About

Thomas Bifano, PhD, is a Professor in the Department of Mechanical Engineering at Boston University and the Director of the Photonics Center (BUPC). He has a primary appointment in Mechanical Engineering and has served as Chair of the Manufacturing Engineering Department from 1999 to 2006. Dr. Bifano directs the Boston University Photonics Center, a core facility and academic center of excellence that includes faculty from eight academic departments and staff members. His leadership involves overseeing programs for education, scholarly research, and the development of advanced photonic device prototypes for both commercial and military applications. He manages a state-of-the-art facility comprising shared research laboratories and a large business innovation center. His research focuses on modeling, design, production, and use of micro-electro-mechanical systems (MEMS) in optical applications, with specific interests in deformable mirrors, MEMS, adaptive optics, biphotonic microscopy, astronomical telescope instrumentation, and laser wavefront control. Dr. Bifano's affiliations extend across multiple departments and divisions, including Biomedical Engineering, Materials Science & Engineering, Electrical & Computer Engineering, and Neuroscience & Neuroengineering, among others.

Research topics

• Computer Science
• Materials science
• Physics
• Optics
• Acoustics
• Optoelectronics
• Biology
• Artificial Intelligence
• Embedded system
• Neuroscience
• Composite material

Selected publications

• Editorial: Advanced fabrication techniques for high-precision optical components

  Advanced Optical Technologies · 2026-04-14

  articleOpen access

  depends on mastering process physics across scales from interface chemistry and residual stress to tool kinematics and closed-loop control. This Research Topic highlights advanced fabrication routes that not only improve individual process parameters but also deepen our understanding of the mechanisms governing accuracy, surface integrity, manufacturability and functional performance.A recurring message across the Topic is that precision fabrication is no longer defined only by the final shape of a component. It is equally determined by what happens at interfaces, during energy transfer and throughout process integration. This broader perspective is especially clear in the contributions addressing molding and polishing. Zhao and Zhang provide a timely overview of mold-glass adhesion in precision glass molding, identifying wettability, work of adhesion, coating stability and thermomechanical evolution as key factors that control both product quality and mold durability. Their analysis is important because it reframes demolding not as a secondary step but as a central scientific and engineering problem in scalable optics manufacturing. In a complementary direction, Jian et al. examine femtosecond laser polishing of silicon nitride and position ultrafast processing as a green non-contact route for difficult-to-machine optical ceramics. By linking material removal physics to process windows and industrial outlook, this contribution extends the Topic from component fabrication toward future-ready surface engineering.At the level of glass structuring, Henkel et al. address one of the persistent challenges in optical manufacturing: the generation of high-aspect-ratio internal features in fused silica. Their comparison of deep drilling and helical drilling, with and without ultrasonic tool oscillation, shows that the effectiveness of assistance depends strongly on the kinematic strategy. Most notably, ultrasonic excitation substantially improves dimensional fidelity in helical drilling, while deep drilling remains advantageous for bore-wall quality and accuracy under the selected conditions. Beyond the immediate drilling results, this study is significant because it points toward more flexible manufacturing of complex internal optical geometries including structures relevant to fiber preforms and precision glass devices.The Topic also demonstrates that fabrication advances are equally critical in active and freeform optics. Man and Bifano present an electromagnetic deformable mirror that combines silicon micromachining with a stress-resilient assembly concept. By moving the adhesive interface to the distal ends of slender integral posts, they reduce assembly-induced face-sheet distortion while retaining a compliant structure capable of large actuation. The resulting prototype achieves bidirectional actuation with total stroke exceeding 20 μm and millisecondscale dynamic response, illustrating how fabrication design and functional optical performance must be considered together. In another contribution, Santiago-Alvarado et al. develop a practical route for manufacturing a toroidal aluminum mold for polymeric lenses successively using five-axis CNC milling, polishing, null-screen testing and coordinate measurement. Their work is valuable not only for the mold itself but also for the lower cost and more accessible pathway it demonstrates for freeform optics manufacturing and verification.In summary, the contributions in this Research Topic point to several important themes in advanced optical fabrication. First, interface-related phenomena play an increasingly important role in shaping process outcomes, from mold-glass adhesion in precision glass molding to adhesive stress in adaptive optics and laser-material interaction in ceramic finishing. Second, the Topic underscores the value of hybrid process strategies, in which assistance methods, assembly concepts, polishing steps, and metrology are combined to extend fabrication capability. Third, the studies show that metrology and process design are becoming more closely linked, supporting more robust and application-oriented manufacturing routes for highprecision optical components.Overall, this collection bridges fundamental process mechanisms with practical manufacturing challenges across passive and active optics, brittle glasses and advanced ceramics, and both high-end and cost-effective production routes. Rather than treating fabrication as a sequence of isolated steps, the articles highlight the importance of integrating materials understanding, process control, surface engineering, and metrology. This broader perspective is likely to remain important for the development of next-generation high-precision optical components with improved accuracy, surface integrity, and manufacturability.Keywords: high-precision optical components, advanced fabrication, ultraprecision machining, freeform optics, surface finishing

