The problem of a thin sheet containing a slant crack and subjected to a biaxial load is examined by giving the expressions for stresses in a series form, which are equally valid near and far (r<2a) from the crack tip. The progressive importance of the higher-order terms in the series representation for stresses, which were added to the singular and constant ones was demonstrated by giving the isochromatic fringe patterns near and far the crack-tip area. Based on these expressions, a photoelastic determination of the exact values of the complex stress intensity factor was given without necessitating appropriate correction factors and diagrams. The values of SIFs thus determined are valid independently of the polar angle and distance of measurements from the crack tip.