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Human immunodeficiency virus (HIV) weakens a person’s immune system by destroying cells which are important to fighting the disease and infection. HIV is a major global public health issue with an estimated 38 million people living with HIV at the end of 2019. There is no cure for HIV. However, increased access to effective prevention, diagnosis and treatment has enabled people living with HIV to lead healthy lives. Rapid diagnosis forms an important part of the WHO’s strategy for ensuring those who are HIV positive have immediate access to care. Perhaps more critical however is that effective diagnostic testing informs individuals of their HIV status, reducing the risk of transmission. HIV prevalence within the US is disproportionately high amongst Black/African American and Hispanic/Latino American populations who often have limited access to advanced medical clinics. In this paper, we present a lateral flow device designed to detect miR-150-5p; an emerging biomarker of HIV. Based on our preliminary results shown here, we are capable of detecting the miRNA sequence at sub-ng uL-1 using colorimetric analysis, without prior amplification of the target material. We have also detailed our initial results obtained from surface-enhanced Raman scattering measurements made at the device capture line, whilst the standard deviations are large, the technique shows lots of promise for lowering the detection limit in the future.

In the process of knowing and understanding the world, the traditional media of books and paper have always played a very important role. However, with the emergence of new media and the skilled use of digital media technology, the traditional medium of book and paper media has gradually faded away in the eyes of mankind. Stereoscopic paper media is a three-dimensional paper media that can display three-dimensional virtual scenes on the display device based on the traditional paper books by using the camera of the display device to identify the logo card or the real scene, and then collect the virtual information and the real scene. In this paper, under Windows 10 operating system, the program is written by VC++ and ARtoolKit software development kit development tool, and based on augmented reality technology, virtual 3D scenes are built through 3D model modeling to achieve matching and integration with real scenes of paper books and realize 3D interaction. Based on this, a 3D interactive augmented reality system with a high degree of realism is realized. The main research contents include: customizing the paper media markers, reducing the system's misjudgment rate of the markers by combining the single-response matrix and calculating the image matching value with an optimization algorithm, realizing and tracking the recognition of the markers in real time; and optimizing the image segmentation method of the ARtoolKit software development kit, using the marker card to rotate 45° relative to the camera's position to simulate the situation when the scene has changed significantly. We use the minimum error method to calculate the gaps in real time to realize augmented reality; build a 3D model with animation effects based on the ARtoolKit software development tool and Unity development platform; accurately align the recognized markers with the virtual 3D model; add audio to the 3D model to match the content and add interactive functions to realize the control of 3D animation. Stereoscopic paper media breaks the traditional paper book book reading method, no longer just read the content of paper books, you can see and content-related virtual information on the display device of the mobile terminal, such as three-dimensional scenes, videos and so on. Stereoscopic paper media improves the reader's interest in reading and gives the reader a vivid and realistic reading experience.

Colorimetric analysis is being broadly applied in chemical sensing today; however, detection ranges and resolution limits are typically modest. In this paper, we introduce a methodology to quantify the colorimetric chemical response on a paper-based microfluidic device that enables high-resolution colorimetric detection over a broad pH range. We have achieved this by combining data from various indicators displaying sensitivity on partially overlapping small pH ranges and training machine learning classification models to the colorimetric output. The training dataset consists of images taken from the colorimetric response of three different pH indicators previously deposited on circular spots of a multilayer paper-based device, captured with a reference lab-grade camera. Instead of restricting the use of each pH indicator to their linear response regime within the RGB space, the models are trained against data spanning the entire range of pH values, from 3 to 9, in increments of 0.1, exploring the optimum combination of feature engineering and classification model to maximize the overall model accuracy. The combined analysis of image data captured simultaneously with the three indicators resulted in a pH detection accuracy above 85% with over the entire pH range with resolution down to 0.2 pH points. The demonstrated detection range and resolution are well-suited to support various applications in environmental and industrial analysis.

Colorimetric detection using microfluidic paper-based analytical devices (µPADs) and smartphones enable lowcost mobile chemical analysis solutions. However, variable illumination conditions and phone characteristics (i.e. camera hardware and software capabilities) limit the accurate interpretation and reproducibility of quantitative results. In this paper, we describe a method to automatically compensate an image captured by a smartphone camera under variable illumination conditions. By incorporating a two-step algorithm, we approximate the mobile camera picture color distribution to resemble a laboratory-grade measurement under reference illumination conditions. For every test image, the algorithm first applies a color mapping step that performs histogram matching of a set of color reference spots printed on the device to a laboratory reference measurement. After this initial correction step, a transformation matrix is computed via a least-square fit to minimize the differences between the device and the laboratory references. This matrix is then applied to the RGB channel values obtained from a µPAD to correct for illumination variations. The methodology was tested by correcting a test dataset captured using a smartphone to approximate to a calibration dataset acquired using a lab-grade camera. After correction, the relative error between the datasets fell to 10-20%, leading to an increase in classification accuracy between 12-33%. This approach enables colorimetric chemical analysis with smartphones outside the lab, removing the need to control external lighting conditions.

