The Boston University Photonics Center annual report 2015-2016

This repository item contains an annual report that summarizes activities of the Boston University Photonics Center in the 2015-2016 academic year. The report provides quantitative and descriptive information regarding photonics programs in education, interdisciplinary research, business innovation, and technology development. The Boston University Photonics Center (BUPC) is an interdisciplinary hub for education, research, scholarship, innovation, and technology development associated with practical uses of light.This has been a good year for the Photonics Center. In the following pages, you will see that this year the Center’s faculty received prodigious honors and awards, generated more than 100 notable scholarly publications in the leading journals in our field, and attracted $18.9M in new research grants/contracts. Faculty and staff also expanded their efforts in education and training, and cooperated in supporting National Science Foundation sponsored Sites for Research Experiences for Undergraduates and for Research Experiences for Teachers. As a community, we emphasized the theme of “Frontiers in Plasmonics as Enabling Science in Photonics and Beyond” at our annual symposium, hosted by Bjoern Reinhard. We continued to support the National Photonics Initiative, and contributed as a cooperating site in the American Institute for Manufacturing Integrated Photonics (AIM Photonics) which began this year as a new photonics-themed node in the National Network of Manufacturing Institutes. Highlights of our research achievements for the year include an ambitious new DoD-sponsored grant for Development of Less Toxic Treatment Strategies for Metastatic and Drug Resistant Breast Cancer Using Noninvasive Optical Monitoring led by Professor Darren Roblyer, continued support of our NIH-sponsored, Center for Innovation in Point of Care Technologies for the Future of Cancer Care led by Professor Cathy Klapperich, and an exciting confluence of new grant awards in the area of Neurophotonics led by Professors Christopher Gabel, Timothy Gardner, Xue Han, Jerome Mertz, Siddharth Ramachandran, Jason Ritt, and John White. Neurophotonics is fast becoming a leading area of strength of the Photonics Center. The Industry/University Collaborative Research Center, which has become the centerpiece of our translational biophotonics program, continues to focus onadvancing the health care and medical device industries, and has entered its sixth year of operation with a strong record of achievement and with the support of an enthusiastic industrial membership base

Electrical test structures and measurement techniques for the characterisation of advanced photomasks

Existing photomask metrology is struggling to keep pace with the rapid reduction of IC dimensions as traditional measurement techniques are being stretched to their limits. This thesis examines the use of on-mask probable electrical test structures and measurement techniques to meet this challenge and to accurately characterise the imaging capabilities of advanced binary and phase-shifting chrome-on-quartz photomasks. On-mask, electrical and optical linewidth measurement techniques have highlighted that the use of more than one measurement method, complementing each other, can prove valuable when characterising an advanced photomask process. Industry standard optical metrology test patterns have been adapted for the direct electrical equivalent measurement and the structures used to characterise different feature arrangements fabricated on standard and advanced photomasks with proximity correction techniques. The electrical measurements were compared to measurements from an optical mask metrology and verification tool and a state-of-the-art CD-AFM system and the results have demonstrated the capability and strengths of the on-mask electrical measurement. For example, electrical and AFM measurements on submicron features agreed within 10nm of each other while optical measurements were offset by up to 90nm. Hence, electrical techniques can prove valuable in providing feedback to the large number of metrology tools already supporting photomask manufacture, which in turn will help to develop CD standards for maskmaking. Electrical test structures have also been designed to enable the characterisation of optical proximity correction to characterise right angled corners in conducting tracks using a prototype design for both on-mask and wafer characterisation. Measurement results from the on-mask structures have shown that the electrical technique is sensitive enough to detect the effect of OPC on inner corners and to identify any defects in the fabricated features. For example less than 10 (5%) change in the expected resistance data trends indicated a deformed OPC feature. Results from on-wafer structures have shown that the correction technique has an impact on the final printed features and the measured resistance can be used to characterise the effects of different levels of correction. Overall the structures have shown their capability to characterise this type of optical proximity correction on both mask and wafer level. Test structures have also been designed for the characterisation of the dimensional mismatch between closely spaced photomask features. A number of photomasks were fabricated with these structures and the results from electrical measurements have been analysed to obtain information about the capability of the mask making process. The electrical test structures have demonstrated the capability of measuring tool and process induced dimensional mismatches in the nanometer range on masks which would otherwise prove difficult with standard optical metrology techniques. For example, electrical measurements detected mismatches of less than 15nm on 500nm wide features

