“The value of light-enabled products and services is …roughly 11 percent of the world’s economy. Accelerating photonics innovation will continue to drive economic growth and increase its share of the global GDP.”
G. M. Williams, H. Akhavan, C. Dupuy and P. Harmon, "Additive Manufacturing of Freeform Optics for Defense Applications," 2021 IEEE Research and Applications of Photonics in Defense Conference (RAPID), 2021, pp. 1-2, doi: 10.1109/RAPID51799.2021.9521386.
“An additive manufacturing platform, including nanocomposite materials and 3D printing, is presented that allows 3D-freeform gradient index (GRIN) functions to be fabricated within planar or surfaced lens elements. The degrees of design freedom allow for realization of complex optical functions that reduce optical system size and weight.”
Lippman, David H., Nicholas S. Kochan, Tianyi Yang, Greg R. Schmidt, Julie L. Bentley, and Duncan T. Moore. "Freeform gradient-index media: a new frontier in freeform optics." Optics Express 29, no. 22 (2021): 36997-37012.
“Here a new frontier in freeform optics is surveyed in the form of freeform gradient-index (F-GRIN) media… F-GRIN is a useful design tool that offers vast degrees of freedom and serves as an important complement to freeform surfaces in the design of advanced optical systems for both imaging and illumination.”
Maruca, Stephanie, et al. "Generation and propagation of Airy beams and one inch diameter focusing optics using 3D printed polymer optics." Advanced Optics for Imaging Applications: UV through LWIR VII 12103 (2022): 29-38.
“The additive manufacture of polymer optical elements has the promise of reducing component weight, providing new design capabilities, and enhanced performance for a wide variety of military and commercial optical systems. This paper reviews progress in the development of 3d printed Gradient Index (GRIN) lenses and optical phase masks.”
S. D. Campbell, D. E. Brocker, D. H. Werner, C. Dupuy, S. -K. Park and P. Harmon, "Three-dimensional gradient-index optics via injketaided additive manufacturing techniques," 2015 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, 2015, pp. 605-606, doi: 10.1109/APS.2015.7304689.
“The ability to correct for monochromatic aberrations without the need for complex geometry has made gradient-index optics an attractive area of research, but manufacturing challenges have limited their application to a select few areas. In this study, a novel method for fabricating gradient-index lenses using inkjet solid free form three-dimensional printed optical polymers is proposed.”
David H. Lippman, Rongze Xu, Greg R. Schmidt, "Freeform gradient-index optics for prescribed illumination," Proc. SPIE 12220, Nonimaging Optics: Efficient Design for Illumination and Solar Concentration XVIII, 1222005 (3 October 2022); https://doi.org/10.1117/12.2641187
“A new type of prescribed illumination optic is presented that leverages newly available freeform gradient-index (F-GRIN) media. Using F-GRIN to impart freeform optical influence, only plane-parallel surfaces are required, and by additive manufacturing, designs can directly incorporate gradient discontinuities…Fabricated designs are presented for the first time, verifying that F-GRIN optics present a flexible, new way of generating a prescribed illumination distribution.”
Stephanie Maruca, Evan Jones, Austin Granmoe, Mitch Wlodawski, Tyler Fenske, Muhammed Kamal, David Dantsker, Damien Marianucci, George Fischer, Charles Dupuy, Hooman Akhavan, Samuel Peter Grimm, and Frederick Long "Generation and propagation of Airy beams and one inch diameter focusing optics using 3D printed polymer optics", Proc. SPIE 12219, Polymer Optics and Molded Glass Optics: Design, Fabrication, and Materials 2022, 122190A (4 October 2022); https://doi.org/10.1117/12.2641348
“The additive manufacture of polymer optical elements has the promise of reducing component weight, providing new design capabilities, and enhanced performance for a wide variety of military and commercial optical systems. This paper reviews progress in the development of 3d printed Gradient Index (GRIN) lenses and optical phase masks. The 3d printing process uses a modified commercial inkjet printer and UV curable polymers that have specific nanoparticles added to them to modulate the index of refraction.”
Tianyi Yang, Freeform Gradient-Index Optics with Applications in Rotationally Variant Systems, University of Rochester ProQuest Dissertations Publishing, 2022. 29062821.
“…the newly developed rotationally variant GRIN profiles (freeform GRIN profiles) open up a new design space and can be applied in such systems…This thesis develops a set of 3D orthogonal basis polynomials (the F-GRIN basis) that can represent generalized freeform GRIN profiles. The aberrations of the F-GRIN basis are analyzed, and a design methodology to add freeform GRIN profiles in rotationally variant systems is summarized.”
Hanjra, Prayant P.S., "Analysis of Space to Ground LADAR Performance with Non-Traditional Optics" (2021). Theses and Dissertations. 5078.
