Hello everyone,
I observed a repeatable interference pattern using a very simple setup, and I’m interested in understanding whether this is just a known thin-film interference effect or if the specific implementation is technically interesting.
Setup:
Green laser pointer
Two ordinary flat glass plates
A thin layer of a custom liquid mixture (3–4 components) between the plates
Projection on a distant screen
Observations:
Without the liquid, the characteristic ring pattern does not appear.
With this specific liquid mixture, a stable concentric ring pattern appears after about one minute and is repeatable.
Changing the laser wavelength (green vs. blue) changes the pattern significantly.
Changing the laser incidence angle can produce different beam profiles (for example, circular, elliptical, or even square-like patterns).
I tested several other liquids, but they did not produce the same stable and repeatable pattern. This specific mixture consistently does.
I have already discussed this with two photonics professors. Both suggested that the underlying physics is most likely classical thin-film interference/Newton’s rings, which I completely accept. I am not claiming a new physical phenomenon.
My question is different:
Could such a simple glass–liquid system be interesting from an optical engineering perspective (for example, passive beam shaping or sensing), assuming the behavior is genuinely repeatable?
I have attached photographs of the experimental setup and the resulting patterns.
I would appreciate your thoughts.

Hey Everyone,

A new Rays and Waves podcast is out!

This time we chat with Xavier from Zygo - a stalwart of the optics industry!

Here, Xavier takes us inside the world of precision optical metrology. We explore how instruments capable of measuring features at astonishing levels of precision support applications across science, industry, aerospace, semiconductor manufacturing, and beyond.

open.spotify.com

Hope you enjoy it 😊

Hihi Maybe this is an EE question but i’m building an optical communications link for my laser and photonics class. And I’m having trouble amplifying the signal that I’m getting from my laser.

I know it’s a circuit issue, but for whatever reason whenever I plug my phone directly into my circuit, my op amp circuit will amplify my phone signal exponentially like 160mv going in 3V going out , however, whenever I plug my laser signal directly into that same circuit, my amp doesn’t amplify enough if that makes sense. Like the power coming out of my photo detector into my circuit is 50 mV, and then the power coming out of my speaker is also 50mV. And I can hear my music it ever so slightly on my speaker and it sounds clear so I know I’m filtering out the DC signal correctly, but I just can’t get the laser signal to amplify the volume with my Op amp circuit even though the same circuit works with my phone how it should. I’ve added an external 9 V battery to give it that extra kick and I’ve tried two amp stages of the exact same circuit, and it double amplifies my phone volume, but I’m still getting the same voltage output as I’m getting the input when I do my laser (50mV in and 50mv out)

I attached a picture of my circuit,
- the red and green wire on the left is my input,
-The red and black wire on the right is my speaker which typically comes out my 470uf capacitor ( it’s not actively plugged in )
- my two resistors are 1K
- I’m using a lm386
-the capacitors from left to right are as follows 1uf 1uf, ceramic 680pf (I think) and 470uf
- the one on the top rail is 47uf and the two on the bottom rail are both 22uf ( I can’t explain the electrical network theory behind why I have them on the rail but whenever I take them off the rail, my signal sounds really messed up so I just keep them up there)

Any help or guidance is greatly appreciated🙏🙏🥹

Hi All,

Presenting my side project to investigate how good LLM can handle lens design.

optivibe-mcp is an experimental MCP server that provides tooling for a coding agent — such as Claude Code — to interface with Zemax OpticStudio.

It exposes OpticStudio operations as typed MCP tools: loading designs, editing lens data, running analyses, optimization, and tolerancing, driven through the ZOS-API so the agent doesn't have to write raw API code. Alongside the tools is a reference layer the agent can query — operand and glass lookups, and full-text search over the OpticStudio manual.

This is early-stage and provided as-is. Expect rough edges.

Hi Folks,

It looks like Telescope-optics.nets domain host has expired. This has been a great free resource for me over the years and would hate to lose it. Does anyone have any ideas or know who managers this site? Thanks.

I noticed that some lenses—especially for mirrorless cameras—have a rearmost element where the radii of curvature for both surfaces are infinite; it is generally around 2mm thick and made of inexpensive glass, such as Schott's N-BK7.

Current Amath undergraduate at University of Washington (my state school). But my parents relocated to Tucson-area. I have an interest in silicon photonics and was wondering which has better prospects.

Some budget phone and special purpose cameras have a fixed focus lens set at hyperfocal distance intended permanent distance vision.

