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As a new type of water operation platform in recent years, surface unmanned boats have gradually become a hotspot for many scholars to study. The path planning capability of unmanned boat is an important measure of the intelligence degree of unmanned boat. To address the obstacle avoidance problem of surface autonomous unmanned boat path planning, this paper proposes a global path planning method for surface autonomous unmanned boats based on the improved grid method by modeling the known water environment with a grid method. In order to accurately simulate the impact of obstacles on the path planning of surface autonomous unmanned boats due to the drifting effect, this paper simulates the drifting increment of obstacles on the water surface by setting different obstacle forms and sizes, and conducts a MATLAB simulation platform to simulate the drifting increment of obstacles on the water surface. The simulation experiments prove the real reliability of the improved obstacle avoidance strategy algorithm proposed in the main paper.

In this paper, in order to track and measure the long-distance target, a continuous zoom optical system with a diameter of 400mm and focal length of 1000mm-4000mm is designed. The imaging quality evaluation of optical system is mainly carried out from the following five aspects: field curvature, distortion, transfer function MTF of optical system, energy concentration and spot array. Through the simulation calculation of image quality, the performance of optical system meets the requirements of clear imaging.

The attenuation of backscattered light through human tissue makes it difficult to measure the interferometric signal with high accuracy. We present a new method that combines the originally developed Time Domain-OCT (TD-OCT) technique with Ghost Imaging (GI) technique to detect targets at a certain depth in the scattering medium. Our method's first result shows that sample images can be reconstructed through a homogeneous mixture of 0.5% milk solution (1 cm thickness) scattering medium. Theoretical calculations show that it is possible to reconstruct images in higher milk solutions (about 20%) with optical properties close to human tissues.

In this work, we propose a low-coherence Doppler lidar (LCDL) to measure particle velocity at near-surface atmosphere. To measure particle velocity information at near-surface atmosphere, it is necessary to conduct the measurement at high frequency and resolution. Low coherence light source can satisfy this high-resolution criterion. We discuss the system efficiency to detect atmospheric echoes by theoretical analysis. In the particle velocity experiment, Doppler shifted frequency is about 5 MHz and the particle velocity calculated from the peak Doppler signal is 2.7 m/s, while minimum and maximum velocity are 1.85 and 2.92 m/s, respectively. Anemometer result shows good agreement with LCDL results.

In this study, a diffraction grating was used for generating laser parallel fringes in a camera. Phase analysis method using those laser parallel fringes were used to measure out-of-plane displacement. A green laser of line projection function, a diffraction grating and an industrial camera were used as an experimental device. Object images with laser parallel fringes projection before and after displacement were taken by the camera. Laser parallel fringes can be generated in a camera and displacement was successfully measured by phase analysis of laser parallel fringes.

In this paper, we present a wide-spectrum plug-and-play Fizeau interferometric system, which can complete precision interferometric measurement at any wavelength in the range of 600-1600 nm with a maximum measurement aperture of 150 mm. The system can be designed with multiple optical fiber input terminals, different wavelengths share only one set of interferometric system, and no components need to be adjusted when switching the working wavelength. The development of the system is helpful to accurately measure the surface profile error of coated optical elements at a specified wavelength.

Emissivity is one of the important parameters to reflect the thermal characteristics of the surface of an object. It plays a great role in the research of infrared coatings with high or low emissivity. In this paper, a novel non-contact experimental method is proposed to measure the coating’s emissivity using the dual-temperature method, and the error of the measured infrared emissivity with different base board materials is analyzed.

Optical thin-film components have known major developments over the last three decades and find now applications in many scientific fields. But it remains difficult to measure and characterize complex components. Light scattering properties are usually neglected in the characterization even though it is well-known that it can be critical for some very demanding applications where the miniaturization of optical instruments make them more sensitive to crosstalk. We present in this paper an upgraded version of a spectrally and angularly resolved scatterometer operating on a continuous spectral range from 400 to 1700 nm and reaching unprecedented levels of detection and accuracy.

This paper briefly tells the story of the importance of metrology in optics fabrication at Optimax, and highlights Wyko and Jim Wyant’s contribution to early Optimax success.

