Patent ID: 8766552

Claim:
A light generating device comprising: an LED module that includes a number of LED groups each of which has a number of LEDs, where the LED groups have different types of LEDs respectively, each group having the same type of LEDs; a memory for storing drive current for a number of LED groups, respectively; an LED module driving unit for driving one of the LED groups that is selected, so that the selected LED group emits light; a current controller for controlling the drive current flowing to the LED module driving unit to drive the selected LED group; a temperature sensor for sensing heat created from the selected LED group; an operation unit for calculating the correct drive current when LEDs in the selected LED group emit light, by referring to the drive current for driving the selected LED group and the temperature acquired by the temperature sensor, and transferring the correct drive current to the current controller; and a key input unit for selecting one of the LED groups or a number of LED groups.