Since the dawn of time, the medicinal properties of light have been recognized and utilized for healing. Ancient Egyptians constructed solariums fitted with colored glass to harness specific colors of the visible spectrum to heal disease. It was the Egyptians who first recognize that if you color glass it will filter out all of the other wavelengths of the visible spectrum of light and give you a pure form of red light, which is 600-700 nanometer wavelength radiation. Early use by the Greeks and Romans emphasized the thermal effects of light.
In 1903, Neils Ryberg Finsen was awarded the Nobel Prize in medicine for successfully using ultraviolet light to successfully treat people with Tuberculosis. Today Finsen is recognized as the father of modern phototherapy.
I want to show you a brochure I found. It’s from the early 1900s and on the front it reads ‘Enjoy the sun indoors with the homesun.’ It’s a British made product called the Vi-Tan ultraviolet home unit and it’s essentially an ultraviolet incandescent light bath box. It has an incandescent bulb, a mercury vapor lamp, which emits light in the ultraviolet spectrum, which will of course provide vitamin D.