Methods and compositions are provided for forming complexes between dsDNA and novel DNA-binding polymers comprising N-terminal thiophene-containing moieties which exhibit selectivity for T-A base pairs. By appropriate choice of target sequences and DNA-binding polymers, complexes comprising polymer-DNA are obtained with high association constants. The formation of complexes can be used for identification of specific dsDNA sequences, for inhibiting gene transcription, and as a therapeutic for inhibiting proliferation of undesired cells or modulation of expression of specific genes.

The information provided herein and references cited are provided solely to assist the understanding of the reader, and does not constitute an admission that any of the references or information are prior art to the present invention.
With the explosion of techniques for the synthesis, analysis and manipulation of nucleic acids, numerous new opportunities have arisen in diagnostics and therapeutics. In research there is substantial interest in being able to identify DNA sequences, which may be associated with specific organisms, alleles, mutations, and the like, to understand particular genetic processes, to identify diseases, for forensic medicine, etc. Also, for many purposes, one may wish to modulate the expression of a target gene, so as to identify the function of such gene, or the cellular changes brought about by changes in the expression of such gene. In therapeutics, one may wish to inhibit the proliferation of cells, such as bacterial, fungal and chlamydia cells, which may act as pathogens, of viruses, of mammalian cells, where proliferation results in adverse effects on the host, or other situations. In vivo, one may provide for reversible or irreversible knock out, so that information can be generated on fetal development, or the effect on the organism of reduced levels of one or more genetic products.
Polyamide oligomers of nitrogen-containing five-membered heterocycles can be used to bind predetermined sequences of double stranded DNA (dsDNA). DNA recognition by polyamide oligomers depends on specific acid pairings that are oriented in the amino to carboxyl direction with respect to the 5′-3′ direction of the DNA helix. Thus, polyamide oligomers bind dsDNA in an antiparallel fashion and in a stoichiometric ratio of 1:1 or 1:2, oligomer to DNA (Dervan et al., Current Opinion in Chemical Biology, Vol. 3: 688, 1999). Antiparallel pairs of certain five-membered heterocycles preferentially bind to specific base pairs on duplex DNA. These antiparallel pairs have proven useful for the recognition of hundreds of predetermined DNA sequences by polyamide oligomers. Listed below in Table 1 are representative polyamide pairs of five-membered heterocycles and the DNA pairs that they preferentially bind to, referred to herein as the "pairing rules."
TABLE 1Pairing Rules for Five-Membered HeterocylesDNA base pairPolyamide Pair*recognitionIm/PyG•CPy/ImC•GHp/PyT•APy/HpA•T*Im = N-methyl imidazole; Py = N-methyl pyrrole; Hp = 3-hydroxypyrrole
The fidelity of minor groove recognition by N-terminal Im/Py pairings in hairpin polyamides can be rationalized by a combination of both stabilizing and destabilizing forces which favors the rotamer with N3 in the groove and N-methyl out. Rotation of a terminal Im residue in the opposite conformer, orienting N3 away from the minor groove, would create unfavorable lone pair interactions with the proximal carboxamide oxygen, disrupt a favorable hydrogen bond with the exocyclic amine of G, and project an N-methyl group to the DNA floor which is presumably sterically unfavorable. Specifically, Im/Py distinguishes G-C from C-G and both of these from T-A/A-T base pairs while a Py/Py pair binds both T-A and A-T in preference to G-C/C-G. The exocyclic amino group of guanine imparts G-C specificity to Im/Py pairs through formation of a specific hydrogen bond with N3 of Im. Binding of Py/Py is disfavored at G-C base pairs by destabilizing steric interactions between the C3-H of Py and the guanine amino group (White et al., Chem. Biol. 1997, 4, 569; Kielkopf et al., Nat. Struct. Biol. 1998, 5, 104). The replacement of C3-H of one Py with hydroxyl creates the Hp/Py pair which exploits the steric fit and hydrogen bond acceptor potential of thymine-O2 as well as the destabilizing step c interaction with the bulkier adenine ring to gain specificity for T-A (White et al., Nature 391, 468, 1998; Kielkopf et al., Science 282, 111, 1998).
The five-membered heterocycles described thus far in DNA-binding polyamide oligomers are analogues of the pyrrole ring. Their chemical design mimics the natural products netropsin and distamycin A, molecules which bind the minor groove of DNA (Arcamone, F. et al., Nature 203: 1064, 1964; Pelton, J. G. et al., Proc Natl Acad Sci USA 86: 5723-5727, 1989).
The above pairing rules have been used to design hundreds of synthetic ligands that bind predetermined DNA sequences. However, many sequences remain difficult to target, likely due to sequence dependent microstructure variations in minor groove width or curvature. Furthermore, the specificity of cofacial aromatic amino acid pairings depend on their context (position) within a given hairpin polyamide. For example, Im/Py pairings show comparable specificity for G-C at both terminal and internal positions. Conversely, Hp/Py pairings do not specify T-A at the N-terminus of hairpin polyamides (Ellervik et al., J. Am. Chem. Soc. 2000, 122, 9354). The context dependence of Hp is presumably a result of the conformational freedom inherent to an N-terminal aromatic residue. The absence of a second 'groove-anchoring' carboxamide allows terminal rings to bind DNA in either of two conformations. For a terminal Hp residue, a rotamer with the hydroxyl recognition element oriented away from the floor of the minor groove could be stabilized by intramolecular hydrogen bonding between the C3-OH and the carbonyl oxygen of the 2-carboxamide. For terminal 2-hydroxybenzamide residues, some measure of T-A selectivity was recovered by creating steric bulk at the 6-position to force the hydroxyl recognition element into the groove (Ellervik et al., J. Am. Chem. Soc. 2000, 122, 9354). However, N-terminal pairings capable of binding T-A, with affinity and specificity comparable to those of Im/Py for G-C, are desired.
Efforts have been devoted to extend the ensemble of five-membered heterocycles that are capable of cooperatively pairing with each other to recognize specific DNA base pairs. These efforts have, in part, been motivated by the instability of the Hp heterocycle towards acids and free radicals. Polyamide oligomers containing Hp are susceptible to such degradation, and a robust replacement for use in biological applications is desired.
A search for new five-membered heterocycles and new five-membered heterocycle pairs for sequence determination was recently attempted with little success (Marques, M. et al., Helvetica Chimica Acta 85: 4485-4517, 2002). Using molecular modeling from an X-ray crystallography structure of a polyamide oligomer bound to duplex DNA, analogs of the existing five-membered heterocycles were designed to optimize binding to the curvature and twist of minor-groove DNA. Analogs of Py (1-methyl-1H-pyrazole (Pz) and 1H-pyrrole (Nh)), Im (5-methylthiazole (Nt) and furan (Fr)), and Hip (3-hydroxythiopene (Ht)) were synthesized and investigated in polyamide pairs. Additional sulfur containing pyrrole analogs (4-methylthiazole (Th), 3-methylthiophene (Tn), and thiophene (Tp)) were also studied. The chemical structures of these analogs are shown below:

Six-membered heterocycles represent a new class of heterocycles that may be employed in compounds which bind DNA. Certain small molecule ligands known to bind the minor groove of DNA with relatively high affinities contain six-membered heterocycles and fused heterocycles, such as benzimidazole, imidazopyridines, and indoles (R. L. Lombardy, et al., J. Med. Chem., 39: 1452-1462, 1996; Minehan, T. G. et al. Helv. Chim. Acta, 83: 2197-2213, 2000; Wang, L. et al., Biochemistry, 40: 2511-2521, 2001; Zhang, W. et al., FEBS Lett., 509: 85-89, 2001; Ji, Y.-H. et al., Bioorg. Med, Chem., 9: 2905-2919, 2001; Satz, A. L. et al., J. Am. Chem. Soc., 123: 2469-2477, 2001; Behrens, C. et al., Bioconjugate Chem, 12: 1021-1027, 2001; Matsuba, Y. et al., Cancer Chemother. Pharmacol., Vol. 46: 1-9, 2000).
Hoechst 33258, which comprises a bis-benzimidazole, an N-methylpiperazine, and a phenol moiety, is an example of a fused six-membered cyclic derivative (P. E. Pjura, K. Grzeskowiak, R. E. Dickerson, J. Mol. Biol, 197: 257-271, 1987; M. Teng, N. Usman, C. A. Frederick, A. Wang, Nucleic Acids Res., 16: 2671-2690, 1988; S. Kumar, B. Yadagiri, J Zimmermann, R. T. Pon, J. W. Lown, J. Biomol. Struct. Dyn., 8: 331-357, 1990). The chemical structure of Hoechst 33258 is shown below:

Hoechst 33258 is a highly fluorescent dye which binds the minor groove of DNA at A·T rich tracks. Oligomers of the Hoechst benzimidazoles have been synthesized and studied for DNA recognition (Minchan, T. G. et al., Helvetica Chimica Acta 83: 2197-2213, 2000). These benzimidazole oligomers also show preference for A·T rich sequences, as well as for 5′-WGWWW-3′ and 5′-WCWWW-3′, where W=A or T.
While Hoechst 33258 and its corresponding benzimidazole oligomers bind A·T rich DNA in a 1:1 ratio, such compounds do not recognize specific nucleotide base pairs across the duplex, such as in the pairing rules described above for five-membered heterocyclic polyamide oligomers. Other six-membered heterocyclic DNA binding ligands reported thus far also do not recognize specific mononucleotide base pairs across the duplex.
Thus, a need in the art for a T recognition element using the asymmetric cleft of a T-A base pair as the basis for shape selective discrimination has been identified.