We show photonic responses of selected two-dimensional photonic crystals that are based on a combination of geometrical design and spatial self-similarity. Structures based on multi-layer circles, squares, and triangles are studied, finding a range of local band gaps that can be varied with the self-similarity of the photonic crystal patterns. Selected photonic modes are shown that couple to different geometrical features of the photonic crystal. The role of boundary sharpness between the two dielectric components is emphasized.

Here we report a novel approach to create tunable and reconfigurable microwave metamaterials using metal ink printing on a paper. Our approach enables easy-to-fabricate but still highly functional and tunable elements. An array of asymmetric split ring resonators was printed on a photopaper to induce Fano resonances in the microwave region (~ 10 GHz). Then, the printed paper was cut line by line and folded, so that a step height between neighboring unit cells can be created and tuned. With the varying step height between neighboring cells, our sample demonstrates significant spectral shifts and resonance tuning despite its simple geometry. Depending on the cutting direction, we observe either spectral redshift or blueshift. We explain our experimental observations based on the interactions between electric/magnetic dipoles in the neighboring unit cell. Moreover, we observe phase singularity at the zero amplitude position of the Fano resonance spectrum. The spectral phase exhibits a drastic change at this singularity point, and the phase spectrum can be also largely tuned with the geometry change in our sample. The drastic changes in phase could be very useful for various applications, such as optical sensing and beam steering.

We present an ultra-high frequency radio frequency identification based wireless communication set-up for paper-based point-of-care diagnostic applications, based on a sensing radio frequency identification chip. Paper provides a low-cost, disposable platform for ease of fluidic handling without bulky instrumentation, and is thus ideally suited for point-ofcare applications; however, result communication – a crucial aspect for healthcare to be implemented effectively – is still lacking. Printing of radio frequency identification antennas and electronic circuitry for sensing on paper are presented, with read out of the results using a radio frequency identification reader illustrated, demonstrating the feasibility of developing integrated, all-printed solutions for point-of-care diagnosis in resource-limited settings.

In this study, we demonstrate a novel wax-patterned paper-polymer centrifugal optical system for performing multiple biomedical tests. The system consists of a detector (photodiode, LED), a diagnostic disc (paper, plastic) and a DC motor, allowing monitoring of changes in real time absorbance. Here, a wax printer was used to form hydrophobic channels on paper. The diagnostic disc can be prepared by attaching wax-patterned paper to a plastic disc. After the diagnostic disc is mounted on the dc motor, the fluid first wets the wax-patterned paper by centrifugal force, slowly moves by capillary action, and the reaction proceeds in the reaction zone with enzyme and color indicator. Microfluidic devices prepared in the wax-patterned paper have several attractive features such as low cost, ease of use, disposability and portability. In addition, the centrifugal disk-based platform can provide a solution for high-efficiency analysis that can process multiple reactions in parallel and monitor reactions in real time. To demonstrate the usability of this system, we performed realtime monitoring of glucose, an important indicator of blood glucose. The detection results could be delivered with the calibration curve within 10 seconds and no complex image analysis was required. The developed wax-patterned paperpolymer centrifugal optical system is promising for clinical multianalyte point-of-care testing due to its ease of manufacture, ease of operation, low cost and high sensitivity.

Copyright: 2016 SPIE. Due to copyright restrictions, the attached PDF file only contains the abstract of the full text item. For access to the full text item, please consult the publisher's website.

There are significant challenges in global healthcare delivery at the moment. Some countries have abundant services, but are stuck with a rather nimble and expensive system that focuses on incremental innovations. Other geographies are still in need of basic tools, infrastructure and require completely different, inexpensive, and with that more disruptive solutions to satisfy their healthcare needs. Next Generation Healthcare systems with a focus on prevention / early detection and pro-active therapy will employ exponential technologies (AI, Big Data, Blockchain, Sensor Technology, Synthetic Biology, Tissue Engineering, Robotics, 3D Printing, ...) that will surely lead to significant changes in the way we experience, think about, and deliver healthcare and in which a digitally empowered patient will play a more important role. In the coming years/decades we will experience a shift from the current SICK-CARE provision to real HEALTHCARE to a focus on personal HEALTH, supported by an integration of patient generated health data with other external diagnostic and therapeutic data components creating a digital health twin as a base for prevention and patient centered precision medicine. Education and training of Biomedical Engineers needs to be adjusted to these developments focussing on solving unmet clinical needs, which requires a solid understanding of current health problems (regional, global), future technologies, economic realities and global health markets. The paper will present and discuss some of these future global innovation needs and the subsequent need for a change in the biomedical engineering curriculum that needs to include learning- (creativity, critical thinking, collaboration) and life skills (flexibility, leadership, social), as well as basic economic and entrepreneurial training — all of which are currently not taught or emphasized.

