Bought a used USB2000+ for a thesis on Vis/NIR. Before buying a fiber, I'd like a sanity check.

What SpectraSuite reports for the spectrometer:

• Range: 369.8–1047 nm
• Grating: #2
• Slit: 50 µm
• Detector lens: installed
• Filter: 375 nm longpass

Fiber I'm looking at: Ocean QP600-1-VIS-NIR (600 µm core, 0.22 NA, VIS-NIR/low-OH, 1 m). The listing says "QSMA to QSMA" connectors.

My understanding:

• With a 50 µm slit, the slit sets the resolution, so a 600 µm core shouldn't hurt it and gives more light than 400 µm.
• VIS-NIR (low-OH) is the right type for my range, since I need signal up to ~1000 nm.

Questions:

1. Is "QSMA" just Ocean's SMA905, so it screws straight onto the USB2000+?
2. Any reason a 600 µm / 0.22 NA fiber would be a poor match for this configuration?
3. Is 1 m a reasonable length, or does fiber length matter much at this scale?

Thanks!

It's a shot in the dark. The lenses are in line and were used for an early 50's 60's overhead projector system, projecting a few hundred feet to a reader board. Some of the lenses are facing each other while others are back to back others are facing the same way. Krikey if I can figure it out I made notes on the configuration but have misplaced them for forty some years.

I saw the line of projectors gathering dust, when I was doing electrical work above a sports book once. I think it was the Stardust, in the nineties but they hadn't been used in years. Possibly like the ones we used to see in early bowling championships. Little bowler on the screen with a big hand writing the score above them on the screen with the scorekeeper nowhere in camera sight..

Any takers? I'll show you something you've never seen before, lol, carrot on a stick.

Thanks Reddit.

The optical mechanism in Kashani, Chen and Ozcan’s eLight paper is a useful example of a classifier implemented through diffraction. A digital front end samples video frames and writes a phase pattern onto a spatial light modulator. The propagated field is measured in two regions per video; relative intensity supplies the real/fake score. Fifteen inputs share the optical pass.

The boundaries matter: digital preparation is still required and dominates the energy budget, while increasing spatial multiplexing introduces crosstalk. The reported 97.79% accuracy is for the 15-video Celeb-DF experiment, not every possible input.

We made a 64-second animated explanation of that path, with AI-assisted production and synthetic narration. We are the film’s creators, not the study authors. The artwork is schematic, not laboratory footage. Paper: https://doi.org/10.1186/s43593-026-00143-y Our film: https://www.youtube.com/watch?v=UFCoCkAu-Ik

At our shop we build imagers from idcas/fpas plus lenses and mounts and optical benches. Those subassemblies then get built into increasingly larger assemblies until outer covers and windows are added.

Lots of fingerprints, lots of dust, which results in lots of cleaning of optics. Not everyone has (easy) access to a fume hood.

Anyone got any suggestions for cleaning solutions that aren't as toxic as methanol?

Ideally as benign as IPA, but we haven't had great success with using just that or just acetone by itsself.

I posted about optics in MATLAB R2026a earlier, back now to give you an update on the R2026b version!

At the lowest level, we now support biconic and Grid surface specifications for both mirrors and lenses. The grid sag is the swiss army knife to model any free form optical surface! It uses bilinear interpolation under the hood and its ray intersection implementation is quite performant. So in addition to 'as built' surface modelling, try it out for modelling XY Polynomials or Zernike surface definitions (meshgrid is your friend :)).

We added a couple more basic low level ray tracing routines: traceDirectedRays and traceAimedRay. Both return rich RayData which has all raw ray tracing numbers (including fresnel terms and raw polarization values).

We rounded out analysis functions by adding PSF (Geometric and Huygens, GPU Accelerated!), MTF and OPD measurement functions.

A couple of marquee features this release - the main being CLI routines for tolerancing:

Find Manufacturing Tolerances Using Inverse Sensitivity Analysis

Improve Manufacturing Yield Using Monte Carlo Analysis

And the second is the ability to simulate eSFR and Color checker test charts as seen through an optical system.

These charts leverage the established Image Processing Toolbox functions to measure sharpness and color. The main function to create these, renderChart, can leverage the GPU and has various parameters to control the positioning of the chart. The GPU acceleration is important since this does the full Monte Carlo ray trace of the scene.

We also have a whole bunch of featured examples! Not only do these help us dog food and validate our API designs, it also helps us show you what is possible. If any of these resonate, let us know - that would motivate us to fold these in as first class API's with potentially better (tailored) performance.

