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We propose augmented reality (AR) near-eye display using a holographically printed freeform mirror array. A wide depth of field AR system is implemented by the retinal projection via a small mirror array. Since we use a holographic mirror array, more advantages over a traditional physical mirror array are achieved. Due to the see-through characteristics of the holographic optical element (HOE), the array structure does not obstruct the sight of an observer. Also, the holographic printing technique for the freeform mirror array enables a wide depth of field system without using a floating lens and compensates for the astigmatism of the HOE. The detailed design method of the freeform mirror array HOE is presented. Through the retinal image simulations and the experimental results, the feasibility of the proposed method is verified.

A compact augmented reality (AR) combiner using Pancharatnam-Berry phase (PBP) lens and holographic optical element (HOE) is proposed. PBP lens is activated as a convex lens or a concave lens according to the polarization state of the input light wave. By using this characteristic, a thin AR eyepiece with a large numerical aperture (NA) is constructed. The AR eyepiece operates as a convex lens for the input light with a right-handed circular polarization state and operates as a transparent plate for the left-handed circularly polarized light. In order to adopt this AR eyepiece to the AR combiner, a chromatic aberration should be compensated. To resolve the chromatic aberration, HOE which diffracts the light rays with different profiles according to the input wavelength is designed. By combining this HOE with the AR eyepiece and a light guide, a compact AR combiner providing a wide field of view (FOV) is designed. A prototype of the proposed AR combiner is presented along with experimental results and analysis.

The use of Holographic or Diffractive optics is on the rise, premium DSLR optics using this technology is an outstanding example of compact device. This technology applied to head-up display (HUD) is presented, using the windshield as a transparent holographic display, with the ability to present floating graphical object in a large field of view. Augmented Reality display will be possible, increasing considerably the User Experience and situational awareness. Additionally, the use of Holographic Optical Element reduces the size, weight and cost of the actual HUD box.

Light trapping is a useful approach for increasing the absorption of thin film photovoltaic (PV) cells. Simple light trapping can be achieved by incorporating a scattering layer on the top and bottom surface of cells and can increase absorption by a factor of 4n2. Recently, ultralight trapping using Rugate and 1-D photonic bandgap filters have been proposed to increase light trapping by a factor of 4n2 /sin2θ, where θ is half of the acceptance angle. In this paper, we present the design of a holographic ultralight trapping filter. The holographic filter can be implemented in large areas at a low cost, which makes it scalable for PV applications. A design is presented that increases the optical path length for near bandgap wavelengths in a thin-film silicon PV cell. The optical path length enhancement is converted to electrical output using the PC-1D simulation software. The short-circuit current for a 10-µm-thick silicon PV cell increases by nearly 14.7% relative to a cell without light trapping.

A small-form-factor (SFF) blue-light optical pickup head (OPH) with holographic optical element (HOE) has been fabricated and assembled. The assembly and alignment of various components in the pickup head were facilitated by using a flip chip bonder. Experimental results indicated that the focusing error signal (FES) of the assembled OPH with the wavelength of 405 nm could be successfully detected. The linear range of the FES was about than 4 μm. The gauge repeatability and reproducibility (GR&R) of the assembly process was tested and found to be acceptable.

A small-form-factor (SFF) pickup head with a holographic optical element (HOE) is fabricated. The system employs a finite-conjugate object lens to focus a light beam. A holographic optical element is used to simplify the optical configuration. It provides a better means of alignment of fabrication and reduces the size of system relative to reflective light route. Thermal analysis was utilized to prove that temperature of LD is under an acceptable range. The pickup head system based on discrete components and a flip chip bonder with highly accurate alignment was to integrate it. Focusing error signal (FES) of pickup head was measured and presented. The optical system is demonstrated and proved that it is a feasible system.

For the purpose of backward compatibility to the CD and DVD specifications, the optical pickup head (OPH) design with multiple laser wavelengths and numerical apertures (NAs) is necessary for the Blu-ray Disc (BD) system. By utilizing the features of an integrated optical unit (IOU) and a holographic optical element (HOE), this study presents a novel three-wavelength BD OPH configuration with compactness in a single optical path. There are two OPH designs with the astigmatic and knife-edge focusing detection methods applied to the IOU configurations in this paper, respectively. The simulation results are satisfactory and show the feasibility of the designs.

This paper presents the design and fabrication of a small-form-factor optical pickup head (OPH) for both red and blue wavelength. A holographic optical element (HOE) is used for beam splitting, aberration correction, and servo-signal generation to reduce the number of components and simplify the assembly procedure. In addition to demonstrating this OPH by using existing discrete components, several key components and processes are developed to use micro-electro-mechanical system (MEMS) technology to facilitate batch fabrication and wafer level assembly of the micro OPU.

With proper system design, infrared multispot diffusing (MSD) configuration communications links promise several orders of magnitude higher bit rates than radio links. Essential to the communications system are the optical subsystems: transmitter and receiver optics. Preliminary experiments on fabrication of beamshaping optical elements for the transmitter and receiver optical front-end have been conducted. The impact of optical subsystems on channel characteristics is investigated, and the results undoubtedly prove the great potential of MSDC. Use of holographic optical elements at both transmitter and receiver increases the signal-to-noise ratio by at least 11 dB and at the same time significantly improves the power budget of the system by reducing path loss by more than 6 dB.

