What is the purpose of hard coat applied to lenses?

The purpose of a hard coat applied to lenses is primarily to provide scratch resistance. This is crucial for maintaining the clarity and longevity of the lenses, as everyday wear and tear can cause scratches that diminish visual quality and necessitate replacement. The hard coat acts as a protective layer that helps shield the lenses from minor impacts, dust, and other abrasive elements that may come into contact with them.

While enhancing color, improving visibility, and increasing weight are aspects associated with lens construction or treatment, they do not directly relate to the function of the hard coat. The hard coat specifically targets the durability and integrity of the lens surface, ensuring that it remains clear and functional through regular usage.