The invention relates to a method of fabricating a master plate for producing diffractive structures and a master plate obtainable therewith. The method comprises providing a substrate having a periodic surface profile, filling the surface profile uniformly at least partly with filling material, and partially removing the filling material in order to produce a master plate having a periodic height-modulated surface profile formed by said substrate and said filling material. The invention allows for producing master plates capable of further producing gratings with variable diffraction efficiency.

Easy and accurate mating of a groove interval of a groove pattern of a diffraction grating with a position on a convex fixing substrate is enabled. For this purpose, a concave diffraction grating is fabricated by: transferring a groove pattern formed on a plane diffraction grating and having unequal groove intervals onto a metal thin film; forming a first alignment mark on a convex surface of a fixing substrate having the convex surface to fix the metal thin film; mating a second alignment mark formed on an adhesive surface of the metal thin film with the first alignment mark to perform alignment; bonding the adhesive surface of the metal thin film and the convex surface of the fixing substrate to each other to fabricate a master; and transferring a groove pattern of a metal thin film of the master.

Color-selective waveguides, methods for fabricating color-selective waveguides, and augmented reality (AR)/mixed reality (MR) applications including color-selective waveguides are described. The color-selective waveguides can advantageously reduce or block stray light entering a waveguide (e.g., red, green, or blue waveguide), thereby reducing or eliminating back-reflection or back-scattering into the eyepiece.

An objective of the present invention is to improve a diffraction grating. A molding member including a substrate and a resist pattern having a surface shape including grooves is prepared. The grooves include bottom portions BP1 and top portions TP1 that are alternately repeated in an X direction, and that each extend in a Y direction. The bottom portions adjacent to each other have an interval that changes stepwise. Next, a metal film is formed on a surface of the resist pattern to cover the grooves, and then the metal film is peeled off from the molding member. As a result, the metal film is formed to have a surface shape reverse to the surface shape of the resist pattern is formed. Top portions TP2 and bottom portions BP2 of the metal film correspond to bottom portions BP1 and top portions TP1 of the resist pattern respectively.

A method of forming an article which includes a diffraction grating, an article, and an apparatus for forming the article by printing are described. The method includes forming a periodic structure by printing a first set of parallel lines on a first side of a transparent substrate with a marking material and printing a second set of parallel lines on a second side of the transparent substrate with a marking material, the first and second sets of lines, in combination, defining a grating having a frequency and a spacing between lines which causes incident light to be diffracted into a plurality of beams travelling in different directions.

Embodiments provided herein provide for amorphous encapsulation of nanoparticle imprint films for optical devices. In one embodiment provided herein, a device is provided. The device includes a plurality of optical device structures disposed on a surface of a substrate. The plurality of optical device structures include a nanoparticle imprint material. The plurality of optical device structures further include an encapsulation layer disposed over at least a top surface and one sidewall of each optical device structure of the plurality of optical device structures. The encapsulation layer is amorphous or substantially amorphous. The encapsulation layer includes a niobium oxide. The niobium oxide is selected from the group consisting of niobium monoxide (NbO), niobium dioxide (NbO.sub.2), niobium pentoxide (Nb.sub.2O.sub.5), Nb.sub.12O.sub.29, Nb.sub.47O.sub.116, or Nb3n.sub.+1O.sub.8n−2, where n is 5 to 8.

Disclosed is an improved diffraction structure for 3D display systems. The improved diffraction structure includes an intermediate layer that resides between a waveguide substrate and a top grating surface. The top grating surface comprises a first material that corresponds to a first refractive index value, the underlayer comprises a second material that corresponds to a second refractive index value, and the substrate comprises a third material that corresponds to a third refractive index value. According to additional embodiments, improved approaches are provided to implement deposition of imprint materials onto a substrate, which allow for very precise distribution and deposition of different imprint patterns onto any number of substrate surfaces.

Methods of producing grating materials with variable height fins are provided. In one example, a method may include providing a mask layer atop a substrate, the mask layer including a first opening over a first processing area and a second opening over a second processing area. The method may further include etching the substrate to recess the first and second processing areas, forming a grating material over the substrate, and etching the grating material in the first and second processing areas to form a plurality of structures oriented at a non-zero angle with respect to a vertical extending from a top surface of the substrate.

Techniques for overcoating slanted structures and devices obtained using the techniques are disclosed. In some embodiments, a method of forming an overcoat layer on a surface-relief structure on a substrate includes receiving the substrate with the surface-relief structure. The surface-relief structure includes a plurality of ridges slanted with respect to the substrate, and a plurality of grooves each between two adjacent ridges. The method further includes depositing, in each cycle of a plurality of cycles, a uniform layer of an overcoat material on surfaces of the plurality of ridges and bottoms of the plurality of grooves. The deposited layers of the overcoat material and the plurality of ridges collectively form a light-coupling structure on the substrate. A surface of the overcoat layer is planar.

A diffractive pigment includes diffractive pigment, includes a stack including alternating layers of a high refractive index layer and a low refractive index layer, in which the high refractive index layer is a composition including an organic material and high refractive index inorganic nanoparticles; in which at least one layer of the stack is embossed. A method of making a diffractive pigment is also disclosed.