With new detectors that are capable of imaging across multiple wavelength bands, new methods need to be developed to reduce the lens count and improve performance across these multiple bands while minimizing the SWAP-c (Size, Weight, power and cost) of the system. One method that was proposed was using an update to the classical γν-ν diagram. This method which, uses instantaneous Abbe number and minimum dispersion wavelength to select materials that minimize the chromatic and thermal focal shift over the desired spectral region. A MWIR/LWIR lens was designed using this method to minimize the lens count. The lens has a continuous 3x zoom range. The lens was manufactured to determine the validity of the method that was used and to evaluate the new materials that are being developed. A comparison of the nominal design to the manufactured design is discussed. This includes a comparison of MTF performance.

We report the use of a laser-based direct-write (LDW) technique that allows the fabrication of porous barriers, which enable in-line filtration within a paper-based microfluidic device. The barriers were produced within porous substrates, namely nitrocellulose membranes, via local deposition of a photo-polymer that was subsequently polymerised by exposure from a laser source. Adjustment of the photo-polymer deposition parameters determines the porosity of the barriers, which, when carefully designed and integrated within a fluidic channel, can act as filters that enable either complete blocking, selective flow or controlled separation of particles of different sizes within a fluid travelling through the channel. We have successfully identified the fabrication parameters for the creation of barriers that allow the filtration of two different types of particles, Au-nanoparticles with sizes of 40, 100 and 200 nm and latex microbeads with sizes of 200 nm and 1 μm, dispersed within an aqueous solution. We also report the use of a variable-porosity barrier for selective separation of latex microbeads from Aunanoparticles, thereby showing the usefulness of this technique for enabling in-line filtration in such paper-based microfluidic devices.

>2 PW/sr-cm2 highly brightness Micro-MOPA was achieved. This Micro-MOPA can generate 100 mJ-class and PW/sr-cm2-class pulse with the A3 paper size footprint.100 Hz operation of the Micro-MOPA with over 2 PW/sr/cm2 was achieved. Micro-MOPA system can generate 100 mJ-class and PW/sr/cm2-class pulse with paper size footprint. However, previous repetition rate is limited to 10 Hz in spite of the oscillator and the amplifier design for 100Hz operation due to its thermal problem. However, current repetition rate is limited to 10 Hz in spite of the oscillator and amplifier design for 100Hz operation, because tThe laser diode side-pumped Nd:YAG rod of the amplifier for Micro-MOPA causes lens effect in high brightness beam operation and the focused beam from the rod causes damage to optics. We measured the thermal lens effect of the amplifier Nd:YAG rod to optimize the design of 100 Hz and PW/sr-cm2 class Micro-MOPA. Measured thermal lens focal length at 100 Hz is 0.5 m, and we found thermal lens have no significant time dependence in spite of its QCW pumping. From this result, we insert the optics with composite focal length of 0.45 m to cancel thermal focusing. On the other hand, such the optics is designed on the assumption of thermal lensing, therefore, we have to align optics with pumped amplifier. However, unaligned pumped beam already has 100mJ class energy and it is easy to break optics. To keep thermal lensing constant and to avoid this difficulty, we focused that thermal lensing have no significant time dependence and propose procedure for alignment and amplified energy control by using pumping delay timing shift between oscillator and amplifiere. From these improvements, we have demonstrated the 100 Hz operation of the Micro-MOPA with over 2 PW/sr-cm2.

In this paper, we present an industrial application of multispectral imaging, for density measurement of colorants in photographic paper. We designed and developed a 9-band LED illumination based multispectral imaging system specifically for this application in collaboration with FUJIFILM Manufacturing Europe B.V., Tilburg, Netherlands. Unlike a densitometer, which is a spot density measurement device, the proposed system enables fast density measurement in a large area of a photo paper. Densities of the four colorants (CMYK) at every surface point in an image are calculated from the spectral reflectance image. Fast density measurements facilitate automatic monitoring of density changes (which is proportional to thickness changes), which helps control the manufacturing process for quality and consistent output. Experimental results confirm the effectiveness of the proposed system.

In this work, femtosecond pulse generation in Er-doped fiber laser using graphene oxide (GO) paper based saturable absorber (SA) is presented. The article includes the characterization of optical properties of prepared SA material and detailed description of the laser performance. Stable mode-locking operation was achieved, with 515 fs soliton pulses centered at 1559 nm. The GO paper SA is characterized by 5.4% modulation depth and 155 MW/cm 2 of saturation intensity. The nearly wavelength-independent linear absorption combined with straightforward fabrication process make it a suitable material for application as a SA in low-power mode-locked fiber lasers operating in various spectral ranges.

