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Kyle M. Douglass

@kmdouglass.bsky.social
321 followers 75 following 114 posts

Researcher in Optics and Biophysics @ EPFL | Computational, Label-Free, and Fluorescence Imaging Specialist | Software Engineer kylemdouglass.com

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Kyle M. Douglass @kmdouglass.bsky.social · 15/09/2026
Today I heard someone describe an off-axis hyperbolic lens surface as "violently non-aplanatic." #optics #poetry
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Kyle M. Douglass @kmdouglass.bsky.social · 21/08/2026
I've been playing with PyTorch's autograd for only one week and already I lay awake at night wondering whether my latent variables are flowing differentiably through my inference chains. #everydayproblems
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Kyle M. Douglass @kmdouglass.bsky.social · 17/08/2026
#Radiometry is a challenging topic in #optics because the physics and the mathematics are often presented together as one subject, when in reality there is a clear delineation between the two. Here I provide a primer on the basic mathematics of radiometry. kylemdouglass.com/posts/a-prim...
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Kyle M. Douglass @kmdouglass.bsky.social · 07/08/2026
I added beam scanning capabilities to our lab's vector focal field simulation library just now: github.com/LEB-EPFL/jus... You can use it to simulate beam scanning using arbitrary vector beams in the focus of a high NA microscope objective.
github.com
GitHub - LEB-EPFL/just-focus: Vector electromagnetic field calculations in the focus of high NA microscope objectives.
Vector electromagnetic field calculations in the focus of high NA microscope objectives. - LEB-EPFL/just-focus
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Kyle M. Douglass @kmdouglass.bsky.social · 04/08/2026
I started a thread on Microforum searching for cameras similar to the Photometrics Kinetix and have shared a spreadsheet with my search results. If you know of others that fall within this category, then please do share. forum.microlist.org/t/equivalent...
forum.microlist.org
Equivalent cameras to the Photometrics Kinetix?
Thanks again @Hazen_Babcock . It’s a good point to look at the sensor itself. Here is the spreadsheet I compiled of similar cameras: Proton Drive The cameras I looked at were: Photometrics Kinetix...
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Kyle M. Douglass @kmdouglass.bsky.social · 29/06/2026
Last night I learned that the effective focal length of a lens can differ in the backward and forward directions if the refractive index of the media in object and image spaces differ. I think often about how little we treat this scenario in #optics education given its ubiquity in #microscopy.
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Kyle M. Douglass @kmdouglass.bsky.social · 11/06/2026
Is the infinity mark on cheap machine vision lenses always this wrong? This is the setting at which I'm able to focus on some clouds 🤔 Am I missing something? #optics #computervision
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Reposted by Kyle M. Douglass
reto @galactic-forensics.space · 10/06/2026
Do you write/want to write drivers to communicate with (scientific) instruments in Rust? Check out my latest blog post on how to make this hopefully easier in the future. Comments, ideas, etc. are always welcome. blog.galactic-forensics.space/blog/07-inst... #Rust
blog.galactic-forensics.space
instrumentRs v0.2.0 design ideas
Thoughts and ideas...
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Kyle M. Douglass @kmdouglass.bsky.social · 09/06/2026
You can place a mirror at 45 deg. AOI at the focus of a lens whose back focal distance is known by using a ruler with straight edge against the lens housing and extending beyond the mirror. Under collimated input, the intersection of the reflected beam with the ruler should be the BFD. #optics
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Kyle M. Douglass @kmdouglass.bsky.social · 02/06/2026
"What we saw was this pretty striking pattern that software engineers got about 20% more feedback if they were sitting near their colleagues than if they were distant from them... It was [young workers] who had the most to learn that really saw this deficit in feedback." www.npr.org/2026/06/01/n...
npr.org
Remote work -- not AI -- has sidelined recent college graduates, research finds
Research from the New York Fed finds that younger college graduates have been sidelined by remote work in recent years, as companies may be reluctant to hire those needing more training and mentoring.
