Prof. San-Liang Lee
Chairman of Optics and Photonics Program MOST & National Taiwan University of Science and Technology (NTUST), Taiwan
Title of Lecture:
Photonic integration for applications in optical networking and optical sensing
Abstract:
Photonic integration circuits (PICs) are the disruptive technologies that will alter the competitiveness of various high-tech products and enable new applications. There exist different PIC platforms for different applications and wavelength bands. InP based PICs have been under intensive research for more than 30 years and found various applications optical networking. Silicon photonics (SiPh) platform, on the other hand, is the most attractive one due to its compatible with the fabrication process of mature CMOS integration circuits and also because of its high-contrast refractive indices for forming an optical waveguide, which leading to very compact waveguide and small bending radius. They are driving the evolution of data center interconnect, advanced driver assistance systems, internet of things, biomedical sensing, quantum computing, and intelligent industry. In this seminar, the research trend, applications, and challenges of InP- and SiPh-PICs will be addressed. Some design examples of PICs will be reported, with an emphasis on the applications to optical networking and optical sensing based on optical phase arrays. The heterogeneous integration that combines the technologies InP and SiPh to allow on-chip laser integration will also be addressed. We have developed silicon PICs for input/output coupling, optical network monitoring, 400-Gb/s optical transceivers. A large-scale PICs for applications in light detection and ranging (LiDAR) will be demonstrated with phase error correction for beam steering.
Prof. Joewono Widjaja
School of Laser Technology and Photonics, Institute of Science, Suranaree University of Technology, Thailand
Title of Lecture:
Holographic Particle Diagnosis Using Wigner-Ville Distribution
Abstract:
Holographic particle diagnosis is one of the useful optical methods for studying small particles. This is because the holographic method is able to store three-dimensional (3-D) particle information such as size and relative position via a recording of an interference pattern of diffracted wavefronts in photosensitive media. In digital particle holography, the recorded interference pattern, called a digital hologram, encodes the particle information as a nonstationary signal. Conventional information extraction from digital holograms is generally accomplished by solving either the Fresnel diffraction integral or the angular spectrum method via fast Fourier transform. However, the conventional methods require multiple image reconstructions for each particle at different depth positions. This is done to deal with real-world problems of unknown particle positions. Since there is only a single image reconstructed at the correct depth position has the best focus, the image sharpness of a set of reconstructed images needs to be quantitatively evaluated. This is an inherent drawback of the conventional numerical methods, which require a very high number of reconstructed images.
Dr. Sasono Rahardjo
Electronics Research Center of The National Research and Innovation Agency (BRIN)
Title of Lecture:
Why Underwater Integrated Telecommunication/Sensors Need to be Built in Indonesia: Considerations and Support for Future Development
Starting from 2019, BPPT (now merged as the National Research and Innovation Agency-BRIN) has been developing cable based tsunameter (CBT) and has been studying for more complex system. CBT itself is a task given by the president of the Republic of Indonesia under the presidential decree no 93/2019 article 13, which has 4 points, i.e.:
a. Integrating the results of deep-sea level of tsunami observation with early warning system that organized by the non-ministerial government agency which carries out government affairs in the field of meteorology, climatology, and geophysics for 24 hours actually and continuously.
b. Innovating observation technology on earthquakes, deep-sea level tsunami, cable based tsunameter, and other oceanic observations.
c. Carrying out scheduled communication tests.
d. Ensuring the data availability of deep-sea level tsunami and communication network in operational condition.
Our talk will present what have been done for the preparation of the system to its deployment on the determined area, some of the system considerations, and why our nation should be prepared for this kind of technology.
Prof. Huang Zhiwei
Department of Biomedical Engineering, National University of Singapore (NUS), Singapore
Title of Lecture:
TBA
Dr.Ing Rajesh Kanawade
CSIR-Central Scientific Instruments Organisation & Academy of Scientific and Innovative Research (AcSIR) India
Title of Lecture:
Advanced Materials and Fiber Optic Sensors
Efficient and fast sensing of toxic, harmful gases as well as strong and weak acids has become more and more essential for the environment, our own safety, and industrial product monitoring, as well as in manufacturing. Currently, electrochemical and optical-based sensors are used for sensing applications. The electrochemical (semiconducting oxide materials) gas sensors show excellent performance in terms of sensitivity, however, these sensors usually operated at high temperature (200 – 600°C), also needs long measuring period, weak stability, and high manufacturing cost restrict its on-site gas monitoring and its real-time analysis applications. Optical fiber-based sensors could be the best option due to its major advantages, such as fast responses, immune to electromagnetic, lightweight, high sensitivity and miniaturized setup.
