An incoherent image-deblurring method has been developed. We use a new deblurring function that is easier to implement than inverse filter. This function convolving with blurred image in spatial domain can get deblurring image. In this system, extended monochromatic source and extented white light source can be used. Because of the incoherent source, it introduces redundency in the system. So this method offers substantially improved noise performance compared to conventional coherent systems. Theoretical analysis shows that the new deblurring function, is the Fourier transform of inverse filtering function. Experimental results are also given.