Abstract: A post objective type optical scanner for having a light source for emitting a light beam having a first width in the scanning direction and a second width in the sub-scanning direction, a single lens having an incident surface and an emergent surface and including a scanning optical system having a first light source side principal point, and a sub-scanning optical system having a second light source side principal point, for converting a light beam emitted from the light source having a scanningwise width and a subscanningwise width, the scanning optical system converting the first width of the light beam into the scanningwise of the scanning beam while the sub-scanning optical system converting the second width of the light beam into the subscanningwise width of the scanning beam. The distance of the first light source side principal point from the light source is greater than the distance of the second light source side principal point from the light source.

Abstract: A highly crystalline polypropylene for forming film which is obtained by subjecting to the molecular weight degradation a propylene homopolymer obtained by the polymerization of propylene over a stereoregulating catalyst and which has:(a) a melt flow rate, MFR, in the range of 1 to 10 min determined in accordance with ASTM-D-1238;(b) a ratio Q which is the ratio of weight average molecular weight M.sub.W to the number average molecular weight M.sub.N, namely, M.sub.W /M.sub.N, in the range of 2.5 to 4.0;(c) a density of at least 0.9070 g/cm.sup.3 or more;(d) the cold xylene soluble matter (CXS) in the range of 2.5% by weight at the highest.The highly crystalline polypropylene will produce film endowed with good transparency, stiffness, impact strength and resistance to blocking, in improved cost performance, which could to some extent be antagonistic to each other.

Abstract: A post-objective type optical scanner in which optical flux is converted to condensed light or diffused light by a lens and then scanned on a scanning surface by an optical deflector is constituted by a light source, an optical scanner for leading the flux of light from the light source to an optical deflector and an optical deflector which has a toric deflecting surface in which the radius in the scanning direction is convex and the radius in the sub-scanning direction is concave, and which compensates the curvatures of field in both scanning and sub-scanning directions and scans the optical flux by rotation.

Abstract: A projection lens for projecting images displayed on an image display device having angle-of-view dependency has high image focusing characteristics corresponding to high definition images, wide field angle, and telecentric characteristics. In addition, a projection television system using the same can be minimized in its size.

Abstract: A high-resolution post-objective type optical scanner in which a beam of light is scanned by an optical deflector onto a scanning surface after it is converged by a condensing lens, the light beam converged on the scanning surface having a spot size with an intensity of 1/e.sup.2 and not exceeding 80 .mu.m over the entire area of the scanning surface. The optical deflector includes a reflecting surface composed of a cylindrical surface or a spherical surface. A compensating lens disposed between the optical deflector and the scanning surface has a power which varies in the scanning direction between a central portion and a peripheral portion of the compensating lens. The distance r between an axis of rotation of the optical deflector and a deflecting point, the distance L between the deflecting point and the scanning surface, and an effective scanning width Y.sub.O are related by the relationship r.gtoreq.-0.025.times.L+0.1.times.Y.sub.o +1.4.

Abstract: A screen is made having the same characteristics as of a known lenticular lens by having a number of organic materials provided in scatter arrangement within a substrate of a screen and shaped into bar-like configuration by stretching for the purpose of anisotropic diffusion of light.

Abstract: A projection lens for projecting onto a screen an enlargement of an image appearing on a CRT wherein comma and chromatic aberration, which degrades imaging quality, can be properly corrected comprises 4 lens units. The projection lens comprises, in the order from the screen end, a first lens unit of positive optical power having a strong convex surface facing the screen end, a second lens unit comprising a biconvex lens element of positive optical power and a lens element of negative optical power having a concave surface facing the screen end, a third lens unit of positive optical power at an optical axis having a convex surface facing the screen end, and a fourth lens unit of negative optical power having a concave surface facing the screen end.

Abstract: An optical system for a laser beam printer uses, as a first image forming system, an anamorphic lens whose first surface facing a light source has a refraction power rotation-symmetrical with respect to the optical axis, and whose second surface is a toric surface having refraction powers different in horizontal and vertical directions. A coupling optical system for an optical disk information recording apparatus comprises an anamorphic single lens whose first surface is a toric surface correcting aberration only in a first direction in which radiation angle of a light beam emitted from a light source is larger than that in a second direction perpendicular to the first direction, and whose second surface is a toric surface correctly aberration only in the second direction.

Abstract: A light scanning system uses a tilting angle error correcting system, applying a conjugate relation from geometrical optics. A light beam from a light source is converged to a linear image near a deflecting surface of a deflector by a first converging optical system. The deflected light beam from the deflecting surface is converged to a light spot on a scanning plane by a second converging optical system. The first converging optical system provides the light converging effect only in a plane perpendicular to the direction of scan and also has an overcorrected spherical aberration, so that the spherical aberration of the entire system can be favorably corrected, thereby making it possible to obtain a high converging performance for realizing high resolution.

Abstract: A selective shading device has a number of shading plates or planar members and a supporting body that holds the plates or planar members in such a manner that they are arrranged radially with respect to an optical axis. The device blocks sagittal bundles of rays. A preferred example of the supporting body is a cylindrical frame that holds the shading plates perpendicularly to the inner surface thereof. Alternatively, the shading planar members are formed within a lens element along the edge thereof.

