Abstract: A semiconductor laser screen in a cathode-ray tube with a sealed casing. The laser screen has a screen structure which is formed by a semiconductor member, a reflecting mirror and a partly transparent mirror on opposite sides of the semiconductor member. The screen structure is connected to a transparent support by means of a connecting layer which is formed by glass having a softening point of at least 675K. The materials of the semiconductor member, the transparent support, the connecting layer and the casing are made of materials with similarly low coefficients of expansion to prevent damage to the screen as it cools down from the manufacturing process.

Abstract: A heat removing support member connected to an output mirror of an optical cavity of a cathode-ray tube has microscopic roughness of its surface facing towards the screen.

Abstract: A laser screen of a cathode-ray tube has a semiconductor member made of a semiconductor material selected from the group consisting of an A.sup.II B.sup.VI compound or a solid solution of an A.sup.II B.sup.VI compound and a pair of mirror layers formed on the opposite sides of said semiconductor member. The material of the semiconductor member is doped with a donor impurity in the form of an element of the VII Group of the Periodic Table. A content of the donor impurity ranges from 3.multidot.10.sup.17 to 5.multidot.10.sup.18 cm.sup.-3, and the resistivity of the semiconductor member is maximum 10.sup.-1 .OMEGA./cm.

Abstract: In a laser screen for a cathode-ray tube having a semiconductor member of a semiconductor compound positioned between a partly transparent mirror and a reflecting mirror, an intermediate member is grown by deposition from vapor phase on the partly transparent mirror. The intermediate member is made of a semiconductor material transparent for radiation generated by the screen and has a bandgap width which is at least 0.98 times as great as the bandgap width of the material of the semiconductor member. The intermediate member is cemented to a transparent heat removing support member.

Abstract: A semiconductor member of a laser screen cathode-ray tube is made of a semiconductor compound selected from the group consisting of binary, three-component and four-component compounds of elements of the second and sixth Groups of the Periodic System and a support member is made of a semiconductor compound of the same type with a bandgap width such as to make it transparent for radiation generated by said screen. Maximum of 15% of atoms of the overgrown support member are substituted for isovalent atoms and the bandgap width of the support member is at least 0.1 eV greater than the bandgap width of the semiconductor member. The support member is overgrown from vapor phase on a partly transparent mirror deposited to one side of the semiconductor member forming an optical cavity with a reflecting mirror deposited to the opposite side of the semiconductor member.

Abstract: An electron beam current modulator is provided between a cathode and a laser screen of a cathode-ray tube and has at least three deflecting plates positioned around, and symmetrically with respect to an optical axis of the cathode-ray tube and a diaphragm having an aperture of a regular shape. An electromagnetic control system is provided between the cathode and deflecting plates. A pickup senses position of the electron beam and produces a signal in case of an offset of the electron beam with respect to the optical axis. A video signal source is connected to a carrier generator having an output connected to an input of a phase shifter. The phase shifter has its outputs connected to the deflecting plates to rotate the cross-section of the electron beam in a plane drawn perpendicularly with respect to the optical axis. The apparatus has a control unit having an input connected to the pickup and an output connected to the electromagnetic control system.