Based on design feature of Glan-Taylor prism,and by using Snell′s law and equal thickness interference,the distribution of transmitted light of an air-spaced polarizing prism with the incidence of collimated light beam and convergent wave were studied as a function of azimuth and incident angle.Experiments accordingly were conducted,and both theoretical and experimental results indicated that equal visibility and width of fringe were got with the incidence of collimated light;unequal visibility and width of fringe were got with the incidence