon has just been explained, thanks to the efforts of the experimental and theoretical physicists from Japanese, Polish and German research institutions, including the RIKEN SPring-8 Centre in Hyogo, the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow and the Center for Free-Electron Laser Science (CFEL) at the DESY laboratory in Hamburg.

Read more.

space bubble

90 days of productivity

Day 49/90

With @academiawho and @docta1228

6th November 2023, Monday

No classes today though fest ended yesterday.

Again, chill day. Woke up at 7.

Pretty colourful day huh

Watched one c programming video.

Did some gen bio notes.

Did some trigonometry.

Made a formula sheet for gen physics chapter.

Wanted to slap whoever discovered engineering graphics.

Had all 3 meals 🥰

ALSO DID MY LAUNDRY (PROUD OF MYSELF 🤧😤)

Marseille, Montredon, chez moi . De ma fenêtre, les couchers de soleils sont superbes (...mais parfois aussi les "entrées maritimes" : air trop chaud, mer trop fraîche...)

Alors l'avant-dernière est une sorte de diffraction que fait ma fenêtre sur mon mur !

Quant à la dernière...problèmes de remontée lymphatique, nécessitant ces bottes gonflables ultra sexy !