Fresnel Lens Limitation
Question:
In the part of aberration of lens in convex lens, Fresnel lens is
used to solve the problem. But it is said that Fresnel lens is of
'poor optical quality'. What does it mean? Isn't it
converge light back to focus and sharp image can be formed? Or is
it related to the 'rough surface' situation which we
can't see the reflection clearly?ject?
Answer:
The Fresnel lens avoids the spherical aberration problem but
superimposes an image of the lens itself on the image, sort of
the 'rough surface' situation you describe.