  PublisherOA PDFDOI

• Physics-Aware Machine-Learning-Driven Inverse Design of Broadband Ultra-Open Acoustic Metamaterials

  arXiv (Cornell University) · 2026-05-15

  preprintOpen access

  Ventilated acoustic silencers combing sound attenuation with high ventilation are pivotal for advanced noise control. However, balancing attenuation, bandwidth, openness, and thickness remains a high-dimensional challenge. Here, we report a physics-aware machine-learning-driven inverse design framework for ultra-open acoustic silencers (UAS). By leveraging Green's function-based parameterization, we physically decouple the design space into spectral and radial parameters, ensuring physical interpretability while reducing complexity. We introduce a two-stage forward prediction architecture that captures broadband envelopes and sharp resonant features via a coarse-to-fine strategy. Coupled with a population-based, hybrid-objective parallel (PHP) inverse strategy, our framework enables rapid exploration of non-convex landscapes, identifying hundreds of optimized candidates within seconds. Crucially, this framework uncovers hidden linear design rules that govern high-performance monolithic designs, acting as geometric proxies for optimal impedance-matching. We experimentally validate a family of prototypes: UAS-2 demonstrates the monolithic limit with high ventilation ratio, while UAS-3 demonstrates versatility in multi-mode interactions. To circumvent the trade-off ceiling of single-unit resonators, a parallel-composite architecture (UAS-4) is introduced to enhance performance through spatial interference distribution. Results confirm a broadband bandwidth exceeding 830 Hz achieved with an ultra-thin profile (0.1-0.2λ) and 80% ventilation. This work establishes a data-driven paradigm for discovering design principles in functional metamaterials.

  PublisherDOI

• Physics-Aware Machine-Learning-Driven Inverse Design of Broadband Ultra-Open Acoustic Metamaterials

  ArXiv.org · 2026-05-15

  articleOpen access

  Ventilated acoustic silencers combing sound attenuation with high ventilation are pivotal for advanced noise control. However, balancing attenuation, bandwidth, openness, and thickness remains a high-dimensional challenge. Here, we report a physics-aware machine-learning-driven inverse design framework for ultra-open acoustic silencers (UAS). By leveraging Green's function-based parameterization, we physically decouple the design space into spectral and radial parameters, ensuring physical interpretability while reducing complexity. We introduce a two-stage forward prediction architecture that captures broadband envelopes and sharp resonant features via a coarse-to-fine strategy. Coupled with a population-based, hybrid-objective parallel (PHP) inverse strategy, our framework enables rapid exploration of non-convex landscapes, identifying hundreds of optimized candidates within seconds. Crucially, this framework uncovers hidden linear design rules that govern high-performance monolithic designs, acting as geometric proxies for optimal impedance-matching. We experimentally validate a family of prototypes: UAS-2 demonstrates the monolithic limit with high ventilation ratio, while UAS-3 demonstrates versatility in multi-mode interactions. To circumvent the trade-off ceiling of single-unit resonators, a parallel-composite architecture (UAS-4) is introduced to enhance performance through spatial interference distribution. Results confirm a broadband bandwidth exceeding 830 Hz achieved with an ultra-thin profile (0.1-0.2λ) and 80% ventilation. This work establishes a data-driven paradigm for discovering design principles in functional metamaterials.