A car navigation system with an FM multi-broadcast signal receiving function has: a function of displaying a current position on a display 17a according to position data which is received through a GPS antenna 12 from a satellite; and an FM multi-data display unit 17 which is arranged on a dash board 31 in front of the driver's seat of a vehicle.

1. Field of the Invention
This invention relates to a car navigation system with an FM multi-broadcast signal receiving function.
2. Related Art
A car navigation system is to guide a vehicle to a destination set even if the driver does not know a map to the destination (a way to the destination). Recently, a car navigation system has been proposed in the art which is designed as follows: By receiving road data superposed on an FM broadcast signal, the driver foresees a direction of movement and how crowded a road to the destination is, and, if necessary, sets a detour route.
In general, in a car navigation system, its display is arranged near the console beside the driver's seat or near the part of the dash board which is located away from the driver's seat, and its FM receiver incorporating an FM multi-data display unit is arranged in the console. Hence, when necessary, the driver must look aside while confirming the road condition in the direction of drive movement, and in addition he must read the data displayed on the FM multi-data display unit built in the FM receiver. Hence, the frequency of the driver's looking aside is high or the time required for the driver to look aside is long, which increases the possibility of occurrence of vehicle accidents.

Car navigation system with FM multi-broadcast signal receiving function


A circuit includes a first amplifier having first and second inputs and first and second output, first and second input capacitors, a first feedback capacitor selectively coupled between the first input and the first output, and a second feedback capacitor selectively coupled between the second input and the second output. During a second phase of operation, the first and second feedback capacitors are decoupled from the output and the first amplifier is configured to sample an input common mode voltage, an output common mode voltage, and an input offset voltage of the first amplifier on the first and second input capacitors. During a first phase of operation, the first feedback capacitor is coupled between the input and the output, the second feedback capacitor is coupled between the input and the output, and the first amplifier is configured to amplify a differential input signal provided across the first and second inputs.

A variety of circuits to control and drive electric motors are known. In some cases, small differential voltages may need to be sensed on high common mode voltages, for example in sensing motor winding current. The input common mode voltage can have large swings between a high input voltage and ground, and small differential voltages may need to be sensed.

Capacitive amplifier circuit with high input common mode voltage and method for using the same


Methods, apparatus, and systems for intravascular analysis combine at least three analytical modalities. In one implementation, intravascular ultrasound, optical coherence tomography, and near infrared spectroscopy are combined to enable detection of multiple, different abnormalities in the arterial morphology during a single intravascular procedure.

Atherosclerosis is a vascular disease characterized by the modification of the walls of blood carrying vessels. This modification can take the form of thickening of the vessel wall, eventually forming what are commonly referred to as "plaques." The mechanisms corresponding to the formation, progression, stabilization, or rupture of these plaques and their effects on humans has been an area of intense research in intravascular medicine. With the advent of interventional cardiology and percutaneous diagnostic and treatment procedures, the patient with coronary atherosclerotic disease was no longer required to automatically submit to coronary by-pass surgery—an extremely invasive procedure with attendant risks and extended recovery time. Coronary stents were developed to revascularize narrowed (stenosed) vessels and millions of theses devices have been placed in patients worldwide. However, current statistics show that, while patient comfort and quality of life has been improved, treatment of coronary atherosclerotic disease by stenting has not significantly reduced the patient mortality. Patients treated with stents are still dying suddenly of heart attack.
Much more is now known about coronary disease than even a decade ago, but there are still many questions to be answered. From retrospective autopsy studies on heart attack victims, it has been shown (ref Virmani) that there is often a portion of the coronary artery tree that is completely blocked by a thrombosis, or blood clot. The thrombosis is typically in the vicinity of a plaque in the vessel wall. Referred to as the "culprit lesion," it would be this blockage that would cut off the blood supply to a portion of the heart, resulting in death of heart muscle tissue and possibly death of the individual. Certain plaques contain material which, when it comes into contact with blood, causes thrombogenesis, or clot formation. These plaques seem to have formed a reservoir, or core, of thrombogenic material behind a layer of fibrous tissue ("cap"), analogous to an abscess. Through some process or set of processes, the integrity of the fibrous layer can become compromised, whereby blood can eventually come into contact with the thrombogenic core. This can be a sudden event, where the patient had no prior warning or even symptoms. If one categorizes plaques broadly as stable—where they may still progress slowly and eventually restrict the vessel—and unstable—those that can change their status rapidly, among the key questions is: "How can we tell the difference?"
Historically, the search for atherosclerotic disease has been a search for the narrowing in the opening or "lumen" of the vessel. Angiography is one of the oldest intravascular technologies employed for this purpose. The technique typically employs a catheter, introduced percutaneously into the vasculature, that is used to inject a contrast agent, consisting of a radio opaque dye, into the blood vessels of interest. Using x-rays, a two dimensional live (cine) or still image of the vasculature can be obtained. The vessel lumen is visible wherever the contrast agent is able to flow. From these images, one can determine the size of the lumen and the presence of any narrowing or blockage. The presence of a plaque can sometimes be inferred by a diffuse lumen boundary. Despite being standard of care for many years and forming the basis for most therapy decisions, angiography alone suffers from some limitations. First, vessel narrowing is not necessarily rotationally isotropic. With only a single view angle from which to form the 2-D image, areas of narrowing can be underestimated or missed entirely. To obtain images from multiple viewpoints requires more time and exposure of the patient to contrast and x-rays. The nature of the image as a "lumenogram," along with limited spatial resolution, make it difficult, if not impossible, to make any statement about the characteristics of the tissue in the vessel wall. For example, it is impossible to distinguish between a fibrotic plaque and one with a necrotic, lipid filled core.
Intravascular ultrasound (IVUS) has emerged, in the last 15 years, as an imaging technology to measure tissue structural characteristics, in particular for blood vessels. IVUS employs a specially designed catheter, with an acoustic transducer at the distal tip, to send and receive ultrasonic signals. So called, "mechanical" IVUS catheters consist of a flexible polymer outer sheath, inside of which is a core that rotates and pulls back through the vessel, generating a series of circumferential scans of the vessel wall. The core typically consists of an RF transmission line, connecting the transducer at the distal tip to drive and receive electronics. A helically wound wire cable is typically used to transmit torque from a rotary motor, through the core to the distal tip, to ensure rotation of the tip with consistent angular velocity. Ultrasonic waves are back scattered by human tissue. The strength of the back scatter is a function of tissue properties, including density. The signal returning from tissue from a rotating IVUS catheter can be represented as a radar plot with a 360 degree view of a section of the vessel and the radial dimension showing the strength of the signal return as a function of distance from the center of the catheter. An advantage of IVUS is that it allows one to obtain an image of the inner walls of the vessel, even through intervening blood. With axial image resolution of 100-200 microns and imaging depth of greater than 5 mm, various structures within the vessel wall can be visualized, including areas of calcification and thickening of the arterial wall. Also, the boundary between the lumen and the vessel intima as well as that between the media and the adventitia can be visualized with accuracy good enough to calculate lumen dimensions and the area of plaques, or "plaque burden."
Optical coherence tomography (OCT) is an emerging technology that also provides structural information similar to IVUS. OCT depends on the scattering of light by tissue and uses the coherence properties of light, for example, using a Michelson interferometer, to determine the distance at which a scattering event occurred. The technique is similar to IVUS in that a catheter is moved over a guidewire into the blood vessel to a region of interest and then the core of the catheter is pulled back to scan the artery. However, there are several key differences. For example, the OCT signal cannot penetrate blood, requiring that the blood be cleared from the area of the vessel being imaged. A variety of methods have been employed to accomplish this, the most promising and least dangerous to the patient being a non-occlusive flush, using a bolus of saline/contrast mix. This method provides several seconds in which to obtain an image of a vessel segment.
Another class of intravascular analysis systems uses chemical analysis modalities. These approaches generally rely on optical spectral analysis including near infrared (NIR), Raman, and fluorescence spectral analysis.
Near Infrared Spectroscopy (NIR or NIRS) is a technique, again using light in the near infrared region of the spectrum, intended not to image the physical structure of the artery, but the chemical constituents, specifically cholesterol, of the arterial wall. Unlike OCT, NIR can perform such measurement through blood. Operation of a NIR catheter is very similar to that of IVUS with regard to insertion into the patient and pullback and acquisition of data. The result is a two dimensional map of the cholesterol, or lipid, content of the artery.
NIRS utilizes an intravascular optical catheter which, similarly to IVUS, is driven by a pullback and rotation unit that simultaneously rotates the catheter head around its longitudinal axis while withdrawing the catheter head through the region of the blood vessel of interest.
During this pullback operation, the spectral response of the inner vessel walls is acquired in a raster scan operation. This provides a spatially-resolved spectroscopic analysis of the region of interest. The strategy is that by determining the spectroscopic response of blood vessel walls, the chemical constituents of those blood vessel walls can be determined by application of chemometric analysis, for example.
In Raman spectral analysis, the inner walls of the blood vessel are illuminated by a narrow band, such as laser, signal. The Raman spectral response is then detected. This response is generated by the inelastic collisions betweens photons and the chemical constituents in the blood vessel walls. This similarly produces chemical information for the vessel walls.
Hybrid IVUS/optical catheters have been proposed. For example, in U.S. Pat. No. 6,949,072, which in incorporated herein by this reference in its entirety, a "device for vulnerable plaque detection" is disclosed. Specifically, this patent is directed to intravascular probe that includes optical waveguides and ports for the near infrared analysis of the blood vessel walls while simultaneously including an ultrasound transducer in the probe in order to enable IVUS analysis of the blood vessel walls.

