Based on the construction of flow-field theoretical model of pulsed gas in atomic layer deposition (ALD), the variation trend of precursor concentration in the ALD process is analyzed, and an optimized deposition area in the ALD chamber is obtained. Based on this, the uniformity experiment of Al2O3 and TiO2 films on the hemispheric substrate is conducted. The experimental results show that the maximum inhomogeneities of the Al2O3 and TiO2 films in the best optimized area are 1.81% and 1.74%, respectively, which decrease by 47.1% and 50.8%, respectively, compared with those in the unoptimized areas. When the angle θ between the incident laser and the hemispheric central axis is 0°, the reflectivity of the prepared antireflection films at 550 nm reaches a minimum value of 0.04%; when θ is 60°, the reflectivity reaches a maximum value of 0.5%. There exist shifts with different agrees in the reflectance curves at other places, and the shift reaches a maximum value of 6 nm when θ is 60°.