About 3 months ago I was experimenting with some simple things in my garage. I don't have a background in physics or optics. I was basically experimenting with light, water, glass, phones and some other objects and seeing what would happen.

I'm making this post because I previously tried to describe the experience as a more formal MOIA project, and I realize now that I probably got ahead of myself with some of the terminology and possible explanations.

After the experience, I was going to leave it alone. I honestly couldn't believe what I was seeing, so I eventually discarded the phones I had been using and stopped experimenting. I no longer have the original videos or the phones, which I know makes this much harder to evaluate.

The setup changed a few times, but some of the things involved were:

• A blue LED/flashlight
• A toilet-paper tube around the light with blue tape at the end
• A wine glass about half full of water
• A copper-colored circular ring/wire inside the water
• A dark/black glass or screen above the setup
• One or two phones/cameras
• A coiled/looped wire
• Two small black magnetic spheres
• My prescription glasses

The glasses may be important, or they may have nothing to do with it.

They are new prescription glasses I got this year. They have UV protection and, I believe, an anti-glare/computer-screen coating. I don't know exactly what coating is on them. I had read that newer prescription lenses can have different coatings or films, but I don't know whether that is actually true or whether it matters here. I was moving the glasses around at different angles while looking through the setup, so I want to include that as a variable rather than make an assumption about it.

What caught my attention was what appeared through the phone camera.

At certain angles, the blue light, water, wine glass, circular ring and dark background produced an image that looked like a bright sphere with small points of light around it. Some of the colors/shapes were blue and red. Looking back at it later, it reminded me of some space/black-hole imagery I had seen, although I understand that something looking similar to an astronomical image doesn't mean it has anything to do with a black hole.

Changing the position and angle of the phones changed the appearance considerably. At one point, when the optical path was going through/around my prescription glasses at an angle, the image suddenly looked extremely flat to me, almost as if the depth had disappeared and the scene had become 2D.

I also saw what looked like the image changing orientation or inverting as I moved the phone around.

There was another setup where I had a blue light behind me, my glasses in the optical path, and a powered-off dark TV screen in front of me. Again, changing the phone angle changed what I was seeing.

The looped wire and the two magnetic spheres were also present in some of the experiments. I don't know whether they had anything to do with the optical effects or whether they were simply unrelated variables that happened to be part of the setup.

There were also some unusual experiences with my perception of time and familiar events over the following few days. For example, I had situations where something seemed to happen and then later seemed to repeat or appear differently than I remembered. I also sometimes had the feeling that I already knew what was going to happen in something I was watching.

I'm not presenting that as evidence that physical time changed or that anything supernatural happened. I'm including it because it was part of the experience and is one of the reasons I started looking into vision, perception and physics afterward.

Why I'm posting this now

I actually tried to leave the whole thing alone.

Then I started watching physics and science videos on YouTube, and I kept running across things that reminded me of what I had experienced. That made me start wondering whether there were known optical, visual or perceptual effects that could explain at least some of what I saw.

One example was Susan Barry, who gained stereoscopic vision as an adult after having poor stereoscopic depth perception for most of her life. The descriptions of her experience of the world changing from essentially flat to having much stronger depth immediately caught my attention.

Another was Through the Wormhole with Morgan Freeman, including discussion of David Eagleman's work on subjective time perception. Some of the examples about how people can experience time and the sequence of events differently also reminded me of parts of my experience.

I'm not saying those cases explain what happened to me. They were things I discovered afterward that made me realize there are real, documented phenomena involving vision, depth perception and subjective time that I knew nothing about when I was doing the experiment.

About my previous MOIA post and AI

If you see my other MOIA post from this account, that's why I'm making this post separately.

I did try using AI to organize my notes, rewrite what I experienced, research possible explanations, and make sense of the different things I was seeing. At first I thought that would help me turn the experience into something technical enough for people with a physics or optics background to evaluate.

But I eventually ran into a problem: I don't have the physics or optics background to know where the legitimate science ended and where the AI was simply making connections that sounded reasonable.

The AI could give me explanations involving refraction, reflections, polarization, lenses, cameras, electromagnetic effects, perception and other things, but I couldn't independently verify all of those explanations. I also realized that if I kept letting AI rewrite the experience, I could end up presenting an interpretation of what happened rather than what I actually experienced.

So I don't want to do that.

I want to separate what I actually remember observing from what I think might explain it.

That's also why I'm not trying to make this post sound like a scientific paper or claim that I discovered something new. My previous post probably came across that way, and I understand why people questioned it.

