This represents a wave with phase α α polarized at an angle θ θ with respect to the x axis. In this case the Jones vector | ψ ψ ⟩ ⟩ = ( cos ⁡ ⁡ θ θ exp ⁡ ⁡ ( i α α x ) sin ⁡ ⁡ θ θ exp ⁡ ⁡ ( i α α y ) ) can be written with a single phase: | ψ ψ ⟩ ⟩ = ( cos ⁡ ⁡ θ θ sin ⁡ ⁡ θ θ ) exp ⁡ ⁡ ( i α α ) .