Aspheric VS Double Aspheric Lenses - Which is better ?

A customer have told me yesterday that he recently tried contact lenses for the first time and was surprised to see his computer screen seems much flatter than what he sees via his specs.
Now he wants to make new specs with Aspheric lenses and wants to know how much difference he can observe/see, between Single Aspheric Lens Vs Double aspheric lens.

His power is -5 and -5.50 with minor cyl and axis i both eyes.

So which would be ideal thing for him? Do he have to pay more for DAS lenses in his case ?


Please Enlighten me.

PS: Customer is Facing Barrel Distortion issue.

Aspheric lenses improve the cosmetics of a pair of glasses by using surface curves that are flatter centrally and progressively flattened (in plus prescriptions) as one moves from lens center to edge.

For patients with astigmatism, double aspheric lenses are recommended.

I would suggest consulting an ophthalmologist is a better option for deciding about the right type of aspheric lenses.

As told, my patient don't want it for cosmetic reasons and he is Myopic having (-) numbers... He just wants to see things as they are: Flat and natural.
Right now he is using non aspheric high index lenses and his monitor etc.. appear slightly curved to him from sides and he has noticed this for the first time after wearing a trial of contact lenses !

The answer is he should definitely go bi-aspheric

I wouldn't want too flat of a base curve, typically found on many of today's lens designs, if we want to reduce barrel or pincushion distortion. If the goal is to increase optical performance as well as reduce distortion, I would use a not too flat spherical front, aspheric/atoric position of wear optimized design, choosing a frame that minimizes the vertex distance, the latter being the only way to significantly reduce distortion.

Hope this helps,

Robert Martellaro

If I remember correctly, you also want to make sure this lens is surfaced. The Rx seems like it could easily be ordered finished, and in that case, the aspheric quality will not be beneficial for vision, only cosmetic. A surfaced aspheric lens will look better and have a wider field of vision.

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Originally Posted by Robert_S

The answer is he should definitely go bi-aspheric

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Okay... but any particular reason to choose tis over Single Aspheric lens ?
PS: asking coz people are very mixed opnion here.

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Originally Posted by Quince

If I remember correctly, you also want to make sure this lens is surfaced. The Rx seems like it could easily be ordered finished, and in that case, the aspheric quality will not be beneficial for vision, only cosmetic. A surfaced aspheric lens will look better and have a wider field of vision.

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What do you mean by Surfaced aspheric lens and aspheric quality wont be beneficial for vision?

The Customer - is facing Barrel Distortion and want to eliminate it. I have already given him a frame with less curves from sides...

A contact lens is so superior in reducing peripheral distortions that I don't think aspheric vs. Non vs double will make that much of a perceivable difference. More likely to be helpful with a sensible frame and a short vertex distance.

Remember...although aspheric lenses reduce thickness and peripheral distortion, they degrade acuity off center...potentially exacerbating another unforseen issue.

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Originally Posted by fjpod

A contact lens is so superior in reducing peripheral distortions that I don't think aspheric vs. Non vs double will make that much of a perceivable difference. More likely to be helpful with a sensible frame and a short vertex distance.

Remember...although aspheric lenses reduce thickness and peripheral distortion, they degrade acuity off center...potentially exacerbating another unforseen issue.

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+1. This is where we come into the "managing patient expectations" portion of our jobs. Vision is going to be different through glasses than through contacts. Period. It will take some getting used to. Period.

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Originally Posted by fjpod

although aspheric lenses reduce thickness and peripheral distortion, they degrade acuity off center

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This is not something I have ever heard. Could you elaborate on this and point me to where I could read about it?

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Originally Posted by fjpod

A contact lens is so superior in reducing peripheral distortions that I don't think aspheric vs. Non vs double will make that much of a perceivable difference.

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The CW is that what can be done on two surfaces can be done on on surface, essentially without compromise.

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Remember...although aspheric lenses reduce thickness and peripheral distortion, they degrade acuity off center...

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Only true (visual degradation) for flatter than recommended best form base curves, not for aspheric and optimized/free-form surface designs.

Best regards,

Robert Martellaro

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Originally Posted by biscusman

What do you mean by Surfaced aspheric lens and aspheric quality wont be beneficial for vision?

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My understanding it that if the lens is molded, and ordered in a a finished lens, the aspheric quality is only to make the lens look better. When an aspheric puck is ground to Rx, there is less peripheral distortion as well as a better looking lens.

We have had issues in the past requiring we take people out of aspheric finished lenses because they do not have the same field of vision.

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Originally Posted by Quince

My understanding it that if the lens is molded, and ordered in a a finished lens, the aspheric quality is only to make the lens look better.

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I would say it varies by manufacturer and intended purpose. Some lower end lenses may be designed only for cosmetics, but stock aspheric lenses from the big boys are going to be designed for optics and cosmetics. Obviously you can't customize it to each person like you could with a FF backside surfaced lens.

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Originally Posted by Kwill212

I would say it varies by manufacturer and intended purpose. Some lower end lenses may be designed only for cosmetics, but stock aspheric lenses from the big boys are going to be designed for optics and cosmetics. Obviously you can't customize it to each person like you could with a FF backside surfaced lens.

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Also, those cosmetics are nothing to sniff at when the power is in the higher pluses.

Today I am wearing my Zeiss Double Aspheric 1.74 purecoat lenses I haven't worn in a year or so. Wow they are sharp. Not quite the peripheral clarity of my IOT FFSV, but darn close and the dead center of vision feels a little better. A great value when sourced as a finished stock lens. My RX is very close to the OP's description as well

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Originally Posted by Tallboy

Today I am wearing my Zeiss Double Aspheric 1.74 purecoat lenses I haven't worn in a year or so. Wow they are sharp. Not quite the peripheral clarity of my IOT FFSV, but darn close and the dead center of vision feels a little better. A great value when sourced as a finished stock lens. My RX is very close to the OP's description as well

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Great to know an actual user review here...

My customer wants to go with Nikon DAS Lenses which are quiet good - After hearing all of the above, i guess i will tell him to go with dual aspheric ! as i couldn't make out any conclusive dicision if he needs a dual AS or Not.

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Originally Posted by AngeHamm

Also, those cosmetics are nothing to sniff at when the power is in the higher pluses.

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Nobody cares about strong hyperopia in lens design. Could you imagine the results they could have via a dual surfaced digitally designed/customized/personalized/whateveristhenextized version of the lenses we will be able to get our hands on?

The best I've seen in this realm has been the zeiss individual 1.74 stuff. I heard hoya was doing it also in Trivex, but I never hung my hat on the Hoya wagon.

Maybe MakeOptics will have it in Poly? I'd be interested.

Does Seiko and their obvious close ties to M-Resins do that stuff? Just started using a lab in Pennsylvania that happens to do Seiko stuff

Also to the previous poster above who recommended talking to an ophthalmologist for recommendations on whether or not to use double aspheric sv lenses are you for real? That was a ruse or a joke right? I just got an RX today from an Ophthalmologist today that hand wrote a request for a D25. She had measured the lip of the bifocal.

Stay in your lane. Contacts are best for peripheral vision, made me become a much better basketball player immediately.

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Originally Posted by Tallboy

Today I am wearing my Zeiss Double Aspheric 1.74 purecoat lenses I haven't worn in a year or so. Wow they are sharp. Not quite the peripheral clarity of my IOT FFSV, but darn close and the dead center of vision feels a little better. A great value when sourced as a finished stock lens. My RX is very close to the OP's description as well

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Who sells these as stock lenses?

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Originally Posted by Neophyte Optician

Who sells these as stock lenses?

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Zeiss