A welded sleeve applicator (10) and method for forming an identification sleeve (34) around an elongate object (16) is disclosed. A leading end portion (22) of a continuous strip (24) of identification indicia-bearing, ultrasonically weldable material is fed by a printer (18) onto a base (12), passing under an elongate object that is received on the base. The leading end portion of the material strip overlies a flexible wrapping strap (26). A pivot arm (28) wraps the strap and the leading end portion of the material strip around the elongate object. The wrapped leading end portion of the material strip is retained in place over an adjacent second portion (100) of the material strip by a vacuum drawn through a guide (30). The pivot arm and wrapping strap are removed, and an ultrasonic welding horn (32) is lowered to weld the leading end portion and the second portion of the material strip together, forming an indicia-bearing, tubular sleeve.

Many manufacturing processes require placement of identification tags on thin, elongate objects, such as wires, hoses and pipes. In complex communication and electric power distribution systems, individual wires within wiring harnesses must be correctly identified for proper connection of subsystems. Similarly, in hydraulic and pneumatic systems, hydraulic and pneumatic hoses and tubes also must be identified for correct coupling. Tags must be applied in a manner to identify individual objects with certainty, while not harming the object nor interfering with interconnection or function of the objects.
Conventional techniques for identifying individual conductors within wiring harnesses, such as those used in aircraft electrical systems, involve the placement of heat shrinkable, tubular identification sleeves over individual conductors, conductor-bundles, or cables. The tubular sleeving, commonly referred to as heat shrink tubing, is made of polymeric material that has been previously expanded and that, when heated, shrinks down to its original dimensions to form a tight fit around the object over which it has been placed. A length of conventional heat-shrink tubing is first marked by embossing or printing with identification indicia, such as numerals or letters. The marked tubing is then cut into individual pieces of a desired length, which are then individually threaded onto the object to be identified. Individual handling, marking and application of cut tubing is cumbersome and time-consuming.
An alternative type of conventional sleeve has been developed that is somewhat easier to mark with identification indicia. Two flat sheets of heat shrinkable material are periodically welded together along transverse lines to form a welded sheet of flat sleeves. The welded sheet can then be printed upon to place indicia on each sleeve. Individual sleeves are cut from the sheet prior to placement on wires or other objects to be identified.
Both heat-shrink tubing and flat welded sheets have the disadvantage of needing to be preprinted in advance with the identification indicia expected to be required for a particular manufacturing process. The individual operator then must select the correct preprinted sleeve corresponding to a particular wire to be identified. The requirement of preprinting and preparing individual sleeves is costly and time-consuming, and does not allow production flexibility with regard to changing identification requirements during a manufacturing run. Existing methods also do not enable printing on both sides of a piece of sleeving, as is sometimes desired, without turning over the sleeving.
An improved method for identifying objects is disclosed by U.S. Pat. No. 4,770,729, entitled "Method of Making a Welded Sleeve Identification" and assigned to the assignee of the current application. The method involves the printing of indicia on the leading end of a continuous strip of heat-shrinkable material, cutting indicia bearing pieces from the strip, and wrapping the pieces around an object to be identified. Each cut piece is gripped by a multiple joint arm and then moved to a position over top of the object to be identified, whereupon it is wrapped around the wire in a generally U-shaped configuration. The outwardly extending ends of the U-shaped pieces are then ultrasonically welded together adjacent the object to form a welded sleeve that can later be heat-shrunk into place. While this method represents a significant improvement over other prior art methods, the method has a disadvantage associated with handling the individual cut pieces of material and potential problems associated with mispositioning cut pieces when they are wrapped around the object to be identified.

Method and apparatus for forming a welded identification sleeve


Methods for drying and cleaning objects that may have been wetted or contaminated in a manufacturing process. The objects are submerged in a rinse liquid in an enclosed chamber, and aerosol particles from a selected liquid are introduced into the chamber above the rinse liquid surface, forming a thin film on this surface. As the rinse liquid is slowly drained, some aerosol particles settle onto the exposed surfaces of the objects, and displace and remove rinse liquid residues from the exposed surfaces, possibly by a "chemical squeegeeing" effect. Surface contarminants are also removed by this process, which may be carried out at or near room temperature. Chamber pressure is maintained at or near the external environment pressure as the rinse liquid is drained from the chamber.

