Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 12
Get Book Here
Book Description
High-speed (20 kHz) digital in-line holography (DIH) is applied for 3D quantification of the size and velocity of fragments formed from the impact of a single water drop onto a thin film of water and burning aluminum particles from the combustion of a solid rocket propellant. To address the depth-of-focus problem in DIH, a regression-based multiframe tracking algorithm is employed, and out-of-plane experimental displacement accuracy is shown to be improved by an order-of-magnitude. Comparison of the results with previous DIH measurements using low-speed recording shows improved positional accuracy with the added advantage of detailed resolution of transient dynamics from single experimental realizations. Furthermore, the method is shown to be particularly advantageous for quantification of particle mass flow rates. For the investigated particle fields, the mass flows rates, which have been automatically measured from single experimental realizations, are found to be within 8% of the expected values.
Author: Liangcai Cao
Publisher: Frontiers Media SA
ISBN: 2832506178
Category : Science
Languages : en
Pages : 147
Get Book Here
Book Description
Author: Pascal Picart
Publisher: John Wiley & Sons
ISBN: 1119091926
Category : Technology & Engineering
Languages : en
Pages : 318
Get Book Here
Book Description
A state of the art presentation of important advances in the field of digital holography, detailing advances related to fundamentals of digital holography, in-line holography applied to fluid mechanics, digital color holography, digital holographic microscopy, infrared holography, special techniques in full field vibrometry and inverse problems in digital holography
Author: Anand Asundi
Publisher: John Wiley & Sons
ISBN: 1119972787
Category : Technology & Engineering
Languages : en
Pages : 189
Get Book Here
Book Description
Approaching the topic of digital holography from the practical perspective of industrial inspection, Digital Holography for MEMS and Microsystem Metrology describes the process of digital holography and its growing applications for MEMS characterization, residual stress measurement, design and evaluation, and device testing and inspection. Asundi also provides a thorough theoretical grounding that enables the reader to understand basic concepts and thus identify areas where this technique can be adopted. This combination of both practical and theoretical approach will ensure the book's relevance and appeal to both researchers and engineers keen to evaluate the potential of digital holography for integration into their existing machines and processes. Addresses particle characterization where digital holography has proven capability for dynamic measurement of particles in 3D for sizing and shape characterization, with applications in microfluidics as well as crystallization and aerosol detection studies. Discusses digital reflection holography, digital transmission holography, digital in-line holography, and digital holographic tomography and applications. Covers other applications including micro-optical and diffractive optical systems and the testing of these components, and bio-imaging.
Author: Ting-Chung Poon
Publisher: Cambridge University Press
ISBN: 1107729114
Category : Science
Languages : en
Pages : 227
Get Book Here
Book Description
Get up to speed with digital holography with this concise and straightforward introduction to modern techniques and conventions. Building up from the basic principles of optics, this book describes key techniques in digital holography, such as phase-shifting holography, low-coherence holography, diffraction tomographic holography and optical scanning holography, discussing their practical applications, and accompanied by all the theory necessary to understand the underlying principles at work. A further chapter covers advanced techniques for producing computer-generated holograms. Extensive Matlab code is integrated with the text throughout and available for download online, illustrating both theoretical results and practical considerations such as aliasing, zero padding and sampling. Accompanied by end-of-chapter problems and an online solutions manual for instructors, this is an indispensable resource for students, researchers and engineers in the fields of optical image processing and digital holography.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 18
Get Book Here
Book Description
Digital in-line holography and plenoptic photography are two techniques for single-shot, volumetric measurement of 3D particle fields. Here we present a preliminary comparison of the two methods by applying plenoptic imaging to experimental configurations that have been previously investigated with digital in-line holography. These experiments include the tracking of secondary droplets from the impact of a water drop on a thin film of water and tracking of pellets from a shotgun. Both plenoptic imaging and digital in-line holography successfully quantify the 3D nature of these particle fields. This includes measurement of the 3D particle position, individual particle sizes, and three-component velocity vectors. For the initial processing methods presented here, both techniques give out-of-plane positional accuracy of approximately 1-2 particle diameters. For a fixed image sensor, digital holography achieves higher effective in-plane spatial resolutions. However, collimated and coherent illumination makes holography susceptible to image distortion through index of refraction gradients, as demonstrated in the shotgun experiments. On the other hand, plenotpic imaging allows for a simpler experimental configuration. Furthermore, due to the use of diffuse, white-light illumination, plenoptic imaging is less susceptible to image distortion in the shotgun experiments. Additional work is needed to better quantify sources of uncertainty, particularly in the plenoptic experiments, as well as develop data processing methodologies optimized for the plenoptic measurement.
Author: Ulf Schnars
Publisher: Springer
ISBN: 3662446936
Category : Technology & Engineering
Languages : en
Pages : 233
Get Book Here
Book Description
This highly practical and self-contained guidebook explains the principles and major applications of digital hologram recording and numerical reconstruction (Digital Holography). A special chapter is designated to digital holographic interferometry with applications in deformation and shape measurement and refractive index determination. Applications in imaging and microscopy are also described. Spcial techniques such as digital light-in-flight holography, holographic endoscopy, information encrypting, comparative holography, and related techniques of speckle metrology are also treated
Author: Ulf Schnars
Publisher: Springer Science & Business Media
ISBN: 3540269118
Category : Science
Languages : en
Pages : 165
Get Book Here
Book Description
This highly practical and self-contained guidebook explains the principles and major applications of digital hologram recording and numerical reconstruction (Digital Holography). A special chapter is designated to digital holographic interferometry with applications in deformation and shape measurement and refractive index determination. Applications in imaging and microscopy are also described. Spcial techniques such as digital light-in-flight holography, holographic endoscopy, information encrypting, comparative holography, and related techniques of speckle metrology are also treated
Author: Pascal Picart
Publisher: John Wiley & Sons
ISBN: 1118563204
Category : Computers
Languages : en
Pages : 274
Get Book Here
Book Description
This book presents a substantial description of the principles and applications of digital holography. The first part of the book deals with mathematical basics and the linear filtering theory necessary to approach the topic. The next part describes the fundamentals of diffraction theory and exhaustively details the numerical computation of diffracted fields using FFT algorithms. A thorough presentation of the principles of holography and digital holography, including digital color holography, is proposed in the third part. A special section is devoted to the algorithms and methods for the numerical reconstruction of holograms. There is also a chapter devoted to digital holographic interferometry with applications in holographic microscopy, quantitative phase contrast imaging, multidimensional deformation investigations, surface shape measurements, fluid mechanics, refractive index investigations, synthetic aperture imaging and information encrypting. Keys so as to understand the differences between digital holography and speckle interferometry and examples of software for hologram reconstructions are also treated in brief. Contents 1. Mathematical Prerequisites. 2. The Scalar Theory of Diffraction. 3. Calculating Diffraction by Fast Fourier Transform. 4. Fundamentals of Holography. 5. Digital Off-Axis Fresnel Holography. 6. Reconstructing Wavefronts Propagated through an Optical System. 7. Digital Holographic Interferometry and Its Applications. Appendix. Examples of Digital Hologram Reconstruction Programs
Author: Леонид Пинхусович Ярославский
Publisher: Springer
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 192
Get Book Here
Book Description
Synthesis of holograms; Wavefront analysis and simulation; Hardware and software.
