910 comprises sense pixels csu 1 csu m as shown in fig9 in the sense pixels csu 1 csu m sense pixels located in the central region of the sensing pixel structure 910 e g sense pixel csu x have greater pixel area than sense pixels located in the peripheral region of the sensing pixel structure 910 e g sense pixels csu 1 csu y csu m thus the peripheral region of the optical lens 510 corresponds to relatively more sense pixels than the central region of the optical lens 510 please refer to fig1 which is a diagram of a sense image sim generated by the sensing pixel structure 910 the sense image sim can be divided into regions r 1 r n in fig1 different regions are depicted by different hatching orientations for example region r 1 is formed by images generated by sense pixels in the upper left corner of fig9 region r 4 is formed of images generated by sense pixels in the lower left corner of fig9 in order to make the resolution the same in all regions r 1 r n of the sense image sim the sensing pixel structure 910 can be designed so that sense pixels nearer to the central region of the sensing pixel structure 910 have larger pixel area and sense pixels further from the central region of the sensing pixel structure 910 have smaller pixel area more specifically when designing sensing pixel structure 910 pixel area area x of sense pixels of the central region of the sensing pixel structure 910 e g sense pixel csu x and pixel area area y of sense pixels of the peripheral region of the sensing pixel structure 910 e g sense.