The indispensable information regarding the image reconstruction is derived immediately/para-immediately by the optical synthetic aperture imaging with the immediate/para-immediate u-v coverage with the samples taking from the space frequency domain.The image of the observed object is obtained.The advantages of the immediate/para-immediate observation using the optical synthetic aperture imaging technology with the immediate/para-immediate u-v coverage are introduced.The analysis of imaging for LBT is proceeded as an example.It deduces the point-spread function and optical transfer function of the LBT system based on the algorithm of the Fast Fourier Transform (FFT),convolution and deconvolution.It also discusses the global transform function and its influence on the effect of imaging.It explains the imaging properties of the immediate/para-immediate u-v coverage.With the means of the experimental simulation,it tests and verifies that the global transform function could restore the image of celestial body under the circumstance which fits the condition of the imaging of the para-immediate u-v coverage.