Objects that are being manufactured using processes involving application of liquids and other fluids often require that the parts be thoroughly dried before the manufacturing process can continue. For example, in fabrication of integrated circuits, doping, photomasking, etching and passivation processes often require application of particular liquids at one stage and removal of liquid residues before the next stage proceeds. Drying and removal of these liquid residues must be complete, but the drying process should, ideally, occur in a relatively short time interval and with expenditure of a minimum of energy and chemicals to implement the drying process.
Several workers have disclosed methods for drying parts, including integrated circuits, by use of heated or superheated gases. McConnell et al, in U.S. Pat. No. 4,577,650, No. 4,633,983, No. 4,738,272, No. 4,778,532, No. 4,856,844, No. 4,899,767, No. 4,911,761, No. 4,917,123 and No. 4,984,597, disclose methods of drying semiconductor wafers by flowing a heated vapor or fluid past the wafers to be dried in a vessel, as part of a wafer processing sequence. The preferred drying vapor is superheated isopropanol, which forms a minimum boiling azeotrope with water and is believed to displace water from the wafer surfaces, and the vapor flows into the vessel at one end and simultaneously flows out of the vessel at another end.
In U.S. Pat. No. 5,383,484, Thomas et al disclose use of a plurality of megasonic beam transducers, located at staggered positions, for cleaning wafers. Each transducer emits a vibratory megasonic beam with an unspecified (very high) frequency in a fixed direction, and the transducer locations are chosen so that the collection of beams irradiate, and thereby clean, all wafer surfaces in a chamber, no matter how the wafers are arranged.
Use of ultrasonic transducers in a chemical cleaning bath to cooperatively remove contaminants and unwanted material layers from semiconductor wafers, medical instruments and other objects of interest is disclosed by Erickson et al in U.S. Pat. No. 5,178,173, by Watanabe et al in U.S. Pat. No. 5,203,798, by Tamaki et al in U.S. Pat. No. 5,227,001, by Evans et al in U.S. Pat. No. 5,248,456, by Smith et al in U.S. Pat. No. 5,337,446, by Koretsky et al in U.S. Pat. No. 5,368,054, by Steinhauser et al in U.S. Pat. No. 5,380,369, by Shibano in U.S. Pat. No. 5,447,171, by Awad in U.S. Pat. No. 5,464,477, by Kato in U.S. Pat. No. 5,467,791, by Thjietje in U.S. Pat. No. 5,468,302 and by Campbell in U.S. Pat. No. 5,472,005.
Use of ultrasonic transducers to coat, spray, deposit or otherwise apply a desired material to an object surface is disclosed by Bachmann in U.S. Pat. No. 5,387,444, by Erickson et al in U.S. Pat. No. 5,409,163, and by Versteeg et al in U.S. Pat. No. 5,451,260. An ultrasonic fogging device is disclosed by Munk in U.S. Pat. No. 5,454,518.
These approaches heated or superheated gases or direct beam irradiation to dry an object surface; or they use cooperative action by an ultrasonic beam and an active chemical bath to remove contaminants from, or to apply a desired material to, an object surface. These approaches are complex, usually require operation at high temperatures, often require processing times of several minutes, and often require use of specially resistant chamber walls for the processing chamber.
What is needed is a method and associated apparatus for drying and cleaning objects in a manufacturing process that works well at room temperature and is simple, that is demonstrably complete, with no significant residues, that can be accomplished in times as short as one minute, that can be performed in a chamber with chamber walls made of almost any material, and that requires use of only a very small amount of a drying agent, with minimal expenditure of energy, particularly thermal energy. Preferably, the process should be performable over a wide range of temperatures, and should be easily scalable to any size surface.

Methods for drying and cleaning objects using aerosols


An information processing method to be executed by a processor, the processing method includes setting an area target amount of reduction in power consumption of a target area; acquiring a predicted value and a measured value of outdoor temperature at each of a plurality of subareas included in the target area; calculating, for each of the plurality of subareas, a prediction error of outdoor temperature by calculating a difference between the predicted value and the measured value; calculating, for each of the plurality of subareas, a utilization rate indicating a rate of assignment of the area target amount of reduction in power consumption by solving an objective function generated based on the area target amount of reduction and a variance of the prediction error of outdoor temperature; and determining, for each of the plurality of subareas, a subarea target amount of reduction in power consumption based on the utilization rate.