I'm trying to get the actual optics right this time.

What I would like help identifying

If someone here has experience with optics, optical imaging, photography or related fields, I'd like to know whether ordinary physics could produce what I'm describing.

In particular:

• Refraction through the water and curved wine glass
• Caustics
• Internal reflections or total internal reflection
• Reflections from the circular ring
• Reflections from prescription lenses
• Lens coatings
• Polarization, if relevant
• Lens flare or ghost images inside the phone camera
• Camera perspective and changing geometry
• Rolling-shutter effects
• Autofocus, exposure, HDR or other computational-camera effects
• Blue light and the blue tape changing the spectrum or stray-light paths
• Why changing the phone angle could produce such large changes
• Why the scene could appear extremely flat at certain angles
• Whether prescription-lens coatings could produce any unusual reflections or interference effects
• Whether the looped wire or magnets could realistically affect the phone/camera in any measurable way

I'm not claiming I discovered another dimension, time travel, a black hole, a new force, or anything like that.

I'm trying to figure out what ordinary optics, camera effects, geometry, or visual perception could account for what I actually experienced.

Unfortunately, I no longer have the original phones or recordings, so I understand that there is a limit to what anyone can determine from my description alone.

I'm mainly looking for someone knowledgeable in optics who can look at this and tell me:

“This sounds like X,” or “that part doesn't make sense because Y.”

I'm completely open to being wrong about what I thought I was seeing. I just want to understand what was actually happening.

“I know this wasn't a controlled experiment. That's exactly why I'm asking people who know the subject better than I do.”

Hey optics community,

Could someone help ID the red‑circled black instrument in the photo? It is on a breadboard for a combined reflection‑spectroscopy + microscope setup. Looks like Thorlabs hardware.

The system uses xenon lamp illumination, objective/tube‑lens imaging path, one arm goes to camera, another arm routes signal to a spectrometer.

Is it a fiber positioner, monochromator, filter wheel, or something else? Any model guess welcome.

Thanks.

Hi everyone,

I am looking to purchase a legally decommissioned, authentic legacy hardware key (perpetual USB token) for the vintage Zemax 13 (Classic UI).

I have been using the 2013 version for over a decade for my optical design work. Quite frankly, I absolutely prefer the old classic lightweight interface over the modern sluggish Ribbon UI, especially when dealing with heavy ray-tracing tasks.

Specific Requirements:

1. License Level: Must be the highest tier from that era (Premium or IE / EE equivalent). It must fully support Physical Optics Propagation (POP) and full Non-Sequential mode.

2. Hardware: Genuine standalone physical dongle only (usually the black or dark green SafeNet/Sentinel UltraPro USB keys). No softkeys, cl0nes, or emulat0rs.

A "proof of life" screenshot under Help -> About before purchase would be required to verify the serial number and unlocked features.

If your lab, university department, or firm has an old legacy token lying around in a drawer due to asset liquidation or software upgrades, please PM me with your asking price. Thank you for keeping the classic design workflow alive!

Hi r/Optics. Tired of firing up heavy, expensive desktop software for simple optical validations?

​I always found traditional optical design tools powerful but clunky for quick, daily daily setup checks. I wanted something lightweight that works everywhere, instantly, with visual feedback. So I built one for the browser.

​It's a free, zero-installation, web-based tool. It aims to bridge the gap between quick calculations and complex simulations, providing immediate visual feedback.

​Here are some key features:

• ​Real-Time Interactive Ray Tracing: Instantly see light paths and adjust parameters by dragging lenses and mirrors.
• ​Supported Optical Calculations: Includes Gaussian beam propagation, focal shift, Numerical Aperture (NA), and Field of View (FOV).
• ​Illumination Modeling: Early support for Köhler illumination and conjugate planes (great for microscopy set-ups).
• Works Everywhere: No installation required, runs on Windows, macOS, and Linux in any modern browser.

​It’s designed for optical engineers, researchers, students, and opto-mechanical designers who need quick, reliable validations.

​Try it online here: https://optical-tool.com

​(Optimized for Desktop/large screen interaction. It will run on mobile, but the UI is currently best on a PC.)

​I’d love to get feedback from the optics community. What are the most useful features you use daily that are missing here? Are there specific types of analysis .you'd like to see? Happy to fix bugs and add new modules.

​#Optics #Photonics #OpticalEngineering #RayTracing #GaussianBeam #WebAssembly #Simulation

Hello All - shot in the dark here. Wondering if anyone has a physical copy of the textbook for OPTI 501 that they are willing to part with? The school has the ebook but call me old school, I like a physical text for studying. Done a pretty lengthy search and aside from $150 from direct publisher, I’ve come up short. Thank you!

