What is the base curve (BC) lens sunglasses and what is toric lens?

I often see ads in sunglasses: "Turn base 8" "Curve 10 base x 4.5" "Toric Lens".?What does this mean??What is the base curve??What this impacts on the lens??A sunglasses can be better or worse depending on the base curve?

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Answers (4)

04/14/2012

Then, the glasses must have the following settings:?a) Curvature of the frame to follow the curvature face horizontally?2) The vertical frame must have an inclination of approximately 12 degrees inclination PantoscÃƒÂ³pica call, ie, the lower edges of the frame of the face are closer than the upper?3) When the frame has platelets, these must be adjusted so that they are fully supported on the nasal septum, taking into account the height of the frame relative to the center of the pupil?4) rods must have an opening so that no perfect brows and shake or become loose, causing the feeling that the glasses are large?5) Finally, the probe must be adjusted following the curve behind the ears, with a curve + / - 45, so that the frame be secured to the face, without pressure, so that the glasses do not slip over the nose and increase the distance vertex and taking lens of the optical center of the pupil center.?For multifocal eyeglasses, the pre- adjustments must be very strict.

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Justin fergus

11/06/2013

I think this is the feature of the sunglasses. This can't decide the quality of the sunglasses but it can decide whether this pair of sunglasses is fit for your face shape or not. It is the size of the sunglasses. If you don't know what it means, you can ask the salesman to explain this for you. Or if you feel it is uncomfortable to wear this pair of sunglasses, you can change another one. But few people know the features of their face so few people will choose sunglasses according to this information.

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Danielle

11/06/2013

I have found a video that can tell you what does base and prism mean. You can have a look at http://www.youtube.com/watch?v=AqfoMLRLPdY. It seems a little difficult for me to understand that, so you'd better have a look by yourself. Hope this helped!

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maria calderin

11/06/2013

Toric lenses are used to correct astigmatism. Accoding to what Wikipedia said, the toric lens has different optical power and focal length in two orientations perpendicular to each other. One lens surface is shaped like a cup from a torus, while the other one is spherical. You can find toric lenses in glasses contacts or intraocular lenses. If you still can't understand what it is, you can have a look at http://en.wikipedia.org/wiki/Toric_lens. Hope you can have a good understanding of the toric lens.

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Jumpto