Method for characterizing the appearance of a particular object, for predicting the appearance of an object, and for manufacturing an object having a predetermined appearance which has optionally been determined on the basis of a reference object
AssigneeDow Global Technologies LLC
InventorsJan C. Torfs, Gerrit J. Brands, Eric G. Goethals, Evelien M. Dedeyne
Life of this patent
Estimating the term…
Abstract
The surface contribution to appearance of an object is characterized using a plurality of viewing and illumination angles. The color determining and surface contribution are determined to aid in the predicting of the appearance of an object as well as matching an object to another object.
Claims25
A method for characterizing the surface contribution to the appearance of an object;
- the method comprising the step of determining the surface contribution to appearance or the surface reflection k1(w,h,i), from a plurality of reflectance values Rm(w,h,i) which are established for at least one light frequency w and a plurality of combinations of viewing (h) and illumination (i) angles.
A method for predicting the appearance of an object wherein the method comprises predicting the appearance of the object at predetermined viewing and illumination angles based on the color determining parameters of the material and the surface contribution to appearance or plurality of reflection values k1(w,h,i) for a predetermined plurality of combinations of viewing and illumination angles.
A method for matching the appearance of an object with a reference object;
- the method comprising the steps of:
- A. measuring or otherwise selecting the reflectance values of the reference object at a plurality of predetermined viewing (h) and illumination (i) angle(s);
- B. measuring the reflectance value Rmtest(w,h,i) of a test object manufactured from a pre-selected material having a pre-selected amount and type of colorant(s) and/or other additive(s) using pre-selected method of manufacture;
- C. calculating the surface contribution to appearance or the reflection value (s) k1(w,h,i) of the test object from reflectance value(s) Rp(w,h,i) associated with the predetermined viewing (h) and illumination (i) angle(s);
- D. making a sample object predicted to have the reflectance value(s) Rp(w,h,i) from the k1(w,h,i) values measured in C. with the desired reflectance value(s) Rmref(w,h,i) of the reference object;
- E. comparing the reflectance values measured on the sample object from step D. with that of the reflectance value of the reference object;
- and
- F. repeating, as desired, steps B, C, D, and E using the amount or type of colorants, other additives or manufacturing process until the appearance match between the first and second object is acceptable.
The method of claim 23 wherein the method is carried out for a plurality or a range of values for the frequency (w).
The method of claim 25 wherein n the surface reflection value (s) k1(w,h,i) is calculated from a knowledge of the surface topology of the given texture of the object.
Dependencies are inferred from the claim text.