Abstract: A high definition projection lens for projecting on a screen an enlargement of an image appearing on a high resolution CRT is disclosed. The projection lens comprises a first lens having a positive optical power and a convex surface facing the screen, a meniscus second lens having a positive optical power, a third lens having bi-concave surfaces and a negative optical power, a fourth lens having a positive optical power, a fifth lens having bi-convex surfaces and a positive optical power, and a sixth lens having a negative power and an aspheric concave surface facing the fifth lens.

Abstract: A projection lens for projecting an image appearing on a cathode-ray tube onto a screen, small in residual aberrations, having a high imaging performance, also having a large aperture ratio and a wide field angle, suitable for a video projector having a high definition of, say, 1,125 scanning lines. The projection lens has, successively from the screen side, a Gauss type lens system, a positive lens mainly for enlarging the aperture ratio, and a negative lens mainly for widening the field angle, which negative lens has a strongly concave surface at the screen end.

Abstract: A color corrected projection lens with a large aperture ratio and a wide angle of view for producing on a screen an enlargement of an image appearing on a CRT, the lens having sequentially from the screen end a first unit of a bi-convex element having a positive power with a strongly convex surface directed toward the screen end, a second unit of a bi-concave element having a negative power and being located at or in the vicinity of the entrance pupil position of the entire lens system, a third unit of a bi-convex element having a positive power, and a fourth unit having a negative power with a strongly concave surface directed toward the screen end.

Abstract: A projection lens having a large aperture ratio has 3 units for projecting an enlargemen of an image appearing on a CRT onto a screen. The first unit from the screen has a negative power so that the entrance pupil is moved toward the screen to thereby improve off-axis vignetting factor. The second unit consists of two positive power lens elements so that the positive power of the entire system is shared by the second unit and the temperature characteristic is improved by using a positive power glass lens element as one of the two positive power lens elements. The third unit has a negative power to correct curvature of field.

Abstract: A compact projection lens for projecting an enlargement of an image appearing on a cathode ray tube (CRT) onto the screen. The projection lens has a first lens having a positive optical power and at least one aspheric surface, surface of the first lens that faces the screen being convex, a second lens having bi-convex surfaces and a positive optical power, and a third lens having a negative optical power and an aspheric concave surface facing the second lens. The focal length f.sub.1 of the first lens and the focal length f.sub.2 of the second lens are selected for satisfying a condition of0.55<f.sub.1 /f.sub.2 <1.2.

Abstract: A projection lens system for a projection television for projecting on a screen an enlargement of an image displayed on a cathode ray tube includes a first bi-aspherical lens of positive power, the surface of which is toward the end of the lens system which is to face the screen being a convex surface having a larger curvature than the other surface thereof, a second double convex lens of glass, and a third bi-aspherical lens of negative power, the surface of which is toward the screen end being a concave surface having a larger curvature than the other surface thereof, the first, second and third lens being disposed in the order from the screen end, and satisfying the conditions: 1.3f<f.sub.1 <1.9f; 0.9f<f.sub.2 <1.2f; 0.25f<d.sub.4 <0.35f; r.sub.1 <.vertline.r.sub.2 .vertline.; and 0.4<r.sub.3 /.vertline.r.sub.4 .vertline.<0.75, where f is the total focal length, f.sub.1 and f.sub.2 are the respective focal lengths of the first and second lenses, d.sub.

Abstract: A projection lens apparatus for projecting an image from a CRT onto a remote screen. The lens apparatus is basically a Petzval type for a large aperture ratio and comprises three lenses. The first lens is a plastic lens having at least one aspherical surface and the third lens has a bi-aspherical surface. To reduce the thermal drift of the focal position, the second lens is a glass lens, having relatively largely positive optical power.

Abstract: A plastic laminated metallic foil is prepared by laminating a first layer of a polymer selected from the group consisting of ethylene-unsaturated carboxylic acid copolymers, ethylene-unsaturated carboxylic acid ester copolymers, ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid-ester ternary copolymers, ionomers containing these copolymers as the base, and graft copolymers of polyethylene and unsaturated carboxylic acids on at least one surface of a metallic foil, and further laminating a second layer of a polymer selected from the group consisting of polyethylene, ethylene-vinyl acetate copolymers, ethylene-unsaturated carboxylic acid ester copolymers, and graft copolymers of polyethylene and unsaturated carboxylic acid esters onto the first polymer layer of the metallic foil.

Abstract: A plastic laminated metallic foil is prepared by laminating a first layer of a polymer selected from the group consisting of ethylene-unsaturated carboxylic acid copolymers, ethylene-unsaturated carboxylic acid ester copolymers, ethylene-unsaturated carboxylic acid-unsaturated carboxylic acid-ester ternary copolymers, ionomers containing these copolymers as the base, and graft copolymers of polyethylene and unsaturated carboxylic acids on at least one surface of a metallic foil, and further laminating a second layer of a polymer selected from the group consisting of polyethylene, ethylene-vinyl acetate copolymers, ethylene-unsaturated carboxylic acid ester copolymers, and graft copolymers of polyethylene and unsaturated carboxylic acid esters onto the first polymer layer of the metallic foil.

Abstract: A metal foil-plastic laminate comprising an upper layer of a member selected from the group consisting of a polyethylene-vinyl acetate and ethylene-vinyl acetate copolymer containing no more than 8 wt. % of vinyl acetate and a lower layer of an ethylene-vinyl acetate copolymer containing 10-45 wt. % of vinyl acetate, thermally pressed on at least one surface of a metal foil, said lower layer being in contact with the metal foil and method for preparing the same.