Capture, processing, and display of real-world 3D objects using digital holography

"Digital holography for 3D and 4D real-world objects' capture, processing, and display" (acronym "Real 3D") is a research project funded under the Information and Communication Technologies theme of the European Commission's Seventh Framework Programme, and brings together nine participants from academia and industry (see www.digitalholography.eu).This three-year project marks the beginning a long-term effort to facilitate the entry of a new technology (digital holography) into the three-dimensional capture and display markets. Its progress at the end of year 2 is summarised

Processing of optically-captured digital holograms for three-dimensional display

In digital holography, holograms are usually optically captured and then two-dimensional slices of the reconstruction volume are reconstructed by computer and displayed on a two-dimensional display. When the recording is of a three-dimensional scene then such two-dimensional display becomes restrictive. We outline our progress on capturing larger ranges of perspectives of three-dimensional scenes, and our progress on four approaches to better visualise this three-dimensional information encoded in the digital holograms. The research has been performed within a European Commission funded research project dedicated the capture, processing, transmission, and display of real-world 3D and 4D scenes using digital holography

3D perception of numerical hologram reconstructions enhanced by motion and stereo

We investigated the question of how the perception of 3D information of digital holograms reconstructed numerically and presented on conventional displays depends on motion and stereoscopic presentation. Perceived depth in an adjustable random pattern stereogram was matched to the depth in holographic objects. The objects in holograms were a microscopic biological cell and a macroscopic coil. Stereoscopic presentation increased perceived depth substantially in comparison to non-stereoscopic presentation. When stereoscopic cues were weak or absent e.g. because of blur, motion increased perceived depth considerably. However, when stereoscopic cues were strong, the effect of motion was small. In conclusion, for the maximisation of perceived 3D information of holograms on conventional displays, it seems highly beneficial to use the combination of motion and stereoscopic presentation

Visual perception of digital holograms on autostereoscopic displays

In digital holography we often capture optically a 3D scene and reconstruct the perspectives numerically. The reconstructions are routinely in the form of a 2D image slice, an extended focus image, or a depth map from a single perspective. These are fundamentally 2D (or at most 2.5D) representations and for some scenes are not certain to give the human viewer a clear perception of the 3D features encoded in the hologram (occlusions are not overcome, for example). As an intermediate measure towards a full-field optoelectronic display device, we propose to digitally process the holograms to allow them to be displayed on conventional autostereoscopic displays

Capture, processing, and display of real-world 3D objects using digital holography

"Digital holography for 3D and 4D real-world objects' capture, processing, and display" (acronym "Real 3D") is a research project funded under the Information and Communication Technologies theme of the European Commission's Seventh Framework Programme, and brings together nine participants from academia and industry (see www.digitalholography.eu).This three-year project marks the beginning a long-term effort to facilitate the entry of a new technology (digital holography) into the three-dimensional capture and display markets. Its progress at the end of year 2 is summarised. © 2010 IEEE

Processing of optically-captured digital holograms for three-dimensional display

In digital holography, holograms are usually optically captured and then two-dimensional slices of the reconstruction volume are reconstructed by computer and displayed on a two-dimensional display. When the recording is of a three-dimensional scene then such two-dimensional display becomes restrictive. We outline our progress on capturing larger ranges of perspectives of three-dimensional scenes, and our progress on four approaches to better visualise this three-dimensional information encoded in the digital holograms. The research has been performed within a European Commission funded research project dedicated the capture, processing, transmission, and display of real-world 3D and 4D scenes using digital holography. © 2009 SPIE

Study of optical techniques for the Ames unitary wind tunnels. Part 4: Model deformation

A survey of systems capable of model deformation measurements was conducted. The survey included stereo-cameras, scanners, and digitizers. Moire, holographic, and heterodyne interferometry techniques were also looked at. Stereo-cameras with passive or active targets are currently being deployed for model deformation measurements at NASA Ames and LaRC, Boeing, and ONERA. Scanners and digitizers are widely used in robotics, motion analysis, medicine, etc., and some of the scanner and digitizers can meet the model deformation requirements. Commercial stereo-cameras, scanners, and digitizers are being improved in accuracy, reliability, and ease of operation. A number of new systems are coming onto the market

Roadmap on optical security

Postprint (author's final draft

Optical reconstruction of transparent objects with phase-only SLMs

Three approaches for visualization of transparent micro-objects from holographic data using phase-only SLMs are described. The objects are silicon micro-lenses captured in the near infrared by means of digital holographic microscopy and a simulated weakly refracting 3D object with size in the micrometer range. In the first method, profilometric/tomographic data are retrieved from captured holograms and converted into a 3D point cloud which allows for computer generation of multi-view phase holograms using Rayleigh-Sommerfeld formulation. In the second method, the microlens is computationally placed in front of a textured object to simulate the image of the textured data as seen through the lens. In the third method, direct optical reconstruction of the micrometer object through a digital lens by modifying the phase with the Gerchberg-Saxton algorithm is achieved. © 2013 Optical Society of America