The tone value increase in halftone printing commonly referred to as dot gain actually encompasses two fundamentally different phenomena. Physical dot gain refers to the fact that the size of the printed halftone dots differs from their nominal size, and is related to the printing process. Optical dot gain originates from light scattering inside the substrate, causing light exchanges between different chromatic areas. Due to their different intrinsic nature, physical and optical dot gains need to be treated separately. In this study, we characterize and compare the dot gain properties for offset prints on coated and uncoated paper, using AM and first and second generation FM halftoning. Spectral measurements are used to compute the total dot gain. Microscopic images are used to separate the physical and optical dot gain, to study ink spreading and ink penetration, and to compute the Modulation Transfer Function (MTF) for the different substrates. The experimental results show that the physical dot gain depends on ink penetration and ink spreading properties. Microscopic images of the prints reveal that the ink penetrates into the pores and cavities of the uncoated paper, resulting in inhomogeneous dot shapes. For the coated paper, the ink spread on top of the surface, giving a more homogenous dot shape, but also covering a larger area, and hence larger physical dot gain. The experimental results further show that the total dot gain is larger for the uncoated paper, because of larger optical dot gain. The effect of optical dot gain depends on the lateral light scattering within the substrate, the size of the halftone dots, and on the halftone dot shape, especially the dot perimeter.

EUV (Extreme Ultraviolet) lithography is one of the most promising techniques for imaging 5-nm node and beyond wafer features. Mask defects that matter are the ones that print during exposure at 13.5 nm wavelength. To support EUV development and production schedules, mask defectivity must be reduced to be at or near the optical defect levels. This task is complicated by the fact that actinic EUV mask inspectors are not currently available. In the absence of an actinic EUV inspection tool, all available methods for detecting and characterizing defects must be deployed. Based on extensive deployment and experience in the industry with optical masks, and on its record for reasonable throughput, 19x nm wavelength inspection is one of the strongest candidates available today, for the initial EUV mask inspection approach. However, there are several key challenges with 19x nm optical inspection of EUV masks. One such challenge is defect sensitivity. Another challenge is that EUV mask pattern image contrast changes as a function of pattern size and pitch. This is often referred to as “Tone Reversal”, and it is a phenomenon that occurs for specific features. It is essential to understand the impact of tone reversal on defect sensitivity and overall inspectability, specifically for image sizes and pitches at the point of tone reversal, and for those immediately on either side of the tone reversal. In this study, the relationship between base pattern contrast and absorber defect sensitivity will be discussed through the analysis of programmed defect macros (PDMs). We will also discuss whether we can influence the point at which tone reversal occurs and furthermore, whether that reversal point can be tailored to specific patterns sizes or pitches. We will demonstrate how inspection parameter optimization can be done to tailor 19x inspection to specific layer and specific groundrules to maximize both sensitivity and inspectability.

Mask manufacturers are facing major reticle metrology challenges, driving the need for cost‐effective solutions that provide tighter registration specifications and on‐device registration qualification. E‐beam mask writers’ local registration error may have a critical impact on the error contribution of the reticles to wafer overlay, as it is very local and most likely is not revealed with standard quality control schemes and sampling. The reticle error signatures are, of course, writing‐strategy‐dependent, but may also be caused by residual deflector alignment issues, thus leading to a very local but potentially critical non‐correctable overlay error on the wafer. Since the e‐beam writer strategy does not differ significantly between ArFi masks and EUV masks, we expect a similar error signature for both mask types. We will present data which demonstrates local registration errors that can be correlated to the writing swathes of state‐of‐the‐art e‐beam writers and multi‐pass strategies, potentially leading to systematic device registration errors versus design of close to 2nm. Furthermore, error signatures for local charging and process effects are indicated by local registration measurements resulting in systematic error, also on the order of 2nm. A unique measurement methodology, Local Registration Metrology, is presented that allows for dense sampling of reticle dies to characterize the local e‐beam registration error. Several thousand sites in a region of interest with length and width of a few hundred microns are measured. LMS IPRO metrology algorithms enable parallel registration measurement of all individual sites for fast and accurate metrology. High throughput allows completion of Local Registration measurement within a few minutes instead of exceeding a day of measurement time with conventional registration metrology strategies. This capability enables mask users to add local registration quality control to ensure the local wafer pattern placement error contribution by a mask is within the acceptable tolerance. In addition, based on the results of Local Registration Metrology, e‐beam mask writer corrections via feed forward can now be developed to significantly reduce local overlay error on wafer caused by the reticles.

Methods of investigation the polarization characteristics of certain types of polygraph paper were described. The most effective method for estimation of the characteristic features of optical heterogeneities of polygraph paper was proposed. The greatest sensitivity to the structural organization of optical heterogeneities of paper was observed for linearly polarized light beams with 90 degree polarization azimuth.

In this paper, we demonstrate an automatic image analysis for Micro Total Analysis Systems (μTAS) or Lab-on-Paper (LoP). By placing fiducial markers on μTAS, application can crop image and remove bending distortions, also it can perform colorimetric analysis. With previously taken photo of μTAS device with applied reagents, user can determine ie. illness presence by uploading photo into the program. In the paper was prepared μTAS sheet, algorithm for finding fiducial points and software for colorimetric analysis written in Matlab.

