Abstract: A method includes disposing a hardmask coating atop a substrate and forming first openings through the hardmask coating. The method further includes forming a ramped resist coating atop the hardmask coating, the ramped resist coating sloping from a first end of the substrate to a second end of the substrate. The method even further includes etching a plurality of varying depth notches having varying depths within the substrate at locations corresponding to the first openings, the plurality of varying depth notches forming a substantially linearly increasing depth grating within the substrate.

Abstract: Methods and systems for manufacturing an optical waveguide include depositing an adhesion promoting layer on a substrate. Multiple curable resist droplets are dispensed on the adhesion promoting layer. The adhesion promoting layer is disposed between and contacts the substrate and the curable resist droplets. The curable resist droplets define an optical eyepiece layer such that a zero residual layer thickness (RLT) region of the optical eyepiece layer is free of the curable resist droplets. The optical eyepiece layer is incised from the substrate to form the optical waveguide.

Abstract: Optical waveguides are formed based on measured parameters of an optical substrate. Regions for forming one or more optical elements are identified based on these measurements, and inkjet deposition is utilized to deposit a refraction-matched deposition material is applied to one or more identified regions to selectively modify the total thickness variation (TTV) in each such region. Prior to or subsequent to the deposition, optical gratings or other optical elements are formed within the adjusted regions.

Abstract: A fabrication process uses casting to form portions of a waveguide having ultra-flat surfaces. A casting resin is coated between a prism mold and a top flat mold via inkjet, slot die, spray coating, etc. The top flat mold is lowered to conform with the casting resin and the casting resin is then cured to form a bottom prism array. After curing, the bottom prism array is demolded from the prism mold and the top flat mold is used as a carrier wafer to support the bottom prism array. The bottom prism array is selectively coated with a reflective coating and a second casting process is performed by coating the bottom prism array with casting resin to form a reflective waveguide.

Abstract: A method of nanoimprinting a waveguide includes forming a working stamp having at least one waveguide feature pattern and at least one process control feature pattern. The working stamp is pressed into a waveguide workpiece thereby forming waveguide features in one or more functional waveguide zones of the waveguide workpiece and one or more sets of process control features in one or more regions outside of the one or more functional waveguide zones. The working stamp is detached from the waveguide workpiece.

Abstract: Techniques for fabricating a polymer reflective waveguide mold with high structural quality control (flatness, alignment, dimensions) and high precision and groove parallelism for high optical quality include using optical lithography and wet etch process. For example, a method of fabricating a reflective waveguide mold includes depositing a hard mask layer on a crystalline substrate, lithographically patterning the hard mask layer, and anisotropically removing the crystalline substrate to form a prism array waveguide mold.

Abstract: Techniques are described for applying an edge sealant to the edge of a multi-layer optical device. In particular, embodiments provide an apparatus that performs a precision measurement of the perimeter of an eyepiece, applying the edge sealant (e.g., polymer) based on the precision-measured perimeter, and subsequently cures the edge sealant, using ultraviolet (UV) light that is directed at the edge sealant. The curing process may be performed within a short time following the application of the edge sealant, to ensure that any wicking of the edge sealant between the layers of the eyepiece is controlled to be no greater than a particular depth tolerance. In some examples, the edge sealant is applied to the optical device prevent, or at least reduce, the leakage of light from the optical device, and also to ensure and maintain the structure of the multi-layer optical device.

Abstract: An optical device, such as an eyepiece, including multiple layers of waveguides. The optical device can include an edge sealant for reducing light contamination, a lamination dam to restrict the wicking of the edge sealant between layers of the optical device, and venting gap(s) in the sealant and dam to allow air flow between the exterior and interior of the eyepiece. The gap(s) allow outgassing from the interior of the eyepiece of unreacted polymer and/or accumulated moisture, to prevent defect accumulation caused by chemical reaction of outgassed chemicals with the (e.g., ionic, acidic, etc.) surface of the eyepiece layers. The gap(s) also prevent pressure differences which may physically deform the eyepiece over time.

Abstract: A method for fabricating a working stamp for forming surface gratings in a waveguide workpiece includes performing a series of step lithography processes using a series of master stamps so as to form a working stamp having a first surface having a plurality of surface gratings formed therein. Each step lithography process includes pressing a master stamp of the series of master stamps into a material layer of a working stamp workpiece at a corresponding region of the material layer, the master stamp having a plurality of surface grating patterns formed thereon. Each step lithography process further includes applying ultraviolet light to the corresponding region to locally cure the material layer at the corresponding region and detaching the master stamp from the material of the working stamp after applying the ultraviolet light.

Abstract: An augmented-reality (AR) eyewear display utilizes an optical waveguide having multi-layered optical gratings in a repeating arrangement. The optical gratings include varying depths, slope angles, lengths, and/or widths in order to tune the gratings to provide an improved AR eyewear display. By using the different configurations of two-dimensional or three-dimensional gratings disclosed herein in a waveguide of an AR eyewear display, optical characteristics of the waveguide are optimized to provide, e.g., high resolution and/or contrast, high display uniformity, high input coupling efficiency, and/or high output coupling efficiency. Accordingly, in some embodiments, aspects of the present disclosure enable lower-power AR eyewear displays to produce the same quality of display of a higher-power conventional AR eyewear display waveguide.

Abstract: An optical device, such as an eyepiece, including multiple layers of waveguides. The optical device can include an edge sealant for reducing light contamination, a lamination dam to restrict the wicking of the edge sealant between layers of the optical device, and venting gap(s) in the sealant and dam to allow air flow between the exterior and interior of the eyepiece. The gap(s) allow outgassing from the interior of the eyepiece of unreacted polymer and/or accumulated moisture, to prevent defect accumulation caused by chemical reaction of outgassed chemicals with the (e.g., ionic, acidic, etc.) surface of the eyepiece layers. The gap(s) also prevent pressure differences which may physically deform the eyepiece over time.