Multimodal catheter system and method for intravascular analysis


A polishing cloth has a surface layer stacked over a base material. The surface layer is made of a foamed layer and a non-foamed layer, the foamed layer including air bubble cells and the non-foamed layer having an externally exposed surface where linear cuts are formed. These linear cuts reach the air bubble cells such that the air bubble cells communicate with the exterior through the linear cuts. These linear cuts are controlled to be 10 μm or less in length.

This invention relates to a polishing cloth and more particularly to a polishing cloth suited to the final polishing of hard disk substrates and silicon wafers.
It has been known to use a polishing cloth of the type produced by removing the non-foamed layer (referred to as the skin layer) which constitutes a surface portion of the foamed layer by buffing or by means of a knife so as to expose air bubble cells generated inside the foamed layer on the surface by 1–1000 μm. This was both because it is necessary to hold the polishing liquid in the air bubble cells and because the surface of a foamed resin material normally produced is not sufficiently smooth and flat. Surface roughness due to air bubble cells affects the surface flatness adversely, and it is becoming a serious problem because surface roughness results on surfaces polished by such a polishing cloth. The problem of surface roughness is recently becoming particularly important in the technical field of final polishing of hard disk substrates and silicon wafers and it is becoming essential to reduce such surface roughness.
In view of the problem of reducing surface roughness, Japanese Patent 3,187,769 disclosed the technology of using sandpaper or the like with fine particles to buff the surface of a polishing cloth after air bubbles are exposed, and Japanese Patent Publication Tokkai 2001-62704 disclosed the technology of minutely buffing the skin layer without exposing air bubbles on the surface to improve surface flatness. The former technology is not satisfactory because the surface flatness cannot be improved over a certain limit because air bubbles are exposed on the polishing surface. Neither is the latter technology satisfactory but it is because the polishing liquid cannot be retained.


The system and method enables the automatic routing of email and information corresponding to email to a database. The system and method also enables the filtering of email, determination of a protocol based on the filtering, and the transfer of the email according to the determined protocol.

1. Field of the Invention
This invention relates generally to computer networks, and more particularly relates to automatic data forwarding via a computer network to a server computer.
2. Description of the Background Art
Data accessibility and consistency are significant concerns of computer users. For example, when a user maintains multiple computer sites, e.g., a work site and a home site, a user risks having redundant versions of a document or an email. If one of the redundant copies is modified, then the copies become effectively inconsistent. If the user fails to notice any inconsistency, interparty miscommunication or data loss may result. The user must then spend substantial time attempting to reconcile the inconsistent versions and addressing any miscommunications.
Data inconsistency is often caused when the redundant copies of the document or email are maintained on different sites, and when one or more of the redundant copies is inaccessible. For example, if one of versions is maintained on a computer site that is protected by a network security system such as a conventional firewall, e.g., the work computer site, the security system may prevent the user from accessing the copy. Without access to all computer sites, the user is unable to confirm that the version on an accessible site is the most recent draft.
The problems of data inconsistency and inaccessibility arise in the area of electronic mail (email). For example, a user might maintain email databases at a work computer site and at a home computer site. Based on the security systems implemented, a traveling user currently working from a remote terminal may not have access rights to the work computer site or the necessary dedicated application programs to pass the intranet security. Thus, the user may not be able to review the email maintained at the work computer site and thus cannot read or respond to work emails until returning to work. Still further, when maintaining several accessible sites, the traveling user is burdened to maintain a record of all procedures and passwords to overcome the security system of each site.
These problems are further exacerbated when using email programs from different vendors and which implement different protocols. For example, the Netscape Navigator™ e-mail client and the Outlook Express™ email client each manage email across computer networks. However, each email client uses different formats, stores emails in different files and implements different protocols. Thus, the emails are not readily interchangeable.
Therefore, a system and method are needed for providing users with email consistency and accessibility across a computer network.

System and method for automatically forwarding email and email events via a computer network to a server computer


A color, high-throughput, ferroelectric liquid crystal-based light valve comprising a light input, a light output, a beam splitter, a color separator, reflective spatial light modulators, and a switchable half-wave plate. Light polarized parallel to a first direction is received through the light input. Light from the light input and reflected by the spatial light modulators is output from the light output. The reflective spatial light modulators are structured as a quarter-wave plates and each has a principal axis that switches through an angle xcfx86. The beam splitter has orthogonal directions of maximum transmissivity and maximum reflectivity, one of which is parallel to the first direction. The beam splitter is located and aligned relative to the light input, the light output, and the color separator to transmit or reflect the light from the light input towards the color separator, and to reflect or transmit, respectively, towards the light output the light reflected by each of the spatial light modulators and having a direction of polarization substantially orthogonal to the first direction. The switchable half-wave plate is located between the beam splitter and the color separator, is structured as a half-wave plate and has a principal axis that switches through an angle xcex8, substantially equal to xcfx86/2. The switchable half-wave plate inverts the sense of the light valve during the balance period of each display period to enable the light valve to generate a positive image, and therefore be illuminated, during the balance period in addition to during the illumination period.

