Abstract: Briefly, in accordance with one or more embodiments, an optical relay comprises a partially-reflective-coated Fresnel lens or similar low-profile lens such as a diffractive lens or a holographic lens having a first index of refraction and a filler medium having a second index of refraction and being disposed adjacent to the Fresnel lens. The optical relay enables the optical power of the Fresnel or similar low-profile lens embedded within the two layers to influence a beam that is reflected from the optical relay while allowing transmitted light to experience little or no influence from the embedded lens.

Abstract: Substrate-guided relays that employ light guiding substrates to relay images from sources to viewers in optical display systems. The substrate-guided relays are comprised of an input coupler, an intermediate substrate, and an output coupler. In some embodiments, the output coupler is formed in a separate substrate that is coupled to the intermediate substrate. The output coupler may be placed in front of or behind the intermediate substrate, and may employ two or more partially reflective surfaces to couple light from the coupler. In some embodiments, the input coupler is coupled to the intermediate substrate in a manner that the optical axis of the input coupler intersects the optical axis of the intermediate substrate at a non-perpendicular angle.

Abstract: Substrate-guided relays that employ light guiding substrates to relay images from sources to viewers in optical display systems. The substrate-guided relays are comprised of an input coupler, an intermediate substrate, and an output coupler. In some embodiments, the output coupler is formed in a separate substrate that is coupled to the intermediate substrate. The output coupler may be placed in front of or behind the intermediate substrate, and may employ two or more partially reflective surfaces to couple light from the coupler. In some embodiments, the input coupler is coupled to the intermediate substrate in a manner that the optical axis of the input coupler intersects the optical axis of the intermediate substrate at a non-perpendicular angle.

Abstract: A projection system, such as a system suitable for head-up displays in automobiles, includes a laser projection source (101) and a scanner (102). Light from the laser projection source (101) is scanned across a projection surface (104), which can be a car's windshield. The projection surface (104) includes a buried numerical aperture expander (105) capable of reflecting some light and transmitting other light. The system may also include an image projection source (551) capable of presenting high-resolution images on a sub-region (552) of the projection surface (604) that has a optical relay (650) disposed therein.

Abstract: Briefly, in accordance with one or more embodiments, a birefringent layer may be utilized in conjunction with a head-up display (HUD) for a vehicle or the like, for example where the birefringent layer is disposed in or on the windshield. The birefringent layer may impart a change in the polarization of light emerging from a projector of the head-up display in order to reduce or minimize interference between beams from the display and reflecting off of two or more surfaces that are combined at the viewer's eye, and/or to reduce or minimize the effect of polarizing sunglasses on the viewability of the image projected by the display. In one or more embodiments, the birefringent layer alters the polarization of the light reaching the viewer's eye if the user is wearing polarizing glasses or lenses so that less light from the display is blocked.

Abstract: A scanned beam projection system includes a polarizing beam splitter, a polarization rotating component and a scanning mirror. Light is directed on a first light path to the polarizing beam splitter at a substantially constant angle of incidence. The P-polarized light passes through. The P-polarized light passes through the polarization rotating component, is reflected off the scanning mirror back through the polarization rotating component, and arrives at the polarizing beam splitter as S-polarized light with a non-constant angle of incidence. The S-polarized light is reflected by the polarizing beam splitter, and a scanned image results.

Abstract: Briefly, in accordance with one or more embodiments, a buried numerical aperture expander may be utilized to provide a head-up or virtual display at a larger field of view without requiring a larger amount of space, larger sized display, or larger sized optics. The buried numerical aperture expander is capable of selectively reflecting light emanating from a display such that the reflected light is expanded into a larger field of view, while simultaneously allowing other light to be transmitted through the buried numerical aperture expander without expansion so that the buried numerical aperture expander may be deployed in conjunction with a windshield or window without adversely affecting the ability to see through buried numerical aperture expander.

Abstract: An image generation apparatus provides correction for color offsets. Color offsets may be caused by misalignments in laser diodes or optics assemblies in a laser projector. The offsets may be measured during or after manufacture of the laser projector. An image buffer is responsive to the offset data to translate each color plane separately. The image buffer may include separately addressable portions for each color. Further, variable delay elements on the output of the image buffer may provide color offset correction. Interpolation provides further offset correction.

Abstract: Substrate-guided relays that employ light guiding substrates to relay images from sources to viewers in optical display systems. The substrate-guided relays are comprised of an input coupler, an intermediate substrate, and an output coupler. In some embodiments, the output coupler is formed in a separate substrate that is coupled to the intermediate substrate. The output coupler may be placed in front of or behind the intermediate substrate, and may employ two or more partially reflective surfaces to couple light from the coupler. In some embodiments, the input coupler is coupled to the intermediate substrate in a manner that the optical axis of the input coupler intersects the optical axis of the intermediate substrate at a non-perpendicular angle.

Abstract: A scanned beam display device scans a beam to paint an image. The beam is scanned in two dimensions and includes at least one sinusoidal component. Phase offsets are introduced to provide different scan trajectories for successive traversals of the image field of view.

Abstract: The invention provides a pickup head used in an optical data storage system. The pickup head contains a diffractive optical element (DOE) stack on a semiconductor substrate. The DOE stack includes multiple diffractive lenses for providing several diffractive surfaces and a middle layer serving as a beamsplitter and servo-generating element for a light reflected from an optical storage medium. The middle layer is sandwiched by the diffractive lenses that are located on both outer parts of the DOE stack. The semiconductor substrate includes at least a laser source and several photodetectors. The middle layer serving its function preferably includes a polarization-selective DOE and a quarter-wave retarder oriented to rotate a polarization state of the laser source, so that only the light reflected from the optical storage medium is diffracted by the polarization-selective DOE.