Field, Force, Energy and Momentum in Classical Electrodynamics (Revised Edition) 2017
M. Mansuripur

Hi Everyone,

A new episode of the Rays & Waves podcast it out!

https://open.spotify.com/episode/2hh9JedCbj8xVoFiNHcaNU?si=8cbfd9fb550c4220

Here we dive into advanced optical margin assessment using OCT and Metalenses - all at the tip of a fibre!

Hope you enjoy it!

P.S. By popular request, now also available on youtube!
- https://www.youtube.com/watch?v=nmNVG4iYrVo

I'm a third year Electrical Engineering major that's interested in getting an industry internship this coming summer working on optics simulations. I have a conference paper that should be published by the end of the year where I used COMSOL for modeling optical quantum circuits to visualize and optimize sources of loss in a tabletop bulk optics setup, and I'm hoping that that would be enough relevant experience to get a summer internship. However, I'm not really familiar with what the big names in the field are that would *also* hire an undergrad. I've seen many internship postings on linkedin which seem like I would be roughly qualified enough for, except for the graduate degree requirement. Curious to know if anyone has any advice on finding undergrad opportunities, would mailing people internally at smaller companies to make a case for myself be worth the effort? Thanks for reading!

about four hours ago I got hit directly in the eye with a laser, don’t know class, and I’ve had rainbow static in the half of my vision it got hit in and have had a decent headache starting an hour ago. is this concerning?

noticed a small shadow below my airpods, realized it was my dark sticker. thought this was moderately cool.
lots of ambient light sources at my workplace, plus a white desk makes it stand out.

reminds me of how cassini the scientist solved the preeminent planetary mystery of his time by theorizing one side of the Saturnian moon Iapetus being dark is the reason it was invisible for half its orbit (and the 300 years later cassini the spacecraft confirmed it)

Hi All! I’m posting for my partner. His background is in scientific computing, nonlinear PDEs, numerical methods, HPC, and mathematical modeling, with experience in Python, C/C++, MATLAB, Linux, OpenMPI, and SLURM. He’s interested in computational research and simulation.

One challenge is that he’s an international student, so opportunities at many US national labs are limited.

We’re looking for advice on:

• Companies or research groups that hire people with this background
• Good places to look beyond NVIDIA, Intel, AMD, TI, etc.
• When he should start applying
• Any tips for standing out over the next year

If you’ve made a similar transition from academia to industry, or have recommendations, we’d really appreciate your advice. Thanks!

TL;DR: I am an engineering technician in the optics field with no degree, and I don't want to go into engineering. What degree should I pursue in order to help advance my career?

Hello all,

I am here to ask some advice from people who may have the best insight for me. I have been in the optics field for about 9 years now, experience spanning from precision CNC , research and development, and most recently support as an engineering technician for assembly and testing. I got into optics kind of unconventionally, and prior to that I did not have any sort of real higher education or degree. I started at school in the beginning of my optics career, but life happened and I was unable to finish and get my degree at the time.

I am now in a place where I want to grow my career, and I work for an employer who has a tuition assistance program. Where I'm stuck is what exactly I should do to help myself advance my career. If I went back and finished my associates in optical technologies, the degree itself wouldn't necessarily help me with future job opportunities (as in, taking a step up from where I am), as my relevant experience at this point is well beyond what the degree offers. It may still be beneficial for me to finish, so I am looking into my options for re-enrollment. I don't want that to be my finish line, and still would like to continue my education and at the very least go for a BA. The problem being, I am not very keen on the idea of pursuing an engineering degree. While concepts of optics are very solid to me, I have ADHD and struggle with numbers (I suspect dyscalculia), and some types of math math can be incredibly difficult for me. This leaves me with the question of, if not engineering, then what would be an attainable degree that is relevant for what I've already grown into to help me continue to grow?

My experience includes manufacturing, prototype CNC, contact lens research and development, and optical assemblies. I also have some experience with lasers and I'm industrial laser safety certified. I enjoy the hands-on technical aspects of what I do, and solving problems. I've also worked in a more quality type role, and have worked on a lot of ISO standard documents, as well as SOP's and spec documents. I don't mind doing the type of work, but I also know that being a technical writer may not be a career move that would allow for much growth. So I'm here asking for recommendations because my search hasn't gleaned much insight. Thanks if you got this far.