In this work, a Fabry-Perot Interferometer (FPI) based polymer coated sensor platform for sensing of toxic, harmful gases, temperature as well as strong and weak acid has been demonstrated at room temperature. Various polymers coating, coating thickness and fiber geometries are explored for of the sensor platform preparation. Results show that the different polymers show different cross-sensitivity to different gases as well as strong/weak Acids.
The principle of sensing is based on change in the length of the FPI cavity in presence of varying concentrations which results in changes in the total reflectance due to the shift in wavelength of an interference pattern. The evaluation parameters of the developed sensor like sensitivity, limit of detection, response and recovery time for the toxic, harmful gases, temperature as well as strong and weak acid sensing at room temperature were measured. The observed results confirm that the proposed sensor shows high sensitivity and good selectivity. The aim of this study was to explore the feasibility of Fiber optic FPI for efficient and fast sensing of toxic, harmful gases, temperature as well as strong and weak acid.
Tatas Brotosudarmo, Ph.D
Department of Food Technology, Universitas Ciputra Surabaya
Title of Lecture:
Protein Aging Observed by Its Optical Properties: A Lesson Learn on the Light-Harvesting Complex of the Marine Green Algae Codium fragile
Abstract:
The siphonaxanthin-siphonein-Chl a/b-protein (SCP) is the light-harvesting complex of the marine alga Codium fragile. Its structure resembles that of the major light-harvesting complexes of higher plants, LHC II, yet it features a reversed Chl a: Chl b ratio and it accommodates other variants of carotenoids. In contrast to the LHCs from higher plants, the antennae systems from marine algae have recently attracted attention. Codium fragile has its habitat in open coasts and tidal pools, but it can also be found underwater at a depth of up to about 20 m. The optical properties of SCP can be recognized by the ability to use blue-green light, which is the dominating spectral range underwater. While conducting measurements of SCP fluorescence emission spectra and fluorescence lifetimes from ensembles and single complexes, we observed the occurrence of the aging process. This process is manifested as a lowering of energetic barriers within the protein, enabling thermal activation of conformational changes at room temperature and a red-shifted state that features the optical properties that dominated the population along with a significant decrease in the fluorescence lifetime. Here at the conference, our currently published results will be presented and discussed.
Dr. Vincent Daria
Research School of Physics, College of Science, Australian National University, Australia
Title of Lecture:
Decoding the computing power of neurons using light
Abstract:
Decoding the computing power of single neurons is a pre-requisite to understand how our brain works. The dendritic tree of neurons receives synaptic inputs carrying different types of information. Our aim is to identify the roles of different dendritic domains in the processing of synaptic inputs and how the spatiotemporal organization of the inputs eventually sets the neuron to fire an output. To achieve this aim, we use a custom-built holographic two-photon laser microscope to analyse the role of dendrites in the neuron’s computing function. The microscope allows us to render 3D images of the neurons, while programmable hologram transforms an incident laser into spatially distributed multiple foci. We can program the hologram to position the different foci along different dendritic regions of the neuron in 3D. Each focus can be used to trigger a synaptic input or as an optical probe to record the activity of the neuron. To artificially trigger synaptic inputs, a focal stimulation represents a synaptic input via two-photon photolysis of caged neurotransmitters or activate genetically encoded light-activated ion-channels. On the other hand, the laser focus can also be used to record neuronal activity via functional calcium and voltage imaging using molecular dye reporters or genetically encoded calcium/voltage indicators. Using this microscope, we have identified a unique function of a specific set of dendrites that can play a role in the brain’s capacity to learn and memorize. Understanding the functional role different dendrites of neurons can provide bottom-up approach to decode the computing power of the brain.