Abstract: A packaged acoustic wave filter component can include an acoustic wave device including a first piezoelectric layer and an interdigital transducer electrode on the first piezoelectric layer. A support layer may be included over the acoustic wave device, and the packaged hybrid filter component can also include a bulk acoustic wave resonator over the support layer. A cap layer may extend over and encapsulate the bulk acoustic wave resonator. One or more external vias may extend through the support layer and the underlying layers of the acoustic wave device to provide electrical communication with the packaged bulk acoustic wave generator.

Abstract: An optical unit of plastic provided with a surface for incident light and a surface for outgoing light, wherein the surface for incident light is designed to face a light source and the surface for outgoing light is designed to face an element for receiving light so as to optically connect the light source and the element for receiving light and wherein the optical unit is so shaped that light that comes from the light source and is incident on the surface for incident light forms a first image of the light source within the optical unit and a second image of the light source after having gone through the surface for outgoing light and the optical unit is provided with an attenuating portion for attenuating the quantity of light passing therethrough in the vicinity of the position where the first image is formed.

Abstract: An acoustic wave device includes a piezoelectric substrate, interdigital transducer electrodes including a predetermined number of electrode fingers disposed on an upper surface of the substrate, and a dielectric material layer having a first portion and a second portion. The first portion is disposed on the upper surface of the substrate and between the interdigital transducer electrode fingers. The second portion is disposed above the interdigital transducer electrode fingers. The acoustic wave device further includes at least one thermally conductive bridge disposed within the dielectric material layer and contacting upper surfaces of at least two adjacent interdigital transducer electrode fingers to dissipate heat therefrom.

Abstract: An acoustic wave filter component can include a surface acoustic wave device including a first piezoelectric layer, an interdigital transducer electrode on the first piezoelectric layer, and an additional layer, such as a temperature compensation layer, over the interdigital transducer electrode. The acoustic wave filter component can also include a bulk acoustic wave resonator supported by the additional layer. The additional layer may be a layer on which a surface acoustic wave of the surface acoustic wave device will propagate. The bulk acoustic wave resonator may include an air cavity, where a shape of the air cavity is defined in part by the additional layer.

Abstract: A cladding glass for optical fiber comprises 60 to 80% by weight of silicon dioxide (SiO.sub.2), 0.5 to 10% by weight of aluminum oxide (Al.sub.2 O.sub.3), 9 to 17% by weight of an alkali metal oxide, 3 to 15% by weight of boron oxide (B.sub.2 O.sub.3) and more than 0 but not more than 3% by weight of fluorine (F). The cladding glass of this invention can simultaneously satisfy low refractive index and lowered viscosity, and is also excellent in water resistance and weathering resistance.

Abstract: There is provided a multi-component system glass fiber for optical communication which comprises a multi-component system glass for core having a composition comprising SiO.sub.2, BaO, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, at least one alkali metal oxide selected from Na.sub.2 O, K.sub.2 O and Li.sub.2 O, MgO and CaO in amounts as specified in the specification and claims, and a multi-component system glass for clad layer having a composition comprising SiO.sub.2, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, at least one alkaline earth metal selected from MgO and CaO in amounts as specified in the specification and claims. The core in the glass fiber for optical communication according to the present invention shows lower optical loss and the clad layer shows high weathering resistance, and the glass fiber according to the present invention suffers from no devitrification during fiber drawing and is excellent in dimensional stability.

Abstract: An optical fiber which consists of a multicomponent core glass member which is formed of SiO.sub.2, Al.sub.2 O.sub.3 and an alkali metal oxide and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and a multicomponent cladding glass member which is prepared from SiO.sub.2, Al.sub.2 O.sub.3, an alkali metal oxide and at least one component selected from the group consisting of ZnO, ZrO.sub.2 and TiO.sub.2, and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and consequently reduces transmission loss of light and exhibits prominent durability.