  PublisherOA PDF

• Electromagnetic deformable mirror fabricated using silicon micromachining and stress-resilient assembly

  Advanced Optical Technologies · 2025-01-22

  articleOpen accessSenior author

  Introduction: This work presents a prototype electromagnetic actuation deformable mirror (DM) assembly with stress-resilient face sheet design. Methods: The DM face sheet design includes slender micromachined silicon pillars that are integrated with a silicon face sheet to reduce unpowered face sheet surface distortion caused by actuator adhesion stress. Results: The assembled deformable mirror prototype allowed bi-directional actuation with total stroke exceeding 20 μm. A two-step control method was used to improve the prototype dynamic performance, allowing settling time on the order of 1 ms. Prescribed references shapes were made on the prototype deformable mirror using closed-loop control. Discussion: While the simplified DM produced in this work has only 19 actuators and therefore has limited capacity to control complex shapes, the design and fabrication processes described and demonstrated in this work provide a promising approach to development of high-stroke magnetic DMs.

  PublisherOA PDFDOI

• Superresolution imaging of live samples by centroid reassignment microscopy

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-08-03

  preprintOpen access

  Superresolution imaging has become one of the most important recent advances in microscopy development. However, most superresolution methods are ill-adapted for live-sample imaging because they are unacceptably slow, susceptible to artifacts, or require the use of specialized fluorophores and labeling protocols. We introduce a superresolution method called centroid reassignment microscopy (CRM) that overcomes these limitations. CRM is a simple variation on confocal microscopy wherein the single-element detector and small pinhole are replaced by a centroid detector and larger pinhole. Superresolution is obtained by reassigning the centroid location of the detected fluorescence as a function of the scanning excitation focus location. Our method bears resemblance to the method of image scanning microscopy, which involves the use of an array detector, with the advantage that CRM provides improved resolution for the same number of detected photons while being simpler to implement. CRM is light-efficient, fast (single frame), robust to defocus aberrations, and requires no changes whatsoever in standard fluorescence imaging protocols, making it uniquely attractive for superresolution imaging of live, dynamic samples.

  PublisherOA PDFDOI

• Multiscale mechanics of polydimethylsiloxane: A comparison of meso‐ and micro‐cyclic deformation behavior

  Journal of Applied Polymer Science · 2024-04-06 · 2 citations

  article

  Abstract Despite plenty of static and dynamic mechanical measurements and modeling for bulk polydimethylsiloxane (PDMS) specimens, a notable gap exists in comprehensively understanding the dynamic mechanics under large cycle, low strain conditions, especially for microscale samples. This study integrates tensile testing and nanoindentation techniques to compare dynamic mechanical response for bulk PDMS samples and μ‐pillars. The results from cyclic tensile testing, which involved up to 10,000 cycles at a strain range of 10%–20%, indicate a stabilization of energy dissipation rate after the initial 25 cycles. This attributes to stress relaxation and strain hardening, validating by rapid dual‐phase exponential decay in maximum stress, coupled with an incremental increase in elastic modulus. In comparison to tensile testing, μ‐pillars exhibited a 0.82% reduction in stiffness, stabilizing ~600th cycle. Concurrently, there was an approximately twofold increase in approaching distance during the initial 120 cycles, and an approximately fourfold increase in dissipated energy over the first 80 cycles, before reaching a plateau. This lagging hysteresis effect attributes to the distribution of the resultant force, including top tension, bottom compression, and base tilt. Overall, this study illuminates temporal mechanical deformations in PDMS under two application scenarios, enhancing our understanding of PDMS mechanical behavior.

