Backlight module and liquid crystal display device

A backlight module, comprising:

• at least one first light-emitting unit, and each first light-emitting unit includes a first blue light-emitting chip;
• at least one second light-emitting unit, and each second light-emitting unit includes a second blue light-emitting chip, wherein, an emission peak wavelength of the second blue light-emitting chip is greater than an emission peak wavelength of the first blue light-emitting chip;
• a control circuit used for obtaining a blue saturation of a display picture of a liquid crystal panel that being provided with a backlight by the backlight module, and dynamic adjusting a brightness of the first light-emitting unit and the second light-emitting unit according to the blue saturation;
• wherein, the emission peak wavelength of the first blue light-emitting chip is in a range of 440 nm to 455 nm, the emission peak wavelength of the second blue light-emitting chip is in a range of 460 nm to 470 nm;
• wherein, when the blue saturation is less than or equal to a preset saturation threshold, the control circuit controls the brightness of the first light-emitting unit and the second light-emitting unit by a first mode;
• when the blue saturation is greater than the preset saturation threshold, the control circuit controls the brightness of the first light-emitting unit and the second light-emitting unit by a second mode;
• wherein, the brightness of the first light-emitting unit under the first mode is greater than the brightness of the first light-emitting unit under the second mode, and the brightness of the second light-emitting unit under the first mode is less than the brightness of the second light-emitting unit under the second mode.