At present, there is a problem of uneven brightness of the out-coupling grating of the holographic waveguide display system in the field of AR. In this paper, a holographic grating with a diffractive efficiency gradient is designed and fabricated to further improve the brightness uniformity of out-coupling grating in the display optical path. Based on theoretical analysis and discussion, this paper proposes a scheme of moving the shutter to realize the change of the exposure time of the holographic plate by divisional region, so that the diffraction efficiency of the obtained holographic grating has a gradual characteristicThe final experimental results are studied and analyzed. The results show that the uniformity of the exit pupil brightness of the coupled grating in the system increases from 28.57% to 57.14%. Therefore, the photographic optical path and exposure method of the holographic optical element used in this paper can effectively improve the uniformity of the exit pupil brightness of the holographic waveguide coupling out grating.