Abstract: Apparatus for use in sunbathing comprises a screen formed of a sheet of thermoplastic or fiber material which is transparent to the safe UV-A wavelengths of solar radiation and the visible light range between 400-450 nm but which contains uniformly distributed therethrough a first agent which absorbs at least 80% of the UV-B radiation in the 310-320 nm range and all radiation below 310 nm, and a second agent and third agent which prevent transmission therethrough of some radiations above 450 nm wavelength, i.e. visible light and infra-red. The second agent may be an absorbing dye or pigment. The third agent may be finely divided carbon or ground glass. The screen may be mounted on a frame or fabricated into clothing so as to shield the sunbather from the acutely and chronically harmful wavelengths of radiation, to prevent unpleasant overheating, and to provide subdued lighting.

Abstract: Method and apparatus for encouraging maximal plant growth which method and apparatus comprise a light filter which prevents the natural decay of plant growth stimulating materials by absorption of UV radiation while permitting photosynthesis to occur with blue light in the absence of attendant heat generating and dehydrating radiations caused by green, yellow and infra-red light. The objective is made possible according to the preferred embodiment of the invention by interposing separately, continuously, or discontinuously, a combination of filters made of solid material between the sun and the growing plants which block out radiation in those wave lengths which are either physiologically harmful or which retard growth, but do not inhibit those wavelengths which are necessary for photosynthesis, metabolism, differentiation and development.

Abstract: Apparatus for use in sunbathing comprises a screen formed of a sheet of thermoplastic or fiber material which is transparent to the safe UV-A wavelengths of solar radiation and the visible light range between 400-450 nm but which contains uniformly distributed therethrough a first agent which absorbs at least 80% of the UV-B radiation in the 310--320 nm range and all radiation below 310 nm, and a second agent and third agent which prevent transmission therethrough of some radiations above 450 nm wavelength, i.e. visible light and infra-red. The second agent may be an absorbing dye or pigment. The third agent may be finely divided carbon or ground glass. The screen may be mounted on a frame or fabricated into clothing so as to shield the sunbather from the acutely and chronically harmful wavelengths of radiation, to prevent unpleasant overheating, and to provide subdued lighting.