398 results about "Holographic optical element" patented technology

A method for displaying an image viewable by an eye, the image being projected from a portable head worn display, comprises steps of: emitting a plurality of light beams of wavelengths that differ amongst the light beams; directing the plurality of light beams to a scanning mirror; modulating in intensity each one of the plurality of light beams in accordance with intensity information provided from the image, whereby the intensity is representative of a pixel value within the image; scanning the plurality of light beams in two distinct axes with the scanning mirror to form the image; and redirecting the plurality of light beams to the eye using a holographic optical element acting as a reflector of the light beams, whereby the redirecting is dependent on the wavelength of the light beam, to create for each light beam an exit pupil at the eye that is spatially separated from the exit pupils of the other light beams.

A device, such as a heads up display, includes equipment for generating a virtual image in the field of view of an observer. The equipment includes at least one light source having a wavelength range less than 2 nm. The light source can be a low pressure gas discharge lamp. The device also includes a holographic optical element that provides a virtual image. The device also includes an image source, such as a mask or an LCD. In one embodiment the holographic optical element combines an image on a display with an ambient image. The holographic element provides multiple colors undistorted in a virtual image appearing to the observer as converging from the same distance.

One embodiment of the invention comprises a simplified light-weight head mounted displays comprising an off-axis combiner and a pair of plastic lenses. One of the lenses is a rotationally symmetric optical element and one of the lens is a non-rotationally symmetric optical element. This non-rotationally symmetric optical element comprises first and second lens surfaces that are tilted and decentered with respect to each other. One of these first and second lens surfaces may also include diffractive feature to provide a diffractive or holographic optical element for color correction.

The present invention provides a large format fingerprint capture apparatus, system and method that is low power, compact, and lightweight and has a platen area greater than 3.0 square inches. The present system is typically powered, controlled, and exchanges data over a single data/control/power connection to a host PC, e.g., a desk top computer, PDA, or laptop computer although the system can also be used in a wireless fashion with a power subsystem so no physical connections are required. In a preferred embodiment the large format fingerprint device is directly connected to a completely disconnected portable PC, such as a laptop having only a battery power source. The primary system components of the present invention combine to minimize power, size and weight and, thus, enhance portability and battery life. The system typically includes a light source, a prism, a camera (including the lens), and a case. Optional elements comprise holographic elements such as gratings and holographic optical elements (HOEs), a battery subsystem, magnetic stripe reader, barcode reader, platen heater, platen blower, and mirrors to divert the image beam.

Systems, devices, and methods that integrate eye tracking capability into scanning laser projector (“SLP”)-based wearable heads-up displays are described. An infrared laser diode is added to an RGB SLP and an infrared photodetector is aligned to detect reflections of the infrared light from features of the eye. A holographic optical element (“HOE”) may be used to combine visible light, infrared light, and environmental light into the user's “field of view.” The HOE may be heterogeneous and multiplexed to apply positive optical power to the visible light and zero or negative optical power to the infrared light.

Systems, devices, and methods that integrate eye tracking capability into scanning laser projector (“SLP”)-based wearable heads-up displays are described. An infrared laser diode is added to an RGB SLP and an infrared photodetector is aligned to detect reflections of the infrared light from features of the eye. A holographic optical element (“HOE”) may be used to combine visible light, infrared light, and environmental light into the user's “field of view.” The HOE may be heterogeneous and multiplexed to apply positive optical power to the visible light and zero or negative optical power to the infrared light.

Embodiments of illumination-based medical devices capable of projecting a holographic symbol are herein provided. In one embodiment, an illumination-based medical device incorporates at least a laser and a diffractive optical element within a housing. In one embodiment, the diffractive optical element may be a holographic optical element. In a particular embodiment, the holographic optical element may incorporate an interference pattern and/or a sacred symbol or pattern.

