Lenticular lens

A lenticular lens is an array of lenses, designed so that when viewed from slightly different angles, different parts of the image underneath are shown.

[1][2][failed verification – see discussion] The most common example is the lenses used in lenticular printing, where the technology is used to give an illusion of depth, or to make images that appear to change or move as the image is viewed from different angles.

Lenticular eyeglass lenses have been employed to correct extreme hyperopia (farsightedness), a condition often created by cataract surgery when lens implants are not possible.

To limit the great thickness and weight that such high-power lenses would otherwise require, all the power of the lens is concentrated in a small area in the center.

In appearance, such a lens is often described as resembling a fried egg: a hemisphere atop a flat surface.

[3] A film made of cylindrical lenses molded in a plastic substrate as shown in above picture, can be applied to the inside of standard glasses to correct for diplopia.

The film is typically applied to the eye with the good muscle control of direction.

Screens with a molded lenticular surface are frequently used with projection television systems.

In this case, rather than transparent lenses, the shapes formed are tiny curved reflectors.

As of 2010[update], a number of manufacturers were developing auto-stereoscopic high definition 3D televisions, using lenticular lens systems to avoid the need for special spectacles.

[6] Lenticular lenses were used in early color motion picture processes of the 1920s such as the Keller-Dorian system and Kodacolor.

This is determined by the maximum angle at which a ray can leave the image through the correct lenticule.

The focal length of the lens is calculated from the lensmaker's equation, which in this case simplifies to: where