Patent ID: 8729812

Claim:
A lighting device, comprising: a light source at least comprising a first light emitting diode unit for outputting light with a first color temperature and a second light emitting diode unit for outputting light with a second color temperature; a color-temperature adjustable module comprising a switching element coupled with a power source and a driving device electrically connected between said switching element and said light source, wherein according to a number of times said switching element is turned on, said driving device generates a first enabling signal to said first light emitting diode unit and/or generates a second enabling signal to said second light emitting diode unit, wherein said first light emitting diode unit provides a first luminance with said first color temperature in response to said first enabling signal, and/or said second light emitting diode unit provides a second luminance with said second color temperature in response to said second enabling signal; and a luminance adjustable module for fine tuning said first luminance and/or said second luminance outputted from said color-temperature adjustable module, thereby slightly increasing or decreasing said first luminance and/or said second luminance.