Ink that tends to change color or vary optically as the angle of lighting changes is called:

Ink that tends to change color or vary optically as the angle of lighting changes is called:

• A. hologram (kenogram and infogram)
• B. Optically Variable Ink (OVI)
• C. Watermark
• D. UV ink

Answer: (A)

Angle-dependent color changes are a hallmark of holographic security features. A hologram is created with microstructures that diffract light, so when you tilt or rotate the surface, the image and its colors shift. This dynamic optical effect, often used on currency and secure documents, helps verify authenticity and is why subtypes like kenograms and infograms are described as holographic features. Watermarks rely on light transmission and don’t change with angle in the same way, UV ink glows only under UV light, and optically variable ink does shift color with viewing angle as an ink, but the distinctive, image-bearing surface described here is the hologram.

Angle-dependent color changes are a hallmark of holographic security features. A hologram is created with microstructures that diffract light, so when you tilt or rotate the surface, the image and its colors shift. This dynamic optical effect, often used on currency and secure documents, helps verify authenticity and is why subtypes like kenograms and infograms are described as holographic features. Watermarks rely on light transmission and don’t change with angle in the same way, UV ink glows only under UV light, and optically variable ink does shift color with viewing angle as an ink, but the distinctive, image-bearing surface described here is the hologram.