The laser rangefinder and the mapping camera have strong complementarity in the positioning of the ground target, and the combination of the two can obtain a better three-dimensional positioning accuracy of the ground target.In order to achieve highly accurate positioning of ground targets, meet the needs of large-scale surveying and mapping, and provide the required elevation control points for the stereo surveying and mapping camera, it is necessary to accurately measure the position of the laser footprint.A method for determining the position of the laser footprint based on a footprint camera is proposed. First, a low-resolution footprint camera is used to directly record the laser emission direction, and then the low-resolution footprint camera is recorded by a method based on image feature point matching. The position of the laser footprint is matched to the image of the high-resolution stereo surveying and mapping camera, and finally the direction of the emitted laser is accurately determined. This method is not related to the attitude determination error of the laser rangefinder and the internal orientation element determination of the footprint camera. Through error analysis, it can meet the 1:10 000 scale positioning accuracy requirement.

The discrete electronic energy levels in atoms and the ability to probe and control them using their interactions with electromagnetic fields have enabled a host of applications in quantum sensing and metrology, including atom-based time and frequency standards, magnetometers, and inertial sensors. Precision measurements with atoms rely on the capability to control the frequency, phase, polarization, and direction of photons used to prepare and measure quantum systems, and thus developments in near-infrared optics and photonics are critical to advancing state-of-the-art atomic sensors. In this talk, I will summarize the basic principles of atom-based quantum sensing and highlight the role of atom-photon interactions in quantum measurements. The benefits and challenges of realizing atom-based quantum sensors will be illustrated through examples from my prior research, including the development of sensitive accelerometers and gyroscopes based on cold-atom interferometers. I will discuss the critical developments in photonic engineering that are still needed to improve the performance and functionality of atom-based-quantum sensors and our research progress at UW-Madison towards addressing these needs.

A near-monostatic laser polarimeter has been designed, built, and used to measure angular Mueller matrices characterizing the polarization-dependent reflectance of materials in support of research into polarization lidar. Here we explain the system, show that it has qualitatively similar results as previous complex systems, and show example measurements for red brick, concrete, sheetrock, tar shingles, milled aluminum, and plain steel.

The ability to measure small thermal expansion of precision components can be critical to the performance of precision instruments such as optical telescopes. The methods available to measure nanometer and sub-nanometer dimensional changes on optical elements is very limited. This white paper explores the ability of the capacitance gauge to measure expansion of optical elements in the sub-nanometer range.

Complementary metal–oxide–semiconductor (CMOS) sensors may offer improved performance compared to the charge-coupled devices common in X-ray satellites. We demonstrate x-ray detection in the soft x-ray band (250 to 1700 eV) by a commercially available back-illuminated CMOS sensor using the Advanced Photon Source at Argonne National Laboratory. While operating the device at room temperature, we measure energy resolutions (FWHM) of 48 eV at 250 eV and of 83 eV at 1700 eV, which are comparable to the performance of the CCD on Chandra and Suzaku.

Photonic spin density (PSD) in the near-field gives rise to exotic phenomena such as photonic skyrmions, optical spin-momentum locking and unidirectional topological edge waves. Experimental investigation of these phenomena requires a nanoscale probe that directly interacts with PSD. Here, we propose and demonstrate that the nitrogen-vacancy (NV) center in diamond can be used as a quantum sensor for detecting the spinning nature of photons. This room temperature magnetometer can measure the local polarization of light in ultra-subwavelength volumes through photon-spin-induced virtual transitions. The direct detection of light's spin density at the nanoscale using NV centers in diamond opens a new frontier for studying exotic phases of photons as well as future on-chip applications.

Photonic Force Microscopy (PFM) uses optically trapped particles to measure fluctuation based forces and potential landscapes. This feature makes it a very soft probing technique that is well suited to investigate surface interactions with biological samples. In addition, PFMs can be used in scan mode to create surface-profiles with a resolution better than the optical diffraction limit. In this talk we present an improved intermittent contact (tapping) mode PFM and a revised data analysis for more detailed surface height profiles.

FORMA (force reconstruction via maximum-likelihood-estimator analysis) addresses the need to measure the force fields acting on microscopic particles. Compared to alternative established methods, FORMA is faster, simpler, more accurate, and more precise. Furthermore, FORMA can also measure non-conservative and out-of-equilibrium force fields. Here, after a brief introduction to FORMA, I will present its use, advantages, and limitations. I will conclude with the most recent work where we exploit Bayesian inference to expand FORMA's scope of application.

