Abstract: A liquid-crystal display device comprises; a display panel having a matrix array of pixel dots in red, green or blue color; a surface illuminant device that has white-light LEDs as light sources; one or more driver ICs, each of which includes three converter circuits respectively for the red, the green and the blue and performs a conversion to signal voltages from image data signals according to a respective conversion curve; and a nonvolatile memory in which data determining the conversion curves are stored after the data are attuned to variation in chromaticity of the white-light LEDs in the surface illuminant device so that said variation is compensated based on measurement of the chromaticity of each of the white-light LEDs.

Abstract: A valve assembly which includes a valve body made of a hard synthetic resin, preferably PVC or PVDF. The valve body is formed with a fluid passage laterally extending therethrough, and having no flanges for connection with neighboring pipings. There is a valve member for the cooperation with the valve body, the valve member has nearly a true cylindrical outer configuration, having a taper of 1/30-1/10. A shallow concave groove or recess is formed in the bottom wall surface of the valve member kept in fluid communication with the axial bore formed in the latter. The material of the valve member is selected to be softer than that of the valve body for securing benefit for aquiring better wearing characteristics in cooperation with the valve seats. This material is preferably polypropylene. The working surface of the valve member has a generally convex-cured configuration and the valve seat of the valve body has a concave configuration mating therewith.

Abstract: A butterfly valve resistant to corrosive gases. The valve body carries a valve seat ring having an elastic layer and an inner lining layer composed of polyvinylidene difluoride. The moisture permeability of the elastic layer is higher than that of the lining layer. On the outer surface of the valve seat ring facing the valve body, annular grooves are formed. Through the wall of the valve body, there are formed vents for moisture. These annular grooves and vents for moisture are communicated with each other. When the moisture contained in corrosive gases permeates through the lining and elastic layers, such moisture will easily be drained through the vents. Thereby, moisture permeated through the valve seat ring will not accumulate between the valve seat ring and the valve body. This prevents deformation of the valve seat ring, and extends valve use.

Abstract: The invention relates to a butterfly valve assembly having a stationary valve body formed with an axial fluid flow passage opening and a turnable valve member adapted for full opening, partial opening and full closing of the said passage opening. There is provided further a valve seat ring composed of an inner protecting layer of fluoride containing resin and an outer back-up layer of rubber or its equivalent. According to this invention, at least two parallel ring grooves are provided on the radially outwardly directing surface of the said elastomer layer which has a substantially channel-shaped cross-section embracing a substantial part of the valve body when the valve seat ring is attached in position to the valve body.

Abstract: In a ball valve made of a plastic material and having, as the principal components thereof, a valve body 1, a ball 2, carriers 3 contacting with said ball and connecting with body caps 4, a valve seat 6, a stem 8 and a handle 7 attached to said stem, an improvement is disclosed which comprises providing the carrier 3 disposed on each side of said ball with a flange 13 and interposing an elastic seat gasket 12 between the valve body 1 and the flange 13 of each carrier 3.