Amplificador CMOS de baixo ruído para imagiologia médica

Mestrado em Engenharia Electrónica e TelecomunicaçõesA presente dissertação aborda o projecto de um frontend analógico integrado para sincronização e amplificação de sinais produzidos por um fotomultiplicador de silício. A solução proposta pretende possibilitar medidas de tempo com resoluções na ordem dos picosegundos, para implementação em equipamentos compactos dedicados à Tomografia por Emissão de Positrões, com capacidade para medida do tempo de voo de fotões (TOFPET). O canal de frontend completo foi implementado em tecnologia CMOS 130nm, e compreende blocos de préamplificação, integração de carga, equilíbrio dinâmico do ponto de operação, bem como circuitos geradores de correntes de referência, para uma área total em silício de 500x90 μm. A discussão de resultados é baseada em simulações póslayout, e as linhas de investigação futuras são propostas.An analogue CMOS frontend for triggering and amplification of signals produced by a silicon photomultiplier (SiPM) is proposed. The solution intends to achieve picosecond resolution timing measurements for compact timeofflight Positron Emission Tomography (TOFPET) medical imaging equipments. A 130nm technology was used to implement such frontend, and the design includes preamplification, shaping, baseline holder and biasing circuitry, for a total silicon area of 500x90 μm. Postlayout simulation results are discussed, and ways to optimize the design are proposed

Cumulative index to NASA Tech Briefs, 1986-1990, volumes 10-14

Tech Briefs are short announcements of new technology derived from the R&D activities of the National Aeronautics and Space Administration. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This cumulative index of Tech Briefs contains abstracts and four indexes (subject, personal author, originating center, and Tech Brief number) and covers the period 1986 to 1990. The abstract section is organized by the following subject categories: electronic components and circuits, electronic systems, physical sciences, materials, computer programs, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences

Design of LCOS microdisplay backplanes for projection applications

De evolutie van licht emitterende diodes (LED) heeft ervoor gezorgd dat het op dit moment interessant wordt om deze componenten als lichtbron te gebruiken in projectiesystemen. LED’s hebben belangrijke voordelen vergeleken met klassieke booglampen. Ze zijn compact, ze hebben een veel grotere levensduur en ogenblikkelijke schakeltijden, ze werken op lage spanningen, etc. LED’s zijn smalbandig en kunnen een groterekleurenbereik realiseren. Ze hebben momenteel echter een beperkte helderheid. Naast de lichtbron is het type van de lichtklep ook bepalend voor de kwaliteit van een projectiesysteem. Er bestaan verschillende lichtkleptechnologieën waaronder die van de reflectieve LCOS-panelen. Deze lichtkleppen kunnen zeer hoge resoluties hebben en wordenvaak gebruikt in kwalitatieve, professionele projectiesystemen. LED’s zijn echter totaal verschillend van booglampen. Ze hebben een andere vorm, package, stralingspatroon, aansturing, fysische en thermische eigenschappen, etc. Hoewel er een twintigtal optische architecturen bekend zijn voor reflectieve beeldschermen (met een booglamp als lichtbron), zijn ze niet geschikt voor LED-projectoren en moeten nieuwe optische architecturen en een elektronische aansturing ontwikkeld worden. In dit doctoraat werd er hieromtrent onderzoek gedaan. Er werd uiteindelijk een driekleurenprojector (R, G, B) met een efficiënt LED-belichtingssysteem gebouwd met twee LCOS-lichtkleppen. Deze LEDprojector heeft superieure eigenschappen (zeer lange levensduur, beeldkwaliteit, etc.) en een matige lichtopbrengst

