A viewing angle diffusion film and a display panel are disclosed. The viewing angle diffusion film includes a substrate and a refractive protrusion disposed on a surface of the substrate. The refractive protrusion includes a first side surface away from a center of the substrate, and the first side surface includes a first curved surface.

An external light use type display body including: a light diffusion control layer; a display layer; and a reflective layer. The light diffusion control layer has a regular internal structure that comprises a plurality of regions having a relatively high refractive index in a region having a relatively low refractive index. The reflective layer has a patterned indented structure when at least one cross section cut in a thickness direction is viewed. When the entrance plane is irradiated with light rays that travel on the light ray traveling plane with a predetermined incident angle while being scanned along an intersection line of the light ray traveling plane and the entrance plane, the ratio of the light rays satisfying the following Formula (1) or Formula (2) is 50% or more.

θ.sub.id<θ.sub.dd−≤θ.sub.od≤θ.sub.dd+  (1)

θ.sub.dd−≤θ.sub.id≤θ.sub.dd+<θ.sub.od  (2)

A light-diffusing layer is provided for diffusing incident light by diffracting at least a portion of the incident light, and the diffuse light diffused by the light-diffusing layer is diffused about a direction different from the emission direction of non-diffused light that passes through the light-diffusing layer without being diffused.

In the case where a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer having a refractive index adjustment zone is provided in such a manner that two PET separators are laminated to opposite surfaces of the pressure-sensitive adhesive layer, it is difficult to distinguish between obverse and reverse sides of the pressure-sensitive adhesive sheet itself. The present invention is directed to solving the above problems and, specifically, to offering a pressure-sensitive adhesive sheet having a refractive index adjustment zone capable of being easily produced at low cost, in a state in which it is preliminarily laminated with a substrate provided with an electroconductive layer, thereby making it possible to resolve complexity in handling (to easily distinguish between one surface defined by the refractive index adjustment zone and the other surface defined by the remaining zone).

There is provided a light source unit including a semiconductor light emitting device, and a rotary mirror device having a mirror surface on a first side, and a second side to which a rotational shaft of a motor is connected, wherein the mirror surface has an undulating section shape of convex and concave shape portions, wherein the rotary mirror device is disposed so as to reflect light emitted from the semiconductor light emitting device on the mirror surface.

An optical structure includes a high refractive-index layer and a low refractive-index layer laminated on the high refractive-index layer and having a refractive index lower than that of the high refractive-index layer, and is disposed on a display surface of a display device. An interface between the layers has a concave-and-convex shape, and each of a concavity and a convexity in the shape has a flat portion extending in a surface direction of the layers. A side surface of the concave-and-convex shape, which extends between the flat portions of the concavity and convexity, is a curved surface or a folded surface that is convex to the low refractive-index layer. A difference between a maximum angle and a minimum angle, which are defined between the side surface of the concave-and-convex shape and a normal direction of the layers, is not less than 3 degrees and not more than 60 degrees.

A transparent screen includes a substrate capable of transmitting light; and a plurality of dots formed on a surface of the substrate, each of the dots having wavelength-selective reflectivity and being formed of a liquid crystal material having a cholesteric structure, in which the cholesteric structure gives a striped pattern of bright parts and dark parts in a cross-sectional view of the dot observed by scanning electron microscope, the dot includes a portion having a height that increases continuously to the maximum height in a direction extending from the edge toward the center of the dot, and in the portion, the angle formed by the normal line to a line that is formed by a first one of the dark parts as counted from the surface of the dot on the opposite side of the substrate and the surface of the dot is in the range of 70° to 90°.

A polarizing plate and a liquid crystal display including the same are provided. A polarizing plate includes a polarizing film and a contrast-improving optical film sequentially stacked in the stated order. The contrast-improving optical film includes a contrast-improving layer including a first resin layer and a second resin layer facing the first resin layer. The second resin layer includes a patterned portion having optical patterns and a flat section between the optical patterns. The second resin layer satisfies Equation 1, and the polarizing plate has a contrast ratio gain of about 1.00 or more, as represented by Equation 2.

A prism sheet includes a sheet body that includes opposite light exiting and incident surfaces, and a lateral side transversely connected between the light incident and exiting surfaces. The light exiting surface includes two side regions disposed on two opposite sides of a reference line on the light exiting surface, which is perpendicular to the lateral side. The sheet body further includes a plurality of parallel microstructure members protruding from the light exiting surface and extending perpendicularly to the lateral side. The microstructure members have a distribution density decreased in a density-decreasing direction parallel to the lateral side and pointing toward either of the side regions from the reference line.

This light-emitting device has a light-emitting element, whereof the shape in planar view is rectangular, for emitting light, and a light flux control member. The light flux control member has an entry surface, a back surface, and where grid-shaped protruding stripes comprising a plurality of protruding stripes disposed into a grid shape or grid-shaped recessed stripes comprising a plurality of recessed stripes disposed into a grid shape are formed; and an exit surface disposed on the surface facing away from the back surface, and where the light that has entered the entry surface is caused to exit. Of the angles formed by each of the four sides constituting the outer edges of the light-emitting element and a first virtual straight line that is parallel to the crest lines of the grid-shaped protruding stripes or the valley lines of the grid-shaped recessed stripes, the smaller angle is an acute angle.