  PublisherDOI

• Computational‐Design Enabled Wearable and Tunable Metamaterials via Freeform Auxetics for Magnetic Resonance Imaging

  Advanced Science · 2024 · 8 citations

  • Computer Science
  • Computer Science
  • Materials science

  Metamaterials hold significant promise for enhancing the imaging capabilities of magnetic resonance imaging (MRI) machines as an additive technology, due to their unique ability to enhance local magnetic fields. However, despite their potential, the metamaterials reported in the context of MRI applications have often been impractical. This impracticality arises from their predominantly flat configurations and their susceptibility to shifts in resonance frequencies, preventing them from realizing their optimal performance. Here, a computational method for designing wearable and tunable metamaterials via freeform auxetics is introduced. The proposed computational-design tools yield an approach to solving the complex circle packing problems in an interactive and efficient manner, thus facilitating the development of deployable metamaterials configured in freeform shapes. With such tools, the developed metamaterials may readily conform to a patient's knee, ankle, head, or any part of the body in need of imaging, and while ensuring an optimal resonance frequency, thereby paving the way for the widespread adoption of metamaterials in clinical MRI applications.

  PublisherDOI

• Induced pluripotent stem cell-derived cardiomyocyte in vitro models: benchmarking progress and ongoing challenges

  Nature Methods · 2024-11-08 · 31 citations

  reviewOpen access
  PublisherOA PDFDOI

• Computational‐Design Enabled Wearable and Tunable Metamaterials via Freeform Auxetics for Magnetic Resonance Imaging (Adv. Sci. 26/2024)

  Advanced Science · 2024-07-01 · 1 citations

  articleOpen access

  Computational‐Design In 2400261 by Stephan W. Anderson, Xin Zhang, and co‐workers, a computational method is reported to design wearable and tunable metamaterials via freeform auxetics for magnetic resonance imaging. The computational design tool offers an approach to solving complex circle packing problems in an interactive and efficient manner, thereby facilitating the design of deployable structures and the creation of mechanically tunable metamaterials configured in freeform shapes. [Image: see text]

  PublisherOA PDFDOI

• Dynamic Control of Contractile Force in Engineered Heart Tissue

  IEEE Transactions on Biomedical Engineering · 2023-01-24 · 13 citations

  articleOpen accessSenior author

  Three-dimensional engineered heart tissues (EHTs) derived from human induced pluripotent stem cells (iPSCs) have become an important resource for both drug toxicity screening and research on heart disease. A key metric of EHT phenotype is the contractile (twitch) force with which the tissue spontaneously beats. It is well-known that cardiac muscle contractility - its ability to do mechanical work - depends on tissue prestrain (preload) and external resistance (afterload). OBJECTIVES: Here, we demonstrate a technique to control afterload while monitoring contractile force exerted by EHTs. METHODS: We developed an apparatus that can regulate EHT boundary conditions using real-time feedback control. The system is comprised of a pair of piezoelectric actuators that can strain the scaffold and a microscope that can measure EHT force and length. Closed loop control allows dynamic regulation of effective EHT boundary stiffness. RESULTS: When controlled to switch instantaneously from auxotonic to isometric boundary conditions, EHT twitch force immediately doubled. Changes in EHT twitch force as a function of effective boundary stiffness were characterized and compared to twitch force in auxotonic conditions. CONCLUSION: EHT contractility can be regulated dynamically through feedback control of effective boundary stiffness. SIGNIFICANCE: The capacity to alter the mechanical boundary conditions of an engineered tissue dynamically offers a new way to probe tissue mechanics. This could be used to mimic afterload changes that occur naturally in disease, or to improve mechanical techniques for EHT maturation.

  PublisherDOI

Recent grants

• IUCRC Collaborative Research: I/UCRC: Center for Biophotonic Sensors and Systems (CBSS)

  NSF · $480k · 2011–2017

• Phase II I/UCRC Trustees of Boston University: Center on Biophotonic Sensors and Systems

  NSF · $102k · 2017–2018

Frequent coauthors

• Paul Bierden

  Boston Micromachines (United States)

  39 shared

• Steven Cornelissen

  Boston Micromachines (United States)

  35 shared

• Jérôme Mertz

  30 shared

• Yang Lu

  24 shared

• Hari P. Paudel

  National Energy Technology Laboratory

  24 shared

• Jason B. Stewart

  K Lab (United States)

  23 shared

• T. A. Dow

  North Carolina State University

  22 shared

• Bennett B. Goldberg

  Boston University

  20 shared

Education

• Ph.D., Electrical Engineering

  Boston University

  1997

• M.S., Electrical Engineering

  Boston University

  1993

• B.S., Electrical Engineering

  University of Massachusetts Amherst

  1991