Purple objects absorb light at various wavelengths depending on the specific shade of purple. In the visible light spectrum, purple is typically associated with shorter wavelengths towards the blue end. Specifically, violet and indigo shades of purple absorb light in the range of approximately 380 to 450 nanometers (nm).
When white light, which contains a mixture of all visible wavelengths, illuminates a purple object, the object absorbs most of the other colors in the spectrum but selectively absorbs and reflects the shorter wavelengths associated with purple. The absorbed light energy contributes to the object's color perception, while the reflected or transmitted light gives the object its visible appearance as purple to our eyes.