Which laser light color is specifically designed to target hemoglobin in red blood cells?

The correct answer is green light, which is specifically designed to target hemoglobin in red blood cells. Green light operates at a wavelength of approximately 510-550 nanometers, making it highly effective in absorbing the hemoglobin present in blood. This absorption capacity is crucial in medical and cosmetic laser treatments, particularly for conditions involving vascular lesions such as rosacea, spider veins, or other forms of excessive redness in the skin.

In contrast, while blue, yellow, and white light may have various uses in different laser applications, they do not have the same level of specificity for hemoglobin as green light does. Blue light typically targets superficial skin conditions, yellow light can be used for general rejuvenation and pigmentation, and white light doesn't possess the focused absorption characteristics needed for targeting hemoglobin effectively. Therefore, green light stands out for its ability to selectively treat vascular issues, benefiting practitioners and patients in aesthetic and medical dermatology.