Quantum illumination is a technology that aims to improve the detection sensitivity of a target by utilizing quan- tum entangled state of light. We are studying quantum illumination using two-mode squeezed light. In quantum illumination, one light wave in a quantum entangled state is emitted toward a target during atmospheric disturbance. Therefore, it is extremely important to investigate the propagation characteristics of light waves under various atmospheric conditions toward the realization of quantum illumination. As an example of atmospheric disturbances, we have investigated the effect of uniform fog on light wave propagation in previous studies. It has been found that the effect of uniform fog on the propagation of laser light is mainly energy attenuation. Here we measure the propagation characteristics of single-mode squeezed light in a fog. We succeeded in observing the squeezed light that passed through the fog, and confirmed that the noise level of the squeezed light was degraded by the influence of the fog. It was found that the degradation of the noise level can be explained by considering that the influence of fog is mainly the attenuation of energy.

Measuring the astrometric singal of an exoplanet is an unambiguous method for determining its mass. However, Earth-like planets around Sun-like stars only cause 0.3 uas astrometric signals, which is too small for current instruments to detect. To advance these instruments, an astrometry testbed was created. It can simulate and measure equivalent signals with the use of an illuminated pinhole array and a flexurized pinhole that is translatable to 10 pm resolution. Optical distortions are calibrated with the use of a diffractive pupil. This paper presents the requirements, design, and implementation of the wide-field astrometry testbed’s light source.

Measurement of atmospheric turbulence has long been carried out using differential temperature sensors, DTS. DTS measurements of small temperature fluctuation differences between two spatially separated thermocouples can be ensemble averaged to calculate the temperature structure constant which can be used to approximate the refractive index structure constant. This technique has been widely applied and used with reasonable success in spite of several important limitations. One of the primary limitations is that the temperature structure constant alone does not fully define the refractive index structure constant; because the water vapor structure and water vapor to temperature cross correlation terms, which are much more difficult to measure, are ignored. This paper presents an initial feasibility analysis and experimental validation for a new type of refractive index structure constant sensor that is based on a compact, low cost interferometric sensor. This method is being explored as a potential alternative to DTS, because it measures index of refraction directly and thus offers the possibility of significant improvement in measurement accuracy. The paper outlines the sensor concept, its key components, and an analytical and experimental validation of the refractive index structure measurement accuracy.

Understanding how atmospheric turbulence is distributed along a path helps in effective turbulence compensation and mitigation. Phase-based techniques to measure turbulence have potential advantages when used over long ranges since they do not suffer from saturation issues as the irradiance-based techniques. In an earlier work, we had demonstrated a method to extract turbulence information along a path using the time-lapse imagery of a LED array from a pair of spatially separated cameras. By measuring the differential motion of pairs of LEDs of varying separations, sensed by a single camera or between cameras, turbulence profiles could be obtained. However, by using just a pair of cameras, the entire path could not be profiled. By using multiple spatially separated cameras, improvements can be made on the profiling resolution as well as the fraction of the path over which profiling is possible. This idea has been demonstrated in the present work by using a camera bank comprising of 5 identical cameras, looking at an arrangement of 10 nonuniformly spaced LEDs over a slant path. The differential tilt variances measured at a single camera and between all pairs of cameras have been used to obtain turbulence information. Profiling thus with elevated targets will ultimately help in a better understanding of how turbulence varies with altitude in the surface layer.

Accurate measurement of exoplanetary masses is a critical step in addressing key aspects of NASA’s science vision. Astrometry can detect and measure masses of planets orbiting the target star. However, the signal for earth-analogs is in the sub-microarcsecond regime, well beyond our instrumentation. In this paper, we study part of an astrometry error budget for the HabEx Workhorse Camera and we propose a calibration approach to reach earth-analog sensitivity.

In recent years, Meta-lens has become a new type of optical device, showing excellent performance and novel applications. The nanoantennas of meta-lens can be used to control the phase, amplitude, and polarization at well. The phase part is the most important part of the function of the meta-lens. However, so far, the phase distribution of meta-lenses has not been directly measured, which further hinders the quantitative evaluation of their performance. We have developed an interferometric imaging phase measurement system for meta-lens and meta-devices. This system can measure the phase distribution by shooting the interference pattern. The phase distribution of meta-lenses can be measured to quantitatively characterize the imaging performance. Our meta-lens phase measurement system can help for designers to optimize the design, for manufacturers to identify defects, thereby improving the manufacturing process. This work will pave the way for meta-lens in industrial applications.

