Abstract: Blue-colored, infrared radiation absorbing glass compositions are prepared by the addition of zinc sulfide and zinc oxide to glass compositions containing iron. The zinc sulfide acts as a reducing agent, to maintain a portion of the iron in the ferrous state, and the zinc oxide prevents amber coloration of the glass which would otherwise occur due to the addition of the zinc sulfide to the glass batch.

Abstract: Optical light filters, useful for eye protection from laser radiation, are provided. The filter can absorb harmful radiation from lasers of several (at least six (6)) types which have a range of different specific wavelengths, yet permit sufficient visibility. A novel mixture of compatible absorbers in a transparent plastic carrier, having the required stability to withstand processing conditions and having satisfactory stability for use under environmental conditions is disclosed.

Abstract: An infrared absorbent comprising .alpha.-diimine metal complex is disclosed. With the use of the infrared absorbent, there is provided an infrared absorbing material capable of absorbing a near-infrared light having a wavelength of 700-1500 nm and a far-infrared light. The infrared absorbent has a good fastness to heat and light. The infrared absorbing material is suitable for an optical filter and optical information recording medium.

Abstract: An infrared absorbent comprising a metal complex compound prepared by coordinating two thiorato bidentate ligands to a center metal and neutralizing a complex ion with a cation. With use of the infrared absorbent, there is provided an infrared absorbing material capable of absorbing a far-infrared or near-infrared light having a wavelength of 700-1500 nm which has a high transmittance of a visible light and a good fastness to heat and light. The infrared absorbing material can be used for an infrared absorbing material such as an optical filter or other various objects.

Abstract: A device for the qualitative measurement of uv radiation received by the skin consists of a laminar strip for application to the skin, the strip including a photochromic material disposed intermediate the ends of the strip and a reference material also disposed intermediate the ends of the strip. The reference material is suitably a dye which matches closely the color of the photochromic material after exposure to a pre-determined quantity of uv radiation. The predetermined quantity of uv radiation corresponds to the maximum exposure tolerable by the particular skin type. The device enables one to visually assess exposure to uv radiation by a direct comparison of the color densities of the photochromic material and the reference material during exposure to sunlight.

Abstract: Polyol(allyl carbonate) monomer, e.g., diethylene glycol bis(allyl carbonate), containing 1,4-dihydroxy anthraquinone in amounts sufficient to selectively absorb at least 94 percent of the visible and ultraviolet light segments of the electromagnetic spectrum below 530 nanometers is described. Also described are ophthalmic articles prepared by curing the monomer.

Abstract: The solar blind ultraviolet filter includes in an intimate cascade relationship an ultraviolet grade quartz cell containing chlorine gas receiving light energy on an input face thereof, a first Jena UG5 glass cell containing potassium iodide doped with thallium, a second Jena UG5 glass cell containing a 2, 3-dihydro-5, 7-dimethyl-1H-1, 4-diazepine perchlorate and glycerol solution and a Jena UG5 glass and ultraviolet grade quartz cell containing nickel sulfate hexahydrate as the output element of the filter. A black anodized aluminum shell encloses the peripheral surface of all of the above cells. An extremely high viscosity interface coupling medium, such as dimethyl polysiloxane, is disposed at all interface surfaces of the various materials employed in the filter to minimize reflection losses at these interface surfaces.