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Many years of research and development of High Voltage Monolithic Active Pixel Sensors (HVMAPS) have culminated in the final design for the Mu3e pixel sensor. MuPix10 is a fully monolithic sensor with an active pixel matrix size of $20\times20\,\mathrm{mm}^2$ produced in the $180\,\mathrm{nm}$ HV-CMOS process at TSI Semiconductors. The pixel size is $80\times80\,\mathrm{\mu m}^2$. Hits are read out using a column-drain architecture and sent over up to four serial links with up to $1.6\,\left.\mathrm{Gbit}\middle/\mathrm{s}\right.$ each. By means of DC/DC converters and exclusive usage of on-chip biasing, MuPix10 is fully operable with a minimal set of electrical connections. This is an integral requirement by the Mu3e experiment since it enables the construction of ultra-thin pixel modules with $0.1\,$% of a radiation length per layer. First results from lab characterisation and testbeam campaigns are presented.

With feedforward neural networks, we achieved good training performance with MNIST and Fashion-MNIST datasets. But images in these datasets are simple and centered within the input space that contains them. That is, they are centered within the pixel matrix that holds them. Input space is all the possible inputs to a model.

The information contained in this chapter is the result of the collaboration between the UCM and STMicroelectronics, through an internship financed by the Spanish Ministry of Science and Universities, under grant no. EEBB-I-17-12315. The internship took place between September 1st of 2017 and March 4th of 2018. The aim of the collaboration is to integrate the Ti supersaturated material into a precommercial CMOS Image Sensor route, aiming to explore the viability of this material and the integration challenges that can arise during the fabrication and characterization process of the Focal Plane Array sensors. Most of the chapter is dedicated to the material characterization, although at the end the electrooptical characterisation of Ti implanted devices will be shown and discussed.

Fully Depleted Monolithic Active Pixels (FD-MAPS) represent a state-of-the-art detector technology and profit from a low material budget and cost for high energy physics experiments and other fields of research like medical imaging and astro-particle physics. Compared to the MAPS currently in use, fully depleted pixel sensors have the advantage of charge collection by drift, which enables a fast and uniform response overall the pixel matrix. The functionality of these devices has been shown in previous proof-of-concept productions. In this article we describe the optimization of the test pixel designs, that will be implemented in the first engineering run of the demonstrator chip of the ARCADIA project. These optimization procedures include radiation damage models, that have been employed in Technology Computer Aided Design simulations to predict the sensors behavior in different working environments., 16 pages, 13 figures, submitted to Frontiers in Physics

Image recognition is to calculate and analyze the information contained in the image, classify it or extract useful information from it. Image recognition technology based on fuzzy recognition is a new type of image recognition technology developed with the development of modern computer technology, image processing, artificial intelligence, pattern recognition theory and so on. It is an image recognition method based on traditional image recognition methods and fusing fuzzy recognition algorithm. This paper verifies the fuzzy recognition program, reads the pixel matrix of the file, and gets a relatively clear image after certain program processing. The simulation results show that the fuzzy recognition method can get more clear and accurate information in the application process of image information technology.

This work presents a digital graphic scanning (DGS) method, based on computer scanning graphics, to generate a grinding profile avoiding the difficulties appeared from the complex equations of the contact line. First the enveloping surface between the forming tool (rotor) profile and its corresponding cutting locus was developed, then based on Bresenham algorithm, the best possible pixels of the enveloping surface in the pixel matrix of screen were demonstrated using a specified color. Finally, the grinding profile data of the rotor (forming tool) were collected by scanning the pixel matrix of screen, capturing the coordinates of the indicated color of the best possible pixels. Comparing the analytical gearing envelope method and the DGS method, the feasibility of the DGS method was indicated. The DGS method was shown as a precise, rapid, efficient and stable computing tool to generate a grinding profile. In addition, such an approach can be applied in designing other similarly conjugated products such as gears, perpetual screws and milling cutters.