Abstract: Systems and methods are provided for generating a two-dimensional pattern on a photoresist layer. A photoresist layer is exposed via a first exposure to a first unidimensional series of features alternatingly providing first minima and maxima of illumination intensity along a first dimension. The photoresist layer is then exposed via a second exposure to a second unidimensional series of features alternatingly providing second minima and maxima of illumination intensity along a second dimension that is angularly separated from the second dimension by an exposure rotation factor.

Abstract: A method for fabricating a working stamp for forming slanted surface gratings in a waveguide workpiece includes providing a master workpiece comprising a substrate and performing a sequence of photoresist deposition processes, grayscale lithography processes, and etching processes on the master workpiece so as to form an imprint replication master having a pattern of slanted gratings in a working surface of its substrate, the slanted gratings having sidewalls that are not substantially orthogonal to a working surface of the substrate. The method also includes conforming a soft stamp material layer to the working surface of the imprint replication master so that the soft stamp material layer has a pattern of slanted protrusions corresponding to the pattern of slanted gratings, and removing the imprint replication master from the soft stamp material and curing the soft stamp material layer surrounding the pattern of slanted protrusions to form the working stamp.

Abstract: A method for fabricating a working stamp for forming surface gratings in a waveguide workpiece includes performing a series of step lithography processes using a series of master stamps so as to form a working stamp having a first surface having a plurality of surface gratings formed therein. Each step lithography process includes pressing a master stamp of the series of master stamps into a material layer of a working stamp workpiece at a corresponding region of the material layer, the master stamp having a plurality of surface grating patterns formed thereon. Each step lithography process further includes applying ultraviolet light to the corresponding region to locally cure the material layer at the corresponding region and detaching the master stamp from the material of the working stamp after applying the ultraviolet light.

Abstract: An augmented-reality (AR) eyewear display utilizes an optical waveguide having multi-layered optical gratings in a repeating arrangement. The optical gratings include varying depths, slope angles, lengths, and/or widths in order to tune the gratings to provide an improved AR eyewear display. By using the different configurations of two-dimensional or three-dimensional gratings disclosed herein in a waveguide of an AR eyewear display, optical characteristics of the waveguide are optimized to provide, e.g., high resolution and/or contrast, high display uniformity, high input coupling efficiency, and/or high output coupling efficiency. Accordingly, in some embodiments, aspects of the present disclosure enable lower-power AR eyewear displays to produce the same quality of display of a higher-power conventional AR eyewear display waveguide.

Abstract: A device for a timepiece, comprising a support, an inertial regulating member mounted so as to rotate relative to the support by an elastic suspension connecting said regulating member to the support. The regulating member comprises a number n of rigid portions interconnected in pairs by n elastic coupling links. The elastic suspension comprises n elastic suspension links respectively connecting each rigid portion to the support.

Abstract: An improved nanoimprint lithography process is presented in which the height is controlled by the thickness of a residual layer of resin leftover after ultraviolet curing and releasing of a nanoimprint mold from a resin layer. Moreover, the thickness of the residual layer may be controlled by a fill factor of either a nanoimprint mold that transfers its pattern to a resin layer disposed on a substrate, or by droplets of resin in the resin layer.

Abstract: Methods and apparatuses related to fiducial designs for fiducial markers on glass substrates, or other transparent or translucent substrates, are disclosed. Example fiducial designs can facilitate visual recognition by enhancing edge detection in visual perception. In example fiducial designs, optical features on glass substrates can re-direct light so as to present a bright image region. Such optical features can include surface relief patterns formed in a coating on the surface of glass substrates. An exemplary method for manufacturing the fiducial markers can involve transfers of a fiducial design across a master mold or plate, a submaster mold or plate, and a target glass substrate. A fiducial marker can facilitate the use of the substrate in a variety of applications, including machine vision systems that facilitate automated performance of manufacturing processes on input working material.

Abstract: Techniques are described for applying an edge sealant to the edge of a multi-layer optical device. In particular, embodiments provide an apparatus that performs a precision measurement of the perimeter of an eyepiece, applying the edge sealant (e.g., polymer) based on the precision-measured perimeter, and subsequently cures the edge sealant, using ultraviolet (UV) light that is directed at the edge sealant. The curing process may be performed within a short time following the application of the edge sealant, to ensure that any wicking of the edge sealant between the layers of the eyepiece is controlled to be no greater than a particular depth tolerance. In some examples, the edge sealant is applied to the optical device prevent, or at least reduce, the leakage of light from the optical device, and also to ensure and maintain the structure of the multi-layer optical device.

Abstract: A disconnector trigger bar safety for a semi-automatic pistol is provided and includes a trigger bar having a firing pin end having a sear surface and a cam surface. The trigger bar has an inside surface disposed adjacent to the cam surface. A disconnector is moveable from an inward position to an outward position and has a cam surface to receive the cam surface of a trigger bar. An inset portion is provided on the trigger bar at the firing pin end that has a bottom surface. A protuberance on the side of the disconnector is provided to mate with the inset portion of the trigger bar. The protuberance has a top surface matable to the bottom surface of the inset portion. Rearward movement of the trigger bar causes the cam surface of the trigger bar to slide against the cam surface of the disconnector to move the firing pin end of the trigger bar downwardly. The disconnector moves to provide clearance for the trigger bar to move upward.