Ruler V1:

Cylindrical Fresnel lens

19mm FL 18mm width

Cylindrical fresnel lenses are most typically used for collimating a linear source, such as a linear array of LEDs. They're used in barcode readers.

Hexagonal microlens array

1.5mm ROC, 1mm spacing

This type of lens array is used in Virtual Reality imaging systems and integral imaging aka 3-D displays. Microlens arrays are also used as diffusers.

Constant groove depth Fresnel

36mm FL 18mm diameter

On axis performance is similar to a conventional lens, but the Fresnel lens is lower profile (thinner) and lighter

Aspheric lens

36mm FL 18mm diameter

Does not exhibit spherical aberration or significant distortion, allowing optimal collection of on-axis collimated light, or collimation of light from a point source.

View all four rulers
DSCN0716-main ruler image_edit
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IMG_5978 - fresnel and asphere_edit
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