Recent developments in optical trapping techniques in high vacuum allow micron-sized objects to be used as precise acceleration and force sensors with respective sensitivities of 100ng/sqrt(Hz) and 1aN/sqrt(Hz), making these sensors ideal to measure tiny forces and recoils which are the result of interactions with the environment. Due to single-electron control of the electric charge, these sensors can be made electrically neutral. This not only enables better isolation from electromagnetic noise, but also allows the measurement of electric charges on the order of 10^-4e. This levitated object is used in the search of new physics in regions of parameter space inaccessible by other techniques. This talk will discuss such sensor characterization and capabilities as well as recent results of searches for dark matter, millicharged particles bound to matter and projections for a search for short ranged interactions.

In this paper, based on the automatic detection of robot, a three-claw positioning structure is designed by using threepoint positioning technology. It can accurately locate the center position of the long and thick wall tubular equipment. According to the principle of three-point positioning technology, a kind of inner diameter measuring structure of long and thick wall tubular equipment is designed, so as to realize the accurate positioning and accurate measurement of long and thick wall tubular equipment.

The final assembly is the final and core link in the production process of the missile, and its assembly accuracy directly determines the production efficiency and quality of the product. However, the assembly of most cabins at present mainly relies on human visual inspection or with the help of measuring tools to ensure assembly accuracy, which results in poor assembly gap uniformity and low production efficiency. Aiming at the lateral assembly of small-diameter missiles, this paper proposes a method for measuring the deviation of missile assembly based on laser scanning. This method can measure the attitude deviation in the other 5 degrees of freedom except the roll angle, and finally carry out the missile assembly experiment. The experimental results show that the use of this measurement method can successfully complete the assembly of a cabin with a diameter of 160mm and a docking gap of only 0.2 mm.

Magnetic field immunity test platform is essential to qualify the reliable operation of electrical and electronic devices under strong magnetic field environment, and size of the homogenous zone, minimum field strength and field non-uniformity are the key parameters of the platform. In order to verify the validity of the platform and calibrate it, magnetic field distribution in the test zone should be accurately measured to obtain these key parameters. In this paper, a magnetic field measurement system based on Hall array is designed to measure the magnetic field distribution of a magnetic field immunity test platform. The detailed design of the measurement system is presented in this paper, including the design and calibration of the magnetic field measurement probe and the design of the Hall array and its multi-channel signal acquisition system. Experimental test is also conducted to measure the field distribution of a 0.3m/200mT test platform, which verified the effectiveness of the measurement system and calibrated the platform.

To experimentally determine the transfer behavior and the resolution limits of areal surface topography measuring instruments, numerous approaches have been suggested with the two most common ones being based on either rectangular (type ASG material measure) or sinusoidal (chirp material measure) test geometries, imaging various spatial frequencies. Each of the methods carries individual advantages and disadvantages. Here, we describe the design of a varied chirp material measure which provides sufficient amplitudes throughout a broad range of spatial frequencies. For its evaluation, two different approaches based on either geometrical fitting or a direct analysis in the frequency domain are described and compared with each other. The material measure provides a steady spectrum in the spatial frequency domain that can be evaluated with both approaches. Their advantages and disadvantages are composed to derive information for a reliable implementation that leads to a standardized evaluation routine with small uncertainty. The examination of the two methods results in an evaluation with a high statistical reliability that allows an unambiguous determination of the spatial transfer behavior.

Nano surfaces offer exciting opportunities to implement novel technologies. With their help, surfaces can be created that are very suitable as a reflection-absorbing layer. In order to be able to determine the degree of reflection and to compare it with the current methods of anti-reflection coating, a measuring system was developed which can measure the degree of reflection hemispherically. Furthermore, a simulation model was developed with which the behavior of the nano-surfaces can be examined with different parameters.

The paper discusses a new method that combines the frequency and phase domains-gated reflectometry. This approach can be applied to a fiber with artificial reflectors to measure the absolute values of the optical paths between reflection points in the fiber in the entire frequency range of the signal, including the zero frequency.