Interference often appears between camera and object during imaging. In this paper, an image restoration method in video sequences based on cross-correlation is proposed. A submerged object with modulated light and interference is recorded by a high speed camera. The captured data and the modulated light are regarded as input signal and reference signal, respectively. A new pixel matrix is obtained and can be restored by filtering additive noise after executing a cross-correlation operation between the signals. Experimental results demonstrate that the method can eliminate interference and enhance image quality efficiently.

International audience; RD53A is a large scale 65 nm CMOS pixel demonstrator chip that has been developed by the RD53 collaboration for very high rate (3 GHz/cm$^2$) and very high radiation levels (500 Mrad, possibly 1 Grad) for ATLAS and CMS phase 2 upgrades. It features serial powering operation and design variations in the analog and digital pixel matrix for different testing purposes. The design and verification of RD53A are described together with an outline of the plans to develop final pixel chips for the two experiments.

We conduct an extensive numerical study to single out the best performing rectangular array of evanescently coupled waveguides (discrete beam combiner) that can be used as an integrated optic beam combiner for 6-telescopes at once. We found that the performance of a discrete beam combiner only depends on the conditioning of the Visibility to Pixel Matrix (V2PM) describing it. However, we found that the condition number of V2PM pertaining to different beam combiner architectures cannot be compared. We further report on the possible input waveguide configuration of an 8-telescope discrete beam combiner featuring 8x8 or 9x9 waveguides.

Blind CFA interpolation detection，which identifies the demosaicing method used in digital camera by analyzing output images, provides many efficient tools for digital image forensics．In this paper, we proposes an approach of blind CFA interpolation detection based on the entropy of the correlative coefficients．By solving the pixel matrix equation, the CFA interpolation coefficients are calculated and the entropy of the coefficients are obtained, and they are further fed to SVM classifier to identify forgery. The experimental results show a high accuracy on blind CFA interpolation detection．Compared with existing ones，the proposed method in this paper indicates a better performance on the robnstness especially against lossy JPEG compression.

In order to segment each LED pixels from the image which is acquired by CCD and is used to brightness correction,a method based on optimal threshold segmentation with area constraint has been proposed.Based on optimal threshold method,taking prior information into account,an area constraint is introduced to restrain the range of threshold.Compared with traditional method,it is well done to avoid the LED region segmented connecting together.In the optimal threshold method with area constraint,the histogram of the captured image is generated,using the method of optimal threshold with area constraint,the optimal threshold is acquired.Finally,the optimal threshold method is used to segment the captured image.Experiments demonstrate that it is good to use this method to segment the LED pixels from the captured image,and also it can avoid the segmented region of LED pixels with a dense distribution connecting together.

Timepix3 is a high-speed hybrid pixel detector consisting of a 256 x 256 pixel matrix with a maximum data rate of up to 5.12 Gbps (80 MHit/s). The ASIC is equipped with eight data channels that are data driven and zero suppressed making it suitable for particle tracking and spectral imaging. In this paper, we present a USB 3.0-based programmable readout system with online preprocessing capabilities. USB 3.0 is present on all modern computers and can, under real-world conditions, achieve around 320MB/s, which allows up to 40 MHit/s of raw pixel data. With on-line processing, the proposed readout system is capable of achieving higher transfer rate (approaching Timepix4) since only relevant information rather than raw data will be transmitted. The system is based on an Opal Kelly development board with a Spartan 6 FPGA providing a USB 3.0 interface between FPGA and PC via an FX3 chip. It connects to a CERN T imepix 3 chipboard with standard VHDCI connector via a custom designed mezzanine card. The firmware is structured into blocks such as detector interface, USB interface and system control and an interface for data pre-processing. On the PC side, a Qt/C++ multi-platformsoftware library is implemented to control the readout system, providing access to detector functions and handling high-speed USB 3.0 streaming of data from the detector. We demonstrate equalisation, calibration and data acquisition using a Cadmium Telluride sensor and optimise imaging data using simultaneous ToT (Time-over-Threshold) and ToA (Timeof- Arrival) information. The presented readout system is capable of other on-line processing such as analysis and classification of nuclear particles with current or larger FPGAs.