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Kyle M. Douglass @kmdouglass.bsky.social · 18/05/2026
Using a wavefront sensor and bisection to place the focal plane of a microscope tube lens in the back focal plane of an objective lens. I used beam diameter as the readout because the radius of curvature did not change significantly over the range of lens positions that I tested. #microscopy
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Kyle M. Douglass @kmdouglass.bsky.social · 10/05/2026
I'm still trying to work out whether this is truly useful, but you can use a coverslip to pick off the beam from an alignment laser that is back reflected from a mirror at the end of a setup (not shown). Deviations of the beam upon insertion of a lens indicate its misalignment. #optics
An optical table to which posts are attached. At the end of each post is an optical element or device. An alignment laser launches beam through a glass coverslip angled at 45 degrees to the beam's axis. The coverslip reflects the backreflected beam into the direction of the camera.
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Kyle M. Douglass @kmdouglass.bsky.social · 08/05/2026
I added a galvo and scan lens example to my Cherry ray tracer to help one of our PhD students understand scan systems. Click and drag on the theta rotational offset value for the first mirror surface to see what happens to the ray fan in real time. #optics #microscopy kmdouglass.github.io/cherry
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Reposted by Kyle M. Douglass
Eugene Katrukha 🇺🇦 @ekatrukha.bsky.social · 30/04/2026
After 9 years, I am finally finishing the story about normalized cross-correlation (and reviving my blog). The new blog post about deep technical details on the most used image registration technique. I know y'all have been waiting. katpyxa.info/feedbacks/?p...
katpyxa.info
Calculating normalized cross-correlation (part 3) – //><=~!=//
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Kyle M. Douglass @kmdouglass.bsky.social · 22/04/2026
"[I]n any science less complete than physics, the more general mind still has its uses, though everyday the chances grow less." C. P. Snow, lamenting the loss of synthesis within a science as it matures.
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Kyle M. Douglass @kmdouglass.bsky.social · 10/04/2026
When a single line of code you wrote without thought three years ago leads to three weeks of nightly debugging after the kid goes down. Ray-Surface Intersections with the Newton-Raphson Algorithm kylemdouglass.com/posts/ray-su...
kylemdouglass.com
Ray-Surface Intersections with the Newton-Raphson Algorithm
I take a deep dive into computing ray-surface intersections using the Newton-Raphson algorithm.
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Kyle M. Douglass @kmdouglass.bsky.social · 26/03/2026
An apologia for theoretical biology. From "Energy Flow in Biology" by Harold J. Morowitz.
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Kyle M. Douglass @kmdouglass.bsky.social · 19/03/2026
"Optimal lens design and use in laser-scanning microscopy" doi.org/10.1364/BOE.... #optics #journalclub
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Kyle M. Douglass @kmdouglass.bsky.social · 18/03/2026
I implemented folds into the Cherry Ray Tracer today. Rather than freely placing components in space, I took inspiration from video games and used a RUF coordinate system to build up the system surface by surface. kmdouglass.github.io/cherry kylemdouglass.com/posts/3d-seq... #optics
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Kyle M. Douglass @kmdouglass.bsky.social · 17/03/2026
Does anyone have any tips for putting a galvo in the center of a 4f system in the scan/descan arm of a laser point scanning fluorescence microscope? I normally align everything to the objective, but here I wonder whether the galvo should be the primary datum to align to.
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Kyle M. Douglass @kmdouglass.bsky.social · 13/03/2026
I can never remember the electrostatic conventions for the mitochondrial membrane potential, so I wrote them down: kylemdouglass.com/posts/electr...
A sketch the interior of a mitochondrion with cristae, inner, and outer membranes. A simplified voltmeter shows a value of -150 mV. The positive probe is in the matrix, and the negative probe is in the intermembrane space. IMM, IMS, and OMS labels indicate the inner mitochondrial membrane, intermembrane space, and outer mitochondrial membrane, respectively.
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Kyle M. Douglass @kmdouglass.bsky.social · 12/03/2026
I finally managed to rewrite the Cherry Ray Tracer GUI using egui, an immediate mode GUI for Rust with WASM support. In addition, I figured out threading in WebAssembly via SharedArrayBuffers, so this thing is now lightning fast. kmdouglass.github.io/cherry #optics #wasm #raytracing
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Kyle M. Douglass @kmdouglass.bsky.social · 26/01/2026
Last week I learned that I can use the internal counter on a NI-DAQ board as a triggerable pulse sequence that serves as the clock for an analog output waveform. Pretty cool! #microscopy kylemdouglass.com/posts/trigge...
kylemdouglass.com
Triggering Analog Voltage Outputs using a NI-DAQ Counter
I explore routing signals from counters on a NI-DAQ device for custom triggering and waveform generation.
