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Common experience indicates the quality of a printed image depends on the choice of the paper used in the printing process. In the current report, we have used a recently developed device called a micro-goniophotometer to examine toner on a variety of substrates fused to varying degrees. The results indicate that the relationship between the printed color gamut and the topography of the substrate paper is a simple one for a color electrophotographic process. If the toner is fused completely to an equilibrium state with the substrate paper, then the toner conforms to the overall topographic features of the substrate. For rougher papers, the steeper topographic features are smoothed out by the toner. The maximum achievable color gamut is limited by the topographic smoothness of the resulting fused surface. Of course, achieving a fully fused surface at a competitive printing rate with a minimum of power consumption is not always feasible. However, the only significant factor found to limit the maximum state of fusing and the ultimate achievable color gamut is the smoothness of the paper.

In this paper, the possibility of EAPap as a piezoelectric sensor was investigated by the vibration control of the cantilevered beam. The EAPap sample was attached at the root of the cantilevered beam and used as a vibration sensor. The piezoceramic patch was also attached at the root of the beam and played as an actuator. The voltage output of EAPap showed same trend of that measured by the piezoceramic patch. The frequency bandwidth and quality factor of EAPap were similar to those of piezoceramic patch, which results EAPap has similar sensing capability of piezoceramic patch. To find the application of EAPap sensor, beam vibration control was performed. EAPap sensor output was considered as a position error of the cantilevered beam system and a simple PID controller was designed to suppress the vibration of the beam. The EAPap sensor output provided clear time response of the beam. The controlled system showed good vibration control performance of the beam. The results provided that EAPap has great potential as a piezoelectric vibration sensor.

This paper introduces a novel optical method to measure liquid penetration into porous, highly scattering media. Testing was conducted by measuring the sorption of glycerol into a paper sample consisting of cellulose fibre tissue with a grammage of 115 g m -2 . During wetting, optical coherence tomography (OCT) was used to detect dynamical changes in the sample's scattering properties. Distinguishing the border between the dry and the wetted area on the basis of separate A-scans was a challenging task. However, wetting behaviour could be investigated in the depth direction simply by constructing a composite image of the separate scans. In addition, the method also allowed the imaging of swelling behaviour in paper.

The propagation of broadband ultrasonic pulses in combined media that consist of printing paper of different porosity saturated with different liquids is studied. The experiments are performed with three types of paper, namely, Zoom Ultra (Stora Enso, Finland) with surface densities of 80 and 100 g/m2 and Data Copy (Mo Do, Sweden) with a surface density of 160 g/cm2, and with two types of saturating liquids: ethanol and transformer oil. To excite ultrasonic pulses and to detect them with a high time resolution, the laser optoacoustic spectroscopy method is used. For each type of liquid-saturated paper, the phase velocity of ultrasound is measured in the frequency range of 5–35 MHz. The absence of any noticeable frequency dispersion of the phase velocity is revealed. The possibility of measuring the porosity of printing paper on the basis of the theoretical model of a two-phase medium with the use of the corresponding experimental data is demonstrated.

This study is focused on laser structuring processes for producing secure tactile features on paper-based security documents. The feasibility of using the developed technique allows users and/or machines to discriminate among genuine and counterfeited security documents and/or facilitate the tactile detection by visually impaired people.

In this paper a new method is proposed to control a vision-based robot in large navigation spaces. In this case, visual features observed by an on-board camera can change drastically or even disappear completely between the initial image, as seen at the beginning of a task, and the final image, as seen at the desired position of the robot. These features are therefore not suffcient for controlling the entire motion of the robotic system from beginning to end. This problem requires a more complete definition and representation of the navigation space. This can be achieved by a topological representation, where the environment is directly defined in the sensor space by a data-base of images. In our approach, this data-base is acquired during an offline learning step. An image retrieval method then indexes and matches a request image, given by the camera, to the closest view within the data-base. In this way, an image path is extracted from the database to link the initial and desired images providing enough information to control the robot. The central point of this paper is focused on the closed-loop control law that drives the robot to its desired position using this image path. The method proposed does not require either a global reconstruction or a temporal planning step. Furthermore, the robot is not obliged to converge directly upon each image waypoint but chooses automatically a better trajectory. The visual servoing control law designed uses specific features which ensure that the robot navigates within the visibility path. Experimental simulations are given to show the effectiveness of this method for controlling the motion of a camera in three-dimensional environments (free-flying camera, or camera moving on a plane).

The size distribution and total amount of the particles in paper pulp is vital information for the paper manufacturer in optimising process control and maintaining a high product quality. There is a further need for improving the on-line measurement methods to measure these parameters. It is known that fibre and fines fractions in the pulp have different optical and acoustic properties. In this study, we simultaneously use laser radar and laser generation of acoustic waves to further study optical and acoustic parameters, such as optical time delay, acoustic speed and attenuation. A near infrared pulse laser is used to illuminate the pulp suspensions and the time-of-flight of scattering photons is recorded; and at the same time, a high energy pulsed laser is applied to produce an acoustic wave. The acoustic wave propagates through the pulp suspensions and an acoustic transducer is used to detect the signals from which the attenuation and acoustic speed are determined. The results show that these combined optical techniques can potentially determine the content of fibres and fine particles simultaneously.