Motion Amplification is a video-processing technique that detects subtle motion and enhances that motion to a level visible with the naked eye. Motion Amplification Technology can resolve motions as small as 250 nanometers at 1 meter and can be performed live and in real-time on even a modest laptop. The process involves the use of a high definition and high dynamic range video cameras where every pixel becomes an independent point sensor creating millions of continuous data points in an instant. This essentially turns a high definition camera into a full field vibration acquisition device with over 2.3 million independent sampling locations. The technology allows the user to measure calibrated absolute displacement across the full field of view providing a time waveform and spectrum for each measured location. A comprehensive set of examples and applications will be discussed along with a live demonstration.

Mid-infrared (IR) laser spectroscopy is broadly used to study trace gas species in medical diagnostics, atmospheric monitoring, remote sensing, and industrial applications. Its capability to measure fundamental rovibrational bands due to the chemical functional groups in the most relevant gas molecules allows for high instrumental sensitivity. In this work, we used a target mid-IR wavelength laser diode to measure the concentration of CO2 gas. In addition, detecting the weak mid-IR molecular absorption bands of gases like CO2 at low concentrations requires increasing optical path lengths to be used. There are a number of methods that can potentially be used to lengthen the beam path in a spectroscopic system; the most obvious being to use a longer linear gas cell, which in some situations may suffice; however, space and volume requirements need to be considered. In this work, we used a circular multi-reflection (CMR) cell, which reflects the radiation back and forth through the sample medium multiple times greatly reducing the footprint size compared to a linear cell of equivalent path length. A CMR cell is designed and constructed so that it allows multi-reflections within the cell. The optical alignment of the cell and the convenience of changing the optical path length by adjusting its position with respect to the entering light beam are key advantages. This work will be used as the groundwork for designing an instrument for high-resolution measurement of gas abundances in planetary atmospheres.

Predictive health monitoring will require the development of advanced sensing techniques capable of providing quantitative information on the damage state of structural materials. Second harmonic generation techniques can measure absolute, strength-based material parameters which can be coupled with uncertainty models to enable accurate and quantitative life prediction. Starting at the material level, this talk will examine a combination of sensing techniques and physics-based models to characterize damage in metals. These second harmonic techniques are acoustic-wave-based, so component interrogation can be performed with bulk, surface, and guided waves using the same underlying material physics. The talk will consider applications to characterize fatigue damage, thermal embrittlement, irradiation damage, and sensitization.

Ultra-thin gaps between two metallic workpieces in assembling parts need to be measured and characterized, for determining the assembling accuracy and further ensuring the final performance of the parts. Methods such as fringe projection or optical profilers encounter the difficulties in distinguishing such micro features in several tens of micrometers. In this paper, a microscopic imaging system combining image processing algorithms is designed and developed to measure the thickness of such air gaps. Simulation studies are undertaken to validate the feasibility of the proposed method. A measuring system is then designed and developed, based on which a series of measurement experiments is carried out to verify the measuring accuracy and precision. Finally, a cylindrical assembling parts with thin gaps are measured and characterized. The proposed measuring method is useful to determine the shape of air gap and the local contact situation for assembling parts.

Aiming at the problem that infrared detectors can only measure the surface radiation of a target while flying in space. And it is difficult to obtain the hollow scale of the target. This paper designs a method for inverting the hollow scale based on the dynamic change of radiation energy. Taking a hollow sphere as an example, the relationship between the target radiation intensity and the hollow scale and time is given. Analyzed the relationship between the target radiation amount its influencing factors. On this basis, the ralationship feature between radiation and hollow scale under different time conditions is given. Through the method in this paper, hollow scale of the target can be estimated to support target detection and recognition analysis.

Lasers in this new decade are much more industrial than scientific. Lasers help produce many of the products consumers take for granted. This is especially the case with computers, smart phones, and cars but of course lasers touch many parts of other products we use every day. A laser is a tool no different than any other mechanical machine tool. The only difference is how the tool is measured. A mechanical tool can obviously be measured with a micrometer or calliper, but a laser needs a power or energy meter and an M-square measurement device to measure its size and performance. Power meter measurements are straight forward and well understood. M-square measurements have been less so. Most lasers are measured by the manufacturer in a "free space" condition. This is how it has been done for more than two decades. Given the large number of lasers in production, it is important to be able to measure these tools in the application for which they are being used. The time has come for M-square measurement to leave the "Scientific" realm and enter the "Industrial" realm so that the performance of production lasers can be quantified in their production space. This work covers the finite number of application specific M-square measurement techniques for industrial lasers which include fiber only; collimated, free space beam; post focus and pre-focus applications.

