Digital personal devices such as smartphones and tablets have become necessities in modern life. However, for image sharpness, most digital devices emit blue light of 380-500 nm in the light spectrum, with higher energy.1 In some studies, macular degradation has been shown to result from long-term exposure to these wavelengths.2,3
In daily life, blue light cut off is needed for health reasons in many situations. For instance, yellow dye is often introduced in eye glasses, goggles, liquid crystal displays (LCDs) and light emitting diodes (LEDs).4,5 These additives can be incorporated in optical adhesives for the same purpose. Therefore, optical adhesives are also widely used in the electro-optical, green energy and consumer markets. The adhesives can be found in acrylic, unsaturated polyester, polyurethane, and other resin systems. This article compares a blue light absorber and a yellow solvent dye in optical adhesive applications.