A new 128 × 128 pixel matrix photodetector with a semiconductor diamond sensor is designed, fabricated, and studied. A 128 × 128 pixel ultraviolet image is detected experimentally.

This paper describes the readout components for Belle II that have been designed as integrated circuits. The ICs are connected to DEPFET sensor by bump bonding. Three types of ICs have been developed: SWITCHER for pixel matrix control, DCD for readout and digitizing of sensor signals and DHP for digital data processing. The ICs are radiation tolerant and use several novel features, such as the multiple-input differential amplifiers and the fast and radiation hard high-voltage drivers. SWITCHER and DCD have been developed at University of Heidelberg, Karlsruhe Institute of Technology (KIT) and DHP at Bonn University. The IC-development started in 2009 and was accomplished in 2016 with the submissions of final designs. The final ICs for Belle II pixel detector and the related measurement results will be presented in this contribution.

PURPOSE Experimental and clinical evaluation of a digital flat-panel X-ray system based on cesium iodide (CsI) and amorphous silicon (a-Si). METHODS Performance of a prototype detector was compared with conventional screen-film radiography (SFR) using several phantom studies. Foreign bodies, fractures, osteolyses, and pulmonary lesions were analyzed. Additionally, 120 patients were studied prospectively, resulting in 400 comparative X-ray studies. The flat-panel detector was exposed with standard dose and with a dose reduction of up to 75%. Detector size was 15 x 15 cm, pixel matrix was 1 x 1 k with a pixel size of 143 microns. Modulation-transfer function was determined to be 18% at the maximum spatial resolution of 3.5 lp/mm. RESULTS The diagnostic results achieved with the digital detector were similar to those of conventional SFR, even at reduced radiation exposure. A potential for dose reduction was observed: 50% with respect to osteoarthrosis and fractures, and 75% for determining bony alignment. DISCUSSION This new technology can be used in thoracic and skeletal radiography. A significant dose reduction is possible, depending on the suspected disease.

The silicon pixel detector of the ALICE experiment at LHC comprises the two innermost layers in the inner tracking system of the apparatus. It contains 1200 readout chips, each of them corresponding to a 8192 pixel matrix. The single chip outputs a digital Fast-OR signal which is active whenever at least one of the pixels in the matrix records a hit. The 1200 Fast-OR signals can be used to implement a triggering capability: a few details on the pixel trigger system and some of the possible applications for the event selection in p - p collisions are presented.

d i u d c L he choice of diagnostic display onitors was relatively straightforard for early adopters of picture rchiving and communication sysems. Hardware was of a single ype, cathode ray tube (CRT) techology, and was usually oriented in ortrait mode, emulating the shape f film. Monitors had high brightess, typically 60 to 100 foot-lamerts (FL), relative to other comuter and television monitors and igh refresh rates of greater than 72 z to reduce flicker visible to the uman eye. The devices themselves ere physically large, heavy, and xpensive. They generated noticeble quantities of heat while conuming relatively high amounts of ower, and their display quality deraded quickly, requiring frequent onitor replacement. Early medical-grade monitors ere available in two spatial resoutions (high and low) reflecting heir pixel matrix sizes (2K, or 048 columns by 2500 rows; and K, or 1024 columns by 1280 colmns, respectively). Medium-resoluion 1.5K monitors of 1500 columns y 1500 rows were later added to the ix. Because of the exponentially igher cost of 2K monitors comared with 1K monitors, radiology epartments typically had a combiation of a few strategically placed igh-resolution displays and many ow-resolution or medium-resoluion displays. The ACR recomended that 2K monitors be used or primary diagnosis of digital proection radiographs because a single mage could be displayed per montor in its full inherent acquired spaial resolution. The cross-sectional odalities with slice matrix sizes of 12 512 for computed tomograp

In the DEPFET pixel concept the detected incident radiation is directly sensed and amplified by a JFET integrated in every pixel cell. While the DEPFET detector principle has already been demonstrated previously on single pixel structures, we present here the first successful operation of a large 32×32 DEPFET pixel matrix as an imaging device. The matrix has been exposed to 60 keV gamma rays of a 241 Am source and has been scanned using an IR laser. The principle of operation as well as the charge collection in the structure and possible improvements are discussed.

