#559

Рет қаралды 7,804

Күн бұрын

Пікірлер: 32

@stanpruitt 2 жыл бұрын

When my stage lighting carrer got put one hold I decided to dedicate a good amount of time and old fixtures to learn what every component on each PCB did. So I could come out the other side of COVID replacing a $0.10 whatever rather than the usual practice of ordering new PCBs. Well.. this also led me down the path of building my own fixtures (personal use only). Long story short; I am self-taught and after playing around with some TIR lenses I intuitively felt something was going on as I tried increasing output via reflectors and taking amateur measurements. I think I just got my answer. Evanescent Waves = magic basically. THANK YOU!

@IMSAIGuy 2 жыл бұрын

Great that you found something productive and fulfilling to do during Covid. This channel has helped me.

@budgetlightph7814 2 жыл бұрын

I wonder how they will compare to regular reflectors in terms of beam intensity. I'm currently trying to replace my flashlight reflector with a TIR hoping that it would offer more impact resistance. I'm not so confident with the thin glass lens of my reflector. I ordered the smallest available 5⁰ TIR to maximize beam intensity. I hope it doesn't drop too much throw since I needed the range. If it does then it's back to reflector I guess. I already tried wider angles and I loved how well they perform on close up. Just not sure how well the 5⁰ lens would throw. 🙂🙂🙂

@ebrombaugh 4 жыл бұрын

I remember when I was taking a course in fiber optics and learned about evanescent coupling. It seemed like magic.

@IMSAIGuy 4 жыл бұрын

it IS magic. It works in electricity too. All the same stuff. the first time I learned it was in E&M physics class studying waveguides. I had a need to do some calculations once in optics and got out my old physics book to get the equations.

@andrewnorris5415 5 ай бұрын

Nice! Is it true that TIR produces a wider flood but less bright? And TIR can go futher with focused spot. I have an interesting dynamo cycle light from Phillips. The bulb faced backwards and shines onto a reflector I think (or PIR?). It allows them to shape the light beam precisely, so just a bit goes up and it lights up the road evenly with a bit to the side for cornering! I have no idea what that design is called but it works well for road cycling, making the most of the lumens!

@IMSAIGuy 5 ай бұрын

the design of the lens can be made to be wide or narrow. similar to designs of CPC: kzbin.info/www/bejne/oJDahahjqr-bnqssi=6W9sQxZIPBWLfKsf

@andrewnorris5415 5 ай бұрын

@@IMSAIGuy Thanks!

@SimoWill75 4 жыл бұрын

I'd like to try some TIR's with my DIY bike lights with XHP70.2's but they're hard to get for the 7x7 die. Atleast they were when I made the light. Using Fraen reflectors instead, the light spill actually turned into an advantage in my case, works as a flood/spot in one.

@borisn879 Жыл бұрын

Thanks for the great lecture.

@logeen Жыл бұрын

great video - thank you I'm from Poland and I'm wondering how to modify the lenses (probably TIR) in the headlights, e.g. Ford Fusion full LED 2018, so that the low beam glows asymmetrically (EU regulations). It seems to me that the grooved plane visible in their lens would need to be modified. You have an idea?

@IMSAIGuy Жыл бұрын

headlight optics are very complicated. almost impossible to modify

@logeen_makerspace Жыл бұрын

Almost ;)

@PapasDino 4 жыл бұрын

Always learn something new watching your videos! I know ads support the YT channels but the mid-roll ads are really starting to get annoying, sigh...

@cryora 10 ай бұрын

Is it possible to produce a collimated beam from an LED that diverges very little over a long distance (similar to a laser)? If the LED is a point source, then one can place it at the focal point of the lens, however, physical LEDs are not point sources, so when placed in the focal plane, it will always produce a diverging beam. The light sources off-axis get focused to infinity but at an angle relative to the axis.

@IMSAIGuy 10 ай бұрын

I think you answered your own question. If you want to do the math, look up Entendue: en.wikipedia.org/wiki/Etendue

@cryora 10 ай бұрын

@@IMSAIGuy Ok so etendue never decreases if power is conserved. I was able to reduce the spread by using an aperture, but that of course reduces power. I was hoping there was an intermediate solution where you can keep more of the power while collimating the beam to any desired angle. Putting a pupil behind a focusing lens reduces the overall amount of light, or at most creates a vignette, rather than block out the large angle lights. I've thought of using 2 pupils or putting the pupil far away but that adds more complexity and size to the design.

@IMSAIGuy 10 ай бұрын

area * solid angle is constant AKA 2nd law of thermodynamics or I learned it in Physics as the Lagrange Invariant. @@cryora

@johnjohn-ed9qt 4 жыл бұрын

Interesting. Thanks you for the explanation.

@koningklootzak7788 9 ай бұрын

I received bunch of TIR lenses in different degrees. How can i tell which is shallow and which is deep?

@IMSAIGuy 9 ай бұрын

not sure what you mean by shallow and deep, but in general, these lenses are made for individual uses. you would need the datasheet for each lens. of course you can just try them and see if any work for your application

@koningklootzak7788 9 ай бұрын

@@IMSAIGuy how can I tell which lens is wider than the other? It's very hard to tell.

@IMSAIGuy 9 ай бұрын

@@koningklootzak7788 again, you don't know what type/shape of LED these lenses were designed for. you can just put some random LED under the lens and see how it reacts. just shine it on the wall. if you want to be scientific. you use a calibrated camera and use software to measure the intensity at each point.

@koningklootzak7788 9 ай бұрын

@@IMSAIGuy I do know. These are 3535 lenses. I've figured out now. Thanks.