aspherical lenses, CP265-25249(CPV, F=265mm), fresnel lens concentrator

Groove pitch of CPV lens is upside down to prevent contamination from dust and other outdoor conditions. CPV Fresnel lenses are 50~ 100% thicker than common Fresnel lenses. Also Groove pitch is wider for high efficiency.
Also we design to use more 3mm Optical PMMA for longer life time and to have 0.5 ~ 1.0mm groove pitch for higher solar concentration. (If groove pitch is density, then quality of image that is maginifed is clearer.If groove pitch is width, then efficince of concentration of light is higher.)
There is three choices for material of CPV lens, Poly visible, Poly visible with UV cut, and SOG. (see Poly material documet for detail)

Technical information

Focal Length (mm) = 265
Size (mm) : 268*249
Groove Pitch (mm) :0.5
Thickness (mm) : 5
Material : PMMA
Type : CPV

 Fresnel lens concentration rate

Groove pitch of CPV is upside down to prevent contamination from outdoor usages.

CPV Fresnel lenses are 50~ 100% thicker than other Fresnel lenses.

Also Groove pitch is wider for high efficiency.

Also we design to use more 3mm Optical PMMA for loner life time and to have 0.5 ~ 1.0mm groove pitch for higher solar concentration.

(If groove pitch is density, then quality of image that is maginifed is clearer.If groove pitch is width, then efficince of concentration of light is higher.)

◈ Refraction of light with Conve and Concave lens

◈ Cone lux diagram (50, 90, 120˚)

The basic functions of the lens to refract light, can spreading or condensing the light emitted from the light source.

Fresnel lens a lighter and thin than convex(concave) lens.

So, when the Fresnel lens used in lighting equipment to make a lighter, smaller apparatus.

◈ Fresnel lens concentration rate

Concentration rate is ratio between area of solar cell and area of Fresnel lens.

Ex) Fresnel lens size 120*120mm → area of lens is 14400mm2
Solar cell size 5*5mm → area of solar cell is 25mm2
Concentration rate is 14400/25 = 576 times

However because of transmittance rate and other obstructs, multiple 80% is reasonable.
Adjusted concentration rate is (14400*0.8)/25 = 460 times

◈ Efficiency and F number

F=focal legnth/Diameter

From F1.2, the efficency is dramatically droped. It shows there is a certain ratio between focal length of fresnel and diameter of lens.

Bigger size Lens is not always the answer.

◈ Comparing transmittance of SOG(Silicone On Glass) and PMMA

Our Optical PMMA has higher transmitive than glass, which is 92~95%, and absorption in visual ray is almost 0%

Optical designing and tooling a mold as customer's needs is always welcome for us.