In recent years, an intermediate provider that is called a demand response (DR) aggregator is known, which executes control (demand response (DR)) of power to be consumed by users instead of an electric power provider in response to a request to reduce power to be consumed by the users from the electric power provider such as an electric power company or a power product supplier (PPS). As a method for executing the DR by the DR aggregator, there is a method called direct load control (DLC) that is executed to directly control amounts of power to be consumed by apparatuses used by users, for example. The apparatuses to be subjected to the DLC are air-conditioning apparatuses, lighting apparatuses, refrigerating facilities, freezing facilities, in-house generators, and the like, for example. If the DLC is executed on an air-conditioning apparatus in summer, The DR aggregator may increase a set temperature of the air-conditioning apparatus and thereby control the amount of power to be consumed.
As related art, Japanese Laid-open Patent Publications Nos. 2003-87969, 2007-129873, and 2012-23816 have been disclosed, for example.
The DR aggregator sets a target amount of a reduction in power to be consumed in response to a request from an electric power provider before (for example, a day before the execution of the DR) executing the DR. Then, the DR aggregator preferably develops a program for executing the DLC in order to achieve the target amount at a high rate.

Information processing method, program development device, recording medium, and method


A rotary cutter including a handle, a cylindrical head formed on one end of the handle and having a planar surface on each side, the handle and head having an internal cavity, a unitary actuating member mounted in the cavity in the handle and head, a circular blade supported by the actuating member for movement between a storage position and an operating position with respect to one of the planar surfaces, the actuating member including a spring for biasing the blade to the storage position, and a resilient latch for locking the actuating member in the operative position.

Hand held rotary cutters of the type contemplated herein are shown in U.S. Pat. No. 5,101,564, entitled "Hand Held Cutter Having A Rotatable Circular Blade And Safety Guard," issued on Apr. 7, 1992, to Craig H. Melter, and U.S. patent application Ser. No. 07/944,870, entitled "Rotary Cutting Blade Assembly For A Hand Held Cutter," filed on Sep. 14, 1992. Each of these prior art references describe rotary cutters wherein the blade is moved along an arcuate path relative to the handle to selectively expose and retract the cutting perimeter of the blade. A pivotable member is mounted within the head of the handle to support the blade and is biased to a retracted position with respect to the head of the handle. The blade is advanced to an operative position by an actuating lever pivotably mounted in the head. The actuating lever is biased to a retracted position by elastic bands located within the handle.

Rotary blade actuator for a hand held cutter


A front suspension unit for the independent suspension of the front wheels of a motor powered off road four wheel vehicle comprising a pair of suspension units with their outer casings mounted together and the inner members carrying laterally extending arms with their free ends constituted for attachment to front wheel mounting assemblies and such units in combination with a steering assembly having a column to be supported at one end from the vehicle chassis and carrying a steering wheel and axle on the other end, the axle having a chain and sprocket mounted thereon with the ends of the chain attached to a plate rotatably mounted on the column and carrying link arms to be attached one to each of the front wheel mounting assemblies.

Small vehicles of the kind referred to are becoming more and more popular for recreational and other general purpose off-road usage. In general the vehicles lack adequate suspension units to enable them to be used at speed unless they are driven on flat and smooth prepared tracks. This is a severe limitation and removes much of the pleasure to which they could otherwise be put.


An extruded and stamped personal washing bar comprising an artisan crafted appearance having top and bottom stamped faces bounded by a parting line or edge band and a horizontal plane intersecting the parting line or edge band, said bar further comprising an outer surfactant phase and a substantially contiguous inner vein comprising a thermoplastic mass, wherein said inner vein is located between the top and bottom stamped faces of the bar and wherein a projection of the inner vein onto the horizontal plane intersecting the parting line or edge band has a maximum width that is at least 20% of a maximum width of the bar in said horizontal plane.

