Aspheric lenses - Anyone use them for EM?

Source of graphic/info

Issues caused by the spherical lens.
Generally speaking, the spherical lens is thick and the image through the lens will be distorted. While, with the same prescription and index, the aspherical lens is thinner, lighter and more comfortable for wearers. The aspherical lens has a wide vision and the image through the lens is more real and natural. Wearers will not feel tired after wearing aspherical lens for a long time.

A problem with Aspheric lenses is they are expensive and when doing EM the rapid replacement soon adds up, to quote @Jakey,

Does anyone use Aspherical lenses?

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Nice one! I end up scratching my head too since I have no data on this at all. Ooops.

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Almost 20 year ago, I tried aspheric lenses, -6.25 D, Seiko. They were not nearly as good as in the advertisement graphics above. The spatial distortion was just marginally less than with spherical, but at the expense of the clarity in the periphery. During the year I used them, I learned that asperichal lenses are extremely sensitive to correct fitness, i.e. that the optical axis of the lens goes through your eye’s rotational center - othewise the mathematics the aspherics are based on, will be off. After one year of use, I replaced to Spherical lenses, and were much happier with these. The optometrist admitted that probably aspherics are more beneficial for plus lenses, but not so much for minus. (Sorry for not having completed my profile yet. I just felt it important to reply immediately to this topic.)

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Interesting. Wonder how that works?

According to www.optometry.co.uk, “The products we rely on - Part 1”, July 27, 2001:
Ashperics for low and moderate corrections
These allows for use of flatter base curves without degrading the optical performance - both the asphericity and the flattening reducing the thickness. The thickness reduction in plus prescriptions compared with “best form” lenses can be considerable, but for negative lens forms is much less satisfactory as best forms are already relatively flat.
They usually give a similar level of performance to spheric/toric best form, although they are more sensitive to changes in centration and vertex distance. It is difficult to make an exact comparison, as the aberrations present are different in their proportions, and previous patient adaptation is often problematic.

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As far as I know, here in my hometown Vaasa, Finland, they do no longer market Aspheric minus storage (off-the-shelf) lenses. Instead, now tailor-made lenses are available, approx. 400 € /pair. With the frame on your face, in the shop they have camera/computer-aided mesurement devices, by which they measure several distances and angles between the frame and the eyes. The lens can then be tailor-made. For example, www.silmaasema.fi Nulux iDentity V+ for 429 €/pair. The web-page doesn’t explicitly say it, but based on “…very light, very thin, beautiful shape”, it is clear these lenses are aspheric. Thanks to the individual measurements, compared to a storage lens, there will be less problems due to changes in centration, vertex distance and angles. BUT, not only the price is a problem - you can’t DIY those measurements - you will be dependent on the shop.
Conclusion: Better follow the endmyopia method and just use normal spherical lenses. Every fourth month or so, you can change to a thinner, more good-looking lens, with less aberrations. No need for those expensive hi-tech stuff. Take part in the revolution and enjoy!

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Yes, the aspheric design counters pincushion distortion much more thouroughly than barrel distortion, being caused by plus and minus lenses respectively. In other words, no reason to buy these more expensive lenses if we’re replacing them every couple months anyways.

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