A diffractive optical element comprises a substrate, a first resin layer arranged on the substrate and a second resin layer arranged on the first resin layer. Each of the first resin layer and the second resin layer includes a grating section, or a layer portion, for forming a diffraction grating and a base section, or another layer portion, held in contact with the grating section. Either the first resin layer or the second resin layer has a lower transmittance portion in the base section thereof that shows an internal transmittance relative to a wavelength of 400 nm which is lower than that of the grating section of the resin layer by not less than 2% and not more than 6%.

An optical identifier including a recording surface, a plurality of deflection cells each of which has recorded thereon a range in which light to be diffracted is deflected, at least one spatial phase modulator which fills a space between the deflection cells on the recording surface, and a deposition layer which covers part or all of the recording surface. The deflection cells has a spatial frequency expressed in a form of a relief structure and are discretely formed on the recording surface at regular intervals away from each other. A variable color image is recorded by pixels defined by the deflection cells. The spatial phase modulator has thereon a distribution of phase differences recorded in a form of heights of the relief structure. The spatial phase modulator modulates a phase of light outputted from a point light source and displays a reproduced image.

An optical device includes first and second planar substrates having respective first and second faces and including first and second diffractive structure disposed respectively on the first and second faces. First and second planar electrodes are disposed respectively on the first and second faces. A mount holds the second planar substrate parallel to the first planar substrate, with the second face adjacent to the first face and with the first and second planar electrodes in mutual proximity, while permitting the second planar substrate to move transversely relative to the first planar substrate. A control circuit is coupled to apply an electrical potential between the first and second planar electrodes with a voltage sufficient to shift the second diffractive structure transversely relative to the first diffractive structure.

Provided are a cholesteric liquid crystal film including a cholesteric liquid crystal, in which the cholesteric liquid crystal film has a stripe pattern in which dark portions and bright portions are alternately arranged in a straight line on an upper surface observed with a microscope; and a manufacturing method thereof.

A diamond turning station having a drum able to be rotated about an axis C and a diamond tip. A piece to be machined P is installed on the drum as follows: the piece to be machined P is offset by a distance D from the rotation axis of the drum; the piece to be machined P is placed so that there is a mean angle Theta between the axis C and a cutting profile corresponding to the active surfaces, the angle Theta being as follows: Theta=arccos (D/Ry), where Ry is a radius of curvature required in the long direction of the microstructures. Next, the diamond tip is moved along the cutting profile of the microstructures, while actuating the rotation of the drum, so as to machine all the microstructures on the surface of the piece to be machined P.

A system for fabricating coded lenses includes a cutting tool configured to controllably cut a workpiece at a specified position-dependent depth while traversing a surface of the workpiece along a specified two-dimensional path. A signal generator is operative to generate a signal for controlling fabrication of a coded lens from the workpiece. A vibration tool is operative to ultrasonically vibrate the cutting tool for cutting of gratings on the workpiece.

A metallic grating is formed to include a substrate; a plurality of high aspect ratio trenches disposed in the substrate such that the high aspect ratio trenches are spaced apart from one another by a field surface of the substrate; a metallic superconformal filling formed and disposed in the high aspect ratio trenches; and a grating including a spatial arrangement of the high aspect ratio trenches that are filled with the metallic superconformal filling such that the metallic superconformal filling is void-free, and the high aspect ratio trenches are bottom-up filled with the metallic superconformal filling, wherein a height of the metallic superconformal filling is less than or equal to the height of the high aspect ratio trenches.

Systems and methods for fabricating optical elements in accordance with various embodiments of the invention are illustrated. One embodiment includes a method for fabricating an optical element, the method including providing a first optical substrate, depositing a first layer of a first optical recording material onto the first optical substrate, applying an optical exposure process to the first layer to form a first optical structure, temporarily erasing the first optical structure, depositing a second layer of a second optical recording material, and applying an optical exposure process to the second layer to form a second optical structure, wherein the optical exposure process includes using at least one light beam traversing the first layer.

A color display of an embodiment includes: an embossed layer; a high refractive index layer; and a protective layer, laminated in this order, wherein the high refractive index layer has a highest refractive index among these layers, the embossed layer includes a first region having a periodic structure with a period at least smaller than a center wavelength of visible light, a plurality of the first regions, each having a strip shape, are connected to each other at their longitudinal end sides, the first regions being offset from each other in a direction perpendicular to a longitudinal direction of the strip shape, as viewed via a display surface, and a periodic direction of the periodic structure is parallel to the longitudinal direction.

The present invention provides a concave diffraction grating and an optical device using the concave diffraction grating, the concave diffraction grating being capable of preventing deformation of a reflection film due to the influence of temperature, and preventing deterioration in optical characteristic due to temperature. This concave diffraction grating is provided with: a reflection film (22) having a plurality of grating grooves (21); a holding film (25) comprising metal and having one surface on which the reflection film (22) is provided; a concave substrate (24) having a concave surface (24a); and an affixing layer (23) provided between the concave surface (24a) and the other surface of the holding film (25), and affixing the holding film (25) and the reflection film (22) to the concave substrate (24).