In this paper, two digital column architectures suitable for sparse readout of data from a pixel matrix in trigger-less applications are presented. Each architecture reads out a pixel matrix of 256 x 256 pixels with a pixel pitch of 55 μm. The first architecture has been implemented in the Timepix3 chip, and this is presented together with initial measurements. Simulation results and measured data are compared. The second architecture has been designed for Velopix, a readout chip planned for the LHCb VELO upgrade. Unlike Timepix3, this has to be tolerant to radiation-induced single-event effects. Results from post-layout simulations are shown with the circuit architectures.

A new kind of silicon pixel detector with integrated amplification has been built and tested. Each pixel consists of a p -channel JFET located on a fully depleted substrate. The pixel size can be customized by using a drift-chamber-like transport mechanism in each pixel. The homogeneity of the signal response of a small matrix was investigated with a laser diode. The measured rise time and gain of the device are analyzed with a simple small signal model.

We report the approach and results on the VAST 2012 MiniChallenge 2: Bank of Money Regional Office Network Operations Forensics. Using commercial data mining, visualization and database software such as KNIME, Tableau and MySQL as well as a custom-written source vs. destination IP pixel matrix, our team of students identified suspicious IRC traffic, an attack on the firewall, a drop in the firewall connections, an attempt for sensitive information exchange and a possible Distributed Denial-of-Service attack executed partly from a host within the bank network.

This study aimed to evaluate the visibility of stents using high-resolution computed tomography (CT) acquisitions acquired with flat panel detector (XperCT, Allura series, Philips Healthcare, The Netherlands) for endovascular treatment of intracranial aneurysms. On a 24-month period, 48 patients endovascularly treated by coiling and stenting (59 stents) for intracranial aneurysms were explored by flat panel detector CT technique. A sequence of 620 2D images was acquired over an angle of 240° using a 1,024 × 1,024 pixel matrix detector within a 48-cm field of view. The images were retrospectively analyzed independently by two neuroradiologists. Evaluation criteria were percentage of visualization of the stents and stent deployment (kinking or unsatisfactory deployment of the stent). Evaluation of the stent was feasible for all the patients. Stent visibility by XperCT was overall estimated at 76% of the stent length. Difficulties to analyze the stents were related to coil artifacts but not to packing density or aneurysm location. Stent length visualization was higher when the acquisition was performed before additional coiling (P

We describe a new optical sensor for real-time 2-D solid-body vibration imaging. Exemplary data reveal previously unobserved transient phenomenon which could elucidate instability in linear dynamic systems or aid development of new non-linear dynamic sensors.

Rationale and Objectives Diffusion tensor tractography (DTT) for neural fibers of the head-and-neck region at 3T has not been reported. The purpose of this study was to evaluate the feasibility of using DTT for visualizing neural fibers in the head-and-neck region at 3T and to explore the use of this method in patients with head-and-neck mass lesions. Materials and Methods Using a 3T scanner, we obtained magnetic resonance images of the head and neck region in 5 healthy volunteers and 5 patients with head and neck mass lesions. All subjects underwent anatomic T1-weighted and diffusion-tensor imaging using a sequence with six motion-probing gradient orientations, a b value of 800 second/mm2, and a 128 × 128 pixel matrix. Fiber tracking was with the continuous tracking method. Different postprocessing parameters were investigated to optimize fiber density detection and minimize noise. In five patients with head-and-neck mass lesions, comparison of tractography results and operative findings with regards to mass and nerve relationship was also performed by two observers. Results Using the two regions-of-interest method, the greatest fiber density of presumed inferior alveolar nerves was depicted at a maximum angle of 40° and a minimum fiber length of 10 mm. DTT was successfully depicted in all 5 patients. In 4 patients, the relationship between DTT and operative findings was coincided or similar. The interobserver agreement was good. Conclusions DTT of the neural fibers in the head and neck region is feasible using a clinical 3T magnetic resonance scanner. Data from a small number of patients with head-and-neck lesions show good agreement between tractography and operative results.