“Two major obstacles to space-based LADAR systems are low power returns from targets and limitations on size and weight for transporting large optics into orbit. Signals incur significant losses during roundtrip propagation through the atmosphere and from diffuse scattering off of targets…However, to get desired performance, these optics quickly become prohibitively large and heavy to transport in a satellite. Many non-traditional optics have emerged in recent years that show promise for providing lightweight and volume constrained solutions polymer-based, gradient index (GRIN) optics.”
David H. Lippman, Robert Chou, Ankur X. Desai, Nicholas S. Kochan, Tianyi Yang, Greg R. Schmidt, Julie L. Bentley, and Duncan T. Moore, "Polychromatic annular folded lenses using freeform gradient-index optics," Applied Optics 61, A1-A9 (2022)
“The annular folded lens (AFL) is a design form offering large aperture, high-resolution imaging in a very axially compact package. The folded optic can be made monolithic for easier fabrication and alignment, yet the introduction of refractive surfaces with a dispersive optical material gives way to chromatic aberrations… By introducing freeform gradient-index (F-GRIN) media, monolithic AFL designs can achieve higher monochromatic performance as well as provide color correction for diffraction-limited polychromatic imaging.”
Long, Frederick H., et al. "Generation and propagation of airy beams and one inch diameter focusing optics using 3D printed optics." 3D Printed Optics and Additive Photonic Manufacturing III 12135 (2022): 46-55.
“The additive manufacture of polymer optical elements has the promise of reducing component weight, providing new design capabilities, and enhanced performance for a wide variety of military and commercial optical systems…The generation and propagation of Airy beams using these polymers generated optical phase masks has been investigated and analyzed through experimentation, simulations, and comparison with recent theoretical predictions.”
Cannamela, Madeleine, Jim Stasiak, Paul Harmon, Thomas Allen, and Pallavi Dhagat. "Fabrication of magnetic polymer nanocomposites using inkjet 3D print technology," NIP & Digital Fabrication Conference, vol. 2020, no. 1, pp. 1-5. Society for Imaging Science and Technology, 2020.
“Tailored magnetic nanocomposites have applications ranging from communications technologies to medical devices. Using a novel 3D fabrication technique that combines thermal inkjet and powder bed fusion print technologies, magnetic composites were fabricated by jetting magnetic nanoparticle containing ink into a polymer powder bed and then heat fusing the ink/polymer matrix.”
Andrew Kirk, Johann Veras, Samantha T. Mensah, Michael Ponting, Clara Rivero-Baleine, "Nondestructive characterization of the axial refractive index of a nanolayered PMMA/SAN17 GRIN lens via Raman spectroscopy," Optical Engineering 59(11) 112603 (17 June 2020) https://doi.org/10.1117/1.OE.59.11.112603
“The Raman spectra of polymethylmethacrylate (PMMA)/SAN17 nanolayered composite material are used to retrieve the volumetric refractive index of a manufactured gradient index (GRIN) lens. A series of five PMMA/SAN17 nanolayered composite sheets with varying PMMA to SAN17 filling fraction ratios of 0/100, 25/75, 50/50, 75/25, and 100/0 were constructed to calibrate the 785-nm Raman measurement. An additive model was then used to extrapolate the volumetric refractive index profile of the fabricated GRIN lens based on PMMA/SAN17 filling fraction. A good overall agreement between the calculated and modeled GRIN profiles can be observed with an error of ±0.003.”
Kochan, Nicholas; University of Rochester ProQuest Dissertations Publishing, 2022. 29160861.
“The progressive addition lens (PAL) is an eyeglass which continuously changes optical power as the gaze of the wearer moves downwards through different viewing zones. The astigmatism must be corrected within viewing zones of the lens. Correction of this astigmatism with power addition defines the PAL design space and is limited for homogeneous PAL designs. The present work identifies the ways in which gradient index (GRIN) lenses can be implemented as PALs.”
Conkey, Don. Compressive 3D Imaging Spectrometer. No. DOE-VOXT-18800-1. Voxtel, Inc., 2019
“The goal of this work is to improve space-based visible spectrum optics for nuclear-detonation-flash sensing, using lighter high-precision diffractive optics in long-life satellites in mid-Earth orbit (MEO). Due to the precision required to achieve these objectives, innovative designs and manufacturing methods are required to benefit nuclear detonation detection (NDD) and commercial applications with similar signal-discrimination requirements. To address this need, in this Phase I SBIR effort, optical devices were created, per plan, to enhance and discriminate signals of interest from other background emitters. Diffractive freeform gradient-index (GRIN) optical designs, materials, and parts were developed using Voxtel’s Volumetric Index of Refraction Gradient Optics (VIRGO) process to implement and demonstrate the ability to create complex higher-order polynomial optical functions.”
Teichman, Jeremy, Jenny Holzer, Bohdan Balko, Brent Fisher, and Leonard Buckley. “Gradient index optics at DARPA,” Institute for Defense Analyses, Alexandria VA, 2013.
