Method for determining an optical property (μ a, μ s, μ s ', g) of a sample, comprising the following steps: - illumination of a surface of the sample with the aid of a light beam, so as to form, on the surface of the said sample, an elementary illumination zone, corresponding to the part of the said surface illuminated on the said sample, - detection of N optical signals (52 1, 52 2, 52 3, 52 4, 52 n), backscattered by the sample, each optical signal emanating from the surface of the sample, at the level of an elementary detection zone (28 n), at a distance (D 1, D 2, D 3, D 4, D n), termed the backscattering distance, from the said elementary illumination zone, N being an integer greater than 1, so as to form as many detected signals (S 1, S 2, S 3, S 4, S n), each elementary detection zone (28 n) being separated from the said elementary illumination zone, - determination of at least one optical property (p) of the sample, by comparison between: ▪ a function (R 1, R 2, R 3, R 4, R n) of each signal thus detected (Si, S 2, S 3, S 4, S n), ▪ and a plurality of estimations of the said function (R 1,p model, R 2,p model, R 3,p model, R 4,p model, R n,p model), each estimation being carried out by considering a predetermined value of the said optical property (p), the method being characterized in that - during the said detection step, at least one backscattering distance (D 1, D 2) separating an elementary detection zone (28 1, 28 2) from the said elementary illumination zone, is less than 200 μm. - illumination of a surface of the sample with the aid of a light beam, so as to form, on the surface of the said sample, an elementary illumination zone, corresponding to the part of the said surface illuminated on the said sample, - detection of N optical signals (52 1, 52 2, 52 3, 52 4, 52 n), backscattered by the sample, each optical signal emanating from the surface of the sample, at the level of an elementary detection zone (28 n), at a distance (D 1, D 2, D 3, D 4, D n), termed the backscattering distance, from the said elementary illumination zone, N being an integer greater than 1, so as to form as many detected signals (S 1, S 2, S 3, S 4, S n), each elementary detection zone (28 n) being separated from the said elementary illumination zone, - determination of at least one optical property (p) of the sample, by comparison between: ▪ a function (R 1, R 2, R 3, R 4, R n) of each signal thus detected (Si, S 2, S 3, S 4, S n), ▪ and a plurality of estimations of the said function (R 1,p model, R 2,p model, R 3,p model, R 4,p model, R n,p model), each estimation being carried out by considering a predetermined value of the said optical property (p), the method being characterized in that ▪ a function (R 1, R 2, R 3, R 4, R n) of each signal thus detected (Si, S 2, S 3, S 4, S n), ▪ and a plurality of estimations of the said function (R 1,p model, R 2,p model, R 3,p model, R 4,p model, R n,p model), each estimation being carried out by considering a predetermined value of the said optical property (p), the method being characterized in that - during the said detection step, at least one backscattering distance (D 1, D 2) separating an elementary detection zone (28 1, 28 2) from the said elementary illumination zone, is less than 200 μm.