To improve the resolution and the speed of digital holography reconstruction, the space bandwidth product is used to analyze the application range of Fresnel reconstruction algorithm. Analysis results show that once the recording system satisfies the requirements of space bandwidth product, limiting resolution and rapid reconstruction can be obtained by Fresnel reconstruction algorithm. Meanwhile, short recording distance lens-less Fourier transform optical path is one of the configurations satisfying the requirements of space bandwidth product. Importantly, Fresnel reconstruction algorithm still can be used to reconstruct the complex amplitude of the object to be tested at short recording distance. Moreover, through comparing with Fresnel reconstruction algorithm and convolution algorithm, both reconstruction resolutions are improved, and during large value aperture reconstruction, the memory and calculation time required by Fresnel reconstruction algorithm is far lower than that of convolution algorithm.