In 1905 Karl Schwarzschild published three papers on optics, two of which revolutionized the field of reflecting telescope optics. In his first paper he developed a full theory of the aberrations of reflecting telescopes, generalizing the Eikonal of Bruns to take into account systems with an infinite long conjugate. In the second paper Schwarzschild applied his formulation to a masterful analysis of 2 mirror anastigmatic systems, along the way discovering the so called Ritchey-Chretien aplanat, 18 years Ritchey and Chretien's announcement. Numerous other innovations are given in what must be seen as being among the most important papers on the aberrations of optical systems ever written.

This paper presents the design and development of a safe MEMS based micro electro-thermal igniter for a safe microfuze for military purpose. The proposed device"s architecture is made of: (1) one pyrotechnical micro igniter, (2) one arming function, (3) one disarming function and (3) one sterilization function. The pyrotechnical electro-thermal igniter consists in a resistive element that converts electrical energy into heat to initiate an energetic material. The arming function permits the igniter to be armed, ready to fire, only if the ignition conditions are respected. For that, a short-circuit to the electrical ground is cut and the igniter is connected to the power supply. The igniter can be reset to the safe mode (disarmed state) thanks to the disarming function that reconnects the igniter's electrical pads to the electrical ground. If necessary the igniter can be sterilized meaning that the system's ignition capability is definitively removed. All these functions are based on the use of two electro-thermal micro switches : one ON-OFF and one OFF-ON. Due to the application requirements (the fuze is used once but after a long storage, all components must have a high level of safety and reliability and the power consumption must be minimized), we opted for a new generation of one shot, safe and reliable micro switches. They are based on electro thermal mechanisms and consist in breaking one electrical connection (ON-OFF switch) or micro soldering locally two electrical connections (OFF-ON switch). Both switches have been developed in MEMS technology, characterized and are presented in this paper. A prototype of safe micro igniter with ON-OFF and OFF-ON switches has been also realized and is presented.© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents the whole process of building up a high precision, high dynamical MEMS acceleration sensor. The first samples have achieved a resolution of better than 500 ug and a bandwidth of more than 200 Hz. The sensor fabrication technology is shortly covered in the paper. A theoretical model is built from the physical principles of the complete sensor system, consisting of the MEMS sensor, the charge amplifier and the PWM driver for the sensor element. The mathematical modeling also covers problems during startup. A reduced order model of the entire system is used to design a robust control with the Mixed-Sensitivity H-infinity Approach. Since the system has an unstable pole, imposed by the electrostatic field and time delay, caused by A/D-D/A conversation delay and DSP computing time, limitations for the control design are given. The theoretical model might be inaccurate or lacks of completeness, because the parameters for the theoretical model building vary from sample to sample or might be not known. A new identification scheme for open or closed-loop operation is deployed to obtain directly from the samples the parameters of the mechanical system and the voltage dependent gains. The focus of this paper is the complete system development and identification process including practical tests in a DSP TI-TMS320C3000 environment.

In this paper a model for auditory perception is introduced. This model is based on a network of integrate-and-fire and resonate-and-fire neurons and is aimed to control the phonotaxis behavior of a roving robot. The starting point is the model of phonotaxis in Gryllus Bimaculatus: the model consists of four integrate-and-fire neurons and is able of discriminating the calling song of male cricket and orienting the robot towards the sound source. This paper aims to extend the model to include an amplitude-frequency clustering. The proposed spiking network shows different behaviors associated with different characteristics of the input signals (amplitude and frequency). The behavior implemented on the robot is similar to the cricket behavior, where some frequencies are associated with the calling song of male crickets, while other ones indicate the presence of predators. Therefore, the whole model for auditory perception is devoted to control different responses (attractive or repulsive) depending on the input characteristics. The performance of the control system has been evaluated with several experiments carried out on a roving robot.

This paper reviews state of the art mask modeling for optical lithography. Rigorous electromagnetic field (EMF) simulation of light diffraction from optical masks is compared to the traditional assumption of an infinitely thin mask, the so called Kirchhoff approach. Rigorous EMF simulation will be employed to analyze mask polarization phenomena which become important in the ultrahigh NA regime. Several important lithographic phenomena, which can be explained only with rigorous EMF simulation, are discussed. This includes the printability of small assist features, intensity imbalancing for alternating PSM, and process window deformations. The paper concludes with a discussion on material issues and algorithmic extensions which will be necessary for an accurate modeling of future mask technology.

