Awesome article, wild equation
Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
11–20 of 219 posts
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#12The paper is from Nov 2018, and is easy to find online. It’s a pretty amazing result; the examples they give in the paper are for some reasonable shaped primary surfaces and some really neat “exotic” stuff. The solution actually admits aberrant free solutions for any geometry that doesn’t include self-crossing rays. So, some of the ‘weird’ examples include a Bessel-function cross section, negative index of refraction, and lenses that focus at negative infinity.
The author’s have a paper from March 2019 (in arXiv) that uses the result to build some novel telescope geometries.
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#13Awesome article, wild equation
Don't such things always seem a bit obvious in retrospect?
/joke
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#14> In this equation we describe how the shape of the second aspherical surface of the given lens should be given a first surface, which is provided by the user, as well as the object-image distance [...] (emphasis mine) I didn't check out the paper in detail, sounds like the shape of the correction surface depends on the distance to what you're imaging? Does it do so in a non-trivial way? If so, this sounds a bit more…
So it's useful if distance to your object changes predictably enough, like in astronomy, satellite imaging and many other kinds of space missions.
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#15> In this equation we describe how the shape of the second aspherical surface of the given lens should be given a first surface, which is provided by the user, as well as the object-image distance [...] (emphasis mine) I didn't check out the paper in detail, sounds like the shape of the correction surface depends on the distance to what you're imaging? Does it do so in a non-trivial way? If so, this sounds a bit more…
So it's useful if distance to your object changes predictably enough, like in astronomy, satellite imaging and many other kinds of space missions.
Well in astronomy you usually want your telescope to be able to observe different targets. So it depends on the details of how the correction surface has to change when the image-object distance.
If it's just a mild deformation and offset, then yeah I guess technology similar to adaptive mirrors could work well.
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#16> In this equation we describe how the shape of the second aspherical surface of the given lens should be given a first surface, which is provided by the user, as well as the object-image distance [...] (emphasis mine) I didn't check out the paper in detail, sounds like the shape of the correction surface depends on the distance to what you're imaging? Does it do so in a non-trivial way? If so, this sounds a bit more…
I used to be a photographer and have stared at the lens group diagrams from many a lens manufacturer, so take this with a grain of salt: In a lens there are multiple lens groups, it's often that the aberration correction is its own distinct group, with fixed input and output groups flanking it. I'd imagine that the distance to the projection surface, in this case the next lens group, can be fixed and thus distinct from the distance to your ultimate subject. A fun fact is that Helmholtz reciprocity says that regardless which direction light passes through an optical system you can reverse the distortion and reconstruct the input signal.
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#17I'm not sure I really follow how this actually will result in better lenses. Is the precision of the numerical solution really the problem, or is the problem the actual precise manufacturing of the lens elements?
I have a strong suspicion that the numerical solution is as precise as needed and the limiting factor is the manufacturing, but I would be interested to hear how this results in something new.
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#18Will this have any implications for astronomy?
From another comment in this thread:
"The author’s have a paper from March 2019 (in arXiv) that uses the result to build some novel telescope geometries."
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#19I have not checked the actual paper, but according to the article itself:
> Moreover, the solution involved aspherical elements, which are harder to manufacture in a precise way and are thus more costly.
> Their findings were published in the article General Formula for Bi-Aspheric Singlet Lens Design Free of Spherical Aberration, in the journal Applied Optics.
I’m no expert in optics, but that does not sound like the kind of advancement that cheapens lenses, even if the math work is mathematically relevant
Re: Goodbye Aberration: Physicist Solves 2,000-Year-Old Optical Problem
#20Hopefully this will increase the sweet spot in the VR headsets.
VR headset lens already require software chromatic abberration correction -- I'm curious what constraints if any would limit the application of this new result for VR spherical aberrations. Would love some thoughts from an optics expert on this. I also wonder if this new knowledge could contribute to a software corrector.