In this paper, we demonstrate a combination of foil and InkJet printed structures in Lab-on-Paper device. Such a device can be used to analyze a concentration of salt in water (or any other substance) by measuring the impedance of the analyte. Lab-on-Paper can perform an analysis on a microscopic volume of substances. Their advantages is low price, small size or can be easy disposable or stored. In the paper was presented manufacturing and testing of device with colorimetric pH testers and impedance measurement.

Special fiber Bragg grating (FBG) sensor embedding and interrogation schemes have been designed to capture the momentary peak pressure forces in the nip of adjacent paper machine rolls, and the spatial distribution of these nip forces along circumference and length of the roll, for production speeds of up to 2000 m/min. Additionally, this FBG sensor system measures the temperature distribution in the roll cover. FBG sensor embedment has been investigated and optimized for the implementation of pressure force measurements in various roll cover materials. These measurements enable immediate quality control during various stages of the production process. Draw Tower Grating sensor arrays, simultaneously performing spectrometric interrogation, and autonomous power supply technologies result in an extremely robust fiberoptic sensor system operating at rotation speeds of 700 rpm, equivalent to centrifugal accelerations of 300 G.

Roughness of a paper surface is particularly important in paper and board destined to be printed. Surfaces are often coated and the amount of coating and method of application used depends on the roughness of the base paper. We present a method of measure of the roughness of the paper based in the analysis of speckle pattern on the surface. Images are captured by means of a simple configuration using a laser and a camera CCD. Then, we apply digital image processing using the co-occurrence matrix, so this method can be considered as a non-contact surface profiling method, that can be used online.

A fiber optic Bragg grating (FBG) sensor and interrogation scheme has been designed to capture the momentary peak pressure forces in the nip of two adjacent paper machine rolls. The spatial distribution of these nip forces along circumference and length of the roll, for production speeds of up to 2000 m/min are investigated. Additionally, this FBG sensor system measures the temperature distribution in the roll cover. FBG sensor embedding has been optimized for the implementation of pressure force measurements in various roll cover materials. High strength draw tower grating (DTG) sensor arrays were used for the embedding process combined with spectrometric interrogation and autonomous power supply technologies. This results in an extremely robust fiber optic sensor system for operation at rotation speeds of 700 rpm, equivalent to centrifugal accelerations of 300 G. These measurements enable immediate quality control during various stages of the high-speed paper production process. © (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

There are several paradigms for color generation in reflective displays (e-Paper) including RGBW color filtering or stacked RGB or CMY. Theoretically, the highest white state reflectance and best color gamut are achieved by stacking three layers of pixels. However, stacking 3 layers induces significant optical losses especially at high resolution and typically does not allow for video operation. Therefore RGBW color filtering is currently preferred for higher resolution and single-layer e-Paper, but only provides color at 25% of the area and a maximum theoretical white reflectance of 50%. Presented herein is a new bi-primary color-system that cooperatively displays two complimentary colors inside a single sub-pixel, and therefore doubles the white state reflectance and color gamut for single-layer e-Paper. Also discussed are candidate e-Paper technologies that may be able to adopt the bi-primary color system, including possible advantages and challenges for each technology.

We have developed thin and light weight flexible EPD (electronic paper display) using QR-LPD technology. QR-LPD suits for flexible display because of its simple display structure (no TFT) and robust image holding property. Novel types of thin and light weight flexible electronic paper display are discussed. This technology can realize the "real paper like" flexible electronic paper.

Shape Memory Alloys (SMAs) are unique materials able to undergo a thermomechanically induced, reversible phase transformation. Additionally, SMA are subject to two types of fatigue, that is structural fatigue due to cyclic loading as experienced by most materials, as well as actuation fatigue due to repeated thermally induced phase transformation. The evolution of multiple material characteristics is presented over the actuation fatigue lifetime of NiTiHf actuators, including the accumulation of irrecoverable strain, the evolution of internal voids, and the evolution of the effective modulus of the actuator. The results indicate that all three of these material characteristics are clearly interconnected and careful analysis of each of these characteristics can help to understand the evolution of the others, as well as help to understand how actuation fatigue leads to ultimate failure of the actuator.

In order to consummate the management of bank paper, a new algorithm which can recognize the areas of paper tape in bundle of paper money is presented. Image segmentation is used to divide the image into several sub-blocks. Specifically, image entropy is computed in each sub-block. Experimental in different algorithms, including color training algorithm and the median filter and edge detection algorithm, demonstrates its real-time, effectiveness and robustness.

