| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device which generates white light by using an excitation light source and a phosphor layer.SOLUTION: A lighting device includes: a light source 21; a phosphor layer 32; a polarization separating element 50A placed in an optical path between the light source 21 and the phosphor layer 32; a first retardation plate 26 placed in an optical path between the polarization separating element 50A and the phosphor layer 32; an excitation light reflection part which reflects at least a part of light BLc of a first wavelength band emitted by the first retardation plate 26 in the manner that the light is made incident to the polarization separating element 50A via the first retardation plate 26; a fluorescent light reflection part which reflects fluorescent light YL emitted by the phosphor layer 32 in the manner that it is made incident to the polarization separating element 50A; and a first reflection part 60 which reflects at least a part of light BLs' that progresses from the excitation light reflection part to the light source 21 via the polarization separating element 50A in the manner that the light is made incident to the polarization separating element 50A. |
