Design of a high-resolution holographic waveguide eye-tracking system operating in near-infrared with conventional optical elements.

The eye-tracking system plays an essential role in the augmented reality (AR) eyewear. Waveguide volume holographic optical elements (HOE) that can be made with high efficiency, thin form, and lightweight are well-suited for this application. Traditional holographic lenses formed with spherical wavefronts at visible wavelengths and used for near-infrared (NIR) eye-tracking systems suffer from significant image aberrations, image tilt, and ghost images.

High energy yield bifacial spectrum-splitting photovoltaic system.

In this paper a photovoltaic system is proposed that achieves high energy yield by integrating bifacial silicon cells into a spectrum-splitting module. Spectrum splitting is accomplished using volume holographic optical elements to spectrally divide sunlight onto an array of photovoltaic cells with different bandgap energies. Light that is reflected from the ground surface onto the rear side of the module is converted by the bifacial silicon cells.

Volume hologram replication system for spectrum-splitting photovoltaic applications.

A system for replicating high-efficiency volume hologram arrays, which has potential for high-volume manufacturing, is proposed. The system can meet the fabrication requirements of spectrum-splitting photovoltaic systems that are based on transmission volume holographic lens arrays. While previous hologram replication systems are mostly based on variations of the contact-copy method, the new technique is based on diffraction of reference and object beams from a master hologram through a prism and does not require contact with the copy hologram.

Wavelength-coded volume holographic imaging endoscope for multidepth imaging.

A wavelength-coded volume holographic imaging (WC-VHI) endoscope system capable of simultaneous multifocal imaging is presented. The system images light from two depths separated by 100  μm in a tissue sample by using axial chromatic dispersion of a gradient index probe in combination with two light-emitting diode sources and a multiplexed volume hologram to separate the images. This system is different from previous VHI systems in that it uses planar multiplexed gratings and does not require curved holographic gratings.

Volume holographic imaging endoscopic design and construction techniques.

A reflectance volume holographic imaging (VHI) endoscope has been designed for simultaneous in vivo imaging of surface and subsurface tissue structures. Prior utilization of VHI systems has been limited to ex vivo tissue imaging. The VHI system presented in this work is designed for laparoscopic use.