Image plane digital holographic detection is an important application of coherent light imaging. However, due to the spatial filtering of coherent transfer function, charge coupled device (CCD) cannot detect the complete image light field when the exit pupil size of the imaging system is small. Moreover, using the current popular theory that the amplitude distribution of the image light field can only be calculated, the image light field with amplitude and phase distribution which is convenient for optical detection can not be reconstructed.A method of designing specific illumination light is proposed based on the analysis of coherent light imaging theory. Using the proposed method, the object plane detection area can be complete imaging by optical system. By combining the hologram of object illumination light with the proposed method, the ideal image light field which is convenient for practical detection can be reconstructed.