397 results about "Light diffraction" patented technology

Holographic optical elements (HOEs) can be used in systems and methods for providing illumination and for projecting images. The HOEs may be switchable HOEs, whose diffractive properties can be controlled. Described herein is a method of combining light from two or more illumination sources. In one embodiment, a reflection-type HOE is illuminated by the first illumination source. The HOE diffracts light from the first illumination source into an output direction. Light from the second illumination source is transmitted through the HOE and onto a reflective optical element, which reflects the light back through the HOE and into the same output direction. Also described is a projection system that uses two or more HOEs to combine two or more colors of light for use by a single image display. The system includes one or more light sources, an image display (such as a reflective or transmissive LCD display or a MEMS display, for example), and a first and a second HOE. The HOEs are each mounted between a light source and the image display, and configured to provide one color of light to the image display and from the image display into an output direction. In one embodiment, the HOEs are switchable HOEs and can be used for color-sequential display and / or for color balancing.

Diffractive lenses for vision correction are provided on a lens body having a first diffractive structure for splitting light into two or more diffractive orders to different focal distances or ranges, and a second diffractive structure, referred to as a multiorder diffractive (MOD) structure, for diffracting light at different wavelengths into a plurality of different diffractive orders to a common focal distance or range. In a bifocal application, the first and second diffractive structures in combination define the base power for distance vision correction and add power for near vision correction of the lens. The first and second diffractive structures may be combined on the same surface or located on different surfaces of the lens. The first diffractive structure may have blazed (i.e., sawtooth), sinusoidal, sinusoidal harmonic, square wave, or other shape profile. A sinusoidal harmonic diffractive structure is particularly useful in applications where smooth rather than sharp edges are desirable.

Diffractive lenses for vision correction are provided on a lens body having a first diffractive structure for splitting light into two or more diffractive orders to different focal distances or ranges, and a second diffractive structure, referred to as a multiorder diffractive (MOD) structure, for diffracting light at different wavelengths into a plurality of different diffractive orders to a common focal distance or range. In a bifocal application, the first and second diffractive structures in combination define the base power for distance vision correction and add power for near vision correction of the lens. The first and second diffractive structures may be combined on the same surface or located on different surfaces of the lens. The first diffractive structure may have blazed (i.e., sawtooth), sinusoidal, sinusoidal harmonic, square wave, or other shape profile. A sinusoidal harmonic diffractive structure is particularly useful in applications where smooth rather than sharp edges are desirable.

A method and system are disclosed for recording and displaying grazing-incidence (i.e., steep reference beam angle) holograms supported on a substrate having thin edge-illuminatable geometry. The system and process use thin edge-illuminated substrates that facilitate optimal coupling of the reference light beam at steep angles approaching grazing incidence, while maximizing the contrast of the slanted fringe structures thereof. Different recording techniques are employed when the index of refraction of the substrate is greater than that of the recording medium, than when the index of refraction of the substrate is less than that of the recording medium. A recording and playback system of complementary design is provided for recording slanted-fringe volume holograms under relaxed conditions, without compromising the light diffraction efficiency of the holograms under different playback conditions.

A light source arrangement for substantially enhaning the lighting intensity of the light beams emitted from the light source therefore includes a lens body and an illumination unit. The lens body has an illumination portion defining a light projecting surface and at least a diffraction portion defining a light diffraction surface inclinedly extended at a diffraction angle, wherein a diffraction density of the illumination portion is different from that of the diffraction portion. The illumination unit is covered by the lens body for radially generating light towards the illumination portion. When the light reaches the light diffraction surface of a diffraction portion at an angle larger than the diffraction angle, the light is substantially reflected at the light diffraction surface back towards the light projecting surface, such that the light from the illumination unit is converged to project at the light projecting surface of the lens body.

A volume-phase reflection hologram optical element is fabricated by exposing a hologram photosensitive material to two coherent light beams. One exposure light beam has an axis-asymmetric wavefront, and the other exposure light beam has focus points different in the optical axis direction (Z-direction) between on a plane (ZX-plane) including one of two directions (X- and Y-directions) mutually perpendicular on a sectional plane perpendicular to that light beam and on a plane (YZ-plane) including the other of those two directions. Thus, an image display apparatus is realized in which at the time of reproduction, the component of a predetermined wavelength of the image light diffraction-reflected by the hologram optical element is focused at positions different in the optical axis direction between on the ZX-plane and on the YZ-plane, offering different image viewing characteristics between in the X- and Y-directions.

A color sequential illumination device including in series: first and second light sources; a condenser lens; and a grating device. The grating device includes at least one Bragg grating. The condenser lens directs light from the first and second sources into the grating device at first and second incidence angles respectively. The grating device diffracts light from the first and second sources into a common direction. Desirably, the Bragg gratings are Electrically Switchable Bragg Gratings. In one embodiment the light sources are Light Emitting Diodes. Alternatively lasers may be used.

Diffractive lenses for vision correction are provided on a lens body having a first diffractive structure for splitting light into two or more diffractive orders to different focal distances or ranges, and a second diffractive structure, referred to as a multiorder diffractive (MOD) structure, for diffracting light at different wavelengths into a plurality of different diffractive orders to a common focal distance or range. In a bifocal application, the first and second diffractive structures in combination define the base power for distance vision correction and add power for near vision correction of the lens. The first and second diffractive structures may be combined on the same surface or located on different surfaces of the lens. An optical element, such as a substrate or coating, may be integrated along one or both surfaces of the lens to provide the lens with smooth outer surface(s).

