Apparatus and method for dynamically controlling backlight

An apparatus for dynamically controlling backlight source, for receiving a pixel input data to output a pixel output data and a PWM signal, the apparatus comprising:

• an image analysis unit, for receiving the pixel input data, and performing an image analysis to output an image data;
• an information unit, for storing a luminance adjusting data and a PWM adjusting data, wherein a gray level range corresponding to the pixel input data is just divided into two ranges of a low gray level range and a high gray level range, the luminance adjusting data corresponding to the high gray level range is a fixed maximum value while the PWM adjusting data is non-constantly adjusted, and the PWM adjusting data corresponding to the low gray level range is a fixed minimum value while the luminance adjusting data is non-constantly adjusted;
• a table look-up unit, for looking up the luminance adjusting data and the PWM adjusting data to obtain a required pixel luminance data and a required PWM data;
• a PWM adjusting unit, for receiving the required PWM data to output the PWM signal;
• and
• a multiplication unit, for receiving the pixel input data and performing a luminance adjustment according to the required pixel luminance data to output the pixel output data.

A method for dynamically controlling backlight source, for receiving a pixel input data to output a pixel output data and a PWM signal, the method comprising:

• providing an image analysis unit, for receiving the pixel input data, and performing an image analysis to output an image data;
• storing a relation data in an information unit, wherein the relation data comprises a luminance adjusting data and a PWM adjusting data corresponding to a gray level range wherein the gray level range is just divided into two ranges of a low range and a high range;
• performing a luminance calculation according to the image data and the relation data to obtain a required gray level corresponding to a required luminance;
• respectively obtaining a required pixel luminance data and a required PWM data according to the required gray level, wherein the required PWM data is constantly adjusted to a PWM minimum value and the required gray level is non-constantly adjusted when a gray level of the pixel input data is at the low range, wherein the required PWM data is non-constantly adjusted and the required gray level is constantly adjusted to a maximum gray level when the gray level of the pixel input data is at the high range;
• providing a PWM adjusting unit, for receiving the required PWM data to output the PWM signal;
• and
• providing a multiplication unit, for receiving the pixel input data and performing a luminance adjustment according to the required pixel luminance data to output the pixel output data.