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Kyle M. Douglass @kmdouglass.bsky.social · 13/01/2026
I finally got around to writing the discussion section of our lab's basic training course on live cell #microscopy. I explain the tradeoffs involved in designing an imaging experiment and the art of thinking of the experiment as an optimization problem. leb-epfl.github.io/basic_traini...
leb-epfl.github.io
Introduction - Microscopy Basic Training
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Kyle M. Douglass @kmdouglass.bsky.social · 13/01/2026
I had the happy realization the other day that conservation of radiance / étendue is purely geometrical. Radiance is just proportional to the size of the set of all lines through two area elements, and the product of area and solid angle is an invariant over this set. #optics #radiometry
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Kyle M. Douglass @kmdouglass.bsky.social · 22/11/2025
A holiday demonstration of the different penetration depths of red and blue light into tissue. #optics
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Kyle M. Douglass @kmdouglass.bsky.social · 18/11/2025
When X-rays are incident upon a crystal, some of their energy is reflected from the lattice planes. Certain angles of incidence will lead to the observation of diffraction peaks due to constructive interference between the reflected wavefronts. #optics #microscopy youtu.be/FZ4gilAe7x0
youtu.be
The Bragg Condition
YouTube video by Kyle Douglass
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Kyle M. Douglass @kmdouglass.bsky.social · 20/10/2025
The construction of the support of the 3D aperture (a.k.a. the optical transfer function or OTF) using the Ewald sphere in a brightfield microscope under partially coherent illumination. #optics #microscopy
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Kyle M. Douglass @kmdouglass.bsky.social · 14/10/2025
How to use the Ewald Sphere to determine the support of the 3D aperture of a brightfield microscope under coherent illumination. #optics #microscopy
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Kyle M. Douglass @kmdouglass.bsky.social · 09/10/2025
Object models for image formation theory in brightfield microscopes. kylemdouglass.com/posts/image-...
kylemdouglass.com
Image Formation in Brightfield Microscopy: Part 1 - Object Models
I describe how objects are treated in image formation models for brightfield microscopy.
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Kyle M. Douglass @kmdouglass.bsky.social · 03/10/2025
I spent the morning playing with GeoGebra for the first time and, along the way, published an app about aligning a laser beam to an axis in space defined by two irises using two rotating mirrors. There's a learning curve, but it's not too bad. #optics www.geogebra.org/m/tfrykp7y
geogebra.org
Alignment with Two Mirrors
Aligning a laser beam to an axis in space using two mirrors.
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Kyle M. Douglass @kmdouglass.bsky.social · 25/09/2025
Check out my dope new fixed focal length lens.
A Thorlabs cage rod system consisting of a Flir camera and 200 mm microscope tube lens on a photography tripod.
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Kyle M. Douglass @kmdouglass.bsky.social · 23/09/2025
It's kind of nuts that most of the cost of kinematic #optics mounts usually covers the alignment phase of a setup, after which the mount serves the same role as an unmovable piece of stock metal.
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Kyle M. Douglass @kmdouglass.bsky.social · 14/09/2025
Trying to get a sense of how much current I can pass through salt water and happened to observe electrolysis by accident.
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Kyle M. Douglass @kmdouglass.bsky.social · 05/09/2025
Do any of you fellow #optics nerds know whether First Contact solution will remove residue from alcohols left behind on glass?
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Kyle M. Douglass @kmdouglass.bsky.social · 12/08/2025
The more I learn about floating point arithmetic, the more I am impressed that scientists can get anything done at all on a computer.
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Kyle M. Douglass @kmdouglass.bsky.social · 07/08/2025
Pro-tip: you can use the hole in a Thorlabs FC/PC fiber mount to self-center a domed LED when gluing it to a cage plate blank. #optics
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Kyle M. Douglass @kmdouglass.bsky.social · 06/08/2025
This week I wrote a small Python library for computing vector EM fields in the focal region of high NA objectives. github.com/LEB-EPFL/jus... I'd be pleased if would try it out and leave any feedback or bugs in the issue tracker. :)
github.com
GitHub - LEB-EPFL/just-focus: Vector electromagnetic field calculations in the focus of high NA microscope objectives.