A non-contacting online caliper measurement has been papermakers' dream for over two decades. Currently, paper thickness is measured using buttons contacting the paper web on both sides. In such a configuration, paper thickness is assumed to be the distance between the contacting surfaces and determined by a magnetic measurement principle. However, this arrangement of contacting measurement has several disadvantages including sheet marking, hole creation, dirt build-up on the contacting buttons, wearing of the contacting surfaces, and even sheet breaks. Moreover, the current trends in paper manufacturing, especially the increasing use of recycled raw materials are necessitating the development of a more reliable thickness measurement solution that is not affected by dirt and other material on paper or board sheet surfaces. So far, a non-destructive, on-line thickness measurement has not been successfully applied in paper production environment. Recently, Metso Automation has successfully piloted in several mills a caliper sensor that does not contact the sheet on both sides and is able to measure paper thickness with sub-micron accuracy. The new sensor is based on single sided laser triangulation. This paper presents the measurement set-up and discusses the challenges encountered. Measurement results obtained in mill trials with various paper grades are reviewed and compared to those made simultaneously with contacting, on-line sensors and off-line laboratory results of the same sheet. Factors affecting the measurement with conventional and optical thickness sensors are also discussed.

Chemical and biochemical sensing is under the extensive research all over the world and many chemical and biochemical sensors are finding increasing number of applications in industry, environmental monitoring, medicine, biomedicine and chemical analysis. This is evidenced by each-year-growing number of international scientific conferences, in which advances in the field of the sensors are reported. One of the main reason why only a few sensors reach the international market, notwithstanding the high number of laboratory prototype described in many peer reviewed papers, lies in the fact that a biochemical sensor is a highly interdisciplinary "object" the realization of which requires the team work of scientists coming from different areas such as chemistry, physics, optoelectronics, engineering, biochemistry, and medicine. And this peculiarity is not easily found in the research teams. In the present paper, the fundamental bases of chemical and biochemical optical sensing are summarised and the new trends are described.

Photonics is far behind electronics in maturity. The devices are orders of magnitude larger than their electronics counterparts and the functionality is low. But it appears that these issues are not fundamentally impossible to solve. In this paper some of the emerging possibilities to overcome the limitations mentioned above are briefly treated, and we discuss the utilization of these comparatively new phenomena to widen the application envelope of photonics technology to generate functions not normally associated with photonics. These developments could lead to quantum leaps in photonics devices, to complement the forceful engineering improvements. Examples of such potential candidate research fields for quantum leaps are: Coherent light matter interaction, plasmonics, quantum information and communications, photonic crystals, intersubband based devices. The list is by no means exhaustive. This paper will concentrate on coherent light matter interaction, plasmonics and photonic crystals.

In this paper, we discuss some of the leading issues in through the wall radar imaging (TWRI) problems. We focus on the primary system challenges and deliverables, dealing only with the applications of statistical signal and array processing. Applications of antenna design and electromagnetic propagation are equally important, but they are both outside the scope of this paper. The material presented considers key desirable TWRI system properties and features and provides candidate solutions to achieve them. We focus on research performed at Villanova University and demonstrate some of our recent approaches to address system functionalities and requirements using analyses, computer simulations, and real-data. The paper does not attempt to cover all progress made in the field to date nor does it intend to compare the proposed techniques with alternative and competitive methods. It is written with the primary purpose of bringing to the reader many leading challenges and diverse issues worthy of considerations.

The Air Force Research Laboratory (AFRL) has embarked on a variety of research programs that embrace the insertion of new electro-optical and infrared technology as well as advanced operational concepts to significantly improve capabilities for the detection and discrimination of difficult targets. The AFRL vision employs a distributed, layered sensor system combining passive and active sensors to rapidly detect battlefield threats and support high confidence identification to take immediate action. This paper will provide an overview of this layered sensing vision as well as describe the technology development directions that AFRL is pursuing in support of this advanced concept. The paper will specifically focus on relevant passive infrared technology areas such as spatial, spectral, polarimetric, and temporal sensing (separate and combined). It will also discuss how this technology is envisioned to be applied to the range of operational platforms, from standoff surveillance from large aircraft to close-in sensing from small unmanned aerial vehicles.

This paper highlights recent advances toward flexible cholesteric displays including new night vision applications for military use and full color. Particular emphasis is paid to recently developed encapsulated cholesteric liquid crystals that are necessary for printing and coating the materials as well as prevent erasure of the image during flexing or handling the display. The paper presents recent results from encapsulation of cholesteric materials using polymerization induced phase separation and their progression towards thin flexible plastic based cholesteric displays. Several other key issues in the transition from smooth rigid glass substrates to flexible plastic substrates including spacing control and preparation of surfaces are discussed. Lastly, the night vision mode and night vision applications of cholesteric displays are also presented.

