Abstract: In a display device in which a display panel is supported from the back by a back frame, the back frame is composed of a pair of long side portions and a pair of short side portions each having an angular structure in section. Whereby, torsional strength is increased while suppressing increase in weight. This leads to increase in torsional strength while suppressing increase in weight even in a large-sized display screen.

Abstract: In a surface light source device including: a light source section having a light emitting face; an optical panel arranged so as to cover the light emitting face; and a at least one frame having a front face portion that covers the peripheral portion of the light emitting face, the at least one frame is composed of a plurality of divisional members connected with each other and a light shielding portion is provided at each slit between the divisional members in the front face portion of the at least one frame. Whereby, light from the light source section is prevented from leaking through each slit between the divisional members in the front face portion of the at least one frame.

Abstract: In a surface light source device including: a light source section having a light emitting face; an optical panel arranged so as to cover the light emitting face; and a at least one frame having a front face portion that covers the peripheral portion of the light emitting face, the at least one frame is composed of a plurality of divisional members connected with each other and a light shielding portion is provided at each slit between the divisional members in the front face portion of the at least one frame. Whereby, light from the light source section is prevented from leaking through each slit between the divisional members in the front face portion of the at least one frame.

Abstract: In a display device in which a display panel is supported from the back by a back frame, the back frame is composed of a pair of long side portions and a pair of short side portions each having an angular structure in section. Whereby, torsional strength is increased while suppressing increase in weight. This leads to increase in torsional strength while suppressing increase in weight even in a large-sized display screen.

Abstract: A high-tenacity water-soluble polyvinyl alcohol fiber comprising a fiber composed of a polyvinyl alcohol polymer with a degree of polymerization of at least 1500 and a degree of saponification of 80 to 99 mol % and having a tensile strength of at least 10 g/d, an initial modulus of at least 100 g/d, and a water soluble temperature of 100.degree. C. or below, and a process of producing the fiber.

Abstract: An ultra-high-tenacity multifilament fiber of polyvinyl alcohol having a degree of polymerization of at least 1500, said filament having a tensile strength of at least 12 g/d and an initial modulus greater than 280 g/d, which is produced by a process for producing an ultra-high-tenacity polyvinyl alcohol fiber which comprises the steps of dissolving polyvinyl alcohol having a degree of polymerization of at least 1500 in a solvent, dry-spinning the resulting polymer solution through a spinneret into an environment of air or inert gas, introducing the dry-spun filaments into a coagulating bath, and drawing the coagulated filaments at a total effective draw ratio of at least 20 times.

Abstract: An ultra-high-tenacity multifilament fiber of polyvinyl alcohol having a degree of polymerization of at least 1500, said filament having a tensile strength of at least 12 g/d and an initial modulus greater than 280 g/d, which is produced by a process for producing an ultra-high-tenacity polyvinyl alcohol fiber which comprises the steps of dissolving polyvinyl alcohol having a degree of polymerization of at least 1500 in a solvent, dry-spinning the resulting polymer solution through a spinneret into an environment of air or inert gas, introducing the dry-spun filaments into a coagulating bath, and drawing the coagulated filaments at a total effective draw ratio of at least 20 times.

Abstract: In a surface light source device including: a light source section having a light emitting face; an optical panel arranged so as to cover the light emitting face; and a at least one frame having a front face portion that covers the peripheral portion of the light emitting face, the at least one frame is composed of a plurality of divisional members connected with each other and a light shielding portion is provided at each slit between the divisional members in the front face portion of the at least one frame. Whereby, light from the light source section is prevented from leaking through each slit between the divisional members in the front face portion of the at least one frame.