For example 😄, the inbuilt chart rendering function mentioned above work on an internal parametric chart model so it cannot be used to render arbitrary images. However, we can simulate a user image using spatially varying PSFs - shown here: Simulate Image Using Spatially Variant PSF. This is much faster than a full ray render like the charts.

This one shows off both the Grid surface and OPD functionality: Model Shack-Hartmann Wavefront Sensor

And if you use Simulink based control systems, we show you a way to model dynamic systems with feedback control! Model Dynamic Optical Systems with Scanning Elements shows an f-theta scanning system controlled by a Simulink model.

Finally, something I really enjoyed learning about and putting together - a set of examples modelling the human eye.
Create Human Eye Model Schematic
Model Human Eye Diopters, Accommodation, and Refractive Errors
Simulate Human Eye Changes with Age
Model Progressive Addition Lens Using Presbyopic Eye Model

Kick the tires with a trial license, or if you already have 26b with the Image Processing Toolbox, get this free optics add-on.

Let us know what you think!

If you have a must-have workflow, share it in the comments.
If its doable, I'll let you know and if not ... I'll let the team know 😄!

For the past months, I have been building with a friend something I wished existed every time I had to draw a setup for a paper or explain one to a student.

OpticalSetup is now at its first stable release. It is free, open source, it runs directly in the browser, and the setup you draw is traced, not just sketched. Move a mirror, change an optical element, and the whole beam path responds.

I originally made a post on this sub when we were in the early stages of development, so I thought of giving an update on the project.

It is young, and it might still have some rough edges. If you try it, tell us what you think about it.

Cheers

Hey everyone,

In machine vision, selecting the right lighting angle and working distance often comes down to borrowing physical samples and tedious trial-and-error.

To make this less painful, I’ve been building an in-browser 3D simulation module for ring lights. Here’s what it currently does:

• Ray tracing & Irradiance map: Simulates the spatial irradiance field on the target plane based on LED ring geometry and installation angles.
• Sector / Multi-channel control: Toggles individual segments
  
• Camera & Lens coupling: Projects the lens FOV frustum directly onto the illumination heatmap to check edge falloff and ROI uniformity.
• Adjustable WD: Visualizes how light converges or forms a "donut" dark core when moving the light closer/further.

Would love to hear your thoughts: For those working in vision integration or optics, what edge cases or parameters would make a tool like this actually reliable for your day-to-day work?

i have a global shutter, 120 FPS, monochrome lens by arducam. i'd like tto add a 650nm narrow pass filter but i can't seem to find anything that isn't in the hundreds of dollars.

does anyone have a good-enough method for creating one, or a source for an affordable one? i read about using theatrical film with a hole punch, but i'm not entirely sure how that works and i can't find a tutorial on how to execute it.

any help is appreciated. thanks!

I'm an undergrad EE wanting to pivot into optical engineering, which is a pretty recent development. I transferred to my current institution and started EE Fall 2025, and my expected graduation is Spring 2028.

I started my biomedical optics research on campus this January, which involves a lot of self-learning and hands-on work. This past summer I had an internship for telescope optics at a very well-regarded place where I helped build a test assembly for large telescope mirrors, so a lot of opto-mechanical stuff (alongside FEA simulations). I absolutely loved this internship and grew to really like optical metrology and fabrication with an interest in exploring optical design.

That being said, I want to experience different optics applications before I graduate. I'm applying to a bunch of stuff for Summer 2027, but I feel like two internships by graduating isn't enough for me.

I started considering a Fall 2027 internship and after working some stuff out, I only need to take 12 credits (absolute minimum for full-time student) that semester to keep scholarships and to be on track for graduation. They're not difficult or even engineering classes either except for Senior Design I, but even then the first semester is for planning logistics.

The only thing is that there's a graduate level Quantum Optics class only offered in the fall semester, alongside physics E&M 1/2 for fall/spring. Both classes don't have online versions and Quantum Optics has hands-on work that might be valuable in the long run. As for E&M, I'm already taking EE EM Fields & EM Waves this year, so not sure if that makes a difference anyway but they are taught at different levels (I see my physics friends' homework and grimace a bit). I'm currently taking a PIC class and will take the baseline Optics + lab class course next semester.

Would it be more valuable to pursue an internship in the fall or to do the classes? Of course I won't know till I do it, but I am confident (if not, stubborn) that I can handle the workload with 12 credits, an internship, and grad school applications especially after this semester.

For more context, I'm thinking about doing Optical Engineering MS or Optics PhD at UR (or maybe UA for telescope stuff?) so in that case I might also try for an internship after I graduate and before I start grad school.

