| ▲ | dekhn a day ago |
| With products from a vendor like Thor Labs, you're getting a lot of quality and knowledge built into the system. Mechanical engineers, electrical engineers, optical engineers... all of which means an edu kit like that will train a student to be useful in most grad research labs (which often build their systems out of thor labs components). It sort of depends on what your goal is; personally, I live to see something expensive on Thorlabs, and make a simplified, less accurate, and far cheaper alternative in my home lab. But that's rarely how folks in labs do it- instead, they will focus on getting people to be useful for performing state of the art research, which usually depends on applying hundreds of years of experience to make some tiny marginal improvement, which frequently depends on having extremely precise and accurate gear. |
|
| ▲ | LolWolf a day ago | parent | next [-] |
| Hopefully you enjoyed the post then! I think there's just such a huge middle ground that's missing (for funny historical reasons[1]) between "children's toy" and "lab-grade equipment" especially in optics, which is why I was excited to make this my first foray into making a fully 3d printed "useful-ish" thing that doesn't really exist otherwise. --- [1] This is because most lab equipment was made _in the lab_ back in the 60s or so, and having this technical ability was a huge advantage for many labs. Now, personnel cost/hours are much more expensive relative to equipment, so people will pretty much pay whatever to get lab-grade stuff. |
| |
| ▲ | dekhn a day ago | parent [-] | | I haven't read the post yet because my work blocks access to the domain. I agree there is a huge middle ground- for example, I make hobby microscopes at home, and much of my work has been making accurate and precise 2D/3D stages. It's easy to buy great, simple (non-motorized) scopes with good optical quality, but as soon as you start adding motorized stages, or any sort of complicated illumination or filtering, it gets challenging quickly. My actual goal is to track microbes in real time using computer vision, but the professional hardware to do so is out of my price range. I have spent literally thousands of hours fiddling with one part or another Today, I'm working on a high speed flash illuminator that is coupled to the camera, and it's one problem after another. Reality has a fractal level of detail. Since I haven't been able to look at your project yet, I don't know if you worked on this area, but I found it really useful to clone the Thorlabs cage system components: https://www.thorlabs.com/optical-cage-systems and specifically https://www.thorlabs.com/item/CXY2A (you can download their 3D model and see that the mechanism isn't that complex). Another thing I've ended up doing is prototyping in plastic and then having it machined at a place like JLCPCB out of aluminum. PLA is just flexible enough (especially under load) that it can make the results very frustrating. | | |
| ▲ | LolWolf a day ago | parent [-] | | ah I see! Yes this is very cool (hope you make it open source :) but have you taken a peek at the openflexure project? They make a fully motorized 3-axis microscope that is 3d printed and relatively inexpensive (parts+motors+electronics - PLA net out to USD 250?) it’s very cool! maybe you can also take some ideas from there :) https://openflexure.org/ | | |
| ▲ | dekhn a day ago | parent [-] | | I don't particularly like the openflexure approach. Instead, I build stages similar to standard XY stages: https://www.asiimaging.com/products/stages/xy-inverted-stage... which uses standard motion components (linear rail and linear bearings, 3d printer style steppers), all of which gets mounted on aluminum extrusion (4040). Then the illuminator and camera just get mounted on the aluminum extrusion. It's pretty close to the Thorlabs Cerna, https://www.thorlabs.com/cerna-r-series-modular-microscopy-s... although I just do low-magnification light microscopy. | | |
| ▲ | LolWolf a day ago | parent [-] | | I see, what’s the min step size you’re going for? | | |
| ▲ | dekhn a day ago | parent [-] | | typically around one micron (which is about the same as one pixel with my objective and camera). I am not trying to take min steps. I'd rather have smooth motion, with fairly high accuracy. The current system I am building is mainly optimized around scanning large areas quickly; I have already demonstrated that I can create accurate stitches by moving, stopping, taking photo, repeat, but it's slow (due to the stopping) so I am working on an approach that keeps the stage moving constantly, but triggers a bright flash that freezes intermediate exposures. This gives a good 10X speedup over the simpler model of move/stop/photo/repeat but brings in a number of other challenges. | | |
| ▲ | LolWolf a day ago | parent [-] | | ah very cool, I see! good luck! are you posting updates anywhere? |
|
|
|
|
|
|
|
| ▲ | zipy124 a day ago | parent | prev | next [-] |
| As a student at a top worldwide university, I can tell you we order a lot more stuff off Amazon and eBay than you'd think. There's an awkward middle ground where you either buy something cheap or make it yourself because labour is basically free in academia thanks to the large amount of students and staff but grant money is not. |
| |
| ▲ | dekhn a day ago | parent | next [-] | | But what do you down with the Thorlabs Lab Snacks? I thought that was the main reason grad students ordered things from them. | |
| ▲ | LolWolf a day ago | parent | prev [-] | | yes ! but it also assumes you have: a good optical breadboard + bench + dampeners, a beautiful set of lenses, all sorts of nice lasers and kinematic mounts and linear stages etc etc so yes, we _also_ (back in my phd lab) built equipment in that sense, but there was a pretty good foundation of Fairly Fancy stuff already sitting around ! | | |
| ▲ | zipy124 15 hours ago | parent [-] | | All of those parts can also be acquired through alibaba for a stiff discount off the thorlabs pieces though. Whilst some labs have fancy stuff going around, a significant amount don't and there isn't very good equipment sharing between labs at most institutions. | | |
|
|
|
| ▲ | CamperBob2 a day ago | parent | prev [-] |
| In some cases, you'll learn more from crappy hardware than you will from lab-grade gear. This is probably one of those cases. This build will require thoughtful attention and debugging/optimization on the student's part in ways that the Thor Labs kit might not. I mean, it's practically the most basic optical experiment that you can perform. Nobody needs to pay $3K to learn how an interferometer works. It's not a MoT or something exotic like that, it's a beam splitter and a couple of mirrors. Put another way, it's the difference between building a Heathkit and putting a bunch of parts together that you salvaged from other stuff, for those who are old enough to grasp that analogy. |
| |