Research on affordable point-of-care health diagnostics is rapidly advancing1. Colorimetric biosensor applications are typically qualitative, but recently the focus has been shifted to quantitative measurements2,3. Although numerous qualitative point-of-care (POC) health diagnostic devices are available, the challenge exists of developing a quantitative colorimetric array reader system that complies with the ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment-free, Deliverable to end-users) principles of the World Health Organization4. This paper presents a battery powered 8-bit tonal resolution colorimetric sensor circuit for paper microfluidic assays using low cost photo-detection circuitry and a low-power LED light source. A colorimetric 3×3-pixel array reader was developed for rural environments where resources and personnel are limited. The device sports an ultralow-power E-ink paper display. The colorimetric device includes integrated GPS functionality and EEPROM memory to log measurements with geo-tags for possible analysis of regional trends. The device competes with colour intensity measurement techniques using smartphone cameras, but proves to be a cheaper solution, compensating for the typical performance variations between cameras of different brands of smartphones. Inexpensive methods for quantifying bacterial assays have been shown using desktop scanners, which are not portable, and cameras, which suffer severely from changes in ambient light in different environments. Promising colorimetric detection results have been demonstrated using devices such as video cameras5, digital colour analysers6, flatbed scanners7 or custom portable readers8. The major drawback of most of these methods is the need for specialized instrumentation and for image analysis on a computer.

This Conference Presentation was recorded at SPIE Photonics West 2017 held in San Francisco, California, United States.

For the last eight years, the solar industry has experienced annual growth of over 40%. Concerns over the rising costs of conventional energy, as well as its environmentally damaging effects, have been driving this vigorous investment in solar energy. Now, with grid parity almost upon us, the solar industry is reassessing what it will look like as a commoditized, mainstream power source. Do the best opportunities for solar lie with a centralized or decentralized model of production? What are the most bankable PV technologies? How can costs be cut and efficiencies improved to take things to the next level and make that last push to reach grid parity? In this paper, we will examine Solaria's LCPV technology and approach to the future of solar power.

We built a hyperspectral imaging apparatus using middle-infrared light of 8–14 μm, which has a strong ability to identify organic materials, and attempted visualization of the distribution of organic materials that could not be identified by a naked eye. For this purpose, we utilized a low-cost bolometer camera (Nippon Avionics co., ltd. C100V, Japan) for its easy availability rather than an expensive mercury cadmium telluride (MCT) array sensor. To compensate for the low sensitivity of this bolometer, we adopted a Fourier-type spectroscopic system (Aoi Electronics co. ltd., Japan) using an imaging interferometer devised by the Kagawa University, Japan; this interferometer has higher light-utilization efficiency than Michelson interferometers, which are used in popular interferometry techniques. In this study, 4 types of adhesives, 9 types of varnishes and more than 50 types of inks were put on Al plates of size 10 cm × 10 cm and were used as samples. Glossy paper for printing photos with an inkjet printer was also used as a sample. A 300 °C black body of size 15 cm × 15 cm was used as a light source. Spectra of 320 × 240 points were measured at a wavelength resolution of approximately 9 cm−1. The mirror was scanned only once. The measurement time was approximately 30 s. Hyperspectral images of adhesives, varnishes and inks on Al plate and paper were successfully measured. Spectra over a 5 × 5-pixel neighborhoods were averaged, and the averaged spectra were compared with those measured by a commercially available Fourier transform infrared (FTIR) spectroscopy. The averaged and measured spectra had absorption peaks at the same wavelengths. Furthermore, by analyzing the measured spectra, the distribution of substances invisible to the naked eye was visualized. Our results show that if low-absorbance organic materials are put on a high-reflectance surface such as an Al plate, the middle-infrared hyperspectral imaging could be measured using a bolometer. Additionally, hyperspectral imaging of high-reflectance paper, such as glossy paper, could also be measured. Because a bolometer camera is much cheaper than an MCT array, hyperspectral imaging with such a camera has many potential applications. Moreover, an imaging interferometer, with its high efficiency of light utilization, is very suitable for the purpose.

Given monochromatic infrared LED (light emitting diode) device best modulation current, frequency, distance to reach its maximum output power and improve the measuring accuracy of quantifier. Design a wavelength of 2.12 μm, 1.89 μm monochromatic infrared emissions and detection optical path, two monochromatic infrared lights which the photo source sends out after transmits the analyte across the same point to achieve the same point detection and improve the accuracy of the measurement. After the paper samples basis weight have carried out nondestructive testing, which was improved from the aspects of structure. By using the light source, halogen tungsten lamp, filter wheel, electrical equipment can be saved, and it can simplify the measuring system. The experimental results show that when measuring the thickness of the paper in the range, the relative error is within 1%.