Displays for military vehicles have very distinct operational and cost requirements that differ from other military applications. These requirements demand that display suppliers to Army and Marine ground-environments provide low cost equipment that is capable of operation across environmental extremes. Inevitably, COTS components form the foundation of these “affordable” display solutions. This paper will outline the major display requirements and review the options that satisfy conflicting and difficult operational demands, using newly developed equipment as an example. Recently, a new supplier was selected for the Drivers Vision Enhancer (DVE) equipment, including the Display Control Module (DCM). The paper will outline the DVE and describe development of a new DCM solution. The DVE programme, with several thousand units presently in service and operational in conflicts such as “Operation Iraqi Freedom”, represents a critical balance between cost and performance. We shall describe design considerations that include selection of COTS sources, the need to minimise display modification; video interfaces, power interfaces, operator interfaces and new provisions to optimise displayed video content.

In this paper, the performances and limitations related to the high frequency noise properties of SOI MOSFET Technology are investigated. The study is conducted through powerful analytical noise parameters calculation, experimental data, and physical based drift-diffusion noise modeling. In addition to the noise generated by the inner part of the active device, the influence of access resistances, overlap/fringing capacitances, tunneling gate current are discussed qualitatively and quantitatively. The paper ends up with a critical discussion related to the "New Era SOI Technology" to come and its influence on the noise performance.

Progress in optics led to the point when scientists and engineers operate the pulses of the electromagnetic energy containing only a few (in fact, sometime less than one, see examples in [1]) oscillations of the field instead of monochrome or quasimonochrome waves. Even omitting physical problems of interaction between field and matter, including those associated with essential nonlinearity due to extremely high amplitudes of the field, one encounters a lot of problems caused by extraordinary large homogeneous spectral bandwidth of ultrashort pulses. Linear optics of ultrashort pulses essentially differs from that of monochrome waves; hence, the development of appropriate methods for description of such pulses propagation through an optical system is necessary. It is common to our perception to deal with monochrome wave transformation, not wide-spectrum signal one, because in the traditional optics there is the set of solutions for the typical problems. The purpose of this presentation is to show that the equivalent set may be developed also for the optics of ultrashort pulses. As a result, the qualitative study of the diffraction and interference ofultrashort pulses becomes as simple as the ray optics. There are different methods of the analysis of diffraction and interference phenomena. The first possible approach is based on Huygens representation of the diffraction phenomena. Traditional procedure involves Fourier transform of the initial pulse process to get a set of monochrome waves. Then one analyzes the diffraction of each of those waves and finally the resulting monochrome diffraction fields sum back to form a scattered pulse. Rather widely used [2, 3, 4], this method implies reconsideration of developed solutions of classical diffraction problems to take into account some second-order components. Thrown away in the conventional theory as contributing only small phase correction for rather law frequencies, they become significant for high frequency components of the field. Another method suggests decomposition of the initial pulse into a set of wavelets [5]. Being convenient to those researchers who operate with an equal ease with this class of functions and with monochrome waves, this method does not possess the clearness of first one. Moreover, some of them does not meet the causality principle. At the same time, there is another group of methods based on one of principal results of general theory of diffraction [6]. Their formulation is closer to Young interpretation of diffraction and considers the interaction of waves scattered by the edge of aperture and through-passing one [7]. In acoustics and electro-engineering, the method based on the formalism of Green function for the wave equation [8, 9] is used. The fact that this method performs well for linear system analysis in electronics supported us in our attempt. In optics, it was successfully used by J. Connes [10] and L. Mertz [1 1], for example. Both of them studied the propagation of pulses through some most simple devices. Moreover, their analysis was based only on intuitive concepts that led to some mistakes, as it becomes clear today. Nevertheless, the general conclusion on the possibility of using the Dirac transform for the description of the waveform conversion in the process of propagation through the linear optical system became obvious. The technique based on 8-wave ideas proposed in our previous publications [12, 13, 14]. Those papers demonstrated the simplicity of interpretation of spatial and temporal form of the diffracted wave transformation using the pulse approach. The present paper extends this concept and demonstrates complete agreement of its results with classical theory for monochrome waves; the method opens a way to the development of specific software for the analysis of propagation of ultrashort pulses. All methods mentioned above give identical results. To our knowledge, the S -wave approach was not used directly for the solution of diffraction problems in the Kirchhoff approximation. However, it seems to be handy for the description of short pulses propagation. Moreover, it was shown in [12, 14] that the method can clarify some features of diffracted wave that can give a key to a fine experiment realization

In this paper, we show that the communication channel known as writing in memory with defective cells is a relevant information-theoretical model for a specific case of passive warden steganography when the sender embeds a secret message into a subset C of the cover object X without sharing C with the recipient. The set C, which is also called the selection channel, could be arbitrary, determined by the sender from the cover object using a deterministic, pseudo-random, or a truly random process. We call this steganography "writing on wet paper" and realize it using a simple variable-rate random linear code that gives the sender a convenient flexibility and control over the embedding process and is thus suitable for practical implementation. The importance of the wet paper scenario for covert communication is discussed within the context of adaptive steganography and perturbed quantization steganography. Heuristic arguments supported by tests using blind steganalysis indicate that the wet paper steganography provides improved steganographic security and is less vulnerable to steganalytic attacks compared with existing methods with shared selection channels.

