One of the most promising technologies of the 21st century is LED lighting, which today is widely used in various fields, ranging from indicators of the operation of electrical appliances, screen lights to street, industrial and residential lighting. LED lighting significantly saves energy and budget, quickly returning your investment, helping to solve problems for both individual users and large businesses. However, "each medal has two sides," one of which, as a rule, is "dark." Is this the case with LED lighting?