Method for determining colorimetric characteristics in reflection of an interference filter, characterised in that it comprises the following steps: - determining (E20, E30) colorimetric coordinates of an object; - determining (E32, E34) at least one colorimetric characteristic (C* f) in reflection of the interference filter depending on the determined colorimetric coordinates while respecting an so-perception law. wherein the colorimetric characteristic (C* f) in reflection is determined depending on a reflectance (R Vf) desired for the interference filter, wherein the colorimetric coordinates of the object include a lightness level (L*) of the object and a colour saturation value (C*) of the object, and wherein the step of determining at least one colorimetric characteristic (C* f) in reflection of the interference filter comprises the following substeps: - converting the lightness level (L*) of the object into an equivalent reflectance (R Veq); - determining a colour saturation value (C* f) in reflection of the interference filter depending on the reflectance (R Vf) desired for the interference filter, on the equivalent reflectance (R Veq) and on the colour saturation value (C*) of the object while respecting the iso-perception law such that the ratio of the colour saturation value (C* f) in reflection of the interference filter to the desired reflectance (R Vf) is equal to the ratio of the colour saturation value (C*) of the object to the equivalent reflectance (R Veq). - determining (E20, E30) colorimetric coordinates of an object; - determining (E32, E34) at least one colorimetric characteristic (C* f) in reflection of the interference filter depending on the determined colorimetric coordinates while respecting an so-perception law. wherein the colorimetric characteristic (C* f) in reflection is determined depending on a reflectance (R Vf) desired for the interference filter, wherein the colorimetric coordinates of the object include a lightness level (L*) of the object and a colour saturation value (C*) of the object, and wherein the step of determining at least one colorimetric characteristic (C* f) in reflection of the interference filter comprises the following substeps: - converting the lightness level (L*) of the object into an equivalent reflectance (R Veq); - determining a colour saturation value (C* f) in reflection of the interference filter depending on the reflectance (R Vf) desired for the interference filter, on the equivalent reflectance (R Veq) and on the colour saturation value (C*) of the object while respecting the iso-perception law such that the ratio of the colour saturation value (C* f) in reflection of the interference filter to the desired reflectance (R Vf) is equal to the ratio of the colour saturation value (C*) of the object to the equivalent reflectance (R Veq). wherein the colorimetric characteristic (C* f) in reflection is determined depending on a reflectance (R Vf) desired for the interference filter, wherein the colorimetric coordinates of the object include a lightness level (L*) of the object and a colour saturation value (C*) of the object, and wherein the step of determining at least one colorimetric characteristic (C* f) in reflection of the interference filter comprises the following substeps: - converting the lightness level (L*) of the object into an equivalent reflectance (R Veq); - determining a colour saturation value (C* f) in reflection of the interference filter depending on the reflectance (R Vf) desired for the interference filter, on the equivalent reflectance (R Veq) and on the colour saturation value (C*) of the object while respecting the iso-perception law such that the ratio of the colour saturation value (C* f) in reflection of the interference filter to the desired reflectance (R Vf) is equal to the ratio of the colour saturation value (C*) of the object to the equivalent reflectance (R Veq). - converting the lightness level (L*) of the object into an equivalent reflectance (R Veq); - determining a colour saturation value (C* f) in reflection of the interference filter depending on the reflectance (R Vf) desired for the interference filter, on the equivalent reflectance (R Veq) and on the colour saturation value (C*) of the object while respecting the iso-perception law such that the ratio of the colour saturation value (C* f) in reflection of the interference filter to the desired reflectance (R Vf) is equal to the ratio of the colour saturation value (C*) of the object to the equivalent reflectance (R Veq).