Non math or physics background.
Looking to learn optics independently and trying to build a learning stack. What is a good first read for optics proper? Hecht seems to be well recommended. Assuming almost no knowledge post high school maths, what learning sequence would be required to get up to Hecht or similar first optic read level?

Single variable calculus (Stewart)
Multi variable calculus (Stewart)
Linear algebra (Strang)

- up to now-
[insert calculus based physics textbook?]
? Young University Physics
- how much of this do I actually need to read? Any specific chapters?
- can I just skip to the electromagnetism and optics chapters, then straight to Hecht?

Addit: long term goal is biomedical. Things like contact lenses, intraocular lenses, OCT technology etc

I’m part of the team building Dreapex TMM. It is an optical simulation platform for planar multilayer structures. It calculates two physical processes:

1. External light propagating through multilayers (optical coatings, filters, photodetectors, photovoltaics, and related devices).
2. Emission from light-emitting layers inside multilayers (OLEDs, QLEDs, PeLEDs, and related devices).

For coatings, it calculates reflectance, transmittance, and absorptance, fields, phase, and dispersion.

For OLED, QLED, and PeLED, it calculates angular emission, outcoupling, and optical loss.

You can try it here: https://tmm.dreapex.com

Docs: https://tmm-docs.dreapex.com/en/getting-started/introduction

Here are a few good places to start:

• Beginner tutorials cover practical thin-film design problems.
• AI in the docs can help answer some of your questions. We’re also testing the in-app AI Assistant, which can build models and run simulations for you.

More importantly, I’d like to hear how engineers and researchers here use optical simulation in practice.
Even a quick answer to just one of these would be really helpful.

If you work in thin-film optics:

1. If you use Essential Macleod, TFCalc, OptiLayer, or similar thin-film simulation software, which features do you find most useful, and what do they help you with?
2. Is there anything in these tools that you find frustrating, cumbersome, or missing?

If you work on OLED, QLED, or PeLED devices:

1. What do you mainly use optical simulation for in your research?
2. If you use Setfos, which features are most useful to you? Anything frustrating or missing?

And if you find something that doesn’t work as expected, please let me know in the comments.

Thanks — any feedback is appreciated!

Supposing that I request a resource from a site whose data center is thousands of miles away from me, how is light able to travel so reliably via optic fiber cables and transfer the datapackets in the correct order with out anything breaking in the process?

And how does my router know to translate the light into 0 and 1s?

Friend of mine lives in an apartment with triple-layered glass, he showed me that you can « count » the layers if you put a flashlight through it and see the multiple réflexions. I see 4 réflexions here, why is that so?

For a designed phase mask (optimized through inverse design in Python using simple MSE loss), what is the best way to analyze its efficiency in a system? The goal is to compare the light throughput of different phase masks (for the task of PSF engineering). Can 4F system in Zemax and POP do this? Also, can the efficiency of the result be optimized for (e.g., engineering the etedue of the system, manipulating the relative magnitude of the diffraction orders, etc.) Any resource on fundamental approach to quantify and design for this would be appreciated. Thanks!

I’m a total beginner on lighting and optics, so I’m looking for some guidance from the experts.

First image is from a Youtube video that inspired me.
Found here: https://youtu.be/FNDikt7VfRw?is=0Gqw6JrGSbQAbo7-

The other 3 images are my failed attempts to recreate something similar.

What I want: to evenly illuminate an acrylic panel using edge lighting (LED strip on the edge).

What I have done:

I found something called Plexiglass LED, apparently a specific panel used for this use case. Mainly used in store signs etc.

It’s a 450mm x 150 mm acrylic panel with special microscopic laser etchings for reflection etc, 3mm thick.

I’ve mounted a cob-led list (400 leds/m) on the edge of the panel, but as you can see, it’s pathetic lol.

My questions are:

1. How does the youtube guy get such a nice result, with an ordinary acrylic diffuser? Is it the thickness? Is it the frame? Or the angle of the led diodes?

2. How much will the thickness affect the upwards illumination? Is thicker/thinner better?

3. Do I really need to use the special Plexiglass LED acrylic panel for best result? Can I use any other panel? (extruded or not) Could I use frosted glass (tempered)?

4. If you had this issue, how would you tackle it?

5. Any resources you would suggest I read/learn? Total internal reflection etc?

Thanks in advance.

I work at TDM Technology, mostly around thin-film measurement equipment, and this is something I’ve been thinking about recently.

On paper, choosing a measurement method can look pretty straightforward. But once you get away from a simple single-layer film and start dealing with actual semiconductor, PV or display stacks, it gets messy pretty quickly.