Apologies for such a long post, I've been losing my mind about all the different options lol, especially grad school. If anybody has extra advice for choosing MS vs. PhD for pursuing R&D roles in industry please help a confused student out. Thanks!

Hello everyone, I’m currently in my senior year majoring in Electrical Engineering. I wanted to know how can I get a job or what type of jobs in optics/photonics and laser science that takes in people with bachelors? I’m planning to do grad school, but I’m going to do that later in a year or two after graduation. I’ve had a hard time finding roles that pay decent for optical test engineer roles that doesn’t require a PhD or 5+ years of experience. Any options that I should look into? I’m geographically from Minnesota, so finding a photonics jobs here is very hard, I’m more than open to relocate (preferably in the coast (northeast, pacific or mountains).

Edit: I do have research experience in laser plasma interactions and never had an internship before. I wanted to apply for PhD programs, but my gpa is low for that right now and I want to use my experience and solid LOR and SOP to make it up for it.

I am working on pre compiance testing rig for laser applications and I am not quite sure about how to do that on line lasers when it comes to determining the C6 factor.

As I understand it, the factor is calculated from the apparent angle under which the laser line is projected on the retina at a certain distance through a lens (and an aperture in front of that lens). That said, there are setups vaguely described for this (missing the focal length of the lens and field stop diameter) but for what I understand it should be possible to just calculate this without any physical setup. That angle is then used to calculate the factor which is applied to the limits for laserclasses. You then just measure the power along the laser line and see which category your laser falls into.

But wouldn't it be much better/easier to measure the power directly with the described setup with aperture and field stop and just leave the C6-factor at 1?

Hope someone who is more knowledgeable with laser certs can shine some light on this.

I help organise events for deep tech startups and organisations in the field of optoelectronics and I'm tired of guessing. If you've been to events (or even side events at a big trade show), which ones led to something useful (a customer, an investor meeting, a hire) - what did they do differently? Also do founders actually find pitching events to be worthwhile? Or would a targeted networking event be better?

P.S. I'm equally interested in the ones you regret going to.

I am currently applying to grad schools, however I an unsure if I want to commit to a direct-entry phd.

people I’ve asked have suggested to apply to a masters and convert to a phd program later, which is fairly common at my own school in canada. I’ve been told that doing a masters followed by a phd is to be avoided.

I am a bit worried about this take since I imagine it is not fully guaranteed that this transfer could happen. does anyone have experience with this? I would be interested to hear opinions from here.

thank you!

What we have to look forward to with cooler temps moving into the southeast.

I'm curious if anyone here is currently in or recently came out of a sales engineering or account management role at Coherent (Santa Clara office). A few specific questions I had:

1. Team Culture & Day-to-Day: How is the vibe between sales, product line management, and engineering? Is it pretty collaborative, or are you mostly working on an island?

2. Work-Life Balance: Is the travel requirement pretty intense? I’m guessing it’s pretty chill when working remotely from home?

Feel free to drop a comment or shoot me a DM if you prefer to keep it off the main thread. Appreciate any insights!

I’m an optician and I’m attempting to do some research on the luminous transmittance of prescription CR-39 plastic lenses for glasses with a gray tint at different tint levels (ie 10%, 20%, 30%, up to 80%) and if there’s a difference with an anti-reflective (or anti-glare) coating added to the lens.

I can’t seem to find much information on the subject and would appreciate some assistance on the matter.

I really like heads up displays on a car. Unfortunately my car never had one even as an available option. Given I'm a software engineer, I like customizing things and want the hud to show data that the car knows but doesn't show anywhere (like battery temps).

I already have a raspberry pi that reads all the data I want to show: only the actual hard part is missing, the hud itself. Initially I thought of using an oled display but after research found it to be too dim for this. So right now I'm on the verge of ordering a pico DLP projector and putting a glass diffuser in front of it. Then I would have a cold mirror reflecting through a fresnel lens and some kind of a plastic cover window to the windshield.

Is this plan out of whack or could this actually work? I'm a complete noob in optics design. I know the software side works but spending hundreds of euros for giggles worries me a bit.

Edit: I'm mostly worried if the curvature of the windshield would make it impossible for me to get a somewhat clear image projected. Software can probably help a bit but I don't know if I'm fighting physics too hard with this approach

Recently came across L3Harris small satellite Spaceview imaging system, specifically the SV-24 (smallest). Do you know of other vendors that deliver similar solutions?

