Lens dyeing method and apparatus for producing dyeing base body for dyeing lens

A lens vapor deposition transfer dyeing method of dyeing a surface area of a spectacle lens with almost uniform color density, the lens having a large difference between a distance from a dyeing base body to a central portion of the lens surface area and a distance from the dyeing base body to a peripheral portion of the lens surface area, the method comprising the steps of:

• a. selecting a method of forming a dye applied area on the dyeing base body with almost uniform color density changing from a central portion to a peripheral portion of the dye applied area in a stepwise or linear manner, the step (a) including selecting dye application with color density changing that is lower in the peripheral portion than in the central portion when the lens surface area to be dyed is a concave surface and dye application with color density changing that is higher in the peripheral portion than in the central portion when the lens surface area to be dyed is a convex surface;
• b. entering dyeing information including color information in a computer, and obtaining dye application data for a printer to change the color density in a stepwise or linear manner from the central portion to the peripheral portion of the dye applied area having a diameter larger than that of the lens surface area to be dyed based on the entered dyeing information;
• c. applying a dyeing ink containing a sublimable dye by the printer onto one surface of the dyeing base body based on the dye application data to form the dye applied area on one surface of the dyeing base body;
• d. placing the dyeing base body and the lens so that the dye applied area formed surface and the lens surface area face each other in noncontact relation and heating the dyeing base body under substantially a vacuum condition to deposit the dye of the dye applied area onto the lens surface area;
• and
• e. heating the deposited dye to fix the dye on the lens surface area.