optical device that employs mini-prisms that focus light at a point or on a line
NOTE 1 The mini-prisms may be concentric circles for point-focus or linear for focus to a line
NOTE 2 Each mini-prism is slightly different in angular shape so the light is focused at the same point or line.
NOTE 3 Fresnel lenses can be fabricated in a flat or curved shape by stamping or extruding plastic sheets |