>> Product Description
Fresnel lens design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. A Fresnel lens can capture more oblique light from a light source, thus allowing the light from a lighthouse equipped with one to be visible over greater distances.
The Fresnel lens reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections. An ideal Fresnel lens would have an infinite number of sections. In each section, the overall thickness is decreased compared to an equivalent simple lens. This effectively divides the continuous surface of a standard lens into a set of surfaces of the same curvature, with stepwise discontinuities between them.
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Picture show of our fresnel lens
>> Specification
Specification of our optical windows as follow:
| Range of diameter |
Dia. 0.7mm-Dia. 400mm |
| Range of curve radius |
R1.5-R∞ etc. |
| Tolerance of diameter |
+/-0.1, +/-0.01, +/-0.005 etc. |
| Surface accuracy |
Λ, 1/2λ, 1/4λ, 1/10λ etc. |
| Tolerance of Thickness |
+/-0.1, +/-0.05, +/-0.01 etc. |
| Centration |
+/-2′, +/-1′ etc. |
| Aperture N |
5, 1 etc. |
| Irregularity ΔN |
2, 1, 0.5, 0.2 etc. |
| Surface quality |
60/40, 40/20, 20/10, 10/5 etc. |
| Material |
PMMA or other materials |
| Length tolerance |
+/-0.01 |
| Width tolerance |
+/-0.01 |
| Center thickness tolerance |
0.005mm |
| Surface flatness |
< Lambda to lambda/20 |
| *Parallelism |
< =1min -- 2sec |
>> Company Introduction
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Related Products
VY Optics could also manufacture and design other optical elements, including achromatic lens, dome lens, filter, prism, ball lens, cylindrical lens, optical mirrors, spherical lens and rod lens, we can fabricate high-precision lens as per your requested.
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FAQ
Q:
Do you provide samples? Is it free or charged?
· We'd like to supply samples for free if we have it in stock, but we don't pay freight.
Q:
How long is your delivery time?
· Regarding inventory, it is 3 working days;
· For customized one, it's about 15-25 working days, depended on exact quantity and order date.
Q:
Is it possible to customize special lens?
· Yes, to customize special optical element and coating are available here.
Q:
How to pay?
· T/T, Alibaba online assurance payment, MoneyGram, West Union, Paypal and so on.
Q:
How to ensure the safety of payment?
· VY Optics is a reliable supplier not only audited on Alibaba, but also on Made-in-China, reputation and quality is life of our company, and we support Alibaba Trade Assurance.
Q:
How do you ship goods?
· Low value sample: EUB, E Express of China Post, which is cheap;
· Light weight parcel: DHL, FedEx, TNT, UPS, EMS, SF Express, China Post;
· Heavy cargo: by air or by sea, ship on pallet.
Our company enjoy a considerable discount owing to long-term cooperation with courier company.
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