Bring the Sunlight into your Home! Did you know Vitamin D is the single most underrated nutrient in the world of nutrition? Intended for individuals who may not be able to receive needed sunlight exposure the Sperti Vitamin D Sunlamp uses UVB fluorescent bulbs that emit a proper balance of UVB rays onto your skin naturally generating Vitamin D in the body. The most powerful in-home Phototherapy Lamp on the market the Sperti Vitamin D Sunlamp allows you to experience UVB light therapy from the comfort of your own home.