A Wood’s lamp is a device that emits ultraviolet (UV) light in the 365 nanometer range and is commonly used by dermatologists to assist in the diagnosis of various pigment and infectious disorders. The examination is performed in a dark room, allowing the Wood’s light to shine directly on the affected area for a few seconds and looking for any changes in color or fluorescence. Normal skin does not fluoresce under the light of a Wood’s lamp. If a fungal or bacterial infection or pigment disorder is present, Wood’s lamp examination can strengthen or lessen the suspicion of a particular diagnosis, based on the color of fluorescence of the affected skin being illuminated. In addition, subtle changes in color may be detected as well.