With the resurgence in the specialty soap market, consumers are being offered personal washing bars that have a much more hand crafted "one-of a kind" appearance—so called artisan soaps. Technically such bars have several characteristics that contribute to their distinctive appearance: i) sharpness of the boundary between the phases; ii) easily recognizable difference in optical texture and/or pattern that goes beyond color; and iii) a certain degree of bar to bar non-uniformity. Differences in optical texture and pattern are especially important to convey a collection of sensory expectations associated with bar.
To achieve a highly distinctive appearances, artisan soaps have been predominantly made by cast melt processes—either single casting or sequential multiple casts. For example, U.S. Pat. No. US 2003/0171232—2003 to Freeman et al discloses a decorative soap that contains soap inclusions that are coated with a glitter agent (metallic pigment) in a powder coater. The coating makes the soap inclusions resemble a mineral.
Although melt-cast processes can yield bars with highly controlled patterns, they are generally slow and labor intensive. Consequently, multiphase artisan soaps are relatively expensive and tend to be confined to upscale specialty shops and outlets. Furthermore, melt cast soaps are known to have high wear rates and mushing characteristics that make them less preferred for everyday use.
The objective of the present invention is a multiphase bar that has an unusual artisan-crafted appearance yet can be produced by an efficient high speed extrusion process and conventional stamping.
A further objective is an artisan bar that have wear rate and mushing properties characteristic of milled soap and is thus economical for everyday use.
U.S. Pat. No. 6,730,642 to Aronson et al describes an extruded soap in which is dispersed a second phase that is added as solid pieces prior to the final compaction step in billet formation. By controlling the hardness ratio of the two solids, deformation of dispersed phase during extrusion can be minimized thus producing bars with visually distinctive chunks or bits dispersed throughout.
The present work targets an extruded multiphase bar having a very different structure in which the inclusion is in the form of a veins or ribbon located in the interior of the bar. This structure produces an appearance that is reminiscent of a translucent natural mineral such as for example, quartz or opal in which inclusions of a different composition are visible or become visible veins within the mineral. Technically, this appearance arises from the inclusion having a substantial surface area being approximately spatially confined within to a relatively thin volume slice in the material, i.e. ribbon-like structure. The inclusions are also optically non uniform. When the mineral is translucent or transparent the vein or ribbon can be perceived deep within the material while if the mineral is opaque the vein is only visible when present very close to the surface or when the mineral is fractured or ground to expose the vein.
Various attempts to approximate a veined appearance in bars have been described in the soap art under the heading of variegated, marbled, striated, and striped soaps. Prior art has mainly focused on routes to reproducibly achieve spatial variation in dye or pigment concentration as the primary means of generating bars that appear as comprising multiple phases.
One commonly used technique to make striated soaps is to combination of different color noodles to form a mixture in for example the vacuum chamber of an extruder. This mixture is then extruded to form a billet which is then stamped into a bar. This method is disclosed in the following parents:
U.S. Pat. No. 3,673,294 to Matthaei et al, teaches a process to form multicolored bars by extruding a mixture of two noodles which are required to have the same viscosity and essentially the same hardness (penetration value).
U.S. Pat. No. 3,940,220 to D'Arcangeli teaches the extrusion of a mixture of two noodles in which it is required that the discontinuous phase be softer [lower penetration value] than the main soap.
U.S. Pat. No. 3,993,722, to Borcher et al and U.S. Pat. No. 4,092,388 to Lewis teaches processes of combining different colored noodles to formed marbled soap. The two noodles have essentially the same composition apart from colorant and the two different color noodles have essentially the same temperature at the time of extrusion.
U.S. Pat. No. 4,310,479 to Ooms et al teaches a process for combining a minor amount of opaque noodles with transparent noodles to form a transparent marbled bar. The noodles should differ in water content by no more than 3% and are at the same temperature during extrusion.
U.S. Pat. No. 6,390,797 to Meyers teaches a process for making marbleized or speckled soap by addition of a second stream of colored soap pellets into the inner of the final stage plodder at a specific point.
A second common method of producing striated soaps is the injection of a dye solution during extrusion. Examples of patents disclosing this type of process include:
U.S. Pat. No. 4,474,545 to Mazzoni teaches radial dye injection at nose cone entry and employs a rotor within nose cone to produce wavy stripes.
