Answer
Eyeglasses, camera lenses, and binoculars with antireflective coatings often look faintly purple because of the way the coating is applied. Antireflective coatings are designed to reduce glare and reflections by absorbing certain wavelengths of light. These coatings are typically applied using a process called physical vapor deposition, in which a thin film of material is deposited onto the lens surface. The film is made up of layers of different materials, each with a different index of refraction. The different layers of material can cause light to interfere with itself, which can result in the reflection of specific wavelengths of light.
In the case of antireflective coatings, the faint purple color is caused by the reflection of specific wavelengths of light in the violet and blue range of the spectrum. This is why the coating appears purple. This is a relatively common property of the antireflective coatings, and it is not a defect or problem with the glasses, camera lens or binoculars.
Work Step by Step
Eyeglasses, camera lenses, and binoculars with antireflective coatings often look faintly purple because of the way the coating is applied. Antireflective coatings are designed to reduce glare and reflections by absorbing certain wavelengths of light. These coatings are typically applied using a process called physical vapor deposition, in which a thin film of material is deposited onto the lens surface. The film is made up of layers of different materials, each with a different index of refraction. The different layers of material can cause light to interfere with itself, which can result in the reflection of specific wavelengths of light.
In the case of antireflective coatings, the faint purple color is caused by the reflection of specific wavelengths of light in the violet and blue range of the spectrum. This is why the coating appears purple. This is a relatively common property of the antireflective coatings, and it is not a defect or problem with the glasses, camera lens or binoculars.