An automatic recognition system for Paper Currency Numbers was developed in this paper. The paper currency number can be recognized and recorded by this system at the same time of binding. At First, an image of 8 bits grey-scale was acquired by CCD camera, and then some output number clusters can be through process of segmentation by Grey Ridge-Valley algorithm, orientation by projection, and character recognition by structure-analyzing algorithm. Results of experiments demonstrated that the proposed algorithm of gray ridges and valleys can extract feature effectively, the algorithm of distance of traversing number body orientation acute, and this system achieves a high recognition rate and a fast recognition speed. It still reached the practical degree. The system has applied national patent.

High-resolving full-field OCT method is considered that provides increased resolution and interferometric data acquisition speed due to high optical magnification and electronic lateral scan provided by video camera. OCT data processing algorithm based on signal squaring with subsequent low-pass filtering is considered. Experimental results obtained when evaluating samples of paper material are presented and discussed.

We design the emission and detection optical paths of three monochromatic infrared light sources with different wavelength. The three light sources are placed according to the different angles, so that the three kinds of monochromatic lights are converged on the same point of the sample. Using the method, we can detect the same point and improve the measurement accuracy. We choose the standard near-infrared monochromatic light source, so that we can save some equipments, such as tungsten- halogen lamp, filtered wheel, collimation focalizer, electric machine, and so on. In particular, we save the cumbersome cooling system, reduce the volume of the instrument greatly and reduce the cost. The three monochromatic light sources are supplied by the same pulse power source, to ensure their synchronous working.

In-plane piezoelectric charge constant of Electro-Active paper (EAPap) was investigated based on direct and converse piezoelectric effects. EAPap samples were made with cellulose film with very thin gold electrode coated on both sides of the film. To characterize direct piezoelectricity of EAPap, induced charge was measured when mechanical stress was applied to EAPap. In-plane piezoelectric charge constant was extracted from the relation between induced charge and applied in-plane normal stress. To investigate converse piezoelectricity, induced in-plane strain was measured when electric field was applied to EAPap. Piezoelectric charge constant was also extracted from the relation of induced inplane strain and applied electric field. Piezoelectric charge constants obtained from direct and converse piezoelectricity are 31 pC/N and 178 x 10-12m/V for 45 degree sample, respectively. Measured piezoelectric charge constants of EAPap provide promising potential as a piezoelectric material.

This paper reviews the basic concepts of laser propulsion and summarizes work done to date using a 10 kW device. The paper describes a candidate megawatt class CO 2 laser system which can be scal ed relatively near-term to multi-megawatt power levels using demonstrated technology. Such a system would potentially be capable of launching micro-satellites into low earth orbits (LEO) at relatively low cost. Our projections indicate that payloads of about 1kg/megawatt are achievable. The long wavelength of a CO 2 laser will require the use of a large aperture telescope and/or large effective beam capture area for the lift vehicle. We be lieve that these limitations, not withstanding, rep-pulsed CO 2 in a blow-down configuration lasting 200-300 seco nds could achieve the desired propulsion objectives. The laser would use a helium-free, nitrogen/carbon dioxide mixture to provide a very cost effective fuel. Keywords: Laser propulsion, pulsed CO 2 lasers, micro-satellite launching. 1. INTRODUCTIONThis paper discusses conceptual approaches for the design of repetitively pulsed CO

We developed a 25GB ROM disc whose substrate is made of paper. Structure of the disc is based on the Blu-ray Disc format. We improved mechanical characteristics of a paper core by introducing a symmetrical multi-layer structure. The signals in the paper disc were reproduced successfully and the jitter values were less than 6%.

Electro-Active Paper (EAPap) is attractive for EAP actuator due to its merits in terms of lightweight, dry condition, large displacement output, low actuation voltage and low power consumption. A promising EAPap actuator has been developed using cellulose paper. It is necessary to investigate the environmental factors for many applications. The performance variation along with the temperature and humidity is investigated. Tip displacement is measured by laser sensor and the power consumption of EAPap is investigated. When 0.3kV/mm of excitation voltage is applied, more than 4mm of tip displacement is obtained out of 40mm long EAPap sample. Since the power requirement of EAPap is so small(8.8mW/cm 2 ), it can be activated by remote microwave power, which is promising for many applications

