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This Master’s thesis work is about the conditions that can affect the identification of defects in lithium-ion batteries. In lithium batteries, there are cathode and anode, which are separated with electrically insulative but ionically conductive electrolytes and separators. The cathode consists of aluminum foil, and the anode consists of copper foil. During the production of the batteries, these foils are being coated with active materials. Unfortunately, some defects such as scratches, misshape, marks, or spots can occur during the coating, and these defects harm the batteries’ performance. To ensure a good performance of the batteries, these defects have to be detected and identified. Today, these defects can be detected with a camera that scans the foils. To detect all the defects, even smaller marks, and dots, a new high-resolution sensor was investigated. The new sensor called Contact Image Sensor that acquires the raw information of the light and converts it into electrical signals was used. In other words, all the objects reflect the light, and the Contact Image Sensor captures the reflected light from the objects. By investigating the light, illumination time, and the contrast of the objects, it is possible to make the defects more visible. Furthermore, this thesis covers the speed of the coated foils passing the sensor. Since the production of the batteries should be time and cost-efficient, the speed can be high, but the sensor should have enough time to scan clear images. In this Master’s thesis work the implications of different sensor resolutions and contrast settings in a roll-to-roll process were studied, considering the speed of the process vs identifying defects (such as scratches and misshapes). It has also been studied if the light conditions, under normal circumstances, have a substantial impact on this trade-off. The result has been promising. Since the sensor has an internal resolution, a limited scanning area, and a scanning frequency, the speed will be limited by a maximum illumination time. But as long as the illumination time is under the maximum, the speed, in this case, does not matter. The maximum illumination time is different for different speeds. Furthermore, the results clearly show that high resolution, maximum allowed illumination time for each speed, and lower speeds, provide the best conditions for finding and identifying defects. However, there comes a price for the illuminated foil. The price is that the bright light can lead to overexposed foil, i.e., the part of the foil without coating will be exposed to too much light. This can create problems if damage to the foil is to be identified. Therefore, a more nuanced light that balances the contrast of the coating part and the foil is recommended. Det här masterexamensarbetet handlar om förhållanden som påverkar identifieringen av defekter i litiumjonbatterier. Litiumbatterier består av katod och anod som separeras av elektriskt isolerande men joniskt ledande elektrolyt och separatorer. Katoden består av aluminiumfolie och anoden består av kopparfolie. Under tillverkningen av batterierna beläggs dessa folier med aktiva material. Tyvärr uppstår det ibland skador i beläggningen så som repor, missbildning, märke eller fläckar. Dessa defekter försämrar batteriets prestanda. För att säkerställa att batterierna fungerar felfritt måste dessa defekter upptäckas och elimineras. Idag används kamera som skannar folierna för att hitta defekter. För att upptäcka samtliga skador, bland annat mindre märken och fläckar, övervägs en ny högupplöst sensor. En ny sensor, så kallad Contact Image Sensor, som tar in ljuset och omvandlar det till elektriska signaler undersöks. Med andra ord fångar Contact Image Sensor det reflekterade ljuset från objekten. Genom att undersöka ljusets styrka, belysningstiden och kontrast är det möjligt att göra defekterna mer synliga. Vidare omfattar detta examensarbete hastigheten hos de folierna som passerar sensorn. Under en tids- och kostnadseffektiv produktion av batterier kan hastigheter av foljer vara höga, men sensorn måste ha tillräcklig tid och utrymme att skanna tydliga bilder. Påföljden av olika sensorupplösningar och kontrastinställningar i en roll-to-roll-process har därför studerats i detta examensarbete med hänsyn taget till processens hastighet kontra identifieringen av defekter (såsom repor och missbildningar). Det har också studerats om ljusförhållandena har, under normala omständigheter, en väsentlig inverkan på denna avvägning. Resultatet har varit lovande. Med anledning av sensorns interna upplösning, dess begränsade skanningsområdet, samt skanningsfrekvensen, kommer hastigheten att begränsas av en maximal belysningstid. Men så länge belysningstiden är under maximalt kommer hastigheten inte ha någon betydelse. Denna maximala belysningstid är olika för olika hastigheter. Vidare framgår det tydligt i resultatet att hög upplösning, maximal tillåtna belysningstiden för respektive hastighet, och lägre hastigheter, ger bästa förutsättningar för att hitta och identifiera defekter. Dock kommer ett pris för det upplysta beläggningen av foljen. Priset är att det ljusa ljuset kan leda till överexponerade folje, dvs där den delen av foljen som saknar beläggning utsätts för mycket ljus och kan bländas. Detta kan skapa problem om skador på foljen ska identifieras. En mer nyanserad ljus som balanserar kontrasten av beläggningen och foljen kan därför rekommenderas.

