Display device and method of controlling display device

A method of controlling a display device including a solid-state light source driven by a PWM signal, and a light modulation device that modulates light emitted by the solid-state light source in response to an image signal, comprising:

• determining a duty ratio and a current value of the PWM signal;
• outputting a PWM signal having a predetermined current value to the solid-state light source if the duty ratio is less than a predetermined threshold value;
• and
• outputting a PWM signal having a current value more than the predetermined current value and increasing as the duty ratio is increases to the solid-state light source if the duty ratio is equal to or more than the predetermined threshold value.

A display device comprising:

• a solid-state light source driven by a PWM signal;
• a light modulation device that modulates light emitted by the solid-state light source in response to an image signal;
• and
• a signal output unit that:
• determines a duty ratio and a current value of the PWM signal;
• outputs a PWM signal having a predetermined current value to the solid-state light source if the duty ratio is less than a predetermined threshold value;
• outputs a PWM signal having a second current value larger than the predetermined current value if the duty ratio is equal to or more than a second threshold value larger than the predetermined threshold value;
• and
• outputs a PWM signal having a current value less than the second current value and equal to or more than the predetermined current value in response to the duty ratio if the duty ratio is less than the second threshold value and equal to or more than the predetermined threshold value.