Conventional technology commonly provides a CT tunable illumination apparatus by constituting a plurality of high color
temperature (HCT) lighting devices and low color temperature (LCT) lighting elements. However, not only does the HCT and LCT lighting elements lead the CT tunable illumination apparatus to have a high manufacture cost and be difficult to be fabricated, but also cause that have a limited CT tunable range because the CT adjusting capability is relied on a CT tunable range of the two types of lighting elements. In view of that, the primary objective of the present invention is to provide a luminance and color temperature tunable light source comprising a plurality of HCT lighting elements and a plurality of light conversion units, wherein parts of the HCT lighting elements are connected with one light conversion unit by a light emission surface thereof. In the present invention, one part of the light conversion units comprises only one light conversion film and the other part of the light conversion units comprises two or more light conversion film stacked to each other. By such design, when the HCT lighting elements emit light, the light conversion unit would apply a light conversion process to the light, so as to change the color temperature and the luminance of the light. Therefore, the light source proposed by the present invention succeeds in exhibiting a brightness and color temperature individually-tunable function. |