The construction of electromechanical actuator has been achieved by using the conducting polypyrrole films deposition onto a gold-coated cellophane paper. This is probably the first report of this type of paper actuator. The conducting polypyrrole was electro-generated using either galvanostatic or potentiostatic conditions at 0.5 mA/cm2 current density or 0.7 volts applied potential. The two types of actuators were constructed namely: 1.Ppy/Cellophane bilayer 2. Ppy/ Cellophane paper /Ppy trilayer using electrochemical technique. These actuators showed a reversible and reproducible displacement in acetonitrile solution containing LiClO4 (1M). The maximum displacement of 9.1 mm was recorded for tri-layer device and 3.5 mm for bi-layer device in 1M LiClO4 acetonitrile solutions. The prepared actuator devices were investigated for their mechanical actuation in air medium. The actuation in air is comparatively less than in solution actuation, but still it showed significant movement in air also. The results obtained in acetonitrile solution containing 1M LiClO4 shows that the actuator requires very low excitation voltages of 0.2 MV m-1 at 0.5 Hz frequencies. The effect of humidity on the actuation properties was addressed. The humidity measurement was carried out between 60% to 95% humidity with the help of humidity-temperature controlled chamber. The resonating frequency of 3 Hz at 6 volts had shown 1.8 mm displacement at 95% humidity for gold-coated cellophane sample without polypyrrole.

In this study, we propose to apply the method optical coherence tomography (OCT) for paper characterization. A PC-controlled experimental measurement system for OCT-imaging of paper is described in detail. A superluminescent diode is used as a light source in a Michelson interferometer. A rapid scanning optical delay line is using a piezo-transducer to modulate the measurement signal for optical heterodyne detection. Amplification, filtering and demodulation are performed by the unit specially designed for this purpose. Experimental measurements include the OCT slice imaging of a paper sample and comparison with a SEM-image. Also some results in surface profilometry are presented briefly. Discussion part gives some ideas of further research that will be carried out in the future.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The printability of newsprint and liner is addressed through the analysis of CLSM images. The surface topography and porous structure of the paper are physical properties heavily correlated with the paper's formation, and, hence, important factors affecting the printability of the paper. The surface 3D structure of the paper is measured by using topographic CLSM images from which the pore size distribution can be estimated using image analysis. The experimental results have both been compared to a theoretical model of the cross-sectional area of void volumes in paper and also with paper physics measurements, specially related to the offset print-through problem. Good correlations have been found, and results so far are promising, but still there is a need for improved analysis of the 3D structure of paper, both on the measurement and modeling side.

The goal of this work is to study the relationship between the colorimetric characteristics that identify a kind of paper and those that allow us to evaluate its color reproduction capabilities on inkjet printers. A set of 29 different commercial papers from several companies has been tested. The category of those papers ranged from photo quality to prepress proof and ordinary office papers, being their finishing matte, semi-matte or glossy. For each sample, we have measured their reflectance, intrinsic reflectance, opacity, CIE whiteness index and tint. All these measurements followed the procedures established in the international standards about paper and board. Then, we have printed on three different sheet of each paper the color chart proposed in the international standard for color printer characterization ANSI IT8/7.3. When calculated the CIELAB coordinates using the D50 standard illuminant, we studied the dynamic range, color gamut and the rendering linearity. The results show that the colorimetric properties and reproduction capabilities of the 29 commercial papers let us cluster them in accordance with their behavior. However, we found no systematic correlation between color reproduction and specific colorimetric properties of the types of paper: we should search for other physical (not just colorimetric) properties (for instance, gloss or ink absorption capacity).

It is said that clinicians today learn less and less about more and more until they end up knowing nothing abouteverything, whereas researchers learn more and more about less and less until they end up knowing everything aboutnothing. This is a phenomenon which is slowly creeping into the field of clinical applications and basic research in lasersurgery and laser therapy. This trend is definitely to be discouraged, as it will effectively narrow the scope of bothclinicians and researchers at a time when the scope needs to be expanded just as appropriate applications in lasersurgery, and bona fide applications for laser therapy are also expanding. "Publish, or be damned" is a well-knowndictum in the heady halls of academe. Unfortunately, for many of the papers which are submitted on laser applicationsbut which do not reach the pages of the target journal, and indeed for some papers which are published elsewhere byjournals which should know a little better, or should at least have done their homework, the saying should perhaps beamended to; "Publish and be damned," meaning that the papers actually do more harm than good to the cause of lasersin medical science.Key words: How to write a scientific paper, ideal scientific research, article lay-out, material and methods, type oflaser, dosageCorrespondence address

The effect of a Q-switched Nd:YAG laser irradiation applied for ablative cleaning of the surface contaminants on cellulose samples and aimed on conservation of historical paper documents is investigated. The removal effectiveness of an artificial graphite contamination from model samples is investigated in dependence on the laser wavelength (532, 355 and 266 nm) and fluence (0.3 to 0.9J/cm 2 ) and also the surface color changes are measured. Damages of cellulose fibers due to laser interaction are examined by means of the SEM technique. For irradiation at 266 nm only partial removal of the contamination and a distinct cellulose degradation, and also the yellowing of paper surface are observed. For the 355 nm wavelength and energy fluence below 0.6 J/cm 2 the degradation of cellulose fibers does not occur. However, a slight yellowness of the surface is observed. The optimal cleaning wavelength of 532 nm and safe energy fluence below 0.6 J/cm 2 found experimentally agree with literature.