A light diffusion arrangement, for a photographic device having a flashlight, includes a diffuser housing, a plurality of diffracting mesh members, and a plurality of light diffusing elements. The diffuser housing has a light-admissible surrounding sidewall radially extended from a base portion to define a light diffraction cavity. The diffracting mesh members are integrally formed on an inner side surface of the surrounding sidewall of the diffuser housing, while the light diffusing elements are integrally formed on an outer side surface of the surrounding sidewall of the diffuser housing, wherein the diffracted light is arranged to impinge on the light diffusing elements from the light diffraction cavity, in such a manner that each of the light diffusing elements is adapted to diverge the diffracted light for diffusing the diffracted light, so as to provide a uniform light diffusion effect as an optimal lighting effect for the photographic device.

A holographic waveguide LIDAR having a transmitter waveguide coupled to a beam deflector and a receiver waveguide coupled to a detector module. The transmitter waveguide contains an array of grating elements for diffracting a scanned laser beam into a predefined angular ranges. The receiver waveguide contains an array of grating elements for diffracting light reflected from external points within a predefined angular range towards the detector module.

In order to minimize light diffraction along the direction of switching and more particularly light diffraction into the acceptance cone of the collection optics, in the present invention, micromirrors are provided which are not rectangular. Also, in order to minimize the cost of the illumination optics and the size of the display unit of the present invention, the light source is placed orthogonal to the rows (or columns) of the array, and / or the light source is placed orthogonal to a side of the frame defining the active area of the array. The incident light beam, though orthogonal to the sides of the active area, is not however, orthogonal to any substantial portion of sides of the individual micromirrors in the array. Orthogonal sides cause incident light to diffract along the direction of micromirror switching, and result in light ‘leakage’ into the ‘on’ state even if the micromirror is in the ‘off’ state. This light diffraction decreases the contrast ratio of the micromirror. The micromirrors of the present invention result in an improved contrast ratio, and the arrangement of the light source to micromirror array in the present invention results in a more compact system. Another feature of the invention is the ability of the micromirrors to pivot in opposite direction to on and off positions (the on position directing light to collection optics), where the movement to the on position is greater than movement to the off position. A further feature of the invention is a package for the micromirror array, the package having a window that is not parallel to the substrate upon which the micromirrors are formed. One example of the invention includes all the above features.

Provided is a transmissive screen having low occurrence of light diffraction and moire-fringing, and also to provide a rear projector including such a high-quality transmissive screen. A transmissive screen applied to a rear projector, including a light-guide plate having substantially cylindrical light-guide spaces arranged in a flat substrate, and light-exit-angle distribution uniformizing means for making the angular distribution of the light exiting from the substantially cylindrical light-guide spaces of the light-guide plate uniform over the transmissive screen, the light-exit-angle distribution uniformizing means being provided at the light-exiting face side of the light-guide plate. A rear projector including such a transmissive screen.

A method of fabricating holographic colored contact lens is provided. A lens-making mold having multiple micro-lines on the peripheral surface is used to fabricate the contact lens and at the same time the micro-line pattern is copied onto the contact lens to form a light interference zone, which causes light waves to break up to produce light diffraction around the eyes, such that a holographic impression of a person's eyes can be created through the lenses. The perceived eyes through the lenses change color when looking from a different angle. This contact lens makes use of grating diffraction principles to impart colors on the eyes of a person wearing the contact lenses, without using any chemical colorants in the lens-making process; therefore wearing such contact lens is much healthier as opposed to a conventional colored contact lens.

A motif (30), which can have a number of parts (310, 311, 312, 313) in colours different from that of the tyre (20), is made from a diene rubber or elastomer. The external surface of the motif has a light diffraction grid created by a series of parallel micro ribs, the height of which is not more than 1 micron, while their pitch is not more than 1.5 microns. The motif (30), which can have a number of parts (310, 311, 312, 313) in colours different from that of the tyre (20), is made from a diene rubber or elastomer. The external surface of the motif has a light diffraction grid created by a series of parallel micro ribs, the height of which is not more than 1 micron, while their pitch is not more than 1.5 microns. The ribs in the different parts of the motif lie at an angle of at least 10 degrees to one another, and can be made to produce a hologram, i.e. a three-dimensional image. The material of the tyre carrying the motif contains no wax, anti-ozone or anti-oxidant agents. The motif is preferably formed by a nickel template stuck to a stainless steel support fitted in the tyre mould.

The embodiment of the invention provides a display panel and a display device, relates to the technical field of display, and can reduce the light diffraction degree of a light transmission area. Thedisplay panel comprises a display area, the display area comprises an optical component setting area, the optical component setting area comprises a shading area and a plurality of light-transmittingarea units distributed in rows and columns, and each light-transmitting area unit comprises a plurality of light-transmitting areas; each light-transmitting area unit comprises a first light-transmitting area group and a second light-transmitting area group which are arranged along a first direction, each first light-transmitting area group comprises a first light-transmitting area and a second light-transmitting area which are arranged along a second direction, and each second light-transmitting area group comprises a third light-transmitting area and a fourth light-transmitting area which are arranged along the second direction; each light-transmitting area has a length direction, and an included angle between the length direction of each light-transmitting area and the first direction ranges from 10 degrees to 40 degrees and comprises an endpoint value; and, in the light-transmitting area unit, the length direction of each light-transmitting area points to the area among the first light-transmitting area, the second light-transmitting area, the third light-transmitting area and the fourth light-transmitting area.