This had led to issues with inability to scan QR. What sort of add-on external element(s) can be used to temporarily enable such cameras to see closer?

https://www.reddit.com/r/Rabbitr1/comments/1dnn5x7/camera_out_of_focus_to_scan_the_activate_qr_code/

Sorry if this sounds dumb, but it's my first time working with an IR laser and my supervisor is out of the country for the week.

We have a Newport IRV1 infrared viewer in the lab and I'm trying to figure out if it still works. I've changed the batteries, but all I get is a uniform gray/beige field and I can't get it to focus.

From what I found online, the IRV1 is discontinued and the photocathode apparently degrades over time. I also came across photos taken through a Find-R-Scope showing a bright green background. So if it were working, shouldn't I see a lit green background through the eyepiece, even out of focus? Has anyone here used the same device who can confirm what a working one looks like?

Thanks!

Architecting the control plane for the MGOC-H120 Photonic Core (GB2616153.9). Pre-silicon. Simulating deterministic AI workloads compiled directly to analog phase shifts.The industry is slamming into a thermal wall with GPU clusters. The bottleneck in SiPh isn't the MZI array; it's the DAC/ADC translation layer and thermal crosstalk.Current architecture constraints and solutions:*

**Power Envelope:** 7.88W total package power. We execute matrix multiplications in the optical domain. Stop burning megawatts to move electrons.* **Control Plane:** Finalizing prototype tape-out with an EU-based mixed-signal ASIC vendor for the high-speed driver array.* **Software Layer:** The Lumis SDK compiles standard PyTorch/ONNX models directly into MZI voltage states. No intermediate CUDA kernels. No vendor lock-in.We are running simulations for UK enterprise clients requiring sovereign, air-gapped compute (zero cloud telemetry).`[Lumis SDK / Compiler Execution Log]````text[SYS] Initializing Adjoint Solver...[SYS] Target: MGOC-H120 (Simulation Mode)[OPT] Mapping weights to phase shifts...[OPT] Converged. Insertion Loss: 0.8dB / stage.[SYS] Deterministic execution verified.```Happy to discuss the math, the thermal mitigation strategies, or the SDK compilation pipeline.Not answering questions on specific unannounced foundry partners.Architecting the control plane for the MGOC-H120 Photonic Core (GB2616153.9). Pre-silicon. Simulating deterministic AI workloads compiled directly to analog phase shifts.

The industry is slamming into a thermal wall with GPU clusters. The bottleneck in SiPh isn't the MZI array; it's the DAC/ADC translation layer and thermal crosstalk.

Current architecture constraints and solutions:

* **Power Envelope:** 7.88W total package power. We execute matrix multiplications in the optical domain. Stop burning megawatts to move electrons.

* **Control Plane:** Finalizing prototype tape-out with an EU-based mixed-signal ASIC vendor for the high-speed driver array.

* **Software Layer:** The Lumis SDK compiles standard PyTorch/ONNX models directly into MZI voltage states. No intermediate CUDA kernels. No vendor lock-in.

We are running simulations for UK enterprise clients requiring sovereign, air-gapped compute (zero cloud telemetry).

`[Lumis SDK / Compiler Execution Log]`

```text

[SYS] Initializing Adjoint Solver...

[SYS] Target: MGOC-H120 (Simulation Mode)

[OPT] Mapping weights to phase shifts...

[OPT] Converged. Insertion Loss: 0.8dB / stage.

[SYS] Deterministic execution verified.

```

Happy to discuss the math, the thermal mitigation strategies, or the SDK compilation pipeline.

Not answering questions on specific unannounced foundry partners.

I’m watching the industry burn 18-month tape-out cycles trying to invent "optical RAM" to build general-purpose optical CPUs. They are translating standard code to SPIR-V, then into custom photonic assembly languages, just to slam into a memory wall because terahertz compute outpaces their read/write speeds.

If you are doing AI inference, you don't need optical RAM. You need deterministic, feed-forward matrix multiplication.

I just open-sourced lumis-nano . It is a dependency-minimal Python script that proves you can compile a PyTorch weight matrix directly into passive optical phase shifts (Mach-Zehnder Interferometers) using pure Singular Value Decomposition (SVD).

- Zero Memory Wall: We compile the weights into static glass before runtime.

- Zero Energy Arithmetic: The optical mesh consumes 0 mW to execute the O(N²) multiply. The math is done by interference during propagation.

- Zero Intermediate ISA: It maps standard matrices directly to physical voltage states.

The script generates the raw ASCII die visualization and calculates the exact milliwatt energy saved vs 45nm digital MAC baselines.

You can run the math yourself: https://github.com/Pr3ndy-ctrl/lumis-nano

Stop trying to make photons act like electrons. Let the physics dictate the architecture.

Draw two circles r = n1 & r = n2.