Fiber optic pressure sensors were integrated into the grinding plates of an operational paper pulp mill for real-time monitoring of the pulp grinding process. On-line system monitoring will allow smart, active control of the grinding plates thereby improving the quality and consistency of the pulp produced. Sensors were constructed and calibrated for use in the harsh environment of an operating paper pulp grinder. The sensors were 1.65mm in diameter including titanium housing, and were installed directly into the grooves of the grinding plates. The sensing elements were flush-mounted with the wall and exposed to the wood pulp slurry. Nine sensors were calibrated up to 1000psi. During operation, pressure was sampled at 1.0MHz, and pressure spikes up to 175psi were observed. Pressure pulses measured are due to the relative motion between the grooves and channels on two pulp grinding plates. The consistency, size distribution, and quality of paper pulp exiting from the grinder are directly related to the distance between the channels on the two rotating elements. The pressure pulses produced are also proportional to the distance between channels. Therefore, by monitoring pressure fluctuations, grinding elements can be dynamically controlled thereby producing a "smart mill."

Technological development is seen as one of the fundamental forces in shaping the modern economies. The effects and the role of technological development are also central questions in many issues of environmental protection. This paper presents the results of a life cycle assessment study of the Finnish pulp an paper industry. Three comparative scenarios are drawn. Two scenarios describe the technological levels and production volumes of 1993 and 1997. A comparison scenario with the production volumes of 1997 and the technological level of 1997 describes the effects avoided by improvements. The results demonstrate that technological development has had considerable effects on the material flows of the industry within a relatively short period of time. Changes in most material flows result from various improvements. The environmental performance of the industry has been improved by both changes in operative practices as well as capital investments. The study fails to describe some aspects of realized developments and thus indicates that factors connected to technological change are highly problematic for LCA modelling.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Non-invasive measurement of paper porosity is an important problem for papermaking industry. Presently used techniques are invasive and require long time for processing the sample. In recent years optical coherence tomography (OCT) has been proved to be an effective tool for non-invasive study of optically non-uniform scattering media including paper. The aim of present work is to study the potential ability of OCT for sensing the porosity of a paper sample by means of numerical simulations. The paper sample is characterized by variation of porosity along the sample while numerical simulations allow one to consider the samples with constant porosity which is useful for evaluation of the technique abilities. The calculations were performed implementing Monte Carlo-based technique developed earlier for simulation of OCT signals from multilayer paper models. A 9-layer model of paper consisting of five fiber layers and four air layers with non-planar boundaries was considered. The porosity of the samples was varied from 30 to 80% by varying the thicknesses of the layers. The simulations were performed for model paper samples without and with optical clearing agents (benzyl alcohol, 1-pentanol, isopropanol) applied. It was shown that the simulated OCT images of model paper with various porosities significantly differ revealing the potentiality of the OCT technique for sensing the porosity. When obtaining the images of paper samples with optical clearing agents applied, the inner structure of the samples is also revealed providing additional information about the samples under study.

In present work the capabilities of an optical coherence tomography (OCT) setup to visualize paper structure are analyzed by means of Monte Carlo-simulation of the OCT images. The OCT setup at 910 nm was considered. Efficiency of several different optical clearing agents (OCA) for increasing the quality of the obtained images was studied. A multilayer non-planar edged paper model was developed for the characterization of a paper sample and simple recovery of its parameters. The effect of the setup parameters on the obtained OCT-images was studied. It was shown by comparison with the experimental data that the developed model provides satisfactory resemblance of simulated and experimental images of papers sample structure.

The proliferation of digital information is leading to a wide range of applications which make it desirable to display data easily in many locations, all changeable and updateable. The difficulty in achieving such ubiquitous displays is the cost of signage, the cost of installation, and the software and systems to control the information being sent to each of these signs. In this paper we will talk about a networked system of such signs which are made from gyricon electronic paper. Gyricon electronic paper is a reflective, bistable display which can be made in large web sheets at a reasonable price. Since it does not require a backlight nor does it require power to refresh the display image, such technology is ideal for making signs which can be run on batteries with extremely long battery life, often not needing replacement for years. The display also has a very broad illumination scattering profile which makes it readily viewable from any angle. The basic operating mechanism of the display, its manufacturing technique, and achieved performance will be described, along with the description of a networked solution using many such signs controlled with system software to identify speakers and meetings in conference rooms, hospitality suites, or classrooms in universities. Systems will also be shown which are adapted to retail pricing signage and others which can be used for large format outdoor billboards.

The paper presents benefits of optical time-of-flight spectroscopy for the pulp and paper characterization. A semiconductor pulse laser and a streak camera as the photodetector were utilized in experimental part of research described in this paper. Distribution of the time of flight of photons through various kinds of wood pulp (e.g. pulp after mechanical treatment coming both fi-om tree species giving hard and soft wood and pulp after thermo-mechanical treatment) was measured. The pulp samples used in the measurements had consistency ranging from 0 to 5% of dry mass in the suspension. The influence of additives (kaolin, talc and calcium carbonate) present in the suspension on the time of flight distribution of photons was studied as well. Finally, dependence of the time of flight of photons through various kinds of the paper (i.e. newspaper, copy paper, and tissue) on the thickness of the sample was investigated.