The invention relates to reflective ferroelectric liquid crystal-based light valves such as those used in video displays and in particular relates to such light valves for forming color images and having a substantially increased light throughput.
A need exists for various types of color video and graphics display devices with improved performance and lower cost. For example, a need exists for miniature color video and graphics display devices that are small enough to be integrated into a helmet or a pair of glasses so that they can be worn by the user. Such wearable color display devices would replace or supplement the conventional displays of computers and other devices. A need also exists for a replacement for the conventional cathode-ray tube used in many display devices including computer monitors, conventional and high-definition television receivers and large-screen displays. Both of these needs can be satisfied by display devices that incorporate a light valve that uses as its light control element three reflective spatial light modulators, each based on a ferroelectric liquid crystal (FLC) material.
A FLC-based spatial light modulator is composed of a layer of a FLC material, preferably a surface-stabilized FLC material, sandwiched between a transparent electrode and a reflective electrode that is segmented into an array of pixel electrodes to define the picture elements (pixels) of the spatial light modulator. The reflective electrode is located on the surface of a silicon substrate that also accommodates the drive circuits that derive the drive signals for the pixel electrodes from an input video signal.
The direction of an electric field applied between each pixel electrode and the transparent electrode determines whether or not the corresponding pixel of the spatial light modulator rotates the direction of polarization of light reflected by the pixel. The reflective spatial light modulator is constructed as a quarter-wave plate so that the polarized light reflected by the pixels of the spatial light modulator is either rotated by 90xc2x0 or not depending on the direction of the electric field applied to each pixel. A polarization analyzer is in the optical path of the light reflected by the spatial light modulator. The polarization analyzer is aligned to either: 1) transmit the polarized light which has rotated and absorb the polarized light which as not been rotated; or 2) transmit the polarized light which as not rotated and to absorb the polarized light which has been rotated. The resulting optical characteristics of each pixel of the spatial light modulator are binary: the light reflected by the pixel either is transmitted through the polarization analyzer (its 1 state) or is absorbed by the polarization analyzer (its 0 state), and therefore appears light or dark, depending on the direction of the electric field.
To produce the grey scale required for conventional display devices, the apparent brightness of each pixel is varied by temporally modulating the light transmitted by each pixel. The light is modulated by defining a basic time period that will be called the illumination period of the spatial light modulator. The pixel electrode is driven by a drive signal that switches the pixel from its 1 state to its 0 state. The duration of the 1 state relative to the duration of the illumination period determines the apparent brightness of the pixel.
Ferroelectric liquid crystal-based spatial light modulators suffer the disadvantage that, after each time the drive signal has been applied to a pixel electrode to cause the pixel to modulate the light passing through it, the DC balance of the pixel must be restored. This is typically done by defining a second basic time period called the balance period, equal in duration to the illumination period, and driving the pixel electrode with a complementary drive signal having 1 state and 0 state durations that are complementary to the 1 state and 0 state durations of the drive signal during the illumination period. The illumination period and the balance period collectively constitute a display period. To prevent the complementary drive signal from causing the display device to display a substantially uniform, grey image, the light source illuminating the light valve is modulated, either directly or with a shutter, so that the light valve is only illuminated during the illumination period, and is not illuminated during the balance period. However, modulating the light source as just described reduces the light throughput of the light valve to about half of that which could be achieved if DC balance restoration were unnecessary. This means that a light source of approximately twice the intensity, with a corresponding increase in cost, is necessary to achieve a given display brightness. Additionally or alternatively, projection optics with a greater aperture, also with a corresponding increase in cost, are necessary to achieve a given brightness.
FIG. 1A shows part of a conventional display device 5 incorporating a conventional reflective light valve 10 that includes the reflective spatial light modulator 12. Other principal components of the light valve are the polarizer 14, the beam splitter 16 and the analyzer 18. The light valve is illuminated with light from the light source 20, the light from which is concentrated on the polarizer using a reflector 22 and collector optics 24. The light output by the light valve passes to the imaging optics 26 that focus the light to form an image (not shown). The light valve 10, light source 20 and imaging optics may be incorporated into various types of display device, including miniature, wearable devices, cathode-ray tube replacements, and projection displays.
Light generated by the light source 20 enters the light valve 10 by passing through the polarizer 14. The polarizer polarizes the light output from the light source. Alternatively, a polarized light source (not shown) can be used and the need for the polarizer 14 would be eliminated. The beam splitter 16 then reflects a fraction of the polarized light output from the polarizer towards the spatial light modulator 12. The beam splitter can additionally or alternatively be a polarizing beam splitter configured to reflect light having a direction of polarization parallel to the direction of polarization of the polarizer 14 towards the spatial light modulator 12. The spatial light modulator 12 is divided into a two-dimensional array of picture elements (pixels) that define the spatial resolution of the light valve 10. Light reflected from the spatial light modulator can pass to the beam splitter 16 which transmits a fraction of the reflected light to the analyzer 18. If the beam splitter is a polarizing beam splitter, however, only light having a direction of polarization orthogonal to the direction of polarization imparted by the polarizer will be transmitted and the need for an independent analyzer would be eliminated.
The direction of an electric field in each pixel of the spatial light modulator 12 determines whether or not the direction of polarization of the light reflected by the pixel is rotated by 90xc2x0 relative to the direction of polarization of the incident light. The light reflected by each pixel of the spatial light modulator passes through the beam splitter 16 and the analyzer 18 and is output from the light valve 10 through the imaging optics 26 depending on whether or not its direction of polarization was rotated by the spatial light modulator.
More specifically, the polarizer 14 polarizes the light generated by the light source 20 that passes through the collector optics 24 either directly or after reflecting off reflector 22. The polarization is preferably linear polarization. The beam splitter 16 reflects the polarized light output from the polarizer towards spatial light modulator 12, and the polarized light reflected from the spatial light modulator transmits to the analyzer 18 through the beam splitter 16. The direction of maximum transmission of the analyzer is orthogonal to that of the polarizer in this example.
For purposes of this description, the terms parallel and orthogonal will be used to describe directions of polarization and directions of maximum transmissivity and maximum reflectivity. When these terms are used within this description, it is understood that they relate to the optical characteristics of the light and of the various components that comprise the light valve and not necessarily to their spatial relationships. For example, when polarized light reflects from a mirror at an angle of incidence of 45xc2x0, the polarized light is reflected at an angle of 90xc2x0 relative to the incident light. Even though the incident light and the reflected light are spatially orthogonal to one another, the direction of polarization of the reflected light will be optically unchanged from the direction of polarization of the incident light. Thus, the direction of polarization of the reflected light may be said to be parallel to the direction of polarization of the incident light. In addition, as used herein the term parallel shall include directions that are both parallel and anti-parallel, i.e., having a direction 180xc2x0 opposed, to the original direction.
The spatial light modulator 12 is composed of a transparent electrode 28 deposited on the surface of a transparent cover 30, a reflective electrode 32 located on the surface of the semiconductor substrate 34, and a ferroelectric liquid crystal layer 36 sandwiched between the transparent electrode 28 and the reflective electrode 32. The reflective electrode is divided into a two-dimensional array of pixel electrodes that define the pixels of the spatial light modulator and of the light valve. A substantially reduced number of pixel electrodes are shown to simplify the drawing. For example, in a light valve for use in a large-screen computer monitor, the reflective electrode could be divided into a two-dimensional array of 1600xc3x971200 pixel electrodes. An exemplary pixel electrode is shown at 38. Each pixel electrode reflects the portion of the incident polarized light that falls on it towards the beam splitter 16.
A drive circuit (not shown), which may be located in the semiconductor substrate 34, applies a drive signal to the pixel electrode 38 of each pixel of the spatial light modulator 12. The drive signal has two different voltage levels, and the transparent electrode 28 is maintained at a fixed potential mid-way between the voltage levels of the drive signal. The potential difference between the pixel electrode and the transparent electrode establishes an electric field across the part of the liquid crystal layer 36 between the pixel and transparent electrodes. The direction of the electric field determines whether the liquid crystal layer rotates the direction of polarization of the light reflected by the pixel electrode, or leaves the direction of polarization unchanged.
Since light passes through the reflective spatial light modulator twice, once before and once after reflection by the reflective pixel electrodes, the reflective spatial light modulator 12 is structured as a quarter-wave plate. The thickness of the layer of ferroelectric liquid crystal material in the liquid crystal layer 36 is chosen to provide an optical phase shift of 90xc2x0 between light polarized parallel to the director of the liquid crystal material and light polarized perpendicular to the director. The liquid crystal material is preferably a Smectic C* surface stabilized ferroelectric liquid crystal material having an angle of 22.5xc2x0 between its director and the normal to its smectic layers. Reversing the direction of the electric field applied to such a liquid crystal material switches the director of the material through an angle of about 45xc2x0. Consequently, if the director is aligned parallel to the direction of maximum transmission of the analyzer 18 with one polarity of the electric field, reversing the direction of the electric field will rotate the direction of polarization of light reflected by the pixel through 90xc2x0. This will align the direction of polarization of the light perpendicular to the direction of maximum transmission of the analyzer, and will change the pixel from its 1 state, in which the pixel appears bright, to its 0 state, in which the pixel appears dark.
In a miniature, wearable display, the imaging optics 26 are composed of an eyepiece that receives the light reflected by the reflective electrode 32 and forms a virtual image at a predetermined distance in front of the user (not shown). In a cathode-ray tube replacement or in a projection display, the imaging optics are composed of projection optics that focus an image of the reflective electrode on a transmissive or reflective screen (not shown). Optical arrangements suitable for use as an eyepiece or projection optics are well known in the art and will not be described here.
Since the direction of maximum transmission of the analyzer 18 is orthogonal to the direction of polarization defined by the polarizer 14, light whose direction of polarization has been rotated through 90xc2x0 by a pixel of the spatial light modulator 12 will pass through the analyzer and be output from the light valve 10 whereas light whose direction of polarization has not been rotated will not pass through the analyzer. The analyzer only transmits to the imaging optics 26 light whose direction of polarization has been rotated by pixels of the spatial light modulator. The pixels of the spatial light modulator will appear bright or dark depending on the direction of the electric field applied to each pixel. When a pixel appears bright, it will be said to be in its 1 state, and when the pixel appears dark, it will be said to be in its 0 state.
The direction of maximum transmission of the analyzer 18 can alternatively be arranged parallel to that of the polarizer 14, and a non-polarizing beam splitter can be used as the beam splitter 16. In this case, the spatial light modulator 12 operates in the opposite sense to that just described.
To produce the grey scale required by a display device notwithstanding the binary optical characteristics of the pixels of the light valve 10, the apparent brightness of each pixel is varied by temporally modulating the light reflected by the pixel, as described above. The drive circuit (not shown) for each pixel of the spatial light modulator determines the duration of the 1 state of the pixel in response to a portion of the input video signal 40 corresponding to the location of the pixel in the spatial light modulator.
FIGS. 1B-1F illustrate the operation of the exemplary pixel 38 of the conventional light valve 10 shown in FIG. 1A during three consecutive display periods. The remaining pixels operate similarly. In one embodiment of a conventional light valve, each display period corresponded to one frame of the input video signal 40. In another embodiment, each display period corresponded to a fraction of one frame of the input video signal. Each display period is composed of an illumination period (ILLUM) and a balance period (BALANCE) having equal durations, as shown in FIG. 1B.