Draw indicent ray at theta_i. Project the vector component parallel to the interface onto the n2 circle, and flip the sign.

Geometrically you just solved:

n1 Sin theta_i = n2 Sin theta_r

I'm aiming to apply to a company that specializes in optic systems, avionics for pilots, weapons sights etc. I hold a degree in Mechanical Engineering, but have really studied optics apart from the basics that are taught in first year physics courses.

The goal is to self study optics so that I can be a competitive hire for the company. What are some resources and study materials I could use to achieve this?

I'm currently going through "Modern Optical Engineering" and plan on going through "Modern Lens Design".

TIA

Can anyone give me some advice on what type of diamond cutter (maybe a sketch) I should use to apply a diffraction surface to monocrystalline silicon?

I'm working on a personal project: a moving-head fixture where I want the narrowest beam angle possible, but with a moving lens/optic setup so it can also open up and function as a wash. Basically a spot-to-wash zoom mechanism, not a fixed narrow-beam optic.

if been looking for a part like this: https://lightspares.com/glp-impression-x4-lightpipe-primary-optic-assy-069-054

I don't need an exact OEM part — I'm looking for either:

1. A generic/catalog light pipe or collimator I can adapt into the design, or
2. A supplier/manufacturer who can produce a custom one (injection-molded PMMA/PC, or low-volume 3D printed/CNC'd for prototyping)

One option I've already found that looks promising is the LEDiL Gabriella 45 G2 (L20260_GABRIELLA-45-G2-RS-PIN) — a ~6° spot lens, 45mm diameter, 27.2mm height, pin-mount, clear PMMA. That narrow a beam angle is close to what I want as a starting point.

https://www.ledil.com/product-card/?product=L20260_GABRIELLA-45-G2-RS-PIN

Specs:

• LED source: Cree XLamp XN-P
• Target spot beam angle: as narrow as possible (single digit degrees)
• Wash/flood requirement: needs to open up via a moving secondary lens away from the primary optic, not just a fixed optic
• Secondary moving lens: leaning toward a plano-convex lens — open to other suggestions if there's a better type for this
• Material preference: PMMA, polycarbonate, glass, no preference
• Quantity: 1 prototype / small batch / production run

hey y’all, looking for some advice. apologies if this isn’t the right space.
graduated in ‘25 in astrophysics, doing a masters in optics now because I realized I wanted more hands-on engineering stuff and possibly go into astronomical engineering. haven’t had any luck getting a better job and wanted to see if anyone had any insight or ways for me to gain experience so I can put myself in a good spot come graduation from my MS.
any this point, I’m really open to anything as long as it’s challenging, it’s R&D, and hopefully in some science sector.
I’ve attached my resume for context.

I’ve been working with 800G OSFP modules (DR8/FR8) in AI cluster builds, and the thermal behavior is honestly more extreme than many people expect. Sharing some notes here to see if others have seen similar patterns.

1. Power consumption is no joke
Most 800G OSFP modules sit around 16–21W, and some FR8/long‑reach variants push 22–24W. That’s basically a small CPU inside the switch port.

2. OSFP cages run hotter than QSFP‑DD
The larger form factor helps with signal integrity, but the thermal density is still high. In a fully populated chassis, OSFP cages often run 10–15°C hotter than the ambient airflow.

3. Airflow direction matters more than people think
Side‑to‑side airflow switches (some AI fabrics use them) can cause uneven cooling. We’ve seen cases where the “hot side” OSFP ports hit 70–75°C, while the opposite side stays under 60°C.

4. DR8 vs FR8 thermal difference
DR8 tends to be slightly cooler (lower DSP load), while FR8 modules consistently run hotter due to stronger DSP equalization + longer‑reach laser drive. The difference is usually 2–4°C.

5. Fully populated OSFP line cards are a thermal event
Once you fill all OSFP ports with 800G modules, the switch fans ramp aggressively. Some vendors even warn that full OSFP population may reduce component lifetime if airflow is insufficient.

TL;DR:
800G OSFP modules routinely run 20W+, cages get hot fast, FR8 runs hotter than DR8, and full OSFP line cards can push switch cooling to the limit.

Curious what temps others are seeing in production. Anyone hitting 75°C+ under load?

I noticed this while almost closing my front door. This is not from car headlights. There is a window with evenly spaced bars/slats directly in front of the door.

When the door is almost closed, this sharp striped pattern appears on the floor. The lines are evenly spaced and surprisingly crisp. Opening the door wider makes the effect change or disappear.

Is this a camera obscura/pinhole projection of the window through the narrow gap between the door and the frame, or is another optical effect responsible? Why are the stripes so uniform?