This paper focuses on errors which are possible to occur in the depth measurements of range cameras. Range cameras can capture 3D information of a scene by sending out infrared light and then measuring the reflections. Wrong measurements occur at the edges of objects where the depth level changes. A depth value between the foreground and background level is measured which creates a so-called "flying pixel" when displaying the 3D points.In this paper different methods for the identification of flying pixels are presented and compared. The advantages and drawbacks of each method are discussed. Then a simple method for the correction of flying pixel errors is presented and its limitations are shown. The final method for correction is presented which is based on segmenting the pixel matrix into horizontal and vertical scanlines. After segmentation, linear segments can be identified to which the pixels can be mapped. The paper concludes with the evaluation of the presented methods to show their effectiveness.

Chicken genome AT and GC skews for individual chromosomes were visualized simultaneously using a novel method of 2-dimensional colorcoded pixel matrix. The visualizations were compared to those of human, mouse and possum genomes. A strikingly strong correlation of AT skew and GC from small to large scale in chicken genome was found, compared to the other vertebrates. Some local skew correlations were also found for the other vertebrates, but only in small genomic scale. Quantitative measures of correlation were developed, and confirmed the special characteristic of chicken chromosomes. Possible explanations for uniqueness of birds in this respect are discussed. The phylogenetic distribution and evolutionary pressures responsible for this previously unreported skew correlation warrant further study.

The main objective of this study is to understand by means of simulations which patient scatter order is significantly predominating in the photopeak window. A second goal was to qualify the difference between phantom and crystal scatter influences. Since this is dependent of the photoelectric fraction (ratio of the number of detections in the photopeak window after photo-electric effect to the total of the photopeak detections including multiple Compton and photo-electric events), several crystal materials were investigated: GSO, LSO, BGO. We also included two innovative materials: LaBr/sub 3/ and LUI/sub 3/. Simulation studies showed that only first order patient scatter is significantly degrading PET image quality. The effect of higher order scatter in the photopeak window is negligible. For crystal scatter we propose to realistically simulate the generalized natural pixel matrix in order to incorporate the aforementioned degrading factor. It was shown that this improves the image resolution.

The purpose of this study was to identify optimal magnetic resonance imaging (MRI) conditions to visualize discrete alterations of brachial plexus components, as part of a biomechanical study of minor nerve compression syndromes. A method was developed allowing direct comparison between the MRI image and the subsequently obtained matching anatomic section of the same specimen. We designed a stereotactic frame to obtain the precise orientation of the MRI plane with reference to the specimen and adapted a vertical band saw for multiplanar sectioning of cadaveric specimens. Two cadaveric upper quadrants were examined by MRI (TR 450 ms, TE 13 ms, pixel matrix 512 × 512 and FOV 23–26 cm) and anatomical slices were produced. One specimen was sectioned axially, while the second specimen was sectioned in an oblique plane corresponding to the natural longitudinal axis of the upper part of the brachial plexus. MR images and the corresponding slices exhibited a strong correlation. This correlation was checked by using vitamin A pearls as landmarks. MR images revealed more detail after the correlating anatomical slices were analyzed. The present study shows that the method is suited for direct MRI-anatomic comparison of the brachial plexus and is also proposed for application to other topographical regions.