FIG. 1C shows the drive signal applied to the exemplary pixel electrode 38. The transparent electrode 28 is held at a voltage level of V/2, so that changing the voltage level on the pixel electrode from 0 to V reverses the direction of the electric field applied to the ferroelectric liquid crystal layer 36. The level of the drive signal is V for a first temporal portion 1TP of each illumination period. The level of the drive signal is 0 for the second temporal portion 2TP constituting the remainder of the illumination period, and also for the first temporal portion 1TP of the subsequent balance period. The first temporal portion of the balance period has a duration equal to the first temporal portion of the illumination period. However, the level of the drive signal is 0 during the first temporal portion of the balance period, whereas the level of the drive signal is V during the first temporal portion of the illumination period. Finally, the level of the drive signal changes to V for the second temporal portion 2TP constituting the remainder of the balance period. Consequently, during the balance period, the level of the drive signal is 0 and V for times equal to the times that it was at V and 0, respectively, during the illumination period. As a result, the electric field applied to the liquid crystal material of the pixel averages to zero over the display period.
In the example shown, the duration of the first temporal portion 1TP of the drive signal is different in each of the three illumination periods. The duration of the first temporal portion, and, hence, of the second temporal portion, of each illumination period depends on the voltage level of the corresponding sample of the input video signal 40.
FIG. 1D shows the effect of the spatial light modulator 12 on the direction of polarization of the light impinging on the analyzer 18. The direction of polarization is indicated by the absolute value of the angle xcex1 between direction of polarization of the light impinging on the analyzer and the direction of maximum transmissivity of the analyzer. The analyzer transmits light having an angle xcex1 close to zero and absorbs light having an angle xcex1 close to 90xc2x0. In each display period, the angle xcex1 has values corresponding to the pixel being bright and dark for equal times due to the need to restore the DC balance of the pixel.
FIG. 1E shows the condition of a fast-acting light source 20. The light source is ON throughout the illumination period of each display period, and is OFF during the following balance period. Alternatively, the light source could remain on and a shutter (not shown) could be used to control whether the light generated by the light source illuminates the spatial light modulator 12. For example, an open shutter would correspond to the light source being ON and a closed shutter would correspond to the light source being OFF.
FIG. 1F shows the light output from the exemplary pixel of the light valve 10 controlled by the pixel electrode 38. Light is output from the pixel only during the first temporal portion of the illumination period of each display period. No light is output during the second temporal portion of the illumination period. Moreover, no light is output during the balance period of the display period because the light source 20 is OFF during the balance period.
The light valve 10 shown in FIG. 1A can also be adapted to provide a colored light output to the imaging optics 26. One way that this can be done is by replacing the xe2x80x9cwhitexe2x80x9d light source 20 with three colored light sources such as a red, blue and green LEDs (not shown), each illuminating the spatial light modulator 12 sequentially. This would require a balance period after each sequential illumination period. Another way that a colored light output can be provided is by replacing the single reflective spatial light modulator 12 shown in FIG. 1A with three reflective spatial light modulators and a color separator for separating the light into three component colors.
An example of one such color configuration is depicted in FIG. 2. Regarding this figure and those that follow, it is noted that identical reference numerals are used to designate identical or similar elements throughout the several views, and that elements are not necessarily shown to scale. In FIG. 2, the color separator is a series of three dichroic plates 42,43,44, each having an associated reflective spatial light modulator 12. Each of the dichroic plates is configured to reflect light in a band of wavelengths (colorband) particular to that dichroic plate and to pass the remaining wavelengths of light. Thus, if the light source 20 is a xe2x80x9cwhitexe2x80x9d light, emitting visible light across the entire visible color spectrum, a particular portion of the color spectrum may be reflected by each dichroic plate its associated reflective spatial light modulator simultaneously. This eliminates the need for sequential illumination and improves the perceived brightness of the color pixels passing through the analyzer.
For example, the dichroic plate 42 nearest the beam splitter 16 might reflect red-colored light toward its associated spatial light modulator 12 while the center dichroic plate 43 reflects green-colored light toward its associated spatial light modulator and the dichroic plate remote from the beam splitter 44 reflects blue-colored light towards its spatial light modulator. When the light source 20 is ON, as shown if FIG. 2, the colored light reflected by the dichroic plates passes to each of the three reflective spatial light modulators 12. Each of the three reflective spatial light modulators is capable of reflecting pixels of the colored light back at its associated dichroic plate in a manner consistent with the above description of the operation of the spatial light modulator shown in FIG. 1A.
The majority of the colored light reflected by each of the spatial light modulators 12 will be reflected by its associated dichroic plate toward the analyzer 18 since the light reflected by each spatial light modulator will retain the characteristic wavelengths of light originally reflected by its respective dichroic plate. When the combined colored light from each of the three reflective spatial light modulators 12 passes through the analyzer, a full color image can be formed by the imaging optics 26.
FIG. 3 depicts the use of a color separation cube 46, sometimes known as an x-cube or crossed-dichroic cube, as a color separator in place of the three dichroic plates. As with the three dichroic plates, the color separation cube separates three distinct color bands from the xe2x80x9cwhitexe2x80x9d light created by light source 20 and directs each of the color bands to a particular spatial light modulator 12. The color separation cube 46 also recombines the light reflected from each of the spatial light modulators 12 and directs the combined light toward the analyzer 18. The use of a color separation cube allows for a more compact design utilizing three spatial light modulators than can be achieved using three separate dichroic plates.
FIG. 4 depicts the use of a third type of color separator, a three-prism color separator 48 (sometimes known as a Philips cube or Philips prism), in a light valve utilizing three spatial light modulators to generate a color image. The design and use of a three-prism color separator is described in detail in U.S. Pat. No. 5,644,432, the contents of which are incorporated herein by reference. Like the previously described color separators, the three-prism color separator separates three distinct color bands from the xe2x80x9cwhitexe2x80x9d light created by light source 20 and directs each of the color bands to a particular spatial light modulator 12. The three-prism color separator 48 also recombines the light reflected from each of the spatial light modulators 12 and directs the combined light toward the analyzer 18. The three-prism color separator has the advantage over the three dichroic plates and the color separation cube in that it typically does a better job of recombining the reflected light from each of the spatial light modulators into a single color image.
While the use of dichroic plates, a color separation cube, or three-prism color separator allows color images to be formed by three ferroelectric liquid crystal-based spatial light modulators and a xe2x80x9cwhitexe2x80x9d light source, each of the spatial light modulators still suffers the disadvantage that the DC balance of the pixel must be restored. As with the single spatial light modulator discussed above, DC balance is typically achieved by defining a balance period and driving the pixel electrode with a complementary drive signal having 1 state and 0 state durations that are complementary to the 1 state and 0 state durations of the drive signal during the illumination period. The xe2x80x9cwhitexe2x80x9d light source is typically modulated during the balance period to prevent the complementary drive signal from causing the display device to display a substantially uniform, grey image. Modulating the light source as just described, however, reduces the light throughput of the light valve to about half of that which could be achieved if DC balance restoration were unnecessary. This means that a light source of approximately twice the intensity, with a corresponding increase in cost, is necessary to achieve a given display brightness. Additionally or alternatively, projection optics with a greater aperture, also with a corresponding increase in cost, are necessary to achieve a given brightness.
Consequently, what is needed is a color light valve utilizing three reflective ferroelectric liquid crystal spatial light modulators that can remain illuminated during the balance period so that the light throughput of the light valve can be approximately twice that of a conventional, color light valve utilizing three spatial light modulators.
The invention provides a high throughput color light valve that comprises a light input, a light output, a beam splitter, a color separator, a switchable half-wave plate, and reflective ferroelectric liquid crystal based spatial light modulators. Light having a direction of polarization parallel to a first direction is received through the light input. The light received at the light input is output from the light output after reflection by at least one of the spatial light modulators. The reflective spatial light modulators are each structured as a quarter-wave plate and each has a principal axis that independently switches through an angle of rotation substantially equal to xcfx86. The color separator is configured to separate the light received at the light input into colorbands, and also to distribute the colorbands to the spatial light modulators. The beam splitter is located and aligned relative to the light input, the light output, the color separator and the spatial light modulators either to reflect or transmit the light received at the light input towards the color separator, and transmit or reflect, respectively, towards the light output the light reflected by the spatial light modulators. The switchable half-wave plate is located between the beam splitter and the color separator, is structured as a half-wave plate, and has a principal axis that switches through an angle of rotation xcex8 substantially equal to xcfx86/2.
The spatial light modulators may include a first, second, and third spatial light modulator, and the color separator may separate a first, second, and third color waveband from the light received at the light input. The beam splitter may include a polarizing beam splitter with orthogonal directions of maximum transmissivity and maximum reflectivity, one of the directions being parallel to the first direction.
The switchable half-wave plate may include a pair of opposed transparent electrodes and a layer of liquid crystal material sandwiched between the electrodes. The liquid crystal material may be a ferroelectric liquid crystal material or a nematic liquid crystal material. Alternatively, the direction of the principal axis of the switchable half-wave plate may be mechanically switched.
The color separator may include three dichroic plates, a color separation cube, or a three-prism color separator.
The invention also provides a method of increasing the light throughput of a multi-color component reflective light valve that requires DC balancing. In the method, a reflective light valve is provided that includes a first, second, and third reflective spatial light modulator and a polarizing beam splitter. The polarizing beam splitter has orthogonal directions of maximum transmissivity and maximum reflectivity, one of which defines the direction of polarization of light incident on the reflective spatial light modulators, the other of which defines the direction of polarization of light output from the light valve. Each of the spatial light modulators has a principal axis independently switchable between a first direction and a second direction. The second direction is substantially at an angle xcfx86 to the first direction. Also provided is a switchable half-wave plate that has a principal axis switchable between a third direction and a fourth direction. The fourth direction is at an angle xcex8 to the third direction.
The switchable half-wave plate is inserted into the light valve between the polarizing beam splitter and the color separator with the third direction aligned parallel to the first direction. The spatial light modulators are operated in a first time period and a second time period equal to the first time period with each principal axis independently in the first direction for a portion of the first time period, in the second direction for the remainder of the first time period and a portion of the second time period, and in the first direction for the remainder of the second time period. The portion of the second time period is equal in duration to the portion of the first time period, and the portion of the second time period and the remainder of the second time period are in any temporal order. The switchable half-wave plate is operated with its principal axis in the third direction through the first period and in the fourth direction through the second period, and with the angle xcex8 substantially equal to xcfx86/2.
A switchable half-wave plate may be provided in which the principal axis switches between the third direction and the fourth direction in a switching time, and the method may additionally comprise illuminating the light valve with light, and reducing the intensity of the light during the switching time of the switchable half-wave plate.
Switching the switchable half-wave plate inverts the sense of the light valve relative to the direction of the electric field applied to the liquid crystal material of the spatial light modulator. When the first time period and the second time period correspond to the illumination period and the balance period of a display period, inverting the sense of the light valve during the balance period enables a display device incorporating the light valve to generate a positive image in both the illumination period and the balance period of the display period. Accordingly, the light valve can be illuminated during both the illumination period and the balance period. This almost doubles the light throughput of the light valve according to the invention compared with a conventional light valve.

