Diffractive optics such as holographic optical elements (HOEs) can provide transparent and narrow band components with arbitrary incident and diffracted angles for near-to-eye commercial electronic products for augmented reality (AR), virtual reality (VR), and smart glass applications. In this paper, we will summarize the operational parameters and general optical geometries relevant for near-to-eye displays, the holographic substrates available for these applications, and their performance characteristics and ease of manufacture. We will compare the holographic substrates available in terms of fabrication, manufacturability, and end-user performance characteristics. Luminit is currently emplacing the manufacturing capacity to serve this market, and this paper will discuss the capabilities and limitations of this unique facility.
QD Vision has developed Quantum Dot Light Emitting Devices whose emission spans the wavelength range from 1000 nm to 1.35 μm, using tunable, narrow band quantum dot emission. These devices emit sufficient power for long range-detection by a variety of systems, run at very low drive voltages, and are producible in area emitting form-factors that are very thin and light weight. Potential applications for these devices include covert illumination, tagging, display backlighting, and line-of-sight communications.
In this paper, we demonstrate electrically driven quantum dot light emitting devices that emit in the wavelength range of 1000 nm to 1.35 μm, with full-widths at half-maximum as low as 128 nm. The devices discussed are characterized with respect to their efficiency, power output, and lifetime, and this data is used to evaluate their suitability for use in a variety of defense-related applications. Example devices are discussed, including completed prototypes 1.5mm thick with active areas up to 4 cm2. Experimental results are presented that demonstrate a low turn-on voltage of 1.4 V, a maximum external quantum efficiency of 2.5 %, a power efficiency of 25 mW/W, and a peak radiance of 18.3 W/sr.m2. Lifetimes of more than 1000 hours at operating drive levels are also shown.
Creation of patterned, efficient, and saturated color hybrid organic/inorganic quantum dot light emitting devices (QD-LEDs) is dependent on development of integrated fabrication and patterning methods for the QD layer. We show that micro-contact printing can be applied to QD deposition, generating micron-scale pattern definition, needed in pixilated-display applications. We demonstrate saturated color QD-LEDs with external quantum efficiencies in excess of 1%. Combining this technique with the use of wide optical band gap host materials, and a new synthetic route for the creation of blue emitting (CdS)ZnS nanocrystals, it is now possible to fabricate QD-LEDs with saturated color emission in the red, green and blue regions of the spectrum.
Projected shape of objects is a significant cue in fast and robust selection of images in response to visual content queries. Yet, existing methods for indexing into digital image libraries do not take full advantage of shape, primarily because this ultimately involves fundamentally difficult vision problems such as segmentation and recognition. These problems are difficult because realistic images depict objects in occlusion relationship, boundaries of objects are not clearly defined and often become ambiguous among spurious boundaries, boundaries change relative orientation in articulated objects, etc. We present a symmetry- based and contour-based representation of shape, (ii) a propagation-based method to extract partial symmetries from real images, (iii) transforms to augment this representation with that of its 'neighboring' shapes, (iv) the generation of user-sketched queries using intuitive shape deformations, and (v) multistage inexact graph-matching to extract and rank images containing objects similar to the user-defined query.