U.S. Pat. No. 3,676,538 Patterson teaches the injection of a saponaceous dye solution through screw of plodder at the pressure plate before nosecone to make marbled soaps.
U.S. Pat. No. 3,663,671 to Meye et al teaches injection of dye solution into at least two inlets in the jacket of the plodder of an extruder in set locations.
U.S. Pat. No. 3,832,431 to Matthaei discloses injection of dye in given rates, at specific point through the wall in the barrel of the final stage extruder to make marbled bars.
U.S. Pat. No. 4,304,745 to Alderson et al discloses soap extruded via single screw through a perforated plate having large holes at the periphery and small holes in the center. Dye is injected in the middle of the plate to form bars with large colored striped at surface.
U.S. Pat. No. 4,720,365 to Shonig et al discloses the addition of liquid dye after pressured exit of final extruder via a pressure plate which has multiple holes to form finely striated bars.
In both of the broad methods described above (extrusion of a combination of colored noodles and dye injection) the multicolored soap mass undergoes considerable extensional and/or shear flow during billet formation. Consequently, the numerous multiple striations so produced are randomly located throughout the bar and are generally elongate structures that individually have relatively small width in comparison with the overall width of the bar.
Coextrusion has also been used to make striped soaps. For example:
U.S. Pat. No. 3,884,605 to Grelon teaches an apparatus for making striated soap by coextrusion where it is desirable that the two soaps have identical material properties, e.g., hardness, apart from color.
U.S. Pat. No. 6,383,999 to Coyle et al teaches a coextruded multiphase bar in which the phases differ in the level of emollient but must have similar flow properties under extrusion process conditions.
WO 01/91990 to Trinque discloses a "soap striater" comprising a primary and perpendicular plodder feeding a tube partitioned chamber exiting a perforated pressure plate into a nose cone. Some of the apertures may be blocked to get different patterns
U.S. Pat. No. 3,294,692 to Kelly et al discloses a striped bar made by injecting different colored masses into "grooved billet" through multiple extruders feeding a single chamber.
The coextruded bars described above have a pattern of distinctive multiple stripes which are uniformly distributed throughout the bar. Each stripe is visually uniform and occupies a relatively small cross sectional area relative to the overall area of the bar.
In contrast, the bars of the present invention have one or more inner veins. By inner vein we mean a ribbon-like, preferably non-uniform, structure that does not touch the surface of the bar when the bar is first produced, i.e., there is a layer of extruded soap between the vein and the surface of the bar. Furthermore, each vein is located approximately within a volumetric slice orientated in a horizontal plane between the top and bottom surfaces of the bar. By the term horizontal plane is meant a plane that is parallel to either a plane that is tangential to the bottom surface of the bar or to a plane that is tangential to the top surface of the bar. For most bars of commercial interest, these top and bottom tangential planes are essentially parallel.
Another distinguishing feature of the bars of the current invention is the expanse of the inner vein. In contrast to previous multi-phase extruded bars, the inner vein forms a contiguous mass (connected) that occupies a substantial portion of the area of the overall bar within the volumetric slice where it is predominantly located.
For example, if the outer extruded phase was transparent and the inner vein was opaque, then an individual vein when viewed through the bar in a direction perpendicular to the top face would be observed to occupy an area that is at least about 15% of the total cross sectional area of the bar (considered a substantial portion of the area), preferably at least 20%, more preferably at least 30% and most preferably greater than 50% of the total cross sectional area of the bar.
An alternative description of substantial expanse of the vein can be given in terms of a characteristic dimensions relative to the bar. One such characteristic dimension is the maximum width of the vein within a specified plane of the bar relative to the maximum width of the overall bar. Using again the above example of a transparent outer phase and an opaque vein, then the inner vein when viewed through the bar in a direction perpendicular to the top face would be observed to have a maximum width that is at least about 15% of the maximum width of the bar (considered a substantial fraction of the overall width of the bar), preferably at least 20%, preferably at least 25%, more preferably at least about 30% and most preferably greater than 50% of the maximum width of the bar. The term width is used here in its normal sense to designate the smaller orthogonal dimension of the bar in a plane perpendicular to the top face of the bar.
By the term "maximum width of the inner vein" is meant the width of the vein at its widest point. By the term "maximum width of the bar" is meant the width of the bar at its widest point.
Bars having these and additional characteristics and properties can be made by following the teachings of the present invention.