Color reflective ferroelectric liquid crystal light valve with three spatial light modulators and increased light throughput


In the case of a surgical instrument for performing an operation, the surgical instrument is intended to consist of a ceramic material, preferably in one piece.

The present invention relates to a surgical instrument for performing operations.
Surgical instruments are available on the market in a variety of forms and designs. Generally used for surgical instruments are metallic materials, which are extremely expensive. Furthermore, metal also has further disadvantages with respect to hygiene requirements, since metal has a tendency to oxidize or the like. Furthermore, metallic surgical instruments must be cleaned and sterilized very intensively.
Disposable instruments in particular are currently produced at least partially from plastic. Known, for example, are disposable scalpels which have a plastic handle with a metal knife molded onto it. Diamond knives in a steel holder are also known. Since they are used only once, such surgical instruments are extremely expensive.
Furthermore, electric current is being used increasingly in surgery. Mention may be made just by way of example of electrocoagulation, in which high-frequency alternating currents are applied to destroy small areas of tissue. In this way, pedicellated polyps, ulcers and the like can be removed both from the outer skin and in body cavities. In electrocoagulation, a spark is produced, causing deep burning in an isolated point or line. This separates the tissue or attaches it (for example in the case of retinal detachment) and at the same time has a hemostatic effect by coagulation.
Even the sealing of blood vessels is generally performed today using so-called bipolar surgical instruments.

Surgical instrument of a ceramic material and process for forming same

SLG Kunststoff-Fabrik und Formenbau GmbH


A video encoding/decoding apparatus, a deblocking filter and filtering method based on intra-prediction directions for same, and recording media are disclosed, and the deblocking filter includes: a boundary strength determiner for determining strength of boundary of current block; an intra-block identifier for confirming intra-block identity of a subblock enclosing first pixel at a certain location with reference to the boundary; an intra-prediction direction identifier for identifying an intra-prediction direction of the subblock if the subblock is identified as an intra-block; a filtering pixel selection unit for selecting pixels for filtering based on the first pixel and the identified intra-prediction direction; and a filtering unit for filtering in horizontal direction, vertical direction, or diagonal direction depending on the intra-prediction direction and relationships between pixel values of the selected pixels to eliminate deblocking artifacts within diagonal edges at a boundary between blocks by deblocking filtering in the intra-prediction direction.

The descriptions in this section merely provide background information related to the present disclosure and may not constitute prior art.
Generally, in video codecs such as MPEG and H.264, video compression is performed in the basic unit of macroblock which has 16 pixels horizontally by 16 pixels vertically. Such macroblocks are respectively subject to an intra or inter prediction for compensating a current macroblock by using information on adjacent pixels neighboring the current macroblock or a previous frame of the current macroblock, and then compressed through a transform of the difference between the image of the current macroblock and the image after the compensation with a subsequent quantization and an entropy encoding. In this process, since there are occasions of image loss during the quantization and the step of referencing the previous image or blocks neighboring the current image may have different images referenced by the respective blocks, a phenomenon of blocking artifact shows boundaries of blocks at each of the units of transform or motion compensation. As the intensity of the quantization gets stronger, such phenomenon becomes more prominent to significantly degrade the video quality.
Therefore, a block encoding needs to reduce the blocking artifact due to the motion compensation and transform by using a means called deblocking filter for smoothing the boundaries between blocks.
The deblocking filter used for H.264 video codec performs the filtering by deciding whether to filter at every boundary of the 4×4 block that is the minimum processing unit. That is, the filtering is not applied to an edge decided but the filtering is carried out upon identifying the blocking artifact not the edge. According to a method of filtering with respective to a macroblock, the deblocking filter is first taken horizontally across the vertical block boundaries as shown in FIG. 1, and then taken vertically across the horizontal block boundaries as shown in FIG. 2.
As illustrated, existing deblocking filters conduct filtering in vertical and horizontal directions only but refrain from the filtering when a block boundary is determined as an edge of the actual image. However, for a diagonal edge other than an edge in the vertical or horizontal direction, there is a problem that a blocking artifact within the diagonal edge at the block boundary cannot be removed.