An analytical approach using human perception has been introduced to evaluate the front-of-screen (FOS) quality of liquid crystal displays (LCDs), in particular regarding the regions of the liminance non-uniformity called "mura". The word "mura" is a Japanese term similar to "blemish" and has been adopted in English to provide a precise name for certain imperfections of the display pixel matrix surfaces that are visible when the display is in active use. The accurate and consistent detection of the mura is extremely difficult because there are various shapes and sizes of mura and the inspection results tend to depend on the inspectors during the LDC manufacturing process. We conducted a study on the quantitative evaluation of mura based on visual analysis, intending to clarify the detection method and create an automated mura inspection process. We developed an algorithm to extract and evaluate mura by using a hardware system based on a commercially available CCD camera and a PC with an image processor board. This system can successfully identify and evaluate mura. We converted the front-of-screen (FOS) images from the LCDs into distributions of luminance information, and the mura regions were distinguished from the background area. In order to further match the evaluation results of mura to human perceptions, we conducted a perception test with some expert inspectors by using pseudo mura and this approach led to categorizing "just noticeable differences" according to the varieties of mura. This paper describes the research in human perception and the approach adapting the intrinsic rules of sensory analysis to the quantitative evaluation of mura.

A 64 X 64 pixel matrix prototype has been produced at the HLL. We will describe the test system setup and present measurements which characterize the performance.

In modern ultrasonic digital sector scanners, the interaction between angulated line-of-sight vectors and a square pixel matrix results in Moiré artifacts in the image. These artifacts are a result of non-sampling of some pixels under certain conditions. The conditions which govern the appearance and progression of these artifacts are discussed, and an actual hardware demonstration is given.

Decreasing pixel size, perfection of isolation, and improved dynamic range of advanced imaging devices requires an adequate optical arrangement to check crosstalk behavior within the pixel matrix. The Fraunhofer diffraction pattern; an inherent feature of any focused circular beam, leads to unintended direct illumination of the neighbors even if accurately centered. A Simple setup has been applied to determine the beam profile focused down to the subwavelength range. We propose to characterize the beam focusing for spatial resolution tests by the first zero to-zero width independent of peak intensity. We provide an estimate of minimum requirements to be fulfilled in order to test for a given crosstalk and demonstrate their importance on filled trench-isolated pixels.

In this paper we present a conceptual model of raster graphics systems which integrates, at a suitable level of abstraction, the major features found in both contemporary and anticipated graphics systems. These features are the refresh buffer; the image creation (scan-conversion) system; the single address-space architecture which integrates the address space of the refresh buffer with those of the image creation system and the associated general-purpose computer; the RasterOp or BitBlt instructions found in some single address-space architectures; the video look-up table, and refresh buffer to screen transformations. Also included are the major components from the conceptual model of vector graphics systems which are embodied in the ACM/SIGGGRAPH/GSPC Core System. Using the conceptual model as a base, we proceed to sketch out the capabilities we have defined in a substantial addition to the Core System. The capabilities are currently being implemented as part of the George Washington University Core System.

Longitudinal relaxation times (T1) of 20 brain tumors were calculated in vivo using a whole-body magnetic resonance unit with a 0.15-T resistive magnet. Images employing standard inversion recovery pulse sequences with different intervals between the 180 degrees pulse and selective excitation pulses were compared on every point of the 256 X 256 pixel matrix. Tumor, white matter, and gray matter were sampled from each patient from the computed T1 image for T1 measurement. Astrocytomas, neurinomas, and metastatic tumors showed longer T1 values than did meningiomas. Lipomas had the shortest T1s. It is concluded that it is difficult to predict histological types of brain tumors by the measurement of T1 alone because of the wide variation in relaxation times, but measurement of T1 can be helpful in differentiating brain tumors when additional information about the patient's condition is known.

In recent years, digital radiography - especially in the form of subtraction angiography - has not only attracted attention at all radiological congresses, but has also been the particular subject of a series of symposia. Many interesting images have been shown at these meetings, documenting in chronological sequence the considerable increase in clinical and technical experience. Figure 1 a shows a recent (spring 1982) intravenous subtraction angiogram of the aorta and bifurcation. Comparison with Fig. 1 b a similar image taken in September 1981, shows the improvement of image quality achieved within less than a year here with a 512 × 512 pixel matrix.