Patent No. EP3685219 (titled "Optical Lens For Correcting Color Vision") was filed by Essilor on Sep 19, 2018. The application was issued on Nov 22, 2023.
Optical lens for correcting color vision deficiency through selective transmission characteristics, particularly for individuals with color vision deficiency. The lens comprises a selective filter, like an absorptive magenta dye, which is able to cut in the green of the visible spectrum. The filter is combined with a color-balancing component to partially offset the pinky appearance of the lens. The lens achieves a transmission curve characteristic of 8-18% in the visible spectrum, with a specific transmission curve that optimizes color perception while maintaining cosmetically acceptable appearance.

Patent oppositions filed by competitors challenge the validity of a granted patent. These oppositions are typically based on claims of prior art, lack of novelty, or non-obviousness. They are a key part of the process for determining a patent's strength and enforceability.
The dossier documents provide a comprehensive record of the patent's prosecution history - including filings, correspondence, and decisions made by patent offices - and are crucial for understanding the patent's legal journey and any challenges it may have faced during examination.