Abstract: The invention provides a pickup head used in an optical data storage system. The pickup head contains a diffractive optical element (DOE) stack on a semiconductor substrate. The DOE stack includes multiple diffractive lenses for providing several diffractive surfaces and a middle layer serving as a beamsplitter and servo-generating element for a light reflected from an optical storage medium. The middle layer is sandwiched by the diffractive lenses that are located on both outer parts of the DOE stack. The semiconductor substrate includes at least a laser source and several photodetectors. The middle layer serving its function preferably includes a polarization-selective DOE and a quarter-wave retarder oriented to rotate a polarization state of the laser source, so that only the light reflected from the optical storage medium is diffracted by the polarization-selective DOE.

Abstract: A focus/tracking method and system is provided for use in an optical drive with a possibly multiple-wavelength laser source for control of the focus/tracking of the pickup head of the optical drive. The use of a multiple-wavelength laser source allows the optical drive to read data from various types of optical discs. The focus/tracking method and system combines the use of a differential, dual optical channel method for focusing control of the laser beam used to read data from the optical disc and the use of the single-beam tracking method for tracking control of the same. The focus error signal and the tracking error signal can be obtained from the same set of multi-element photodetectors. The structure of the system can therefore be simplified to include a reduced number of constituent components thus allowing a reduction in manufacturing cost.

Abstract: The present invention discloses a multiple-beam holographic optical pick-up head, which has the advantages of the multiple-beam optical pick-up head and the holographic optical pick-up head and can increase the light usage efficiency. This invention uses the property that a polarized diffractive optical element can generate different optical effects for laser beam with different polarizations and places a polarized multiple-beam grating and polarized hologram on the optical path for splitting the incident light toward the disc into multiple reading beams by the multiple-beam grating. The returning laser beams reflected from the disc are diffracted and diverted by the hologram to reach a photodetector. Both the incident and reflective beams are diffracted once only; thus the light usage efficiency can be increased.

Abstract: The invention provides a pickup head used in an optical data storage system. The pickup head contains a diffractive optical element (DOE) stack on a semiconductor substrate. The DOE stack includes multiple diffractive lenses for providing several diffractive surfaces and a middle layer serving as a beamsplitter and servo-generating element for a light reflected from an optical storage medium. The middle layer is sandwiched by the diffractive lenses that are located on both outer parts of the DOE stack. The semiconductor substrate includes at least a laser source and several photodetectors. The middle layer's function preferably includes a polarization-selective DOE and a quarter-wave retarder oriented to rotate a polarization state of the laser source, so that only the light reflected from the optical storage medium is diffracted by the polarization-selective DOE.

Abstract: A focus/tracking method and system is provided for use in an optical drive with a possibly multiple-wavelength laser source for control of the focus/tracking of the pickup head of the optical drive. The use of a multiple-wavelength laser source allows the optical drive to read data from various types of optical discs. The focus/tracking method and system combines the use of a differential, dual optical channel method for focusing control of the laser beam used to read data from the optical disc and the use of the single-beam tracking method for tracking control of the same. The focus error signal and the tracking error signal can be obtained from the same set of multi-element photodetectors. The structure of the system can therefore be simplified to include a reduced number of constituent components, thus allowing a reduction in manufacturing cost.

Abstract: A dual-wavelength holographic laser module is provided. The dual-wavelength holographic laser module includes a holographic optical element (HOE), a multiple-element photodetector, and a laser light source that can produce a laser light with a wavelength that has, for example, two desired quantities. The laser light emitted from the laser light source with a desired wavelength can travel through the HOE and an objective lens unit, which is used to focus the laser light onto an optical disk of the DVD system, the CD system, or the CD-R system, depending on which wavelength quantity is chosen. The objective lens unit includes a single lens with a changeable NA quantity or a two-lens system that can be switched to put one lens at a time in the optical path. The optical disk reflects the laser light back to the HOE along the same light path. The reflected laser light is diffracted by the HOE to reach to the multiple-element photodetector.

Abstract: A two-wavelength laser diode package is provided, which can be utilized in the read/write head of an optical drive capable of reading data from different types of optical discs, such as CD (compact disc), CD-R (CD Recordable) and DVD (digital versatile disc). The laser diode package includes a pair of laser diodes of two different specifications in wavelength, which are disposed on one or two submounts, either horizontally or vertically oriented with each other. Further, a beam coinciding means, such as a micro dichroic prism, a micro dichroic plate, a micro dichroic beam-splitter, or an external dichroic beam-splitter, is used to make the two respective laser beams from the two laser diodes to propagate on the same propagation axis when in use.

Abstract: An optical pickup device including a lighting source, a condensing apparatus, a diffracting means, and a light detector. The light source generates and emits a light beam to the diffracting means. The diffracting means includes a center region and an outer region which encloses the center region. As the light travels from the light source towards the optical storage medium the main zero-order beam which reads the information on the disk encounters only the center region of the diffracting means while the two sub-beams used for track following are created as +1 and -1 diffraction orders from the outer region of the diffracting means. The three beams reflected from the recording medium all pass through the center region of the diffracting means and are diffracted in the direction of the detector therefrom.

Abstract: A pickup head for use in optical disk systems such as compact disk players or CD-ROM computer memory includes a holographic optical element that has two decision regions that greatly simplify the design of the pickup head. The two decision regions diffract light that encounters the holographic optical element in two different directions, respectively. The amount of light power incident upon each decision region is utilized to determine a focus error signal and to interpret information stored on the compact or optical disk.