NASA Tech Briefs, August 1991

Topics: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Realtime image noise reduction FPGA implementation with edge detection

The purpose of this dissertation was to develop and implement, in a Field Programmable Gate Array (FPGA), a noise reduction algorithm for real-time sensor acquired images. A Moving Average filter was chosen due to its fulfillment of a low demanding computational expenditure nature, speed, good precision and low to medium hardware resources utilization. The technique is simple to implement, however, if all pixels are indiscriminately filtered, the result will be a blurry image which is undesirable. Since human eye is more sensitive to contrasts, a technique was introduced to preserve sharp contour transitions which, in the author’s opinion, is the dissertation contribution. Synthetic and real images were tested. Synthetic, composed both with sharp and soft tone transitions, were generated with a developed algorithm, while real images were captured with an 8-kbit (8192 shades) high resolution sensor scaled up to 10 × 103 shades. A least-squares polynomial data smoothing filter, Savitzky-Golay, was used as comparison. It can be adjusted using 3 degrees of freedom ─ the window frame length which varies the filtering relation size between pixels’ neighborhood, the derivative order, which varies the curviness and the polynomial coefficients which change the adaptability of the curve. Moving Average filter only permits one degree of freedom, the window frame length. Tests revealed promising results with 2 and 4ℎ polynomial orders. Higher qualitative results were achieved with Savitzky-Golay’s better signal characteristics preservation, especially at high frequencies. FPGA algorithms were implemented in 64-bit integer registers serving two purposes: increase precision, hence, reducing the error comparatively as if it were done in floating-point registers; accommodate the registers’ growing cumulative multiplications. Results were then compared with MATLAB’s double precision 64-bit floating-point computations to verify the error difference between both. Used comparison parameters were Mean Squared Error, Signalto-Noise Ratio and Similarity coefficient.O objetivo desta dissertação foi desenvolver e implementar, em FPGA, um algoritmo de redução de ruído para imagens adquiridas em tempo real. Optou-se por um filtro de Média Deslizante por não exigir uma elevada complexidade computacional, ser rápido, ter boa precisão e requerer moderada utilização de recursos. A técnica é simples, mas se abordada como filtragem monotónica, o resultado é uma indesejável imagem desfocada. Dado o olho humano ser mais sensível ao contraste, introduziu-se uma técnica para preservar os contornos que, na opinião do autor, é a sua principal contribuição. Utilizaram-se imagens sintéticas e reais nos testes. As sintéticas, compostas por fortes e suaves contrastes foram geradas por um algoritmo desenvolvido. As reais foram capturadas com um sensor de alta resolução de 8-kbit (8192 tons) e escalonadas a 10 × 103 tons. Um filtro com suavização polinomial de mínimos quadrados, SavitzkyGolay, foi usado como comparação. Possui 3 graus de liberdade: o tamanho da janela, que varia o tamanho da relação de filtragem entre os pixels vizinhos; a ordem da derivada, que varia a curvatura do filtro e os coeficientes polinomiais, que variam a adaptabilidade da curva aos pontos a suavizar. O filtro de Média Deslizante é apenas ajustável no tamanho da janela. Os testes revelaram-se promissores nas 2ª e 4ª ordens polinomiais. Obtiveram-se resultados qualitativos com o filtro Savitzky-Golay que detém melhores características na preservação do sinal, especialmente em altas frequências. Os algoritmos em FPGA foram implementados em registos de vírgula fixa de 64-bits, servindo dois propósitos: aumentar a precisão, reduzindo o erro comparativamente ao terem sido em vírgula flutuante; acomodar o efeito cumulativo das multiplicações. Os resultados foram comparados com os cálculos de 64-bits obtidos pelo MATLAB para verificar a diferença de erro entre ambos. Os parâmetros de medida foram MSE, SNR e coeficiente de Semelhança