Session Overview |
Thursday, May 30 |
13:00 |
Refractive index changes in Mach-Zehnder waveguide interferometers for biological applications
Luis Antonio Tapia-Licona, Centro de Investigaciones en Óptica, A. C. * Gloria Verónica Vázquez, Centro de Investigaciones en Óptica, A. C., Mexico Erika Rodríguez-Sevilla, Centro de Investigaciones en Óptica, A. C. Rubí Reséndiz-Ramírez, Centro de Investigaciones en Óptica, A. C. This work presents the simulation and fabrication of different Mach-Zehnder waveguide interferometers (MZWIs) on fused silica substrates manufactured through femtosecond direct laser writing (FDLW). Rotated interferometers were created such that one of the arms is written near the interaction surface, where the sensing region has a length of 1, 3 or 6 mm. The results show that by varying the sensing region dimensions, we can control the device's sensitivity. The interferometer was designed in an unbalanced configuration, with the shorter arm containing this sensing region and the longer arm allowing us to generate a geometric path difference of approximately 33 µm. This facilitates the generation of an interference pattern over a wavelength scanning range from 1470 to 1560 nm. |
13:15 |
Highly efficient imaging spatial transcriptomics with compressed sensing at low magnification
* Jahanara Freedman, Broad Institute of MIT and Harvard, United States of America Lindsey Erion Barner, Broad Institute of MIT and Harvard Nicolas Lapique, Broad Institute of MIT and Harvard John P. Bryan, Broad Institute of MIT and Harvard Brian Cleary, Boston University Samouil L. Farhi, Broad Institute of MIT and Harvard Highly multiplexed spatial transcriptomics imaging (iST) is a valuable tool to characterize in situ gene expression. Current techniques face limitations in acquisition time and optical crowding for highly expressed genes, making it incompatible with large tissue throughput. This study uses Composite In Situ Imaging (CISI) to overcome these challenges by translating early implementations of this study to lower magnification using rolling circle amplification fluorescent in situ hybridization (RCA FISH) to amplify signals beyond previous levels and enable greater overall throughput. |
13:30 |
DNN-based signal-to-noise ratio enhancement of 3D retinal images from multiple spectrometer-based SD-OCT system
Sanghyuk Suh, Kangwon National University, South Korea * Jun Song, Universitry of British Columbia, Canada Myeong Jin Ju, Universitry of British Columbia, Canada Hee-Jae Jeon, Kangwon National University, South Korea Implementation of multiple spectrometers into a spectral-domain optical coherence tomography (SD-OCT) could effectively enhance the imaging speed or signal-to-noise ratio (SNR), but these two enhancements could not be made simultaneously. In this study, we demonstrated the generation of retinal OCT images with advanced SNR using DNN platform from images acquired at high-speed but low-SNR. We confirmed that images produced from the DNN platform showed a high Peak Signal-to-Noise Ratio (PSNR) when compared to ground truth images. The proposed method proved its potential to be implemented into multiple spectrometer-based SD-OCT systems to take the advantages in speed and SNR at the same time. |
13:45 |
Bio-Inspired Polarization Compass for Solar Azimuth Prediction
* Devyansh Agarwal, Queen's University, Canada Benjamin Potter, Queen's University, Canada Jawad Siddiqui, Queen's University, Canada Yahia Antar, Royal Military College of Canada, Canada Muhammad Alam, Queen's University, Canada This work investigates and compares the predictive performance of Support Vector Machine (SVM) and Linear Regression models in determining the solar azimuth under diverse sky conditions. Stoke vector images of skylight polarization are obtained using a polarization camera and used in the designed models. This research contributes to the ongoing exploration and development of polarization compass for navigation. |
14:00 |
Potential-resolved multicolor, multianalyte electrochemiluminescence detection on CMOS semiconductor image sensor; Optimized and miniaturized SE-ECL
* Reza Abbasi, McGill University, Canada Sebastian Wachsmann-Hogiu, McGill University, Canada Recently, there has been a notable focus on integrating microfluidic devices with semiconductor imaging sensors [1]. For instance, we previously integrated microfluidic elements with luminol–H2O2 ECL systems on a CMOS chip, repurposing a single electrode as an electrochemical transducer and the CMOS chip as an integrated detector. This approach was successfully applied to detect uric acid in saliva and urine [2]. Subsequent work has refined SE-ECL configurations, enhancing sensitivity and specificity in analyte detection, and achieving compact integration with a CMOS image sensor. These advancements exploit differences in electric potential along single electrodes, allowing selective excitation of ECL luminophores to produce distinct colors. We optimized channel length and width to improve ECL emission and found that AC-driven SE-ECL yields increased light intensity compared to DC voltage, with square waveforms proving more effective than sine waveforms. Furthermore, we demonstrated multiplexed multicolor SE-ECL of Ru (II) and Ir (III) luminophores for simultaneous measurement of five or six analytes. The analytes can be separated by channel alone, by potential along the same channel, and by potential and color within one channel. Integrating a multi-channel microfluidic chip with SE-ECL enabled further miniaturization, implemented on a 6.5 mm × 3.6 mm CMOS semiconductor image sensor. This innovative approach involves a single electrode design initiating ECL reactions with different colors, employs microfluidic techniques for efficient sample manipulation, and utilizes an economical and energy-efficient CMOS sensor for capturing emitted light during ECL reactions. Collectively, these enhancements promise the development of more accurate and compact biosensors for point-of-care biomedical, food safety, or environmental monitoring applications. |
14:15 |
Double Ring Resonator Integrated with 3x3 MMI for High Sensitivity Refractive Index Sensing on Silicon Nitride on Insulator Platform
Alaa Sultan, American university in cairo, Egypt * Mohamed A. Swillam, American university in cairo, Egypt In this paper, we introduce a double ring resonator (DRR) integrated with a 3x3 multimode interferometer (MMI) structure for refractive index sensing applications, employing a Silicon Nitride on Insulator (SiNOI) platform. The platform's high sensitivity, coupled with low optical losses, makes it particularly well-suited for sensors and devices requiring precise detection capabilities. Its wide transparency range in the visible and near-infrared spectrum adds versatility to its applications. A subtle modification in the refractive index near the MMI structure induces a shift in the device's resonance wavelength, establishing it as an effective refractive index sensor. The proposed device exhibits a sensitivity of 740 nm/RIU within the refractive index range of 1.33 to 1.36, coupled with an impressive figure of merit (FOM) of 210 |