Results 161 to 170 of about 35,274,744 (211)
Some of the next articles are maybe not open access.
Subtraction digital holography
Applied Optics, 2003Overlapping of the desired (first-order) and undesired (zero-order) terms originating from the recorded primary-fringe patterns in digital holography is a problem without a real-time solution. We propose a procedure for suppressing the zero-order disturbance that is realizable in real time.
Demoli, Nazif +2 more
openaire +3 more sources
Comparative digital holography
Optics Letters, 2002We described a method for direct holographic comparison of the shape or the deformation of two objects when it is not necessary that both samples be located at the same place. In contrast to the well-known incoherent techniques based on inverse fringe projection, this new approach uses a coherent mask that is imaged onto a sample object that has a ...
Wolfgang, Osten +2 more
openaire +2 more sources
2015 IEEE 13th International Conference on Industrial Informatics (INDIN), 2015
Holographic interferometry as a means for nondestructive testing of technical or biological components has got significant momentum by the introduction of digital holography. In this paper after an introduction to holography, holographic interferometry and digital holography practical examples from deformation analysis, form determination, refractive ...
openaire +2 more sources
Holographic interferometry as a means for nondestructive testing of technical or biological components has got significant momentum by the introduction of digital holography. In this paper after an introduction to holography, holographic interferometry and digital holography practical examples from deformation analysis, form determination, refractive ...
openaire +2 more sources
Digital Holography for Security Applications
2012A survey of Digital Holography (DH) and its employment in different application fields is provided. This paper reviews the main principles of the DH focusing on the optical techniques for security purposes. Recording and processing of three dimensional data, secured storage data, the use of Multimedia Sensor Network (MSN) for encrypted data ...
Pellegrini, RM +2 more
openaire +4 more sources
Digital refocusing with incoherent holography
2014 IEEE International Conference on Computational Photography (ICCP), 2014Light field cameras allow us to digitally refocus a photograph after the time of capture. However, recording a light field requires either a significant loss in spatial resolution [11, 21, 10] or a large number of images to be captured [12]. In this paper, we propose incoherent holography for digital refocusing without loss of spatial resolution from ...
Oliver Cossairt +2 more
openaire +2 more sources
Digital in-line holography of microspheres
Applied Optics, 2002We have used digital in-line holography (DIH) with numerical reconstruction to image micrometer-sized latex spheres as well as ferrimagnetic beads suspended in gelatin. We have examined in detail theoretically and experimentally the conditions necessary to achieve submicrometer resolution of holographic reconstructions.
W, Xu +3 more
openaire +2 more sources
Annual Meeting Optical Society of America, 1988
Ordinary holograms are made by interference experiments, digital holograms by computer and plotter. The object does not have to exist physically. Most advantages of digital holograms derive from that fact. Fundamentals and some applications are reviewed: AO display; image processing; and testing.
openaire +1 more source
Ordinary holograms are made by interference experiments, digital holograms by computer and plotter. The object does not have to exist physically. Most advantages of digital holograms derive from that fact. Fundamentals and some applications are reviewed: AO display; image processing; and testing.
openaire +1 more source
Coherence requirement in digital holography
Applied Optics, 2012In this paper the coherence requirement for different holographic setups (Fresnel hologram, Fourier hologram, and image-plane hologram) is compared. This analysis is based on the investigation of the recorded interference pattern from the superposition of reference wave and object wave in in-line and off-axis mode. The outcome of this investigation can
Daniel, Claus +2 more
openaire +2 more sources
Phase-shifting digital holography
Optics Letters, 1997A new method for three-dimensional image formation is proposed in which the distribution of complex amplitude at a plane is measured by phase-shifting interferometry and then Fresnel transformed by a digital computer. The method can reconstruct an arbitrary cross section of a three-dimensional object with higher image quality and a wider viewing angle ...
I, Yamaguchi, T, Zhang
exaly +3 more sources
Aliasing error in digital holography
Applied Optics, 1976The use of the discrete Fourier transform in digital holography introduces aliasing error in the reconstructed image. Spectrum shaping to reduce dynamic range may also result in a serious increase in aliasing error. The effect of aliasing in digital holography is analyzed. It is proposed that the bandwidth be constrained when shaping the image spectrum.
J P, Allebach, N C, Gallagher, B, Liu
openaire +2 more sources