Results of paper cleaning by means of the 532 nm Nd:YAG laser (pulse length 6 ns, fluency 0.3-0.6 J/cm2) are reported and discussed. Results of the surface cleaning of the paper samples originating among others from the two oldest Polish Bibles (XVI c.) are examined by the SEM technique after laser processing. For the process diagnostic the LIF spectra of paper samples recorded under excitation at 266 nm and 532 nm before and after processing are analysed and spectra of the non-contaminated samples are taken for reference. The presence of contamination and also cleaning history is evidenced in the recorded spectra. Comparison of SEM images and also the spectral characteristics of the originally contaminated samples before and after laser treatment confirm results of the laser cleaning.

Silver physical development, a now-abandoned technique used for developing photographic film or paper, is one of the most powerful methods for visualizing latent prints on paper. The method develops the water-insoluble components in the print residue. These components include the fats and oils or lipids found on the skin of fingers. The resulting developed print, referred to as a silver physically developed (Ag-PD) print, is made up of (gray to black) silver particles adhered to the fingerprint residue. Such prints are usually intensified (made darker) with a hypochlorite treatment. This process converts silver to silver oxide making the Ag-PD print become a Ag 2 O-PD prints. Often such (Ag-PD or Ag 2 O-PD) prints are found on areas with heavy or patterned printing making them difficult to see. This work resolves this problem by chemically lightening the print and darkening (suppressing) the interfering background.

Paper landscape refers to both an iterative design process and a document as an aid to the design and development process for creating new information visualizations. A paper landscape engages all stakeholders early in the process of creating new visualizations and is used to solicit input; clarify ideas, features, requirements, tasks; and obtain support for the proposal, whether group consensus, market validation or project funding.

A device has been designed for off-line optical paper inspection and quality control of stripes and holes in the cigarette paper. Hardware description is first presented including main paper characteristics to be measured. Typical paper stripe and holes structures are then discussed with image processing and analysis considerations to discriminate these structures, focusing in the problems derived from the small area of holes and of their internal structure that is analyzed with a confocal microscope. Algorithms for image processing and analysis are described. These algorithms involve equalization, binarization, stripes structure detection, holes distribution and statistics.

In this paper the use of laser speckle correlation as a mean to measure the micro-structural changes in paper exposed to a changing environment will be presented. Of particular interest will be changes in humidity and crack propagation. Speckle correlation is a technique that calculates the local structural change in a speckle pattern as the object deforms in real time. The response of the technique is the local rate of micro-structural change in the material. Speckle correlation is hence a complement to other speckle metrology techniques. The paper starts with a short introduction to speckle correlation but will focus on applications of the technique on paper. Results from studies of wetting of printing paper at the flock scale, dynamic response in copy paper when exposed to a sudden change in humidity and crack propagation in a notched sheet of Kraftliner are included.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This study deals with the measurement of the deformation of sheets of recycled paper subjected to tensile loads using an electronic speckle pattern interferometry (ESPI) technique. Specimens with fibers, which constitute a sheet of paper, parallel and perpendicular to the direction of paper making are used to investigate the effect of the arrangement of fibers on the tensile property. The deformation of recycled paper is compared with that of virgin pulp paper. Results reveal that a large two-dimensional deformation of recycled paper can be measured using the ESPI technique, and that the directions of fibers, which constitute a sheet of paper, have a significant effect on the two-dimensional deformation of recycled paper.

A non-supervised clustering based method for classifying paper according to its quality is presented. The method is simple to train, requiring minimal human involvement. The approach is based on Self-Organizing Maps and texture features that discriminate the texture of effectively. Multidimensional texture feature vectors are first extracted from paper images. The dimensionality of the data is then reduced by a Self-Organizing Map (SOM). In dimensionality reduction, the feature data are projected to a two-dimensional space and clustered according to their similarity. The clusters represent different paper qualities and can be labeled according to the quality information of the training samples. After that, it is easy to find the quality class of the inspected paper by checking where a sample is placed in the low-dimensional space. Tests based on images taken in a laboratory environment from four different paper quality classes provided very promising results. Local Binary Pattern (LBP) texture features combined with a SOM-based approach classified the test data almost perfectly: the error percentage was only 0.2% with the multiresolution version of LBP and 1.6% with the regular LBP. The improvement to the previously used texture features in paper inspection is huge: the classification error is reduced over 40 times. In addition to the excellent classification accuracy, the method also offers a self-intuitive user interface and a synthetic view to the inspected data.

