Abstract: A fluorescent display device comprising at least one phosphor screen composed of a mixture of a SnO.sub.2 :Eu phosphor with at least one of the cathodoluminescent phosphors having emission spectra and exitation properties different from SnO.sub.2 :Eu phosphor. This fluorescent display device emits light of different colors when driven at different voltages and at pulse voltages of different duty cycles. A display apparatus comprises such a fluorescent display device and a driving device with variable output voltage.

Abstract: The present invention is an electrical terminal unit adapted for supporting an electrical circuit element, for example, a moisture responsive resistor or the like and a sensing device employing this terminal unit. The terminal unit makes the influence of the reduction in insulation resistance between the terminals due to adhesion of pollutants to the terminal unit negligible by providing a grounded electrically conductive member or electrode member between the conductive terminal leads extending through a base or substrate of the terminal unit for electrically separating these terminal leads.

Abstract: There is provided a humidity sensitive ceramic resistor having high humidity activity, low electrical resistance, quick response rate to humidity and high stability with respect to time, temperature, humidity and electric load which is suited for humidity-controlling devices. The ceramic resistor comprises a ceramic composition comprising at least one component having a spinel type cubic symmetry selected from the group consisting of MgCr.sub.2 O.sub.4, FeCr.sub.2 O.sub.4, NiCr.sub.2 O.sub.4, CoCr.sub.2 O.sub.4, MnCr.sub.2 O.sub.4, CuCr.sub.2 O.sub.4, Mg.sub.2 TiO.sub.4, Zn.sub.2 TiO.sub.4, Mg.sub.2 SnO.sub.4 and Zn.sub.2 SnO.sub.4, and , if desired, at least one component selected from the group consisting of TiO.sub.2, ZrO.sub.2, HfO.sub.2 and SnO.sub.2.

Abstract: A humidity sensitive resistor device for sensing the humidity of an ambient atmosphere. The device has a humidity sensitive resistor formed by a metal oxide sintered substrate having electrodes on one surface thereof, the resistivity of the humidity sensitive resistor decreasing as the ambient humidity which can affect the surface of the humidity sensitive resistor increases; and a heater positioned near the humidity sensitive resistor for applying radiant heat to the surface of the humidity sensitive resistor, which heater can be used for improving the sensitivity of the humidity sensitive resistor. By the application of a slight amount of radiant heat, the humidity sensitivity increases, and by the application of a large amount of strong heat, stains which may be on the surface of the humidity sensitive resistor such as oil can be cleaned off so as to recover the sensitivity of the humidity sensitive resistor which might have been deteriorated by the stain.

Abstract: A method of making a polycrystalline sulphide ceramic body by sulphurizing an oxide material in a carbon disulphide atmosphere at a temperature in the range of 400-1000.degree. C and less than the transforming temperature of the sulphide, which transforming temperature represents either the decomposition temperature or the sublimation temperature inherent to the sulphide. One of the advantages of this method is that sulphides can be easily made by the very strong reduction action of carbon disulphide. This application also relates to sulphides made thereby.

Abstract: A method of making a zinc sulphide ceramic body having a low electrical resistance characterized by sulphurizing a starting oxide material consisting essentially of zinc oxide and from 0.01 atomic % to 6.0 atomic % of at least one oxide of a metal selected from the group consisting of aluminum, magnesium, nickel, cobalt, cadmium, lead, indium, bismuth, antimony, titanium, zirconium, silicon, tin, niobium, tantalum, tungsten, and the rare earth element metals in a carbon disulphide atmosphere at a temperature in the range of 700.degree. C to 1000.degree. C. This zinc sulphide ceramic body can be formed into non-linear elements such as phosphors, photoconductors, luminescent elements, varistors, piezoelectric transducers, capacitors and combinations thereof. Particularly, by using this zinc sulphide body in light emitting elements, the luminous efficiency as well as the working voltage can be improved.

Abstract: Humidity sensitive ceramic resistor having a high humidity activity, a low electrical resistance and a high stability with respect to time, temperature, humidity and electric load and suited for use in humidity-controlling devices is provided by a sintered mixture of a main component, which consists essentially of chromium oxide and at least one metal oxide selected from the group consisting of TiO.sub.2, ZrO.sub.2, HfO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, WO.sub.3, MnO.sub.2, MoO.sub.2, CeO.sub.2, DyO.sub.2, VO.sub.2, SiO.sub.2 and GeO.sub.2, and an addition of at least one metal oxide selected from the group consisting of BeO, MgO, CaO, SrO, BaO, FeO, NiO, CuO, ZnO, CdO and PbO. Furthermore, humidity sensitive thin layer ceramic resistor having an improved quick response to humidity is obtained by sintering a mixture having the above composition with a glass frit binder.