“The Defense Advanced Research Projects Agency DARPA is interested in developing optical materials and related technologies to meet the challenge of cost-effective, reproducible, large-scale manufacturing. Modern optical systems have many individual lens elements and are often complex, bulky, and heavy. In 2002, DARPA initiated the Bio-Optic Synthetic Systems BOSS program, which was aimed at simplifying complex optical sensors. The goal of the program was to understand and synthesize the components of a biologically inspired vision system that would demonstrate a level of performance beyond standard optical imaging systems, with reduced size and complexity.”
T. Yang, D. H. Lippman, R. Y. Chou, N. S. Kochan, A. X. Desai, G. R. Schmidt, J. L. Bentley, and D. T. Moore, "Material optimization in the design of broadband gradient-index optics," OSA Optical Design and Fabrication 2021 (Flat Optics, Freeform, IODC, OFT), F. Capasso, W. Chen, P. Dainese, J. Fan, J. DeGroote Nelson, F. Duerr, J. Rogers, J. Rolland, P. Clark, R. Pfisterer, H. Rehn, S. Thibault, M. Jenkins, D. Wook Kim, and N. Trela-McDonald, eds., OSA Technical Digest (Optica Publishing Group, 2021), paper 120780Z.
“Gradient-index (GRIN) optics are commonly optimized with pre-determined materials, but the material choices limit the solution space of optimized index profiles. If the dispersive properties of the materials generating GRIN can be optimized, the performance of the optics can be further improved. This paper proposes a material concentration-based GRIN representation to replace the widely used index-based representation, allowing simultaneous optimization of materials and the GRIN profile.”
Cannamela, Madeleine G. "Magnetic Properties of Polymer Nanocomposite Materials Prepared using Multi Jet Fusion 3D Printing Methods." (2021).
The goal of this research was to explore if an inkjet 3D printing technology, known as Multi Jet Fusion (MJF), could be used to fabricate magnetic polymer nanocomposites with systematically varied volume fractions of magnetic nanoparticles. Soft magnetic nanoparticles were chosen because of their applications in communications technologies and other high frequency applications. However, the fabrication process described could be applied to other functional nanoparticles with, for example, conductive or dielectric properties. Magnetization and magnetic permeability were analyzed for each nanocomposite and plotted as functions of volume fraction.”
Kremer, Matthew H. "Electrospray Deposition of Discrete Nanoparticles: Studies on Pulsed-Field Electrospray and Analytical Applications." (2019)
“Electrospinning and electrospray are both nano-scale material fabrication techniques, based on related phenomena of electrically charged fluid spray from a droplet of liquid. Material is dissolved in liquid, then a spray is generated by applying a high voltage, creating an electric field, between the fluid dispensing capillary and a grounded collection substrate. Nano-scale features of the dissolved material are collected when the solvent evaporates in flight between the needle and collection substrate. Though electrospinning and electrospray are terms that can be used interchangeably (they frequently are) electrospinning specifically refers to using the technique to generate nanofibers; electrospray is a more appropriate term for the spray of individual, charged droplets. Electrospray theory is also seen applied in electrospray ionization interfaces to mass spectrometers. The underlying principles of electrospray for mass spectrometry and electrospray for deposition are the same, but deposition targets a bulk coating of material instead of quantitative analysis of a small number of gas phase analytes. In this work, electrospray deposition of discrete features from individual, charged droplets was realized. There is some literature published on this topic, but electrospinning literature is overwhelmingly populated with work on the fabrication of continuous nanofibers and “beaded features” are typically considered as defects in desired morphologies. A significant portion of this work was in collaboration on a DARPA funded research project with a local industry sponsor. Due to compliance with non-disclosure, the exact motivation and specific applications to that project cannot be discussed in this thesis, although the premise can be addressed. The broad goal of the project was development of techniques and methodology for assembling structures comprising features spanning nano, micro and macro scale dimensions. On that project, electrospray was used to fabricate discrete nanoplate features on the order of 100-200nm in size. These features were deposited, using the electrospray technique, onto a branched architecture with dimensions on the micron length scale. Effort went toward controlling the size of these features through electrospray parameters and demonstrating the repeatability in deposition of these features onto the device architecture. Outside of the sponsored project work, generation of discrete nano-plate/particle features from protein and polymer materials was used in both direct applications and to investigate the impact of pulsed high voltage (or pulsed-field) on the electrospray process. The technique was used directly in two analytical chemistry applications: first, the deposition of blood coagulation chemistries onto a point-of-care-applicable blood plasma separation device, with the goal of improving its separative performance; and second, electrospray deposition of an enzyme on the working electrode in an electrochemical sensor application for glucose detection. Design, fabrication, and implementation of custom components was done using 3D printing, laser cutting, and CNC end-milling to facilitate both research toward the sponsored project and work discussed in this thesis. An acrylic enclosure was used for the depositions and saw several modifications to meet changing research needs. To study pulsed-field electrospray a transformer-based high voltage system was designed and assembled in-lab. This system had limitations but was applicable for generating high voltage pulse waveforms and was used to perform electrospray deposition research.”