An optical switch formed of a holographic optical element (HOE) disposed above a top surface of a substrate and moveable relative thereto is shown. Light is traveling through the substrate under total internal reflection, which creates an evanescent field extending beyond the reflecting surfaces of the substrate. The HOE is characterized, in one embodiment, by being formed from a plurality of strips that are moveable between a first position in which the strips are above the evanescent field and a second position in which the strips are inside the evanescent field. In the first position, the light in the substrate propagates unaffected by the HOE in a primary direction of propagation. In the second position, the light in the substrate is altered by the HOE and made to propagate in a reflected direction oblique to that of the primary direction of propagation.

An optical head-mounted display includes an eyeglass frame, a holographic optical element supported by the eyeglass frame to be confronted by an eye of a wearer, and a projector mounted on the eyeglass frame to project image information on the holographic optical element. The projector includes a LED light source, a beam-splitting polarizer, a spatial light modulator, a lens set and a mechanical one-dimensional scanner. The mechanical one-dimensional scanner reflects the transformed light beam from the lens set onto the holographic optical element in one dimension at a time. When the reflective sheet is rotated at a range of angle in a brief moment of time, the holographic optical element receives from the rotating reflective sheet an array of one-dimensional modulated light beams and reflects the latter to form a two-dimensional image in the eye because of persistence of vision.

An apparatus for image acquisition of topological features of the surface of skin. The apparatus comprises a waveguide, having an entrance edge and top and bottom surfaces; a light source, configured to direct a light beam at the entrance edge of the waveguide; a skin contact layer, disposed at or near the top surface of the waveguides; a holographic optical element (HOE), disposed at the top or at the bottom surfaces of the waveguide, configured to diffract the light beam incident from the light source to the skin contact layer; a sensor array, configured to detect light reflected from the surface of skin in contact with skin contact layer; and means for compensating for changes in the Bragg matching condition of the HOE due to temperature.

Switchable holographic optical elements (HOEs) can used in systems and methods for projecting three-dimensional images, or for projecting two-dimensional tiled images with increased size and/or resolution. One of the methods may include sequentially displaying first, second, and third color components of a first two-dimensional image at an object plane. The first two dimensional image represents a first slice of a three-dimensional image. As the first, second, and third color components are displayed, first, second and third HOEs may be activated so that the activated first switchable HOE focuses the first color component of the first two-dimensional image onto a first image plane, the activated second switchable HOE focuses the second color component of the first two-dimensional image onto the first image plane, and the wherein the activated third switchable HOE focuses the third color component of the first two-dimensional image onto the first image plane. It is noted that the first, second, and third HOEs may be activated concurrently or sequentially with the display of the first, second, or third color components of the first two-dimensional image. After the first, second, and third color components are displayed, the first, second and third switchable HOEs are deactivated. Then, first, second, and third color components of a second two-dimensional image are sequentially displayed. The second two-dimensional image represents a second slice of the three-dimensional image. A fourth switchable HOE may be activated to focus the first color component of the second two-dimensional image onto a second image plane. The second image plane is adjacent to the first image plane.

Systems, devices, and methods for combined angle- and wavelength multiplexing in holographic optical elements (“HOE”) are described. An angle- and wavelength-multiplexed HOE includes multiple angle-multiplexed sets of wavelength-multiplexed holograms. Each set of wavelength-multiplexed holograms includes at least two holograms that are each responsive to a different wavelength of light. Each angle-multiplexed set of wavelength-multiplexed holograms includes a respective set of wavelength-multiplexed holograms that are all responsive to light that is incident thereon with and angle of incidence that is within a particular range. An example application is described in which an angle- and wavelength-multiplexed HOE is used as a holographic combiner in a wearable heads-up display, where angle-multiplexing provides multiple spatially-separated exit pupils in the eyebox of the display and wavelength-multiplexing provides multiple colors to each respective exit pupil.

