A direct analysis method is proposed based on the use of all the components of the Stokes vector defined as four functions of the wave vector k⇒: I||(k⇒)=c/(4π)E||E||*, I⊥(k⇒)=c/(4π)E⊥E⊥*, I3(k⇒)=c/(4π)E||E⊥*, I4=I3*. Here the E|| and E⊥ are two components of the electric field vector which are lying in the plane of scattering and in the perpendicular plane, respectively. The asterisk denotes complex conjugation, c is the speed of light. If a comet is at a heliocentric distance R and the scattering angle is θ then one can get the integral autocorrelation tensor of the dipole momentum d⇒ distributed within the cloud of cometary dust. This tensor has only four independent components: D||(ρ⇒)=R2/(2π2c)∫(I||-I⊥cos2θ)sin-2θexp(-ik⇒·ρ⇒)k-4d3k⇒; D⊥(ρ⇒)=R2/(2π2c)∫I||exp(-ik⇒·ρ⇒)k-4d3k⇒; D∘(ρ⇒)=R2/(2π2c)∫I3exp(-ik⇒·ρ⇒)k-4d3k⇒. Therefore, there are four independent functions of the correlation shift ρ⇒. If the solar light is scattered by a dust cloud one can right down four relationships: Dij(ρ⇒)=Σ∫d⇒i(r⇒+ρ⇒)d⇒j*(r⇒)d3r⇒. In fact, the D-tensor is a single quantity that can be obtained directly from observations. Unfortunately, even this first step of analysis of polarimetric data is difficult because the Stokes vector is usually unknown for all wavelengths and all scattering angles. It means that any interpretation of polarimetric data contains an uncertainty because it is necessary to guess the behavior of the Stokes vector in the whole 3-dimensional k⇒-space. Therefore, a lot of a priori information is necessary to perform a complete interpretation of polarimetric data. An advantage of the proposed approach is its independence on the shape and morphology of the dust grains. The method proposed can be used, for example, to check the sensitivity of a model of the scatterer obtained from a solution of the direct problem to the choice of dust particle parameters.