PHOSPHOR BASED LIGHTING DEVICES AND METHOD OF GENERATING A LIGHT OUTPUT

摘要

The invention provides a lighting device having a photo-excited phosphor layer, with two monochromatic light beams (1, 1a, 1b) that counter propagate within the phosphor layer (2) thereby providing a destructive interference of the excitation light outside the phosphor layer (2). The excitation light source has an output wavelength greater than a peak absorption wavelength of the phosphor. This enables more efficient conversion of light and reduced heating.