A reflective display body includes a light diffusion control layer and a reflective layer. The light diffusion control layer has a plurality of regions having a relatively high refractive index in a region having a relatively low refractive index. The regions having the relatively high refractive index extend from one surface side toward the other surface side of the light diffusion control layer, and a straight line parallel to the extending direction is tilted with respect to the thickness direction of the light diffusion control layer. When a vector C is obtained by projecting a vector, which is parallel to the extending direction and directed from the surface side distal to the display surface of the reflective display body toward the display surface side, onto the display surface, the smallest angle among three angles between vector C and vectors D1 to D3 is more than 0° and 45° or less.

A display device includes an optical assembly and a display that includes a front surface and a back surface. The display is configured to output image light from the front surface and transmit ambient light from the back surface to the front surface. The optical assembly includes a substrate that has a substantially uniform thickness, a beam splitter, and a reflector. The optical assembly is configured to receive the image light output from the front surface of the display and to transmit a portion of the image light at a first non-zero optical power via an optical path that includes reflections at the reflector and at the beam splitter. The optical assembly is also configured to transmit a portion of the ambient light through the optical assembly at a second optical power without reflection at the reflector. The second optical power is less than the first optical power.

A total reflection screen comprises a light diffusion layer, a total reflection layer and a light absorption layer arranged sequentially from an incidence side of the projected light. The light absorption layer can absorb an incident light. The light diffusion layer is used for increasing a divergence angle of emergent light. The total reflection layer comprises a plurality of microstructure units that is rotationally symmetrical and extends continuously in a plane of the total reflection screen. Each of the microstructure units comprises a first material layer disposed at the side of the light diffusion layer and a second material layer disposed at the side of the light absorption layer. The interface between the first material layer and the second material layer is comprised of two intersecting planes, which are disposed in such a way that the projected light is subjected to total reflection continuously at the two intersecting planes.

An optical element is provided. The optical element includes an optical film including a birefringent material having a chirality. Optically anisotropic molecules of the birefringent material disposed adjacent a first surface of the optical film are configured with a first pretilt angle in a range of greater than 10° and less than 80°, or in a range of greater than −80° and less than −10°. Optically anisotropic molecules of the birefringent material disposed adjacent a second surface of the optical film opposing the first surface are configured with a second pretilt angle in the range of greater than 10° and less than 80°, or in the range of greater than −80° and less than −10°.

A diffusive layer including a laminate of a plurality of transparent films is provided. At least one of the plurality of transparent films includes a plurality of diffusive elements with a concentration that is less than a percolation threshold. The plurality of diffusive elements are optical elements that diffuse light that is impinging on such element. The plurality of diffusive elements can be diffusively reflective, diffusively transmitting or combination of both. The plurality of diffusive elements can include fibers, grains, domains, and/or the like. The at least one film can also include a powder material for improving the diffusive emission of radiation and a plurality of particles that are fluorescent when exposed to radiation.

A method for controlling a digital device according to the present application can control the device so as to execute a command corresponding to a single fingerprint or a plurality of fingerprints using a sheet capable of simultaneously recognizing a plurality of fingerprints. Accordingly, a user's usability can be greatly improved, and a complicated encryption function using a plurality of fingerprints can be implemented, so that the security of the digital device can be greatly improved.

The present disclosure provides a structured retroreflector. The structured retroreflector includes a transparent substrate, a plurality of transflective structure layers disposed on one side of the transparent substrate and mutually laminated and parallel, wherein distances between any two adjacent transflective structure layers are equal and 0.1λ to 10λ, λ being a wavelength of incident light, and a transparent filling layer disposed between any two adjacent transflective structure layers.

A display device includes a display having optically anisotropic molecules disposed between a front surface and a back surface. The display is configurable to either receive image light and diffuse the image light to output diffused image light from the front surface, or to transmit ambient light from the back surface to the front surface. The display device also includes an optical assembly that has a substrate, a reflector, and a beam splitter. The optical assembly is configurable to transmit a portion of the diffused image light at a first optical power via an optical path including reflections at the reflector and at the beam splitter and to transmit a portion of the ambient light output from the front surface of the display at a second optical power without reflection at the reflector. The second optical power is less than the first optical power.

An optical assembly includes a reflector and a volume Bragg grating (VBG). The VBG is positioned for: (i) transmitting light having a first polarization and incident upon the VBG at an incident angle that is within a first angular range, (ii) reflecting light having the first polarization and incident upon the VBG at an incident angle that is within a second angular range distinct from the first angular range, and (iii) transmitting light having a second polarization different from the first polarization. The optical assembly is configured to receive first light, having the first polarization, and reflect the first light at the reflector and at the VBG before the first light is output from the optical assembly. The optical assembly is configured to receive second light, having the second polarization, and output the second light from the optical assembly without undergoing reflection at either the reflector or the VBG.

This reflective screen 10 reflects a part of image light beam projected from an image source LS, to display an image. The reflective screen 10 is provided with: a first optical shape layer 12 which has optical transparency and has a plurality of unit optical shapes 121 arranged on a rear surface thereof; and a reflective layer 13 which is formed in at least some of the unit optical shapes 121 and by which a part of incident light is reflected and at least the other part of the incident light is transmitted, wherein a light diffusing action in the direction in which the unit optical shapes 121 are arranged is larger than a light diffusing action in a direction perpendicular to the arrangement direction.