For nowadays and future resolution calibration tasks of areal-optical measuring instruments, micro structures with nanometer details, covering as most as possible of these instrument’s characteristics, are needed. Since current calibration measures do not fully satisfy all of these characteristics, we report on a newly chirped topography, that allows for the very first time for a holistic analysis of all the required attributes. To realize this highly resolved micro structure, e.g., an aberration-free laser lithography system will become indispensable in near future. Therefore, we’ve implemented a Gerchberg-Saxton based algorithm, improving any focal intensity distribution by the use of a so-called double-helix.

The unique structure of frequency combs, light sources whose lines are perfectly evenly-spaced, allows for new avenues in the measurement of optical signals. Terahertz quantum cascade laser based combs are attractive options for comb-based sensing, as they have low repetition rates and large powers per comb tooth. We will discuss how computational techniques used in concert with these combs can be used to measure the spectrum of an unknown light source|both phase and amplitude. In particular, we will discuss (a) how frequency combs can be used to recover the spectrum of arbitrary optical signals, even incoherent ones, (b) how Fourier-domain methods can be used to retrieve the phase of arbitrary combs, and (c) how terahertz combs can be used to perform high-speed, high-performance spectroscopy.

In this work we generate optical fields whose polarisation structures not only rotate about the propagation axis, but can be tailored to accelerate, independently from their spatial profiles. Here we will demonstrate how this can be achieved with orthogonal, scalar fields, represented by weighted superpositions of oppositely charged Bessel beams, through path interference with a beam-splitter. In addition to their creation, we investigate various aspects of these generated modes, such as their angular accelerating Stokes vectors and optical current or intensity transport between various local positions within the field. Finally, we present a digital analogy to measure such fields in order to reconstruct their state of polarisation via Stokes polarimetry. undefined In this work we generate optical fields whose polarisation structures not only rotate about the propagation axis, but can be tailored to accelerate, independently from their spatial profiles. Here we will demonstrate how this can be achieved with orthogonal, scalar fields, represented by weighted superpositions of oppositely charged Bessel beams, through path interference with a beam-splitter. In addition to their creation, we investigate various aspects of these generated modes, such as their angular accelerating Stokes vectors and optical current or intensity transport between various local positions within the field. Finally, we present a digital analogy to measure such fields in order to reconstruct their state of polarisation via Stokes polarimetry.

Vibrational spectroscopy is widely used in various fields where non-invasive molecular diagnosis is required, but conventional infrared and Raman spectroscopy techniques suffer from low measurement speed and therefore are used mainly for measuring static samples. Recent advancement of nonlinear frequency generation and conversion techniques allow us to develop sophisticated high-speed measurement techniques that make possible to measure dynamic phenomena with high temporal resolutions. In this talk, I introduce newly developed infrared absorption and Raman scattering spectroscopy techniques enabled by light sources with nonlinear optical techniques, including phase-controlled Fourier-transform infrared spectroscopy, rapid-scan Fourier-transform coherent Raman scattering spectroscopy, complementary vibrational spectroscopy and time-stretch infrared spectroscopy.

The proposed sensor utilizes a whispering gallery mode (WGM) resonator to measure velocity-induced non-coherent Doppler shifts in Mie-scattered light from particles moving with the air-flow. The resonator replaces the typical Fabry-Perot instrument to measure the Doppler shift. A prototype sensor was developed and experiments were carried out in an atomizing nozzle with a 25μm-diameter water-droplet-seeded air jet. Individual velocity measurements were made at the center of the nozzle, switching the flow on and off. Preliminary results show promise for the WGM-based velocity sensor concept, which would significantly reduce the size and weight of future Direct-Detection-Doppler systems for air-speed measurement, with possible applications in airborne-platform weather-monitoring and planetary studies.

