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Comment by zaptheimpaler | Hacker News Reader

The US version reminds me of the bad kind of Java.. `GetGlasses` must implement `AbstractMedicalProcedure` with mandatory `waitAroundForAppointment`, `getOpaqueBillFromShittyWebsite`, `checkIfCoveredByInsurance`. `GetGlasses.get()` takes ONLY `AbstractOfficalPrescription` as input, which of course you CANNOT construct directly from the left and right lens power - must go to an 'OptometristFactory`. Probably like 200 lines atleast.

Meanwhile everyone else is like:

    #pass in left_power and right_power directly if you know them.
    def get_glasses(powers=None):
       if not powers:
          powers = eye_exam()
       (left_power, right_power) = powers
       return add_frame(make_lenses(left_power,right_power)) #make_lenses takes optional args for rarer eye conditions

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When I was in China I wanted to get a cheap pair of prescription glasses. So I did, in an underground subway mall. Took 30 minutes. They (definitely not an eye doctor, more of a small shop owner) used a small handheld device to measure my prescription and then told me to come back in 30 minutes after I had chosen frames. I paid $40.

Neat - it looks like handheld ophthalmic auto refractometers are $4k-ish on alibaba.

Ditto. In Beijing there's a multi-story building full of stores selling glasses. I walked around until someone spoke to me in English, they used a gizmo to automatically measure my prescription. I picked out a brand name pair of frames. The salesman told me to come back in an hour.

Voila a cheap (~$40US) spare pair of glasses.

A former optometrist of mine once gave me a 5 minute lecture on how I must buy my glasses from him because he makes no money from doing exams.

Cry me a river... guess ya should have gone into dentistry.

I found that the lenses quality wasn’t as good when buying in Beijing. They have (or just use?) better tech in the states for churning out lenses that aren’t overly heavy or thick. Perhaps it’s just an artifact of the glasses costing a few hundred kuai.

I’ve seen US based manufacturing. There is a mix of material type selection. But there is also a lot of machinery and automation being used. Also stringent QA. Nothing done in an hour was done well, this much I know.

Honestly I'd be highly surprised if producing a single pair of glasses would take more than an hour end-to-end, as long as you aren't grinding them by hand. With modern plastic lenses it's basically a CNC machining operation followed by a couple of polishing steps. There's no reason you can't do a pair with basically no automation aside from the CNC in an hour easily. And that includes sticking them in a lensmeter to check if the prescription matches for QA.

Of course more complex things such as antireflective coatings add a sputtering step to the process which might be a bit much to expect a shop to do in-house.

I will say that the pair of glasses or received was not as good as one I could have bought in the States. The Chinese glasses I got were usable, and I did use them for years, but when they broke and I purchased glasses in the US going through the standard process, I was reminded of how high quality glasses here can be.

This is reminiscent of the principle that marginal improvements become exponentially more expensive as we seek ever more improvement.

Sure I could get a decent pair of glasses in China for $40, but to get a truly great pair of glasses, the increase in cost that comes with that quality will be disproportionate to the quality itself.

This pseudocode reveals another truth: it can be surprisingly hard in many places to get lenses for rarer eye conditions. If you have e.g. mild astigmatism (actually extremely common!), you can expect to be persuaded to leave it uncorrected.

Really? I have astigmatism and got glasses made in Germany, Britain, Singapore and Australia.

Never had anyone trying to convince me to leave it uncorrected.

I'm astigmatic - -2.50 right, -3.25 left - and i have never, ever, had any optician in the UK suggest leaving it uncorrected.

When i wanted contact lenses, i asked about leaving it uncorrected, so i didn't need toric lenses, which come in fewer variations (i don't think there were daily disposable torics at the time, for example). They weren't having any of that.

Yeah, that expired proper prescription wasn't for toric lenses like I (supposedly) had decades ago. That first time they didn't even tell me the lenses had to be inserted at some correct orientation, and I don't remember seeing the marking on the lens, either... though they did tell me the lenses would cost a bit more. What was the point?

Oh wow

Yeah, that takes a while, even with someone explaining it to you

theoretically they should rotate to match the axis if they're slightly out of position, but if it's way out of position it won't.

Not to mention manufacturers have different ways of indicating this (with different degrees of weirdness)

Does it really matter much?

I have it, recently got glasses and it annoys me that in my peripheral vision and while moving things get a little distorted. Glasses without astigmatism correction seem like a valid choice.

I apparently had a very mild case of astigmatism that went undetected for years. It was so mild that it was easy to 'correct' for it by increasing the strength of the lenses. Now that I have the lenses with astigmatism correction life is much better. My eyes do not tire as quickly and I see more clearly at far distances than I used to. Granted I am sensitive to these small differences, but life quality improvement is vast.

It is even worse with strong astigmatism. I have over 3 diopter according to multiple wavefront aberrometer and photokeratoscopy measurements, but the opticians always want to put a 2.5 or even 1.5 cylinder, because they do not believe it can get that high.

I'm -3.25 cylinder for each eye, plus need a prism of 0.5 down in one and 0.5 up in the other. I feel your pain.

> it can be surprisingly hard in many places to get lenses for rarer eye conditions.

Indeed, ZenniOptical sunglasses simply don't come in m prescription. It flat out tells me to select their regular frames and pay for the tinting. Between my astigmatism and my prism in each eye I'm fairly limited.

Or it just gets expensive. Last Friday I was curious about the new Oculus but hate how VR headsets like my friend's Vive shove my glasses into my face or just simply don't fit and looked at inserts for it, the cheapest I could find from the companies that manufacturer the lenses were 98$ per eye.

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