A magnetic pigment flake includes a filtering film layer, with magnetic or magnetizable material, and a metal nanoparticles layer, formed on a surface of the filtering film layer. The metal nanoparticles layer is configured to generate scattered light enhanced by a local surface plasmon resonance under an irradiation of visible light exceeding a predetermined intensity. An optically variable ink includes an ink body and the above-mentioned magnetic pigment flakes. An anti-falsification article includes an article body and the above-mentioned optically variable ink. The magnetic pigment flake of the optically variable ink is magnetically oriented, such that a bright and dark areas are generated with a viewing angel changing under an irradiation of visible light below the predetermined intensity. Under an irradiation of visible light exceeding the predetermined intensity, light with a color different from that of the bright area is generated on a corresponding position of the dark area.

As described above, one or more aspects of the present disclosure provide articles having structural color, and methods of making articles having structural color.

A resin reflective film, which containing two or more kinds of regions having different refractive indexes from each other, in which a film thickness of the resin film 20 to 5,000 .Math.m, and a total reflectance is 60% or more and a diffuse reflectance is 60% or more for deep ultraviolet rays having a wavelength of 220 to 300 nm.

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)

The present invention relates to a visibility improving film for a display panel and a display device including the same. More specifically, the present invention relates to a visibility improving film for a display panel capable of enhancing the visibility of a laser pointer and exhibiting excellent physical and optical properties, particularly preventing a specular reflection phenomenon of a laser pointer light, by including fine metal particles and inorganic oxide fine particles dispersed in a photocurable resin layer.

According to some embodiments, a transparent screen includes a first transparent substrate having a first transparent substrate index of refraction and including a surface relief pattern, a partially reflective coating formed on the surface relief pattern, and a second transparent substrate bonded over the partially reflective coating with an optical adhesive having the first transparent substrate index of refraction.

An optical device is provided which does not need a collimate lens, and which has a high available efficiency of light. The optical device includes a light source unit 1 emitting light with a wavelength λ, and an optical element 2 with a concavo-convex structure including periodical lenses. When n is a natural number equal to or greater than 1, and the size of a k-th (where k is a natural number equal to or greater than 1) pitch from the smallest one among the pitches of the concavo-convex structure is P.sub.k, a distance L.sub.1 between the light source unit and the optical element satisfies the following formula 1 for equal to or greater than any one pitch P.sub.k.

[00001]$\begin{array}{cc}\frac{\left(n-0.1\right)P_k^2}{2\lambda }\leqq L_1\leqq \frac{\left(n+0.1\right)P_k^2}{2\lambda }& \left(1\right)\end{array}$

A display unit includes a display region and a border region. The display region is configured to include a dark state. A diffusing member is positioned adjacent to the border region such that the diffusing member is coextensive with the border region. A first electromagnetic ray bundle incident on the display region in the dark state produces a first bidirectional reflection distribution function. A second electromagnetic ray bundle incident on the border region produces a second bidirectional reflection distribution function. The diffusing member is configured such that the first bidirectional reflection distribution function is substantially identical to the second bidirectional reflection distribution function. The diffusing member may include a base layer and a surface hologram recorded onto the base layer. The surface hologram is configured to encode a spatial pattern in at least one of the opacity, density, and surface height of the base layer.

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.

To provide a relief structure having a simple structure, capable of being manufactured with ease and at low cost, and capable of improving visibility, and a security medium having the relief structure.

A relief structure includes a grating structure part having a grating formed at a predetermined angle. The grating structure part includes a scattering structure part having a light scattering property.