High-dimensional entanglement of structured light offers the potential for noise-robust, high-capacity quantum communication protocols. However, the generation, measurement, and transport of high-quality entanglement presents some unique challenges. We demonstrate the generation and measurement of two-photon macro-pixel entanglement with a record dimensionality, quality, and measurement speed. We then discuss an experiment where we unscramble high-dimensional pixel entanglement through a commercial multimode fibre. In contrast with classical techniques, entanglement is also used to measure the transmission matrix of the fibre. Interestingly, we are able to regain entanglement without manipulating the fibre or the photon that entered it.

Currently, no bedside tool measures placental hemoglobin properties. Thus, we developed a hybrid optical/ultrasound (US) system to measure and study placental oxygen dynamics noninvasively. The system combines a Frequency-Domain Diffuse Optical Spectroscopy (FD-DOS) instrument that is capable of probing tissue as deep as 5 cm below the surface, with a commercial US device to provide synchronized tissue morphological information. Multi-layer models of photon diffusion are then utilized to reconstruct placental hemoglobin properties from FD-DOS data with morphological constraints from US. Phantom experiments, simulations, and studies in human subjects demonstrate that this instrument quantifies in vivo placental hemodynamics non-invasively.

Fourier ring correlation was recently proposed in fluorescence microscopy as an objective measure of image resolution. In this study we show that FRC has serious limitations. For several common image processing techniques, we show that FRC can be made to be systematically biased to classify objectively lower resolution images as better resolved than objectively higher resolution images. Thus, rather than providing an objective, realistic measure of spatial resolution, care must be taken in interpreting FRC-based results. In revealing some of FRC’s limitations, this study also highlights the need for a more objective, principled approach to estimating resolution.

A new measurement method called current-induced magnetic modulation spectroscopy (CIMMS), which measures the electrical impedance in a contactless manner using a high-frequency current and an induced magnetic field, has been proposed. CIMMS is to apply high-frequency minute current to a living body, measure the induced magnetic field with a magnetic sensor to obtain impedance, and measure changes such as respiration, pulse, and inflammation/collapse of lung fields. CIMMS has many advantages such as be able to measure even with clothes on, however, it cannot be realized without a magnetic sensor with high frequency and high sensitivity. Therefore, we focused on optically pumped atomic magnetometer (OPAM) as magnetic sensor used for CIMMS. OPAM has the potential to achieve ultra-high sensitivity and broadband. However, it requires a large and complicated system such as a strict magnetic shield and vibration isolation. Therefore, we developed that small and movable OPAM system that operates under unshielded condition. We also report that we achieved sensitivity of

FORMA (force reconstruction via maximum-likelihood-estimator analysis) addresses the need of measuring the force fields acting on microscopic particles. Compared to alternative established methods, FORMA is faster, simpler, more accurate, and more precise. Furthermore, FORMA can also measure non-conservative and out-of-equilibrium force fields. Here, after a brief introduction to FORMA, I will present its use, advantages and limitations. I will conclude with some recent work where we exploit Bayesian inference to expand the scope of application of FORMA.

Here we present a cold atom system, small enough to be handheld, and suitable for use in a cold atom sensor. This has been achieved by developing compact and robust components for laser cooling. Notably integrating a centilitre scale vacuum system and diffractive grating magneto-optical trap optics has been a key step in creating this compact cold atom system. The performance of these components is discussed, including the validation of vacuum by using the cold atoms to measure the vacuum pressure. Future improvements are outlined.

Quantitative phase digital holographic microscopy (QP-DHM) we have developed presents the great advantage, thanks in particular to its numerical capacity to apply both wave front correction and autofocusing, to accurately measure optical path difference (OPD) in screening mode involving multiwell cell culture plates. Experiments combining electrophysiology and QP-DHM have permitted to establish relationships between ions movements (transmembrane current) and the OPD signal. The capacity of QP-DHM to perform label-free image-based screening was validated by screening for the GABAA receptor activity expressed in HEK cells using a selection of active compounds in agonist, antagonist, and modulator modes.

Machine learning offers a powerful set of tools to make widefield endoscopic imaging more quantitative. This presentation covers our work in estimating pixel size, topography, optical properties, and molecular chromophores using structured illumination and generative adversarial networks. We aim to create a computational endoscope that will improve computer-aided detection and diagnosis.