7608results about "Diffraction gratings" patented technology

A diffractive beam expander (50) comprises an input grating (10), a crossed grating (20), and an output grating (30) implemented on a planar transparent substrate (7). The crossed grating (20) comprises a plurality of diffractive features (23) arranged along the lines of a first set of parallel lines (25) and along the lines of a second set of parallel lines (26) such that the lines (25) of the first set are parallel to the lines (26) of the second set. The lines of the first set have a first grating period and the lines of the second set have a second grating period. A light beam (B1) coupled into the substrate (7) by the input grating (10) impinges on the crossed grating (20) at a first location (EC1) and further locations (EC2). Interaction at the first location (EC1) provides several sub-beams (S00, S01, S10) which propagate in different directions. Further interactions at second locations (EC2) provide further sub-beams (V01, U10) which propagate in the same direction as the original in-coupled light (B1). Light is subsequently coupled out of the substrate (7) by the output grating (30) to provide a light beam (B2) which is expanded in two directions (SX, SZ) with respect to the beam (B0) impinging on the input grating. A virtual display device (200) may comprise said diffractive beam expander (50).

An exit pupil extender wherein the relative amount of different color components in the exit beam is more consistent with that of the input beam. In order to compensate for the uneven amount in the diffracted color components in the exit beam, the exit pupil extender, comprises a plurality of layers having additional diffraction gratings so as to increase the amount of diffracted light for those color components with a lower amount. Additionally, color filters disposed between layers to reduce the diffracted light components with a higher amount.

An optical apparatus for transmitting light having a spectrum of wavelengths is disclosed. The apparatus comprises a plurality of optical devices design and constructed to decompose the light into a plurality of portions, respectively corresponding to different sub-spectra of the spectrum, such that each portion of the light is transmitted within a different optical device.

An optical apparatus for transmitting light having a spectrum of wavelengths is disclosed. The apparatus comprises a plurality of optical devices design and constructed to decompose the light into a plurality of portions, respectively corresponding to different sub-spectra of the spectrum, such that each portion of the light is transmitted within a different optical device.

A library of simulated-diffraction signals for an integrated circuit periodic grating is generated by generating gets of intermediate layer data. Each set of intermediate layer data corresponding to a separate one of a plurality of hypothetical layers of a hypothetical profile of the periodic grating. Each separate hypothetical layer has one of a plurality of possible combinations of hypothetical values of properties for that hypothetical layer. The generated sets of intermediate layer data are stored. Simulated-diffraction signals for each of a plurality of hypothetical profiles are generated based on the stored generated sets of intermediate layer data.

There is provided an optical device for transferring light within a given field-of-view, comprising an input aperture; reflecting surfaces, and an output aperture located in spaced-apart relationship from the input aperture such that light waves, located within the field-of-view, that enter the optical device through the input aperture, exit the optical device through the output aperture, wherein the reflecting surfaces are at least one pair of parallel reflecting surfaces and that part of the light waves located within the field-of-view that enter the input aperture, pass directly to the output aperture without being reflected off the at least one pair of parallel reflecting surfaces, while another part of the light waves within the field-of-view that enters the input aperture, arrives at the output aperture after being twice reflected by the at least one pair of parallel reflecting surfaces.

A head-mounted display system displays information via a matrix display element mounted within a housing that is positioned relative to at least eye of a user. The display is connected to a video or information source such that the user can view information or images shown on the display. The display can be mounted to a frame so that the user can move the display in and out of the user's field of view without adjusting the supporting harness that holds the display on the user's head.

Provided is a light emitting device including a Fresnel lens and / or a holographic diffuser formed on a surface of a semiconductor light emitter for improved light extraction, and a method for forming such light emitting device. Also provided is a light emitting device including an optical element stamped on a surface for improved light extraction and the stamping method used to form such device. An optical element formed on the surface of a semiconductor light emitter reduces reflective loss and loss due to total internal reflection, thereby improving light extraction efficiency. A Fresnel lens or a holographic diffuser may be formed on a surface by wet chemical etching or dry etching techniques, such as plasma etching, reactive ion etching, and chemically-assisted ion beam etching, optionally in conjunction with a lithographic technique. In addition, a Fresnel lens or a holographic diffuser may be milled, scribed, or ablated into the surface. Stamping, an alternative method for forming an optical element, can also be used to form a Fresnel lens or a holographic diffuser on the surface of a semiconductor light emitter. Stamping includes pressing a stamping block against the surface of a light emitting diode. The stamping block has a shape and pattern that are the inverse of the desired optical element. Optionally, stamping can be done before, after, or concurrently with wafer-bonding. Alternatively, a material can be stamped and later bonded to the semiconductor light emitter.

An imaging system is presented for imaging objects within a field of view of the system. The imaging system comprises an imaging lens arrangement, a light detector unit at a certain distance from the imaging lens arrangement, and a control unit connectable to the output of the detection unit. The imaging lens arrangement comprises an imaging lens and an optical element located in the vicinity of the lens aperture, said optical element introducing aperture coding by an array of regions differently affecting a phase of light incident thereon which are randomly distributed within the lens aperture, thereby generating an axially-dependent randomized phase distribution in the Optical Transfer Function (OTF) of the imaging system resulting in an extended depth of focus of the imaging system. The control unit is configured to decode the sampled output of the detection unit by using the random aperture coding to thereby extract 3D information of the objects in the field of view of the light detector unit.