One of the limiting factors for industrial application of additive manufacturing (AM) is the lack of geometrical accuracy of manufactured parts. To improve precision, non-contact sensors should be integrated into AM machines, capable of performing in-situ inspection of the part and being able to detect and compensate for the actual geometrical errors. A non-contact digitizing system is proposed in this work for the inspection of the deposited material layers, based on a Contact Image Sensor (CIS) extracted from a commercial flatbed paper scanner. In order to integrate this sensor in an AM machine, a methodology was developed that includes the sensor operation analysis, the design of the necessary hardware and software to be externally controlled and the subsequent processing of the captured images. Results prove that the CIS sensor can be integrated in any device external to the original scanner.

Graphical abstract, A compact beam-position monitor was constructed using a linear contact image sensor attached to a plastic scintillator and tested using a 230 MeV proton beam. The results indicate that the beam position can be obtained in real-time, and the beam position with a precision of up to 0.03 mm. The compactness and high precision of the device hold considerable potential for it to be used as a beam-position monitor and offline, daily quality assurance monitor in hadron therapy. • The method can provide a high precision and high resolution beam position for flash irradiation in particle therapy in real-time. • The method using contact image sensor with scintillator does not require a long focal length for camera and it is free of image distortion. • The method can be integrated into medical particle accelerator for feedback control and daily quality assurance.

A new and inexpensive concept for MMW imaging is presented in this study. The new concept is based on a glow discharge detector (GDD) row and a commercially inexpensive contact image sensor (CIS). The GDD was found to be a sensitive MMW radiation sensor and was used as a pixel in MMW focal plan arrays (FPA). The up-conversion detection method is based on detection of changes in luminous intensity of the GDD pixel due to the interaction with MMW radiation. A row of 44 GDD pixels were attached to a commercial CIS forming a MMW row sensor (MRS). The CIS samples the GDD row emitted light using a 1728 photo sensor array, then converts the analog data to digital data using a standard ADC board. In order to construct a full 2D MMW image of an object, the MRS is laid on top of a computerized X/Y translation stage similar to the mechanism of scanners and copy machines. A digital lock-in amplifier software algorithm is used to improve the sensitivity and SNR of the MRS signals. The entire system will be controlled using LabVIEW software.

The degree of defilement of the banknotes to some extent determines whether the banknotes can continue to circulate. How to accurately identify the dirtiness of banknotes is a major issue facing financial instruments. To solve this problem, we use a contact image sensor to collect double-sided reflection images of banknotes under red light, green light, blue light, and infrared light, and at the same time, collect images of banknotes under transmission of green light and infrared light. By using an image processing method to extract the banknote images, and then analysing the images formed by the various stain levels of the banknotes irradiated by various light sources, it is finally decided which kind of light source banknote images are input to the convolutional neural network. We process the classified training samples and test samples in the above manner, and we will get the training samples and test samples of the banknote images. Using the training sample to train our convolutional neural network, we will get the banknote dirt recognition classifier we need. Then use the test sample to test on this classifier, we will get the recognition effect of our trained classifier. The test results show that our designed convolutional neural network classifier is very accurate for identifying the dirtiness of banknotes.

