Abstract: A visual has a multilayer ceramic substrate (1) with an emission layer (2) on its front face. The substrate is mounted on carrier (4) with a L-shaped cross-section, via the foot (41) of the L. A glass face plate (5) is on the top of the main limb (42) of the L. The face plate has a phosphor layer (6) on its inside surface. A succession (7) of vias and interconnects in the L provides connection from the substrate (1) to the phosphor layer. A band (8) of frit is screen printed onto the inside of the face plate, peripherally of phosphor layer. In a corresponding position on the top of the main limb, a groove (9) is formed. On assembly of the face plate to the carrier, the frit (8) fits into the groove (9). The face plate abuts the top of the limb (42), thereby defining the separation of the face plate and the emission substrate.

Abstract: A visual has a multilayer ceramic substrate 1 with an emission layer 2 on its front face. The substrate is mounted on carrier 4 with a L-shaped cross-section, via the foot 41 of the L. A glass face plate 5 is on the top of the main limb 42 of the L. The face plate has a phosphor layer 6 on its inside surface. A succession 7 of vias and interconnects in the L provides connection from the substrate 1 to the phosphor layer. A band 8 of frit is screen printed onto the inside of the face plate, peripherally of phosphor layer. In a corresponding position on the top of the main limb, a groove 9 is formed. The groove extends around the full extent of the carrier. On assembly of the face plate to the carrier, the frit 8 fits into the groove 9. The face plate abuts the top of the limb 42, thereby defining the separation of the face plate and the emission substrate.

Abstract: A double glazing unit has a pair of glass sheets 1, 2, with a frit seal 3 therebetween, the frit seal being fused to both sheets and extending around the periphery of the unit. The frit seal is fused by irradiation with light 4 from a laser. Typically, the frit is of brown glass, whereby it readily absorbs heat on laser irradiation.

Abstract: The front layer 1 shown in FIG. 1 is being tape cast in the direction of the arrow A from alumina ceramic material 2 onto a mylar layer 3. The doctor blade 4, which regulates the thickness T of the ceramic layer has serrations 5, which form parallel grooves 6 in the front surface 7 of the layer. After the material has set, by evaporation of the moisture allows the material to be sufficiently fluid for its casting, vias apertures 8 are punched in it, whilst it is still supported on the mylar, FIG. 2. They are filled with via material 9, FIG. 3, as described in more detail below. After via filling, the mylar layer is peeled from the tape cast ceramic.

Abstract: A getter (50) situated in a cavity of a hollow structure (40-46), such as a flat-panel device, is activated by directing light energy locally through part of a hollow structure and onto the getter. The light energy is typically provided by a laser beam (60). The getter, typically of the non-evaporable type, is usually inserted as a single piece of gettering material into the cavity. The getter normally can be activated/re-activated multiple times in this manner, typically during the sealing of different parts of the structure together.

Abstract: A structure, such as a flat-panel device, is sealed together by a gap-jumping technique in which an edge (44S) of a wall (44) is positioned near a matching sealing area (40S) of a plate structure (40) such that a gap (48) at least partially separates the edge of the wall from the sealing area of the plate structure. The gap usually has an average height of 25 .mu.m or more. Energy is then transferred locally to material of the wall along the gap to cause material of the wall and the plate structure to bridge the gap and seal the plate structure to the wall. The energy-transferring step is typically performed with light energy provided by a laser (56). Local energy transfer can also be utilized to tack the plate structure to the wall at multiple spaced-apart locations (44A) along the wall. The tacking operation is typically performed as a preliminary step to sealing the plate structure to the wall.

Abstract: An optical communications system comprises a transceiver arranged to provide two-way communication over an optical communications channel (3). The transceiver comprises a semiconductor light source (4) and a detector (5). The semiconductor light source (4) provides optical signals for transmission via the optical communications channel (3), and the detector (5) detects optical signals received via the optical communications channel and converts said optical signals into electrical signals. Means (2)a, (2)b) are provided for modulating the output of the semiconductor light source (4) with an RF carrier having a first frequency. Said electrical signals are passed through filter (8) adapted to filter out signals at said first frequency.