1. An image reconstructing method comprising: detecting an interference pattern with a detector having a plurality of regions, each region including a first sub-region and a second sub-region of which sensitivity is different from the first sub-region, the interference pattern formed by interference of a reference beam and an object beam, the object beam including information about an object; dividing the interference pattern into a first interlaced interference pattern and a second interlaced interference pattern respectively corresponding to the interference pattern detected by the first and second sub-regions of the detector; obtaining a first Fourier spectrum of the first interlaced interference pattern by performing a Fourier transform on interlaced interference signals detected by the first sub-regions of the detector, the first Fourier spectrum including a zeroth-order spectrum, a first-order spectrum, and a replica of the first-order spectrum of the interlaced interference signals detected by each of the sub-regions; obtaining a second Fourier spectrum of the second interlaced interference pattern by performing a Fourier transform on interlaced interference signals detected by the second sub-regions of the detector, the second Fourier spectrum including a zeroth-order spectrum, a first-order spectrum, and a replica of the first-order spectrum of the interlaced interference signals detected by the second sub-regions; extracting, using a band-pass filter, the first-order spectrum from each of the first Fourier spectrum and the second Fourier spectrum; obtaining first amplitude data by performing an inverse Fourier transform on the first-order spectrum extracted from the first Fourier spectrum; obtaining second amplitude data by performing an inverse Fourier transform on the first-order spectrum extracted from the second Fourier spectrum; selecting, for each of the first and second sub-regions of the detector, one amplitude value lower than a threshold value out of the first amplitude data and the second amplitude data; and reconstructing an image of the object using the selected amplitude values lower than the threshold value, wherein, for each of the first and second sub-regions of the detector, the processor replaces the first amplitude data and the second amplitude data with the selected one amplitude value lower than the threshold value to reconstruct the image of the object.