An image forming apparatus includes an image forming unit, a feeder unit, and a frame unit. The frame unit includes a pair of plate-like metal frames, each plate-like metal frame having an inner surface extending in a parallel direction to a sheet feeding path and in a perpendicular direction of a surface of a recording sheet, and a plurality of connecting frames connecting and holding the metal frames to be apart from each other. The image forming unit is arranged in space defined by the connecting frames and held by the metal frames to be substantially fitted in between the metal frames. The feeder unit is attached to an end of each of the metal frames by an attachment system provided on each widthwise side of the feeder unit. The attachment system fixes the feeder unit along a direction in parallel with the inner surfaces of the metal frames.

1. Technical Field
An aspect of the present invention relates to an image forming apparatus having an image forming unit to form an image on a recording medium, a feeder unit to feed the recording medium to the image forming unit, and frames to hold the image forming unit and the feeder unit.
2. Related Art
An image forming apparatus having an image forming unit to form an image on a recording medium in, for example, an electrophotographic method has been known. The image forming apparatus may be equipped with a pair of frames to hold the image forming unit, which are arranged on each side with respect to a feeding direction.
When the recording medium is fed in a feeding path to the image forming unit by a feeder unit having a feeding component such as a feed roller, it is required that the feeder unit is in a specific position with respect to the image forming unit. In an image forming apparatus disclosed in Japanese Patent Provisional Publication No. 2004-154974, for example, the feeder unit is attached to the image forming apparatus with a pair of frames, which are angled substantially orthogonally, so that the feeder unit is settled in a correct position defined by the orthogonal surfaces of the frames.


Exemplary embodiments provide coating compositions having pseudo-fluorine surface and methods for processing and using the coating compositions. The coating composition can include, for example, a plurality of fluorine-containing resin fillers and a plurality of nanotubes (e.g., carbon nanotubes (CNTs)) dispersed in a polymer matrix that contains, e.g., one or more cross-linked polymers. The fluorine-containing resin fillers can provide a pseudo-fluorine surface for a low surface energy of the coating composition. The nanotubes can be dispersed in the polymer matrix to provide an improved mechanical robustness of the coating composition. The coating composition can be coated on a member surface, wherein the coated member can be, for example, a fuser member, a fixing member, a pressure roller, or a release agent donor member, used in an electrostatographic printing device or process.

In current electrostatographic processes, two major types of fuser topcoat materials, e.g., fluoroelastomers and fluoroplastics, are used for the fusing technologies. For example, Viton fluoroelastomers provide good mechanical flexibility with an ability to absorb shock energy and also provide high speed with high print quality, although Viton fusers require a release agent to prevent an offset caused by the low fluorine content nature of the Viton fluoroelastomer. Such use of a release agent, e.g., silicone oil, increases the cost of RAM systems and causes end-use problems because silicone oil often remains on the prints. Oil-less fusing has therefore become more attractive.
Teflon fluoroplastics have high fluorine content and are widely used for oil-less fusing. For example, a fuser including a Teflon topcoat on a silicone elastomer layer may include a Teflon PFA surface that enables oil-less fusing and a conformable silicone layer that enables rough paper fix, low mottle and good uniformity Compared with Viton fluoroelastomers, however, Teflon PFA is easily damaged. In addition, fabrication of PFA topcoat requires harsh processing conditions such as high baking temperatures (e.g., over 350° C.), which can degrade the underlying silicone rubber layer.
Thus, there is a need to overcome these and other problems of the prior art and to provide coating compositions suitable and methods for processing and using the coating compositions.

Nanotube reinforced fluorine-containing composites


An optical encoder includes an optical encoder pattern of alternating light elements and dark elements, and an optical unit, including an optical emitter providing light to the encoder pattern, and an optical sensor including a photo-detector receiving the light from the optical encoder pattern and in response thereto outputting a sinusoidal signal indicating relative movement between the optical sensor and the encoder pattern. In one embodiment, the photo-detector has a diamond shape, a modified-diamond shape, or an hourglass shape. In another embodiment, at least one of the light elements and the dark elements of the optical encoder pattern has a diamond shape, a modified-diamond shape, or an hourglass shape.