In this paper we give an overview on NTera's novel reflective display technology with real 'ink-on-paper' readability. Our technology is based on mesoporous wide-bandgap semiconductor films modified with self-assembled monolayers of electrochromic chromophores. The direct vicinity of each electrochromophore to the semiconductor allows its electronic addressing in the millisecond domain. The high molar extinction coefficient of the organic chromophores in conjunction with the extremely large specific surface area of the mesoporous semiconductor substrate allows to achieve deep colorations with high contrast ratios. Combined with a unique white reflector technology yielding reflectivities above 50 percent and excellent angular contrast independnece, oru displays show outstanding optical properties, comparable to those of ink on paper. Applying simple printing techniques these displays can be manufactured from commercially available nanomaterials like TiO 2 or other doped or undoped metal oxides. Along with favorable electronic properties like low power consumption and excellent open-circuit memory electrochromic displays seriously rival conventional LCD display applications.

In this paper, the problem of combined vision/force servo control for robot manipulator is addressed. Three different robot vision control strategies: position-based, image-based, and hybrid control are combined with an impedance-based force controller and a comparison of these three combined vision/force control methods is investigated for the first time, in the context of generic robot kinematic-based sensory-task-space control structure. Furthermore, the issue of contact surface parameters estimation is also investigated. Simulation results have demonstrated that all the above vision/force control strategies are comparable in terms of both the dynamic response and accuracy of positioning and force control.

This paper introduces tracking control system with visual feedback to a moving object by using the measurement device which we developed. In order to recognize the moving object, we use two method, using cross-shape mark and Orientation Code Matching (OCM). And the measurement device is constructed PID control system with Extended Kalman Filter in order to track to object. Through the several experiments, we verify the percormance of recognition and tracking.

This paper gives a comprehensive and up-to-date review of our research activity on MEMS (micro electro mechanical systems) for all- optical fiber optic communications. Micromechanical approach for handling optical signal has advantages over solid-state devices in terms of high contrast intensity modulation by relatively large change of refractive index, large spatial scan angle by optomechanical reflection or refraction, and optical transparency in wide range of wavelength. MEMS also has industrial impact in a sense that it could potentially eliminate or cut down the cost of optical assembly thanks to the optical pre-aligning or self-aligning capability. In particular, we take an example of MEMS variable optical attenuator (VOA) that we have commercially released in cooperation with an industrial partner. Besides fiber optic MEMS, we also mention other applications such as projection displays using a high-speed MEMS optical scanner for scanning modulated laser beam to create images. Furthermore, we also introduce a MEMS color pixel based upon the mechanically tunable Fabry-Perot interferometer made of two plastic films; the color pixel can be assembled in an array format to create a transparent-type over-sized electronic poster which is mechanically flexible and electrically rewritable.

The ongoing Chinese ever-ambitious project of Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) has brought about a tremendous challenge for the control engineers. To the bottom line the giant 4-meter class ground telescope is a comprehensive optomechatronic platform to achieve high performance and functionality, such as its capability of observing 4000 stars simultaneously, which will set a world record in contemporary ground survey telescopes. This paper outlines the R&D stages of the control system for the project along with its integrated strategy of optomechatronic components in general and network control framework in particular. The approach is to make a careful investigation with respect to the time crucialness for execution of different tasks so as to utilize different networks. However, the overall network framework is based on a distributed platform, hierarchical structure and open architecture to boost the flexibility. Vigorous study has been invested and a number of cutting edge techniques have been applied to meet the tough network control requirements, such as real-time database, powerful interfaces, sophisticated controllers, remote control, etc.

In this letter, we proposed a simple and cost-effective variable optical attenuator (VOA) through controlling a mechanical misalignment between 2 single mode fibers. A piezoelectric ceramic tube having 4 electrodes on the surface is the key component in our proposed structure. We can change the deflection of the tube by controlling the applied voltage on the electrodes of the tube, which causes the optical loss to be dependent on the applied voltage. The fact that the piezoelectric ceramic tube can be easily fabricated by using the electro-phoretic deposition processing makes our structure more attractive for mass production. The tube-fabrication processing is out of the range in this paper. So, the detail technical approach of the tube fabrication is excluded intentionally. The numerical analysis about the optical loss related to the various mechanical offsets is also investigated. From our experimental results, the dynamic range of the proposed structure is about from 0 to 25 dB when the applied voltage range is from 0 to 600 V DC. Our proposed structure can be a good candidate for a simple and cost-effective variable optical attenuator in optical communication system field.

In phase-shifting digital holographic interferometry for measuring a displacement distribution of an object, holograms and reconstructed images have speckle noise and they provide large error in the calculation of displacement analysis. In order to decrease the effect of speckle noise, we previously proposed a new method using windowed holograms. In this paper, we propose a new averaging method of the obtained phase-difference values. Many phase-difference values at a point obtained by different windows for a hologram are averaged by considering the weight for each phase value. The weight is changed as the m-th power of the absolute amplitude of the complex amplitude of the reconstructed object. As the result, when the number n of the windowed holograms becomes larger, the standard deviation of the error becomes smaller. When the power m is 2, the error becomes the minimum. The standard deviation of the errors in the case of a flat plate with 316 nano-meter out-of-plane displacement is 88 pico-meter when n=1024 and m=2.