A new design scheme of multispectral criminal detector is proposed to overcome the problem that the existing hyperspectral criminal detection instrument possess tedious extraction of physical evidence information, the expensive equipment and so on. First, CIS(Contact Image Sensor) is selected to emit five sources of red, green, blue, infrared and ultraviolet, and so the image information produced by light source is obtained. Then, the high precision image information and high-speed data transmission are acquired by FPGA. Finally, the Gabor filter algorithm is used to extract feature information and support vector machine training for realizing the extraction of fully automated material evidence. Experimental results show that the output resolution of the proposed design scheme is as high as 1200x2400DPI, and material evidence extracting takes 12.5 seconds, furthermore, the accuracy rate of automatic material evidence recognition is as high as 92%. The proposed design scheme can quickly and accurately realize the fingerprint, alter or cover the handwriting automatically.

An inexpensive hand-held device for analysis of colorimetric sensor arrays (CSAs) has been developed. The device makes use of a contact image sensor (CIS), technology commonly used in business card scanners, to rapidly collect low-noise colorimetric data for chemical sensing. The lack of moving parts and insensitivity to vibration allow for lower noise and improved scan rates compared to other digital imaging techniques (e.g., digital cameras, flatbed scanners); signal-to-noise ratios are a factor of 3-10 higher than currently used methods, and scan rates are up to 250 times faster without compromising sensitivity. The device is capable of real-time chemical analysis at scan rates up to 48 Hz.

For the shortcomings of complex equipment, cumbersome operation and high cost when using CCD to detect criminal investigation material, an instrument of criminal investigation based on CIS (Contact Image Sensor) is designed. First, because of strong anti-interference and high sampling accuracy, the CIS is used to sample image information. Then, use Gabor algorithm for image filtering to meet the sampling image resolution of 1200 DPI. Finally, extract the physical evidence-related features Information to finish material detection of the criminal investigation (fingerprint matching, counterfeit identifying and covered character recognizing etc.).

The paper presents a novel contact image sensor (CIS) to monitor the local scour process around a model pile in water flows. The CIS is an optical sensor that tracks the evolution of the in...

A method of the image acquisition based on digital signal processor (DSP) is introduced. DSP, complex programmable logic device (CPLD) and contact image sensor (CIS) are combined in the hardware design, and the time-sequence analysis of the image acquisition process is also presented. Practical application indicates that this method has high accuracy and is rapid enough to satisfy the requirement of real-time acquisition.

We designed a compact and large depth of field image scanner targeted for auto document feeders (ADF) by using a compound eye system design with plural optical units in which the ray paths are folded by a reflective optics. Though we have previously proposed the principle concept, we advance the design using a free-form surface mirror to reduce the F-number for less illumination energy and to shrink its optical track width to 40 mm. We achieved large depth of field (DOF) of 1.2 mm, defined as a range exceeding 30% modulation transfer function (MTF) at 300 dpi, which is about twice as large as a conventional gradient index (GRIN) lens array contact image sensor (CIS). The aperture stop has a rectangular-shaped aperture, where one side length is as large as 4.0mm for collecting much light, and another side length is as small as 1.88mm for avoiding interference of folded ray paths.

Fitness classification is a technique to assess the quality of banknotes in order to determine whether they are usable. Banknote classification techniques are useful in preventing problems that arise from the circulation of substandard banknotes (such as recognition failures, or bill jams in automated teller machines (ATMs) or bank counting machines). By and large, fitness classification continues to be carried out by humans, and this can cause the problem of varying fitness classifications for the same bill by different evaluators, and requires a lot of time. To address these problems, this study proposes a fuzzy system-based method that can reduce the processing time needed for fitness classification, and can determine the fitness of banknotes through an objective, systematic method rather than subjective judgment. Our algorithm was an implementation to actual banknote counting machine. Based on the results of tests on 3856 banknotes in United States currency (USD), 3956 in Korean currency (KRW), and 2300 banknotes in Indian currency (INR) using visible light reflection (VR) and near-infrared light transmission (NIRT) imaging, the proposed method was found to yield higher accuracy than prevalent banknote fitness classification methods. Moreover, it was confirmed that the proposed algorithm can operate in real time, not only in a normal PC environment, but also in an embedded system environment of a banknote counting machine.