The refractive index of paper was determined by measuring the propagation delay of photons in optically cleared paper boards. The determination was based on the assumption that photon propagation delay achieves minimum value as the paper is optimally cleared. The measured paper sheets was made from elemental chlorine-free market pulp, i.e. fully bleached, unbeaten, softwood kraft pulp. Nine different clearing agents with a refraction index between 1.329 and 1.741 were eLuperimented with. According to the streakmem measurements, the refractive index of the test paper was 1.557.

This paper considers the classic non-causal state information problem in channel coding where non-causal channel state knowledge at the transmitter, which is also called the Gel'fand Pinsker problem. This paper determines Lagrangian dual expression for this problem, illustrating that Costa's dirty paper coding result can be replicated using the dual-problem methodology.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Phenylketonuria is a genetic disease, which causes the metabolization disorder of phenylalanine, this disorder would damage the neural system of infants as a result of the accumulation of phenylalanine in blood. Therefore, it is of great importance to diagnose and treat phenylketonuria as early as possible for newborns. The aim of this paper is to develop a fluorescence detection system to measure blood phenylalanine concentration of new-born infants. In this design, a high luminance ultraviolet LED is used for excitation source, and a kind of bifurcated optical fiber assembly is applied for conduction of light. The excitation source is filtered and coupled into quartz fibers of the bifurcated fiber assembly for conduction of light to excite the fluorescence of phenylalanine in blood sample. The collected fluorescence is transmitted along the glass fibers of the assemblies and coupled to a photomultiplier tube. The fluorescence is filtered with 470~500 nm band-pass filter to subdue scattered excitation light and to limit the spectral width of the detected fluorescence. By the comparison with a standard instrument, the new system with low power consumption, low cost and small size is also proven sensitive and accurate, which meets the demand of clinical phenylketonuria screening.

Due to the increased used paper collection rates in Western Europe, more recycled fibre will be used in the manufacture of paper. This will affect both the environmental and economic performance of the pulp and paper industry. The potential for the increase of the collection rate varies significantly in different countries in western Europe. In some countries the collection rate is already close to 70% (Austria, Germany) and in others it is around 45% (Italy, United Kingdom). With the increased demand for recycled fibre also the collection will increase. When the collection of waste paper is increased something has to be done with the collected paper. Different utilisation modes results in different emission profiles. They also have different economic consequences. In this article the environmental and economic impacts of an increased paper collection rate are studied with three alternative scenarios. These scenarios are drawn using a dynamic material flow modelling such as Joined Time Projection (JTP). The results show, that a clear trade off between harmful environmental impacts and economic benefits exists.

There are several important standard laboratory experiments for determining the quality of produced paper in the paper making industry. To know the quality is essential since it defines the use of paper for various purposes. Moreover, customers are expecting a certain degree of quality. Many of paper printability tests are based on off-line visual inspection. Currently these tests are done by printing test marks on a piece of paper and then observing the quality by a human evaluator. In this report visual inspection on paper by machine vision is discussed from a point of off-line industrial measurements. The work focuses on the following paper printability problems: missing dots (Heliotest), print dot density, unevenness of printing image, surface strength (IGT), ink setting, linting, fiber counting, and digital printing. Compared to visual inspection by human evaluation, automated machine vision systems could offer several useful advantages: less deviations in measurements, better measurement accuracy, new printability parameters, shorter measurement times, less manpower to monotonic measurements, many quality parameters by one system, and automatic data transfer to mill level information systems. Current results with paper and board samples indicate that human evaluators could be replaced. However, further research is needed since the printability problems vary mill by mill, there is a large number of various paper and board samples, and the relationships between off-line and on-line measurements must be considered.

This paper studies the correlation between the time-of-flight (TOF) of laser pulses and paper density, basis weight, thickness and the beating of pulp. Paper samples made from unbeaten and beaten pulp were compressed from 500kg/m3 to 1100kg/m3 and laser pulses were shot through them during pressing. Changes were observed in the thickness of the samples and in the TOF of the laser pulses. The results show that TOF decreases during comrpession. This indicates that distances between the various scattering surfaces decrease. This phenomenon becomes more pronounced as the basis weight increases. The beating of the pulp before papermaking increases the number of scattering surfaces, thus broadening the laser pulse and causing delay. These two effects cannot be separated with the equipment used. Papers made from different pulp types each have unique delay constants.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The UK National Quantum Technology Hub in Sensors and Metrology is one of four flagship initiatives in the UK National of Quantum Technology Program. As part of a 20-year vision it translates laboratory demonstrations to deployable practical devices, with game-changing miniaturized components and prototypes that transform the state-of-the-art for quantum sensors and metrology. It brings together experts from the Universities of Birmingham, Glasgow, Nottingham, Southampton, Strathclyde and Sussex, NPL and currently links to over 15 leading international academic institutions and over 70 companies to build the supply chains and routes to market needed to bring 10–1000x improvements in sensing applications. It seeks, and is open to, additional partners for new application development and creates a point of easy open access to the facilities and supply chains that it stimulates or nurtures.