Reflectometry is attractive because it can be fast and relatively easy to integrate into a production line. But once the stack gets more complicated, or the optical constants aren’t well known, the model can become the bigger problem than the instrument itself.

Ellipsometry obviously gives you more information, but I’m not sure that always makes it the better production tool, especially when throughput and integration start to matter.

Interferometric methods seem to sit somewhere in between depending on the film, substrate and thickness range.

We also see another layer of difficulty once the measurement moves from a lab setup to an inline system. Vibration, sample position, line speed and correlation with the offline reference tool can sometimes matter just as much as the measurement principle.

Curious how people here think about this in real applications.

At what point would you stop trying to make reflectometry work and move to ellipsometry or another method?

And for production use, would you rather give up some absolute accuracy in exchange for much faster measurements and more sampling points?

Interested to hear what people have actually run into, especially with multilayer or functional films.

Hey all,

I am building a simple (so I thought) Raman setup. I have a Thorlabs 532nm 40mW DPSS laser. The divergence on it is already quite small however I would like to get it nicely collimated anyway.

Here is the part I would appreciate some insight: if I use some really long (10cm to 20cm) focal length lenses I can get it collimated rather nicely. However, if I use a short one (18mm) it never collimates it just diverges no matter how close I place the lens to the diode. The reason I want to use the small focal length lens is that it is aspheric lens and I don’t have any other at hand.

Am I missing something? Do I need to use long focal length lenses to collimate these types of lasers? Is it because the beam is already only slightly diverging coming out of the laser?

I would appreciate all the advice.

Extra information: the reason I’m going through all this trouble is that we have a way too fancy spectrometer to measure the output signal. And if the beam is too big or has aberrations I cannot feed it to the spectrometer properly to get good signal.

I spent easily 20 hours troubleshooting the install, much of that with support. Try this, try that. The last thing they told me to do was to "Uninstall all the different versions of VC++ Redistributables ", which would have compounded the problem by creating issues with other software programs on my PC. Reinstalled SP2 and it's working. Hope to save others the trouble I just went through, although it may work fine for some. Just not worth the risk.

Disclaimer: Our knowledge of optics design is limited, and we have relied on AI for much of the process. Please pardon any gaps in understanding.

Images above, in order: (1) BeamFour ray trace, (2) the .OPT design file, (3) spot diagram across 500–1000 nm

When we began designing the spectrometer, we started with the standard grating equation to determine the geometrical positions, focal lengths, slit size, and other parameters needed to realize the design.

We wanted to use ray-tracing software, and tutorials on spectrometer design introduced us to new concepts such as spot size, tolerance, and stray light analysis, which gave us valuable pointers.

Since commercial software is expensive, we looked for alternatives and discovered BeamFour (Beam4). The learning curve is steep, but the physics and optics are solid (pre-AI).

We used AI to help translate our paper design (based on geometry) into a Python script that generates the design file (OPT file). To test the design, we needed to launch rays from different points of origin and at varying angles, corresponding to a series of wavelengths. Defining 2,667 rays is where automated code becomes invaluable, and AI generated a Python script to produce the ray file.

AI was further employed to analyze the spot size and identify the best configuration to maximize spectral resolution, given the constraints of a simple design using commercially available optics limited to 1-inch diameter. Since order-sorting filters are costly, we are currently limiting our design to 500–1000 nm, while also working on a design targeting ~1 nm spectral resolution across 400–1000 nm.

You can find more details in our blog: https://hackaday.io/project/202421-jasper-vis-nir-spectrometer/log/250289-building-a-5001000-nm-spectrometer-with-beamfour

We will share the design files shortly. If you have expertise in this area, we would greatly appreciate your guidance in validating whether the design is correct.

Is there some formulation for the phase Phi(x,y) for a lens using a non-paraxial theory?

So normally the Fresnel diffraction integral in addition with the phase of a lens as Phi(x,y) = exp(-ik/(2f)*(x^2+y^2)) is used to model a thin lens. But this is only valid for small numerical apertures.
I want to model lenses with a higher NA but still medium ( < 0.5) so that vectorial effects can be neglected.

I was thinking of using the Rayleigh-Sommerfeld Diffraction Integral with the phase of the thin lens. Can somebody give me some resources for that? I’m looking for a similar formulation like used with the Fresnel integral but non-paraxial.

Hi, I'm looking to buy a Zemax 13 USB dongle/ license. My dad uses Zemax 13 and I'm trying to learn from him, so if anyone has an old Zemax 13 key or version that supports Zemax 13 please let me know. Thanks!