We report a novel wide field-of-view (FOV) scanning endoscope, the AnCam, which is based on contact image sensor (CIS) technology used in commercialized business card scanners. The AnCam can capture the whole image of the anal canal within 10 seconds with a resolution of 89 μm, a maximum FOV of 100 mm × 120 mm, and a depth-of-field (DOF) of 0.65 mm at 5.9 line pairs per mm (lp/mm). We demonstrate the performance of the AnCam by imaging the entire anal canal of pigs and tracking the dynamics of acetowhite testing. We believe the AnCam can potentially be a simple and convenient solution for screening of the anal canal for dysplasia and for surveillance in patients following treatment for anal cancer.

A method to identify scanner models that had been used to forge low-level counterfeit currencies was proposed in this study. The method identified a scanner model by characterizing differences between hologram images that exist in low-level counterfeit currencies. Twenty scanners of 18 different models were used to make samples of hologram images used in this study. The method was divided into two steps: identification of capturing conditions and identification of the scanner model. The first proposed protocol used correlations of spatial distribution of brightness to identify capturing conditions. A second proposed protocol used correlations of color distributions to identify a scanner model. The effectiveness of the protocols was demonstrated with numerical methods and sample images. The preliminary study revealed that it is necessary to consider the orientation of the holograms when the scanner models were identified, but 180° rotations can be ignored. Moreover, it is necessary to consider position in the main scanning direction of the bed for charged-coupled-device scanners. The demonstration showed that the first protocol could correctly identify the capturing conditions of almost all hologram images. However, one image could not be identified correctly; the protocol could distinguish images captured by charged-coupled-device scanners and those captured by contact image sensor scanners if the hologram was placed on the right or left edge of the scanner bed, but could not distinguish them if the hologram was placed on the inside. The demonstration also showed that the second protocol could correctly identify scanner models of all hologram images.

In this paper, an image acquisition and processing system based on contact image sensor (CIS) and DSP is introduced, which captures images of prints from CIS and processes images using DSP. Based on this, the captured image can be sent to PC by network. The hardware design, data transmission and network communication are discussed. Based on polling caching mechanism, high-performance DSP and rich communication interfaces, the system has an advantage of high speed, good robustness and good expansibility.

In this paper, one experiment teaching case design for photoelectric sensor signal processing is proposed, by using the filtering of contact image sensor (CIS) as a example. The signal with the noise of CIS the scanning output signal will affect the authenticity of the image, so based on the analysis of the CIS output signal noise, the design of two-dimensional wavelet transform for the reconstruction of the image by the CIS output signal of the filter which is based on Xilinx FPGA dsp48 structurally and realized the accelerated calculation through the FIR IPCore, will be introduced in this paper. From the experiment, this algorithm can reduce most of the noise in reconstructed image to ensure reconstructed image can be complete and clear.

In this paper, we present a fast algorithm for country classification of banknotes. The algorithm can be used as an initial step for conventional banknote classification methods developed for a single currency in multi-country environment. We assume that the input image is a Contact Image Sensor (CIS) scan image with de-skewing and Region of Interest (ROI) extraction. In the training process, after size normalization we extract eigenimage for a banknote group based on overall context similarity. With the dominant eigenimage of each banknote group, we compute correlation metrics between the dominant eigenimage and test images. We tested the algorithm with four currencies: USD, KRW, CNY and EUR. The proposed method shows 100% accuracy and it took about 0.37ms for a banknote.

The current-voltage characteristics of a p − i − n a-Si : H contact image sensor under dark and illuminated conditions have been simulated by solving the Poisson's equation and the continuity equations, and the results are correlated with the experiments. The dependence of the dark and photo-currents on the parameters such as the density of states in the gap, intrinsic layer width, dopant concentrations of p + layer and n + layer are discussed.

A controller for contact image sensor (CIS) is designed based on CPLD and VHDL. The controller includes a controller of timing driver for CIS, a controller of analog-to-digital converter, a storage of data, a switch of memory bus and a interface to MPU. The simulated waveform diagram of VHDL program is also provided in the paper. The controller works well in the paper currency sorting machine.

