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Making My Own Glasses

eidel.io

61–70 of 189 posts

Re: Making My Own Glasses

#61
I were assembling a home-optometry kit, I would use adjustable oil lenses and a laser pointer. The speckle pattern of the laser dot is affected by whether the observer is myopic or hyperopic. Adjust the oil glasses until, when moving your head, the laser speckle dots do not appear to move. If they move opposite to your head motion, make the lens diopter more negative, and if they move in the same direction, make the lens diopter less negative.

After determining exact spherical diopter, then test for astigmatism by spinning a set of parallel black lines on a white field, and parallel white lines on a black field. Or just look at a printout of an astigmatism dial chart.

Re: Making My Own Glasses

#62
post #40

He probably saw the first result incorrectly, opticians almost exclusively use negative cylinders, it seems incredibly unlikely that he would both stumble upon a rare exception using positive cylinders, and that she'd coincidentally get his astigmatism way wrong as well. I share his, uhm, perfectionism regarding optical corrections, and it's led to quite some anxiety. I feel like eye exams here aren't done with a lot…

Some good thoughts. Totally agree with all your points.

Re: Making My Own Glasses

#63
post #57

Misleading title. He tested his own eyesight and ordered glasses online. He didn't make his own glasses. Still an interesting read, just not what I expected from the title and lead.

Eh... he provided custom specifications to a manufacturer.

Apple makes it's own SoCs for the iPhone, only Apple can't make semiconductors. They provide specifications to a manufacturer. Apple makes the iPhone, except it's Foxconn that manufacturers it.

The APU in the Xbox One is made by Microsoft, but it's composed primarily of off the shelf designed CPU and GPU cores from AMD and manufactured by TSMC/GF/.

Re: Making My Own Glasses

#64

For more than 10 years I am going to the same optician for glasses. As a sport pilot, I need to have 2 pairs at all times (one is kept as reserve in the cockpit); changing one to another, with identical "everything", produces a serious discomfort that I cannot explain. I learned to live with the idea that eye sight is complicated. Measurements at different points in time can differ slightly: in the morning just after…

Interesting! For what it's worth, I also learnt that there are quite a few lens manufacturers out there and they all differ slightly regarding lens thickness and refraction properties. That may be another explanation.

And, if your optician is close by and shares your belief that your values vary over time, getting your values checked in different "states" (morning / evening / tired / etc.) can be helpful for deciding on what the "right" values for your glasses may be.

Re: Making My Own Glasses

#65

Wish he included a link for the kit of test lenses he purchased

It's a pretty generic kit sold on ebay from various chinese resellers. It's not too hard to find if you search for "optician kit" or so, price is around 180€ in Germany :)

Re: Making My Own Glasses

#66
post #31

> I have a few seconds to decide whether I see some letters better and this decision will decide which lenses I’ll have in my glasses for the next few years? Absurd! On the contrary, it seems totally logical. If the difference is so small that you can't assuredly decide between two options, either will do. > How can a trustworthy decision be made in this not-real-life scenario of staring at letters on a wall? I want…

> For all the skepticism at others (eye professionals at that), did he checked his enthusiasm for placebo effect?

Yes. I have two pairs of glasses here: The optician-made ones and my self-prescribed ones. I have controlled for the frame - both have the same one.

I see much better with my self-prescribed ones. If you don't believe me, feel free to drop by and we'll do a blinded (heh) test. :)

Re: Making My Own Glasses

#67

> Optician: “Now with this lens, do you see better or worse?” > O: “Honestly, I have no clue. Maybe. Maybe not? The letters look similar but different.” [edit] Reprahsing to make it clearer: will it be possible in the future to measure objectively?

Yes. Last year, I realized I needed glasses, went through two opticians and three pairs of lenses, still wasn't happy, and finally ended up seeking out an office that could measure for free-form lenses (measured objectively with more degrees of freedom in the prescription).

This optician used Zeiss a i-Profiler to make i-Scription lenses (https://www.zeiss.com/vision-care/us/for-eye-care-profession...) They've worked better for me than any of the subjectively-measured prescriptions.

Re: Making My Own Glasses

#68

Fascinating hacker story in an unexpected domain. Thank you! A side note about "getting your numbers"... The author remarks, "she’s not happy to share the measurements with me as she fears I’ll run off and get my glasses made online". This will obviously vary by jurisdiction but what the author describes may be illegal in some places. e.g. where I live, there is a law since 2010 requiring opticians and optometrists "…

In the EU, a GDPR data subject request will get you all the data you want.

Re: Making My Own Glasses

#69

> Optician: “Now with this lens, do you see better or worse?” > O: “Honestly, I have no clue. Maybe. Maybe not? The letters look similar but different.” [edit] Reprahsing to make it clearer: will it be possible in the future to measure objectively?

fwiw, I talked to someone who'd done some research in that area. While using an autorefractor provides you with objective values, predicting the actual values people were most satisfied with was very difficult. Possibly because there's a lot of "post-processing" of visual signals in our brain and that may vary a lot individually.

I totally agree that having an objective way to measure this would be awesome.

Re: Making My Own Glasses

#70
post #57

Misleading title. He tested his own eyesight and ordered glasses online. He didn't make his own glasses. Still an interesting read, just not what I expected from the title and lead.

Agreed. This was nowhere close to the cool hacker story I was expecting.
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