NTKJ Optics

Fresnel lenses are a type of lens that has only the curvature flattened to a plane.　Fresnel lenses, though plane, can act as spherical lenses. Since they are essentially flat, Fresnel lenses offer tremendous space- and weight-saving, and also enable focal lengths shorter than their aperture, a feat impossible with spherical lenses.
They are widely used as field lenses for cameras, condenser lenses in overhead projectors, rear projector screens, for optimal gathering of solar energy, lenses in LED lighting, in optical sensors, etc.

A lens array has a multitude of identical individual lenses arranged in a plane. As the name suggests, a fly-eye lens resembles a fly's eye with its many small lenses. These lenses are used to reduce uneven luminance.

A flat cylindrical lens. Condenses or diffuses light in a single direction. Can both diffuse light or condense it into a line, and is used in LED lighting and solar concentration.

Fresnel lenses are a type of lens that has only the curvature flattened to a plane.　Fresnel lenses, though plane, can act as spherical lenses. Since they are essentially flat, Fresnel lenses offer tremendous space- and weight-saving, and also enable focal lengths shorter than their aperture, a feat impossible with spherical lenses.
These Fresnel lenses are designed with the plano side facing the parallel light source. They are used as a light concentrator in solar photovoltaic generation systems, focusing sunlight on high-density solar cell elements to consolidate the solar energy. These lenses are also used in solar furnaces for processing materials at high temperatures.
Because they were designed to condense parallel light, condensing Fresnel lenses with short focal distances can be combined with a sensor, etc. for light-detecting applications.

Prisms are arranged on a flat surface with their angles aligned. They are used to bend incident light in specified directions.　Prisms are commonly used in LCD panel backlight modules, etc. as light entering from one face can be emitted from the surface.