[Leica] Why is the retina curved?

[simon.apekop at gmail.com (simon jessurun)]

No that's fine.allways  assumed that the plane offocus was flat since
flatness of field is so often mentioned in lens tests.
Thx
Simon

On Tue, Dec 15, 2009 at 12:48 AM, Lawrence Zeitlin <lrzeitlin op 
gmail.com>wrote:

> Because the plane of sharpest focus of a simple lens is on the surface of a
> sphere. Flat film planes are a residue of photography's past when emulsions
> were coated on glass plates. It also makes it easier to change film. Curved
> film planes are used in both simple cameras and complex telescopes to
> provide sharper images. The Minox camera uses a film plane curved in two
> directions but requires a concave pressure plate to force the film into the
> right shape. Some astrophotographic telescopes coat the emulsion on a
> curved
> sheet of glass configured to lie in the plane of the mirror's sharpest
> plane
> of focus. But as far as the eye is concerned, the high resolution area, the
> fovea, is only 3 mm in diameter and the curvature would be very slight. The
> retina is curved because it covers the rear of the inside surface of the
> eyeball which is itself almost spherical so it can rotate in the eye
> socket.
>
> I'm sure that's more than you wanted to know.
>
> Larry Z
>
>
> Le 14 d?c. 09 ? 21:09, simon jessurun a ?crit :
>
>
>
> This article made me wonder why is the retina curved and is the film
>
> plane
>
> in a camera flat?
>
>
>
> http://www.newscientist.com/article/dn18275-flexible-solar-cell-implant-could-restore-vision.html
> <
> http://www.newscientist.com/article/dn18275-flexible-solar-cell-implant-could-restore-vision.htmlbest,simon
> >
>
> best,simon<
> http://www.newscientist.com/article/dn18275-flexible-solar-cell-implant-could-restore-vision.htmlbest,simon
> >
>
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