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Engineering student writers must document their reference sources in their theses, papers, proposals, reports, and related documents that they prepare. This is generally done in Microsoft Word or in a LaTeX software package and typically done in the IEEE citation style which is widely used in engineering and technology. In this work, we identify 25 primary reference types and 21 secondary reference types that are used in present-day engineering writing. Because all 46 of these engineering reference types are typically not available in commercial reference management software, we have generated customization files for the widely used EndNote reference management software package that enable referencing to be done using either Cite-While-You-Write (CWYW) for Word users or using BibTeX for LaTeX users. These customization files and instructions on how to install and use them, herein called the Georgia Tech Engineering Reference Management System (GTERMS), are made available on an open-access free-to-use basis. 

Quantitative phase imaging (QPI) is an invaluable microscopic technology for definitively imaging phase objects such as biological cells and optical fibers. Traditionally, the condenser lens in QPI produces disk illumination of the object. However, it has been realized by numerous investigators that annular illumination can produce higher-resolution images. Although this performance improvement is impressive and well documented, the evidence presented has invariably been qualitative in nature. Recently, a theoretical basis for annular illumination was presented by Baoet al.[Appl. Opt.58,137(2019)APOPAI0003-693510.1364/AO.58.000137]. In our current work, systematic experimental QPI measurements are made with a reference phase mask to rigorously document the performance of annular illumination. In both theory and experiment, three spatial-frequency regions are identified: low, mid, and high. The low spatial-frequency region response is very similar for disk and annular illumination, both theoretically and experimentally. Theoretically, the high spatial-frequency region response is predicted to be much better for the annular illumination compared to the disk illumination––and is experimentally confirmed. In addition, the mid-spatial-frequency region response is theoretically predicted to be less for annular illumination than for disk illumination. This theoretical degradation of the mid-spatial-frequency region is only slightly experimentally observed. This bonus, although not well understood, further elevates the performance of annular illumination over disk illumination. 

Searching, compiling, understanding, and explaining the literature relative to one’s research or project represents an essential 21-st century skill for students. The innovation in the present work is that the full range of these diverse topics can be integrated and team taught, in a single unified course format. There is widespread awareness that the rapid advances in technology have greatly accelerated fundamental progress in science, engineering, and medicine as well as in the entrepreneurial development in these fields. Simultaneously, there have been, perhaps less publicized, advances in information science, database technology, literature searching tools, data compilation tools, and data sharing tools. To be competitive, students need to learn about and to incorporate these powerful tools into their research and engineering project work while they are in school and after graduation. Lessons learned in developing a productive academic research laboratory (Optics Laboratory at Georgia Tech) were used to formulate an inclusive suite of the needed topics and to introduce these via a course for undergraduate students to be team taught by an engineering professor and several librarians. After five offerings, this course has earned permanent listing. The resulting 2-credit hour elective “Research Methods” course has gotten high course evaluations. The course has enrolled not only the intended undergraduate students, but also has attracted graduate students, post-doctoral researchers, and faculty as well. 

Tomographic deconvolution phase microscopy (TDPM) is a promising approach for 3D quantitative imaging of phase objects such as biological cells and optical fibers. In the present work, the alternating direction method of multipliers (ADMM) is applied to TDPM to shorten its image acquisition and processing times while simultaneously improving its accuracy. ADMM-TDPM is used to optimize the image fidelity by minimizing Gaussian noise and by using total variation regularization with the constraints of nonnegativity and known zeros. ADMM-TDPM can reconstruct phase objects that are shift variant in three spatial dimensions. ADMM-TDPM achieves speedups of 5x in image acquisition time and greater than 10x in image processing time with accompanying higher accuracy compared to TDPM. 

The imaging performance of tomographic deconvolution phase microscopy can be described in terms of the phase optical transfer function (POTF) which, in turn, depends on the illumination profile. To facilitate the optimization of the illumination profile, an analytical calculation method based on polynomial fitting is developed to describe the POTF for general nonuniform axially symmetric illumination. This is then applied to Gaussian and related profiles. Compared to numerical integration methods that integrate over a series of annuli, the present analytical method is much faster and is equally accurate. Further, a “balanced distribution” criterion for the POTF and a least-squares minimization are presented to optimize the uniformity of the POTF. An optimum general profile is found analytically by relaxed optimal search, and an optimum Gaussian profile is found through a tree search. Numerical simulations confirm the performance of these optimum profiles and support the balanced distribution criterion introduced. 

Three-dimensional quantitative phase imaging (3D QPI) is widely recognized as a potentially high-impact microscopic modality. Central to determining the resolution capability of 3D QPI is the phase optical transfer function (POTF). The magnitude of the POTF over its spatial frequency coverage (SFC) specifies the intensity of the response for each allowed spatial frequency. In this paper, a detailed analysis of the POTF for an axially symmetric optical configuration is presented. First, a useful geometric interpretation of the SFC, which enables its visualization, is presented. Second, a closed-form 1D integral expression is derived for the POTF in the general nonparaxial case, which enables rapid calculation of the POTF. Third, this formulation is applied to disk, annular, multi-annuli, and Gaussian illuminations as well as to an annular objective. Taken together, these contributions enable the visualization and simplified calculation of the 3D axially symmetric POTF and provide a basis for optimizing QPI in a wide range of applications. 

Unexpected micrometer-scale patterns in the induced refractive index of various commercial fiber Bragg gratings (FBGs) are observed in the cross-sectional fiber directions, which are in addition to the expected periodic variations along the fiber axis. These measurements were made using 3D tomographic deconvolution phase microscopy, a type of quantitative phase imaging. The cross-sectional patterns observed are shown to exhibit a variety of appearances, including fringes normal to the fiber axis and radial blades, the details apparently depending on the FBG writing method.