Video encoding/decoding apparatus, de-blocking filter and filtering method based on intra-prediction directions for same, and recording media


System and methods are disclosed to qualify networks properties and that can be used for topology synthesis of networks, such as a network-on-chip (NoC). In accordance with various embodiments and different aspects of the invention, quality metric are generated, analyzed, and used to determine a quantitative quality set of values for a given generated solution for a network. The method disclosed allows the network designer or an automated network generation process to understand if the results produced are a good, an average or a bad solution. The advantage of the invention includes simplification of design process and the work of the designer by using quality metrics. Various quality metrics are generated using network definitions. These quality metrics provide quality evaluation and the quality assessment of the optimization process for a generated (optimized) network. The quality metrics include analyzing latency through a network and analyzing total wore length used by the network.

Multiprocessor systems have been implemented in systems-on-chips (SoCs) that communicate through network-on-chips (NoCs). The SoCs include instances of master (initiators) intellectual properties (IPs) and slave (targets) IPs. Transactions, in the form of packets, are sent from a master to one or more slaves using industry-standard protocols. The master, connected to the NoC, sends a request transaction to a slave, using an address to select the slave. The NoC decodes the address and transports the request from the master to the slave. The slave handles the transaction and sends a response transaction, which is transported back by the NoC to the master.
For a given set of performance requirements, such as connectivity and latency between source and destination, frequency of the various elements, maximum area available for the NoC logic, minimum throughput between sources and destinations, position on the floorplan of elements attached to the NoC, it is a complex task to create an optimal NoC that fulfills all the requirements with a minimum amount of logic and wires. This is typically the job of the chip architect or chip designer to create this optimal NoC, and this is a difficult and time-consuming task. In addition to this being a difficult task, the design of the NoC is revised every time one of the requirement changes, such as modifications of the chip floorplan or modification of the expected performance. As a result, this task needs to be redone frequently over the design time of the chip. This process is time consuming, which results in production delays.
As indicated, it is a complex task to create an optimal NoC that fulfills all the requirements in term of performance and a minimized the amount of logic and wires used. This is a difficult and time-consuming task. Also, the design of the NoC is revised every time one of the requirements changes. As a result, optimization of the NoC is redone frequently over the design time. Various processes are contemplated to automatically create a NoC, when given a set of constraints. Regardless of the process used to create automatically a NoC, the results produced by the automated process need to be assessed to determine the quality of the result or output. Therefore, what is needed is a system and method to analyze a NoC and produces quality metrics for a given generated solution for the NoC.

System and method for generation of quality metrics for optimization tasks in topology synthesis of a network


The inventive system comprises an autonomous robot device, a base station and a method operating the same. The autonomous robot device includes a sensor means, e.g. an optical sensor, and a propulsion means. The base station includes a cleaning means specifically adapted for cleaning the sensor means of the autonomous robot device. In a preferred embodiment the propulsion means of the autonomous robot device is configured to move the autonomous robot device in a manner suitable to generate a relative movement of the autonomous robot device with respect to the passive cleaning means arranged at the stationary base station to effect the cleaning of the sensor means of the autonomous robot device.

Field
The present invention relates to a system, a base station and a method for cleaning a sensor of an autonomous robot device like an autonomous garden device. In particular the present invention relates to a base station for an autonomous lawn mower and a system for cleaning an optical sensor mounted on the autonomous lawn mower. The present invention further relates to a base station for an autonomous robot device and a method for cleaning the sensor of the autonomous robot device.
Autonomous or robotic devices, e.g. autonomous lawn mowers, are an increasing market. In many approaches of autonomous lawn mowers the working area is delimited by an electric border wire generating an electromagnetic field. This electromagnetic field is used by the autonomous device to identify the assigned working area, and to find a docking station or base station for recharging its energy storage. For avoiding static or dynamic obstacles that are not indicated by the border wire some commercially available autonomous mowers use bump sensors and/or sonar sensors.
Description of the Related Art
The term "autonomous device" is well known to the man skilled in the art as referring to an unmanned device which has a drive means or propulsion means in order to move the autonomous device ("self-propelled device"), an onboard energy reservoir to power the propulsion means, one or more sensors and a control means functionally connected to the sensor(s) and the drive means. The autonomous device navigates in a free manner without human support based on sensor data acquired by the sensor(s) and processed in the control means in order to generate control signals for the propulsion means.
WO 2005/074362 A2 discloses a docking station and an autonomous robot for docking therein, the docking station providing capabilities of recharging the autonomous robot's battery and exchanging signals with the autonomously operating robot.
A future path for improving the functionality of autonomously operating robot devices particularly in the outdoor environment includes furnishing more sensors and/or sensors with improved characteristics or altogether new capabilities such as optical sensors to the autonomous device. However the quality of signals generated by these new sensors and in particular by optical sensors, e.g. cameras, depend on clean optics and lenses for acquiring the visual information in the demanding outdoor environment. An outdoor environment such as a garden under varying weather conditions and performing tasks such as cutting grass in case of a autonomous lawn mower further increases the exposure of the sensor to dirt, sand, parts of plants, water, etc. Hence regular maintenance of the sensors is of high importance to achieve a high mean time between failure of the autonomous device due to sensor failure.
In outdoor environment exists a long standing need for providing surveillance cameras with a minimum at regular maintenance to be necessary for a guarantying a high level of availability for the surveillance camera sensor even when mounting the surveillance camera under a protective camera dome. Patent document U.S. Pat. No. 6,527,000 B1 provides a surveillance camera dome with a device mounted wiper and washer assembly and for cleaning the surveillance dome surface in order to provide the camera with an unobstructed view over the full viewing area without requiring a regular operator maintenance. The features disclosed in the document U.S. Pat. No. 6,527,000 B1 for cleaning the sensor equipment at short intervals would seem advantageous to the man skilled in the art.
However the aim of providing the sensor of an autonomous robot with a washer and wiper assembly introduces an additional motor or actuator and also a tank for cleaning agents to be refilled at regular intervals. Therefore the complexity of the autonomous robot device and the complexity of its operation is further increased.
Hence the technical problem of providing an autonomous robot device with a robust, capable and cost effective sensor cleaning mechanism arises.

Sensor cleaning system for an autonomous robot device, base station and corresponding method


An information processing apparatus includes an interface unit, a detection unit, an unmount unit, a display unit, and a control unit. The interface unit connects a reader/writer device, which is capable of receiving a memory storage medium. The detection unit detects a connection and a disconnection between the interface unit and the reader/writer device. The unmount unit sets the memory storage medium to an unmounted state. The a display unit display information about a detection result by the detection unit. The control unit controls, in response to the detection unit detecting that the reader/writer device is temporary disconnected from the interface unit, the display unit not to display information about the temporary disconnection of the reader/writer device from the interface unit.

1. Field of the Invention
The present invention relates to an information processing apparatus that is connectable to an external device (peripheral device) via an interface.
2. Related Background Art
Conventionally, a Universal Serial Bus (USB) interface has been used to establish a connection between a host apparatus and an external device. When a host apparatus is connected to an external device, the host apparatus detects the connection of the external device to a USB interface, through a device driver for example, and performs a process to make the external device accessible. When the host apparatus receives an instruction to disconnect the external device from an operator, the host apparatus performs processing for shifting a state that the external device can be disconnected therefrom. If the external device is physically disconnected from the host apparatus, the host apparatus detects the disconnection of the external device from the USB interface using a device driver for example, and performs processing for shifting a state that the external device is disconnected therefrom.
In such a system, sometimes an unintended event, for example static electricity is applied to the external device, may accidentally happen and make the electrical connection between the host apparatus and the external device temporarily disconnected. In such a case, a turn-off and restart of the host computer is necessary and a recovery may take long time. To address this problem, Japanese Patent Application Laid-Open No. 2003-131956 discusses a technique in which a circuit of a general interface for transmission and reception of data between a host apparatus and an external device is restarted. Japanese Patent Application Laid-Open No. 2008-27379 discusses a technique for restarting a device control module in a host apparatus.
In the conventional techniques, when an information processing apparatus such as a host apparatus is electrically disconnected temporarily from an external device due to static electricity for example, a device control module is restarted to reset the external device to a connection state. Such approach to recover the connection, however, does not store the previous connection state of the external device before the disconnection. Thus, even when the device control module is restarted to connect the host apparatus to the external device again, the restored connection state is not always the same state before the disconnection. In this case, when the host apparatus attempts to access the external device based on the connection state before disconnection, the host apparatus may not be able to access the external device due to a mismatch between the connection states before and after the disconnection.