This paper describes novel feedback reset circuits for a contact image sensor (CIS) system using phototransistors as sensing elements. Simulated results of the proposed circuits indicate that the dynamic range defined by the difference of the bright output saturation level and dark level can be improved, which in turn enhances the sensed image quality

A contact image sensor is used as the position sensor for real-time control of a magnetic suspension system. The system contains a line light source and a linear photosensor array. The object to be measured is suspended between the light source and the sensor array. It acts as a mask to shade and shape of the light reaching the sensor array. No advanced optical system for light focusing and calibration is necessary. The mechanical adjustment of the measurement system is not critical, and the method is relatively economical. Results show that the sensor system is effective in real-time measurement systems for magnetic suspension control applications. >

In this paper, we describe a sophisticated scanning system, which is based on an advanced Contact Image Sensor (CIS), used to scan the image and to verify the authenticity of the checks. The entire structure works on the FPGA platform, and the CIS is responsible for sampling the image information served as analog signal that is sent to A/D converter subsequently, aiming to convert analog signal to digital signal. It is important that those digital signal is sent to PC through Cypress non-destructively because those data need to be analyzed by a software on PC to acquire the useful information. This implementation not only clearly scans the image of checks, but it is high precision, simple design, and easy to carry.

A 640 X 400 pixels and 64 dots/mm2 2-dimensional (2-D) contact image sensor has been fabricated by integrating amorphous silicon (a-Si:H) photodiodes (PDs) and thin film transistors (TFTs). The sensor consists of 400 gate and 640 signal lines, and thus contains 256,000 pixels. The PD has a Cr/n-i-p a-Si:H/ITO structure. The TFT has an inverted staggered structure and Ta/TaMo is used for a gate electrode in order to suppress a gate pulse delay. When the TFTs of the n-th row are turned on, photo-generated charges stored in the PD capacitances in the n-th row are transferred to their respective signal line capacitances. After that, the charges are detected by an external voltage sensitive amplifier. The 640 parallel outputs are converted to the serial analog signal by a multiplexer for image processing. The sensor has achieved photoresponsivity of 7.2 V/lx-s, photoresponsivity non-uniformity of +/- 8% and the signal-to-noise (S/N) ratio of 50 dB at the operation of 30 ms/frame scanning speed. Crosstalk as the influence of adjacent lines both X and Y direction is less than 1.3%. This value is estimated to enable achievement of more than 64 levels of gray. The reproduced image quality regarding resolution was good for 8-point kanji characters. This technology will be applicable for multifunctional input/output device mounted on a system such as a pen computer and X-ray detector coupled to a scintillator.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Charge Coupled Device (CCD) has been widely used in full page scanner applications for many years. Since the length of a CCD is about one inch, a concave reduction lens is required to focus the image of a standard A4 size page of 8.5 inches width on the CCD. This results in a bulky assembly. Moreover, the whole assembly needs to be moved by a high power stepping motor, which suffers from a non-smooth movement causing distortion in the image. A contact type image sensor (CIS) module is designed to solve the aforementioned problem. The dimensions of an A4 size CIS module is only 18 X 18 X 224 mm. The module has all the elements required to capture an image. These are: (1) a hybrid image sensor board (which consists of a linear silicon butted image sensor array, an operational amplifier, and passive components); (2) an LED light source; (3) a one to one selfocTM lens; (4) a cover glass and (5) an aluminum case to house all of the above components. The hybrid image sensor board is fabricated by butting many silicon image sensor chips end-to-end on top of a ceramic substrate to achieve the desired length. Since the image sensor chip is silicon, the module can be operated at high clock rates with low noise characteristics. A resolution of 200 and 400 dots per inch (dpi) are designed and developed for facsimile and scanner applications. The CIS device description, operation and performance will be presented in this paper.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We have developed a technology for 2D matrix-addressed image sensors using amorphous silicon photodiodes and thin film transistors. We have built a small prototype, having 192×192 pixels with a 20μm pixel pitch, and assessed its performance. The nip photodiodes can have dark current densities of less than 1011 A.cm-2 (up to 5V reverse bias) and peak quantum efficiencies of 88% (at 580nm). We operated the sensor in real time mode at high speed (50 Hz frame rate and 64μS line time). The image sensor has a low noise performance giving a dynamic range in excess of 104. The maximum crosstalk is about 2%, which allows at least 50 grey levels. The bottom contact of the photodiode acts as a light shield from light through the substrate, which enables the sensor to be operated as an intimate contact image sensor to image a document placed directly on top of the array. In this mode, the CTF was 75% at 2 lp.mm1. Good quality images are demonstrated in both front projection and intimate contact imaging modes.