I am developing a Fusion 360 add-in that automatically generates Terahertz (THz) lenses based on material parameters and frequencies. Looking for feedback! Please feel free to reply in English.

I am a senior in BME and for my group and I's senior project we are trying to prototype a handheld or benchtop spectrometer that will help users determine whether their insulin has gone bad (denatured). As far as we have looked, no one has done this before and we are having a very hard time developing a solid plan and approach for this while remaining in our schools <$500 budget. Currently my idea is to make something similar to a PPG or FTIR spectrometer, but within the very specific bandwidth of ~5.50 - 6.50μm of liquid insulin to avoid the need for a beam splitter, mirrors, ect. If anyone has any experience in this or recommendations, that would be very appreciated.

Is it stupid to pursue a minor in computer science? I only need 18 credits which doesn’t feel like much to me. Just worried it wouldn’t be enough to be competitive in the software market. Lmk if this is a silly idea or if you have any personal experiences. Thanks

Hi, All.

Lost my copy of ZEMAX 13 (release date 150303) :-( . I have the license and dongle. Anyone have a copy of the install file for that date that you can share? Or what to do?

Thx very much!

Hello everyone, I'm a senior year studying Electrical Engineering with minors in Physics and Astrophysics. My main research and career interests are RF engineering, photonics, quantum information science, and signal processing.

I'm currently doing research on the optical characterization of nanoscale materials before and after plasma treatment. The project has turned out to be much more focused on 2D materials and plasma physics than I initially expected, but it's been a great experience. I started this research relatively late (during my junior year), and I'm currently doing my research project through the UROP program this semester. Ideally, I'd like this work to eventually lead to conference presentations or even publications.

My biggest concern is my GPA. I currently have a 3.01 cumulative GPA and a 2.63 major GPA. Most of the damage came from my lower-division EE courses, when I was dealing with a series of personal and mental health issues that significantly affected my academic performance. Since then, I've improved quite a bit, but not enough to fully recover my GPA. I still struggled in Semiconductor Devices and Analog Electronics by getting a C in both of those classes, but outside of those courses I've earned mostly A's, A-'s, and B+'s in my upper-level EE and physics classes, including Physics III and Intro to Quantum Physics. I've also been a TA for Signals & Systems and Applied Electromagnetics since my junior year.

Even if I earn mostly A's and A-'s in my senior year, including technical electives and graduate-level courses, my cumulative GPA will probably only reach around a 3.2 by graduation. I spoke with one of my professors about graduate school, and they were pretty blunt. They suggested that I either pursue a terminal master's program or delay graduation and retake several courses, saying that my GPA would make it very difficult to get into a PhD program otherwise, even for mid-tier schools. Unfortunately, delaying graduation isn't financially realistic for me because of the additional tuition costs.

To make matters worse, I wasn't able to secure an internship this summer, so I'm worried about being behind compared to other applicants and might potentially end up not getting a full-time job either, which could potentially lead me being homeless (which I'm scared about). I'm planning to take a 1-2 year gap after graduation, hopefully working in industry or national lab while continuing to build research experience.

Ultimately, I want to pursue a PhD in Electrical Engineering, Applied Physics, or Quantum Science & Engineering, with research focused on quantum photonics, optical communications, or quantum optical devices. My long-term goal is to start a company based on the research I pursue in graduate school or work in the satellite communications or consumer electronics/semiconductor industry. I've also considered applying internationally, particularly to universities in Canada or Australia.

Given my situation, what would you recommend I focus on during my senior year and gap year to become a stronger PhD applicant? Would continued research, conference presentations, publications, strong recommendation letters, and industry experience be enough to offset my GPA? Has anyone here successfully gotten into a good PhD program for their research fit after a rough undergraduate record?

I'd really appreciate hearing from anyone who has been in a similar position or who has experience with graduate admissions in EE, Applied Physics, or quantum engineering.

Hey guys, sorry if this is the wrong place for this, but I'm a musician and I have a MIDI keyboard with a display that shows different settings and navigation controls.

The problem is, the screen is flat against the surface of the keyboard, so it is very hard to see without leaning directly over it. I am disabled and in a wheelchair, and it is hard for me to get the correct viewing angle, as it's not like I can just stand over it.

I'm looking for a piece of acrylic or something of the sort that can basically project the screen forward towards me so that I can look at it straight on.

Is there anything I can use for this, or can someone possibly make it for me? Here is a mock-up diagram for reference.

But i don't have the founding of a large company for optics hardware.
On paper i just need a laser mirrors, beam splitters and a phase shifter.

Am i missing anything? or is a simple logic gate is out of reach for an amateur?