Systems, devices, and methods that integrate eye tracking capability into scanning laser projector (“SLP”)-based wearable heads-up displays are described. At least one narrow waveband laser diode is used in an SLP to define one or more portion(s) of a visible image. At least one corresponding narrow waveband photodetector is aligned to detect reflections of the portion(s) of the image from features of the eye. A holographic optical element (“HOE”) may be used to combine the image and environmental light into the user's “field of view.” Three narrow waveband photodetectors each responsive to a respective one of three narrow wavebands output by the RGB laser diodes of an RGB SLP are aligned to detect reflections of a projected RGB image from features of the eye.

Apparati and methods for generating a three-dimensionally perceived image from a stereo endoscope by at least one viewer include an autostereoscopic display having a left projector and a right projector that project corresponding left and right images received from corresponding left and right cameras of a stereo endoscope through a transmissive holographic optical element functioning as a Bragg diffraction grating to redirect light from the left projector to a left eye-box and to redirect light from the right projector to a right eye-box for viewing by left and right eyes of a viewer to create a three-dimensionally perceived image without glasses or optical headgear.

A device for combining tomographic images with human vision using a half-silvered mirror to merge the visual outer surface of an object (or a robotic mock effector) with a simultaneous reflection of a tomographic image from the interior of the object. The device maybe used with various types of image modalities including ultrasound, CT, and MRI. The image capture device and the display may or may not be fixed to the semi-transparent mirror. If not fixed, the imaging device may provide a compensation device that adjusts the reflection of the displayed ultrasound on the half-silvered mirror to account for any change in the image capture device orientation or location.

A holographic see-through optical device, a stereoscopic imaging system including the same, and a multimedia head mounted system are provided. The holographic see-through optical device includes a micro display; a relay optical system, which relays an image generated by the micro display; at least one waveguide comprising at least two portions having different thicknesses or different refractive indexes; at least one first holographic optical element, which is arranged at one of the two portions; and at least one second holographic optical element, which is arranged at the other one of the two portions.

A solar concentrator receives sunlight for generating solar power with the concentrator including holographic optical element (HOE) separators for separating sunlight into separated bands, including HOE concentrators for concentrating the separated bands into concentrated bands, including HOE reflectors for reflecting the concentrated bands as reflected bands onto a multiple junction photovoltaic solar cell for generating the solar power with reduced aberrations of the bands for improved conversion of the solar light into the generator solar power, all of which can be constructed in an integrated structure using spacers, waveguides, and a substrate, where the HOEs use chirp Bragg gratings for reducing optical aberrations of the separated, concentrated, and reflected optical bands, with the option of multiple HOE separators for receiving sunlight from various angles of incidence.

A projection display system includes (1) a polarizer, (2) a holographic screen with holographic optical elements having the properties of a display portion and a polarizing portion, and (3) a projector for projecting an image through the polarizer and onto the holographic screen. The polarizing portion of the holographic screen has a different polarization direction from the polarizer such that the image is visible from a first side of the holographic screen and invisible from a second side of the holographic screen.

A diffractive display system and a method of collecting first order light beams from a diffractive display of the system utilize holographic optical elements (HOEs) to deflect one of two first order diffracted light beams that emerge from each diffracting pixel of the diffractive display, so that the first order diffracted light beams can be separated from the zeroth order light beams. The utilization of the HOEs allows the system to be implemented in a compact optical configuration, without sacrificing any portion of the first order diffracted light. In a first embodiment, the system includes three HOEs that have static diffracting properties that are optimized for red, green and blue lights. For each set of light beams from a diffracting pixel of the diffractive display, the HOEs are holographically configured to deflect only one of the two first order diffracted light beams, such that the deflected first order light beam propagates in the same direction as the other non-deflected first order light beam. In a second embodiment, the system includes three HOEs that have reconfigurable diffracting properties that are also optimized for red, green and blue lights. In a third embodiment, the system further includes a holographic color filter that is comprised of three reconfigurable HOEs to sequentially illuminate the diffractive display with each of the tristimulus color lights.