Vector electromagnetic field calculations in the focus of high NA microscope objectives. - LEB-EPFL/just-focus
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Kyle M. Douglass @kmdouglass.bsky.social · 30/07/2025
> So Lemkin's attempts to communicate with the AI model... were fundamentally misguides. Maybe the real, lasting value in LLMs is that they have brought fundamental questions about cognition from scientific specialty to the working lives of everyday people. arstechnica.com/information-...
arstechnica.com
Two major AI coding tools wiped out user data after making cascading mistakes
“I have failed you completely and catastrophically,” wrote Gemini.
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Kyle M. Douglass @kmdouglass.bsky.social · 08/07/2025
I've resorted to printing out code and checking it by hand just to validate AI slop. #thefutureisnow
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Kyle M. Douglass @kmdouglass.bsky.social · 07/07/2025
Can anyone recommend a service where I upload 3D models of simple machine parts and they mail me the CNC'ed results? Something like Osh Park that does small batches but for machine parts? I feel like I saw something about this recently but can't remember which platform I saw it on.
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Kyle M. Douglass @kmdouglass.bsky.social · 07/07/2025
Here's a short post about converting the surface sag of a class of common optical surfaces into the normal form of a quadric. The trick is to use a method from high school #math that doesn't get as much attention as, say, the quadratic equation or the FOIL method. kylemdouglass.com/posts/comple...
kylemdouglass.com
Completing the Square and the Normal Form of Quadrics
I explain how to convert the expression for the sag of an optical surface into the normal form of a quadric equation.
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Kyle M. Douglass @kmdouglass.bsky.social · 04/07/2025
You know you're f***ed when the Wikipedia article on the problem you're working on only exists in one language and it isn't English. de.m.wikipedia.org/wiki/Umrissk...
de.m.wikipedia.org
Umrisskonstruktion – Wikipedia
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Kyle M. Douglass @kmdouglass.bsky.social · 25/06/2025
I'm brushing up on my computational #geometry skills and found this great resource for surface representations: "Representing Smooth Surfaces" by Ken Takusagawa Fun fact: surface sag in #optics is just an explicit surface representation. groups.csail.mit.edu/graphics/cla...
groups.csail.mit.edu
Representing Smooth Surfaces
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Kyle M. Douglass @kmdouglass.bsky.social · 23/06/2025
I realized recently that I have always taken for granted the fact that camera read noise is Gaussian, but I never questioned why this is. The answer, I think, is due to the central limit theorem. #optics #imaging kylemdouglass.com/posts/why-is...
kylemdouglass.com
Why is Camera Read Noise Gaussian Distributed?
I investigate why camera read noise may be modeled as a Gaussian random variable.
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Reposted by Kyle M. Douglass
SPIE @spie.org · 17/06/2025
This month's Henry Poincare Webinar Series on Optical Polarization and Related Phenomena will be led by Aristide Dogariu! 💡 Join us on 24 June for this presentation on light polarization and the statistical properties of the electric field vector.⚡ Register here: spie-org.zoom.us/web...
Promotional graphic for an SPIE Online Poincaré Webinar featuring Aristide Dogariu from Central Florida / CREOL on "Polarization and polarimetry," scheduled for June 24, 2025, at 6:00 AM PDT. The background is a blurred abstract red design, and there is a photo of speaker Aristide Dogariu in the center.
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Kyle M. Douglass @kmdouglass.bsky.social · 05/06/2025
I did a deep dive into the mathematics for 3D optical system design software, focusing on ways that we can make layouts more intuitive. I hope you find it as interesting as I did in writing it. #optics kylemdouglass.com/posts/3d-seq...
kylemdouglass.com
3D Sequential Optical System Layouts
I describe the geometry involved for laying out sequential optical systems in 3D.
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Kyle M. Douglass @kmdouglass.bsky.social · 30/05/2025
Sometimes you come across a site and you just have to instantly bookmark it. Mathjax examples for easy copying and pasting: easy-copy-mathjax.nakaken88.com/en/matrix/
easy-copy-mathjax.nakaken88.com
Matrix | Easy Copy Mathjax
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Kyle M. Douglass @kmdouglass.bsky.social · 28/05/2025
Claude, you cheeky little troublemaker.
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Kyle M. Douglass @kmdouglass.bsky.social · 26/05/2025
One piece of advice I have for people living in Switzerland is to always stay grounded.
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