Touch panel display device and driving method thereof
AssigneeLG Display Co., Ltd.
InventorsIn Ho AHN, Min Ho SOHN, Deuk Su LEE, Kyo Hyuck CHOO
Life of this patent
Estimating the term…
Abstract
A touch panel display device and a driving method thereof are disclosed. The touch panel display device and the driving method thereof sense illumination of external light using a photo-sensor formed on a touch panel, and control a PWM duty of a light source suited to each mode when the sensed illumination of external light corresponds to illumination in a gray zone to be a difference between the illumination of light created by the light source and that of external light, thereby improving touch recognition capability in a gray zone.
Claims8
A touch panel display device comprising:
- a touch panel on which a photo-sensor sensing external light is formed;
- a backlight unit having a light source creating light to be irradiated to the touch panel;
- a readout circuit unit sensing illumination of the external light entered from the photo-sensor to remove noises to be introduced in the entered illumination of the external light, and converting and outputting the entered illumination of the external light into a digital signal;
- an illumination sensing area selector receiving an output signal of the readout circuit unit and selecting at least one of a plurality of divided areas of the touch panel;
- an area average calculator calculating an average of the sensed illumination of the external light from the photo-sensor according to the area selected by the illumination sensing area selector;
- a weight average calculator applying a weight to the calculated average from the area average calculator to calculate an average during several frames;
- a memory unit outputting a PWM duty corresponding to the calculated average to which the weight is applied from the weight average calculator;
- a PWM signal generator generating a PWM signal with the PWM duty output from the memory unit;
- and
- a lamp driving voltage generator generating a lamp driving voltage corresponding to the PWM signal generated by the PWM signal generator to control the light source of the backlight unit.
A method of driving a touch panel display device including a touch panel on which a photo-sensor sensing external is formed, and a backlight unit having a light source creating light to be irradiated to the touch panel, comprising:
- sensing illumination of external light entered from the photo-sensor to remove noises to be introduced in the entered illumination of the external light, and converting and outputting the entered illumination of the external light into a digital signal;
- dividing the touch panel into a plurality of divided areas and selecting at least one of the plurality of divided areas;
- calculating an average of the sensed illumination of external light to be converted into a digital signal according to the selected area;
- applying a weight to the calculated average to calculate an average during several frames;
- outputting a PWM duty corresponding to the calculated average to which the weight is applied;
- generating a PWM signal with the PWM duty;
- and
- generating a lamp driving voltage corresponding to the PWM signal to control the light source of the backlight unit.
Dependencies are inferred from the claim text.