Information processing apparatus, and method for controlling the same


A multilayer belt structure that can be used for creping or structuring a cellulosic web in a tissue making process. The multilayer belt structure allows for the formation of various shaped and sized openings in the top surface of the belt, while still providing a structure having the strength, durability, and flexibility required for tissue making processes.

Processes for making tissue products, such as tissue and towel, are well known. Soft, absorbent disposable tissue products, such as facial tissue, bath tissue and tissue toweling, are a pervasive feature of contemporary life in modem industrialized societies. While there are numerous methods for manufacturing such products, in general terms, their manufacture begins with the formation of a cellulosic fibrous web in the forming section of a tissue making machine. The cellulosic fibrous web is formed by depositing fibrous slurry, that is, an aqueous dispersion of cellulosic fibers, onto a moving forming fabric in the forming section of a tissue making machine. A large amount of water is drained from the slurry through the forming fabric, leaving the cellulosic fibrous web on the surface of the forming fabric. Further processing and drying of the cellulosic fibrous web generally proceeds using at least one of two well-known methods.
These methods are commonly referred to as wet-pressing and drying. In wet pressing, the newly formed cellulosic fibrous web is transferred to a press fabric and proceeds from the forming section to a press section that includes at least one press nip. The cellulosic fibrous web passes through the press nip(s) supported by the press fabric, or, as is often the case, between two such press fabrics. In the press nip(s), the cellulosic fibrous web is subjected to compressive forces which squeeze water therefrom. The water is accepted by the press fabric or fabrics and, ideally, does not return to the fibrous web or tissue.
After pressing, the tissue is transferred, by way of, for example, a press fabric, to a rotating Yankee dryer cylinder that is heated, thereby causing the tissue to substantially dry on the cylinder surface. The moisture within the web as it is laid on the Yankee dryer cylinder surface causes the web to adhere to the surface, and, in the production of tissue and towel type products, the web is typically creped from the dryer surface with a creping blade. The creped web can be further processed by, for example, passing through a calender and wound up prior to further converting operations. The action of the creping blade on the tissue is known to cause a portion of the interfiber bonds within the tissue to be broken up by the mechanical smashing action of the blade against the web as it is being driven into the blade. However, fairly strong interfiber bonds are formed between the cellulosic fibers during the drying of the moisture from the web. The strength of these bonds is such that, even after conventional creping, the web retains a perceived feeling of hardness, a fairly high density, and low bulk and water absorbency. In order to reduce the strength of the interfiber bonds that are formed by the wet-pressing method, Through Air Drying ("TAD") can be used. In the TAD process, the newly formed cellulosic fibrous web is transferred to a TAD fabric by means of an air flow, brought about by vacuum or suction, which deflects the web and forces it to conform, at least in part, to the topography of the TAD fabric. Downstream from the transfer point, the web, carried on the TAD fabric, passes through and around the Through-Air-Dryer, where a flow of heated air, directed against the web and through the TAD fabric, dries the web to a desired degree. Finally, downstream from the Through-Air-Dryer, the web may be transferred to the surface of a Yankee dryer for further and complete drying. The fully dried web is then removed from the surface of the Yankee dryer with a doctor blade, which foreshortens or crepes the web thereby further increasing its bulk. The foreshortened web is then wound onto rolls for subsequent processing, including packaging into a form suitable for shipment to and purchase by consumers.
As noted above, there are multiple methods for manufacturing bulk tissue products, and the foregoing description should be understood to be an outline of the general steps shared by some of the methods. Further, there are processes that are alternatives to the Through-Air-Drying process that attempt to achieve "TAD-like" tissue or towel product properties without the TAD units and high energy costs associated with the TAD process.
The properties of bulk, absorbency, strength, softness, and aesthetic appearance are important for many products when used for their intended purpose, particularly when the fibrous cellulosic products are facial or toilet tissue or towels. To produce a tissue product having these characteristics on a tissue making machine, a woven fabric will be used that is often constructed such that the sheet contact surface exhibits topographical variations. These topographical variations are often measured as plane differences between woven yarn strands in the surface of the fabric. For example, a plane difference is typically measured as the difference in height between a raised weft or warp yam strand or as the difference in height between machine-direction (MD) knuckles and cross-machine direction (CD) knuckles in the plane of the fabric's surface
In some tissue making processes as mentioned above, an aqueous nascent web is initially formed in the forming section from a cellulose content furnish, using one or more forming fabrics. Transferring the formed and partly dewatered web to the press section, comprising one or more press nips and one or more press fabrics, the web is further dewatered by an applied compressive force in the nip. In some tissue making machines, after this press dewatering stage, a shape or three dimensional texture is imparted to the web, with the web thereby being referred to as a structured sheet. One manner of imparting a shape to the web involves the use of a creping operation while the web is still in a semi-solid, moldable state. A creping operation uses a creping structure such as a belt or a structuring fabric, and the creping operation occurs under pressure in a creping nip, with the web being forced into openings in the creping structure in the nip. Subsequent to the creping operation, a vacuum may also be used to further draw the web into the openings in the creping structure. After the shaping operation(s) are complete, the web is dried to substantially remove any desired remaining water using well-known equipment, for example, a Yankee dryer.
There are different configurations of structuring fabrics and belts known in the art. Specific examples of belts and structuring fabrics that can be used for creping in a tissue making process can be seen in U.S. Pat. Nos. 7,815,768 and 8,454,800 which are incorporated herein by reference in their entirety.
Structuring fabrics or belts have many properties that make them conducive for use in a creping operation. In particular, woven structuring fabrics made from polymeric materials, such as polyethylene terephthalate (PET), are strong, dimensionally stable, and have a three dimensional texture due to the weave pattern and the spaces between the yarns that make up the woven structure. Fabrics, therefore, can provide both a strong and flexible creping structure that can withstand the stresses and forces during use on the tissue making machine The openings in the structuring fabric, into which the web is drawn during shaping, can be formed as spaces between the woven yarns. More specifically, the openings can be formed in a three dimensional manner as there are "knuckles" or crossovers of the woven yarns in a specific desired pattern in both the machine direction (MD) and cross machine direction (CD). As such, there is an inherently limited variety of openings that can be constructed for a structuring fabric. Further, the very nature of a fabric being a woven structure made up of yarns effectively limits the maximum size and possible shapes of the openings that can be formed. Thus, while woven structuring fabrics are structurally well suited for creping in tissue making processes in terms of strength, durability and flexibility, there are limitations on the types of shaping to the tissue making web that can be achieved when using woven structuring fabrics. As a result, there are limits to simultaneously achieving higher caliper and higher softness of a tissue or towel product made using a woven fabric for the creping operation.
As an alternative to a woven structuring fabric, an extruded polymeric belt structure can be used as the web-shaping surface in a creping operation. Openings (or holes or voids) of different sizes and different shapes can be formed in these extruded polymeric structures, for example, by laser drilling, mechanical punching, embossing, molding, or any other means suitable for the purpose.
The removal of material from the extruded polymeric belt structure in forming the openings, however, has the effect of reducing the strength and resistance to both MD stretch and creep, as well as durability of the belt. Thus, there is a practical limit on the size and/or density of the openings that may be formed in an extruded polymeric belt while still having the belt be viable for a tissue making creping process.
One requirement of a creping belt or fabric is to be configured to substantially prevent cellulose fibers in the web of the tissue or towel product from passing through the openings of the aping belt in the creping nip. As a result, sheet properties such as caliper, strength and appearance will be less than optimum.

Multilayer belt for creping and structuring in a tissue making process