Recent development ofG4 fax and scanner requires a high speed, high resolution, and high contrast second generation image sensor. This paper describes a silicon butting Contact Image Sensor (CIS) module which has been developed and produced to solve the problems encountered by using CCD image sensors. Due to the flexibility ofthe design, the CIS module can be made for the A6, A4 ,B4 or other paper sizes. This device can be operated at high speed (2 MHz or higher), high dynamic range (1000: 1) and high resolution (400DPI). By adding alayer ofcolor filter on top of the photosensor, it is also applicable for the color G4 facsimile and color scanner.

FABRICATION AND PERFORMANCE OF A ONE-TO-ONE ERECT IMAGINGMICROLENS ARRAY FOR FAXR. H. Bellman, N. F. Borrelli, L. G. Mann and J. M. QuintalCorning Incorporated, Corning N.Y. 14831ABSTRACTNicrolens arrays which image a full size document onto aphotoreceptor for copying or transmitting purposes are currentlyof much interest. In particular those arrays which have totalconjugate distances less than 10mm are important because of thecompactness they afford in the contact image sensor (CIS) unitdesign.In this paper the fabrication of such atone_to_one arrayutilizing the photosensitive glass based SMILEmprocess isdescribed. The performance of the array in terms of contrast vs.spatial frequency for a facsimile document reader application istested in a commercial CIS unit. The overall measured performanceis examined in terms of the process parameters involved in thelens fabrication. Advantages and disadvantages of the microlensarray relative to other methods are considered.

An A4 page width and 300 dot/inch hydrogenated amorphous silicon thin film transistor (a- Si:H TFT) driven contact image sensor which can read more than 128 gray levels has been developed. Crosstalk due to the coupling between data lines in the multiplex circuit has prevented high gray scale reading. In order to eliminate crosstalk, a sensor with a new multiplex structure has been developed with a ground mesh shield layer inserted at the crossover points between each data line. The ground mesh shield pattern was designed to optimize the gray scale reproduction ratio R. With this sensor, R is more than 0.992 for a single bit, thus achieving 128 levels of gray. This design was compared to the performance of two other sensors, one without a ground mesh shield, the other using a data line meander pattern. This technology is also applicable to higher performance image sensors with greater than 400 dot/inch resolution.

The experimental results for different structures of contact image sensor are reported in this paper, which includes Schottky barrier, p-i junction, p-l-n junction, and MIS structures. The J-V characteristics of p-i-n a-Si: H contact image sensor under dark and illuminated conditions have been simulated by solving the Poisson's equation and the continuity equations, and the results are correlated with the experiments. The dependence of the dark and photo currents on the parameters such as the density of states in the gap, intrinsic layer width, dopant concentrations of p* layer and n+ layer are discussed.

Various sandwich structures of photodiode arrays using hydrogenated amorphous silicon films fabricated under similar process conditions were compared. As a result of this comparison, the p-i junction amorphous silicon stripe-type photodiode array was studied. This photodiode array has the same excellent sensor performance characteristics for contact image sensors as the p-i-n junction type, and it has a similar process. A contact image sensor using this photodiode array with eight elements/mm resolution and A4 size is discussed. This compact, high performance sensors was applied to GIII facsimiles. >

プリント配線板の高密度実装化に伴い, プリント配線板のパターンは微細化の一途をたどっている。それに伴い, 両面の導通穴も0.4φmm以下 (0.2～0.4mm) の小径穴あけ加工になりつつある。そのため, 穴あけ加工時のドリル欠損, 切り粉残りによる穴落ち, 穴ズマリ不良が従来の部品穴に比較し, 急増している。しかし損失を確保する上では, このような不良を改善することと同時に, 検出する必要があるが, このようなプリント配線板にあけられた小径穴は, もはや人間による目視では検査不可能な状況である。今回開発の自動穴ミス検査機は, 従来の縮小方式 (CCD使用) では, 検査に限界があった小径穴を, 密着型イメージセンサを応用し, 自動検査対応を可能にした。