This paper addresses one of the most promising candidates for high-speed in-house wireless communications, namely, the multi-spot diffusing configuration (MSDC). Since it uses the optical infrared medium for data transmission, it has the inherent potential for achieving very high capacities. The channel characteristics in MSDC are simulated and the causes for channel distortion are analyzed. Then, conditions for creation of a virtually ideal channel are derived. It is shown that the 3-dB channel bandwidth can be extended up to beyond 2 GHz. This bandwidth comes at the cost of a poor power efficiency. In order to compensate for that, a novel receiver optical front-end design is proposed and its performance is analyzed. Taking advantage of the unique properties of the holographic optical elements, the conventional optical front-end, consisting of a concentrator and a filter, is replaced by a single holographic curved mirror. The utilization of such a holographic optical element improves the signal-to-shot noise ratio by up to 18.5 dB.

The optical configuration proposed by Optware Corporation has the features of recording the holographic versatile disk (HVD) and backwardly retrieving CD and DVD. This paper presents a novel design that applies the technology of integrated optical unit to the HVD system. This unit comprises a holographic optical element for splitting light and generating servo signal. A transmissive spatial light modulator (SLM) with central data part and outer-ring reference part is adopted for modulating the laser beams. A new outer-ring polarizer is accompanied with the SLM. Two lasers, one with 532 nm for the HVD and the other with 650 nm for the CD/DVD, are included in the unit. Analysis for the system was performed. Simulation results show the feasibility for implementing an integrated collinear holographic system with miniaturized size

The CD-ROM and CD-R (recordable CD) playback compatibility is in great demand for DVD-ROM disc drive devices. The authors developed a new optical mechanism that utilizes a holographic optical element with wavelength selectivity, and two-wavelength two-beam laser in order to produce a DVD/CD/CD-R playback compatible pick-up with one objective lens.

An optical head composed of an optical module and a biaxial actuator is designed for small form factor drives. This system adopts a finite-conjugate objective lens with numerical aperture 0.65 for 654-nm wavelength. A holographic optical element is used for simplifying the optical configuration which provides a better approach for alignment. The actuator is of a spider-like suspension for the focusing and is of a swing arm for the tracking.

We have developed a novel stacked silicon-based microoptical system, which is optical-on-axis and transmissible in both visible and infrared ranges. By using the new microoptical system techniques, we fabricated a miniaturized optical pickup head module. This optical pickup head consisted of a 650-nm laser diode, a 45/spl deg/ silicon reflector, a grating, a holographic optical element, and some aspherical Fresnel lenses. These optical phase elements fabricated on a SiN/sub x/ membrane were suspended on Si chips. Each element was then stacked by chip bonding. We could obtain a circular focusing spot on the optical disc as small as 3.1 /spl mu/m.

A parallel digital optical cellular image processor (DOCIP) functionally comprises an array of identical I-bit processing elements or cells, a fixed interconnection network, and a control unit. Four interconnection network topologies are described, and include two variants of a mesh-connected array and two variants of a cellular hypercube network. The instruction sets of these single-instruction multiple-data (SIMD) machines are based on a mathematical morphological theory, binary image algebra (BIA), which provide an inherently parallel programming structure for their control. Physically, a DOCIP architecture uses a holographic optical element in a 3D free-space optical system to implement off-chip interconnections, and an optoelectronic spatial light modulator to implement a 2D array of nonlinear processing elements and (optionally) local on-chip interconnections. Two examples are given. The first, an experimental implementation of a single 54-gate cell of the DOCIP, uses an optically recorded hologram for within-cell optical interconnections, and a spatial light modulator for a 2D array of optically accessible gates. The second, a design for an efficient and more manufacturable architecture, uses a computer-generated diffractive optical element for cell-to-cell interconnections, and a 20 smart-pixel array of DOCIP cells, each cell having electronic logic and optical input/output. >

This paper reports on the progress in implementing optical interconnections for VLSI. Four areas are covered: 1) the holographic optical element (HOE), 2) the laser sources, 3) the detectors and associated circuits forming an optically addressed gate, and 4) interconnection experiments in which five gates are actuated from one source. A laser scanner system with a resolution of 12 µm × 20 µm has been utilized to generate the HOE's. Diffraction efficiency of the HOE and diffracted spot size have been measured. Stock lasers have been modified with a high-frequency package for interconnect experiments, and buried heterostructure fabrication techniques have been pursued. Measurements have been made on the fabricated photodetectors to determine dark current, responsivity and response time. The optical gates and the overall chip have been driven successfully with an input light beam, as well as with the optical signal interconnected through the one to five hologram.

A set of ten experiments designed to introduce undergraduate electrical engineering students to the area of fiber optics is described. The projects include measurement of pertinent parameters of optical fibers, sources, and detectors (the major components of fiber optic systems), the construction of a simple fiber optic communication link, the use of an optical fiber as a sensor of acoustic waves, and the making of a holographic optical element to serve as a fiber coupler. Although the experiments are expressly designed for a project-type laboratory, they are also suitable for other situations such as classroom demonstrations.