A pixel array comprises at least one long exposure pixel, short exposure pixel, and a control circuit. The long exposure pixel comprises a first photodiode to generate charges, a first image signal generating module for generating a first image sensing signal; and a first transfer switch device for passing the charges to the first image signal generating module via a first transfer control signal. The control circuit sets the first transfer control signal to be a first predetermined control voltage when the long exposure pixel is in an long exposure phase, and then sets the first transfer control signal to be a second predetermined control voltage when the short exposure pixel is in a short exposure phase.