US 5,335,187 A · Method and apparatus for dyeing and color matching lenses

Abstract

A color matching and lens dyeing apparatus and method in which a color is chosen, the color is converted to a numerical value on the basis of its transmissivity at different wavelengths of light and the transmissivity is converted into a lens dyeing prescription. The numerically determined information on the desired color is processed by a computer to obtain the proper compound ratios, dye baths and dyeing times. A set of standard dye baths are prepared and lenses are dyed therein. The dyed lenses are measured for transmissivity at different wavelengths and the transmissivity data is stored in a computer. To prepare a dying prescription, a target set of transmissivity characteristivity is selected and the transmissivity data of the standard dye baths is combined to obtain a dyeing prescription to obtain a dyed lens having the same transmissivity characteristics as the target.

Claims22

Dependent claims

A method of dyeing a starting lens so that it will have substantially the spectral transmittance characteristics of a target lens, comprising:

measuring the spectral transmittance characteristics of a starting lens and a target lens;
preparing a set of standard dye baths for dyeing the starting lens;
dyeing sample lenses in each of the standard dye baths to yield dyed sample lenses;
measuring the spectral transmittance characteristics of the dyed sample lenses and obtaining spectral transmittance characteristics data corresponding to the dyeing characteristics of the respective standard dye baths, including the dyeing concentration of the dye baths as a function of a dyeing time;
formulating a dyeing prescription for dyeing the starting lens, including selecting dye baths for dyeing the starting lens from among the set of standard dye baths, and selecting appropriate dyeing times for the selected dye baths, by adding the spectral transmittance characteristics of dye baths from the set, to the spectral transmittance characteristics of the starting lens in a manner so that the sum of the spectral transmittance characteristics substantially match the spectral transmittance characteristic of the target;
and
dyeing the starting lens with the selected dye baths for the specified dyeing times as set forth in the formulated dyeing prescription.

4 more elements

Dependencies are inferred from the claim text.

Method and apparatus for dyeing and color matching lenses

Life of this patent

Method and apparatus for dyeing and color matching lenses

Life of this patent

Abstract

Claims22