Photo sensor and flat panel display device using thereof

摘要

A photo sensor that is capable of generating a photo sensing signal corresponding only to ambient light by comprehending changes in electrical current depending on the change of temperature and compensating for the electrical current according the change of temperature and a flat panel display device using the photo sensor, and the photo sensor including a photo sensing unit generating a first current corresponding to an ambient light and a second current corresponding to an ambient temperature; a temperature compensating unit including a dark diode generating a third current having a same magnitude as the second current, corresponding to the ambient temperature due to block of light to be incident; and a buffer unit outputting a light sensing signal corresponding to current having the same magnitude as the first current by subtracting the third current generated in the temperature compensating unit from the second current generated in the photo sensing unit.

主权项

1. A photo sensor, comprising: a photo sensing unit generating a first electrical current corresponding to an ambient light and a second electrical current corresponding to an ambient temperature;
a temperature compensating unit comprising a dark diode generating a third electrical current having a same magnitude as the second electrical current, with the second electrical current having an amplitude that varies according to the ambient temperature surrounding the dark diode by blocking of light to be impingent on the dark diode; and a buffer unit outputting a light sensing signal corresponding to a fourth electrical current having the same magnitude as the first current by subtracting the third current generated at the temperature compensating unit from a sum of the first and second currents generated at the photo sensing unit, in which, in the photo sensing unit, a cathode electrode of the photodiode is connected with a voltage of a driving power supply and an anode electrode of the photodiode is connected with a voltage of an initialization power supply; and in the temperature compensating unit, an anode electrode of the dark diode is connected with the voltage of the initialization power supply and a cathode electrode of the dark diode is connected with the voltage of the driving power supply.