Optical system and lighting device

Abstract

An optical system () is disclosed comprising a plurality of solid state lighting elements (″) belonging to different groups, wherein solid state lighting elements of different groups produce luminous outputs having different spectral compositions, a collimator array () comprising a plurality of domains (″), each domain comprising a plurality of collimators ('), wherein within each domain each collimator is arranged to collimate the luminous output of at least one solid state lighting element such that each domain contains a number of solid state lighting elements arranged in a spatial pattern, said number consisting of a fixed ratio of solid state lighting elements from each group, and wherein said spatial pattern is varied between domains and a lenslet plate () having a first lenslet array on a first surface () facing the collimator array and a second lenslet array identical to the first lenslet array on a second surface () opposing the first surface, wherein each lenslet () of the first lenslet array is aligned with a corresponding lenslet () of the second lenslet array. Each lenslet array is composed of a plurality of unit cells () comprising a plurality of lenslets in a defined pattern, each of said domains being aligned with one of said unit cells. Also disclosed is a lighting device () comprising such an optical system ().