Optical encoders are used in a wide variety of contexts to determine movement and/or a position of an object with respect to some reference. Optical encoding is often used in mechanical systems as an inexpensive and reliable way to measure and track motion among moving components. For instance, printers, scanners, photocopiers, fax machines, plotters, and other imaging systems often use optical encoding to track the movement of an image media, such as paper, as an image is printed on the media or an image is scanned from the media.
One common technique for optical encoding uses an optical sensor and an optical encoder pattern (or encoding media). The optical sensor focuses on a surface of the optical encoder pattern. As the sensor moves with respect to the optical encoder pattern (or encoding media), or the encoder pattern moves with respect to the optical sensor, the optical sensor reads a pattern of light either transmitted through, or reflected by, the optical encoder pattern to detect the motion.
A typical optical encoder pattern is an alternating series of light and dark elements. As the encoder and sensor move relative to the one another, transitions from one element to the next in the pattern are optically detected. For instance, an encoder pattern could be an alternating pattern of holes, or optically transmissive windows, in an opaque material. In that case, an optical sensor can detect transitions from darkness to light passing through the holes or windows.
FIG. 1 illustrates a basic optical encoder 100 comprising an optical unit 103 including an optical emitter 101 and an optical sensor 102, and a light controlling member (optical encoder pattern) 105 disposed between the optical emitter 101 and the optical sensor 102. Optical emitter 101 is a light source comprising, for example, one or more light emitting diodes. In general, optical sensor 102 comprises one or more photo-detectors, for example, photodiodes or charge coupled devices (CCDs). Optical unit 103 and optical encoder pattern 105 can move relative to each other in a linear fashion longitudinally of optical encoder pattern 105.
In one common application, optical unit 103 is mounted on the printing head of a printer, optical encoder pattern 105 is fixed to a case of the printer, and optical unit 103 moves along the length of encoder pattern 105 when the printing head moves. As optical unit 103 moves along the length of optical encoder pattern 105, light from optical emitter 101 passing through (or reflecting from) optical encoder pattern 105 is sensed by one or more photo-detectors of optical sensor 102 to produce one or more signals that indicate the relative movement between optical unit 103 and optical encoder pattern 105. The output signal or signals from optical sensor 102 are then used by the printer to help control the movement of the printing head and/or paper in the printing process.
FIGS. 2A-B illustrate the relationship between optical encoder pattern 105 formed on a code strip 210, a photo-detector 220 of optical sensor 102, and an output signal produced by photo-detector 220 when optical encoder pattern 105 and the optical unit 103 (including photo-detector 220) move relative to each other.
As seen in FIG. 2A, optical encoder pattern 105 is an alternating pattern of rectangular shaped "light" elements 230 and "dark" elements 240, and photo-detector 220 also has a rectangular shape. In many cases, the light elements 230 comprise light-transmitting regions, which may be transparent regions or apertures in the code strip 210, so that light from the optical emitter 101 passes through light elements 230 of code strip 210 to optical sensor 102, but is blocked by dark elements 240 from reaching optical sensor 102. In another alternative arrangement, light elements 230 comprise light-reflecting regions which may be white or shiny, so that light from optical emitter 101 reflects back from light elements 230 of code strip 210 to optical sensor 102, but light is absorbed by dark elements 240 and not reflected to optical sensor 102. The discussion to follow is equally applicable to each of these configurations.
Photo-detector 220 produces an output signal that depends upon the amount of light it receives from optical pattern 105. As optical encoder pattern 105 and optical unit 103 (including photo-detector 220) move relative to each other, the amount of light received by photo-detector 220 varies from virtually no light when photo-detector 220 is aligned with a dark element 240 of optical encoder pattern 105, to a maximum amount of light when photo-detector 220 is aligned with a light element 230 of optical pattern 105. Assuming that optical encoder pattern 105 and optical unit 103 move relative to each other at a constant rate, then FIG. 2B shows the output signal of photo-detector 220.
As can be seen in FIG. 2B, the output signal of photo-detector 220 is a trapezoidal-shaped signal, with a flat top, a flat bottom, and a constant slope between the top and bottom. The arrangement of FIGS. 2A-B pertains specifically to a linear code strip 210. In some cases, a circular code wheel is used in place of the code strip 210, in which case either the light elements 230 and dark elements 240, or the photo-detector 220, has a trapezoidal shape instead of the rectangular shape. In either case, the photo-detector 220 produces the trapezoidal-shaped output signal shown in FIG. 2B.
However, there are some disadvantages to the arrangement illustrated in FIGS. 2A-B. In particular, from a feedback or control system standpoint, the trapezoidal-shaped output signal of the photo-detector is not very desirable. During the "flat spots" as the top and bottom, the photo-detector is not outputting any useful information regarding the relative movement between the optical sensor and the optical encoder pattern. Furthermore, the trapezoidal-shaped output signal is actually a series of ramp functions, and it is well known that a ramp function is not differentiable. So acceleration cannot be obtained. From a feedback or control system standpoint, it would be preferable if the output signal of the photo-detector was instead generally sinusoidal in nature.
What is needed, therefore, is an optical encoder whose photo-detector(s) produce a generally sinusoidal output signal in response to relative movement between the optical encoder pattern and the optical sensor.

Optical encoder with sinusoidal photodetector output signal


The disclosed invention is a grid that monitors a design simulation to support design verification coverage analysis. The disclosed invention includes n ordered axis declarations 72 that each correspond to a functional attribute and list at least two valid functional states, logic expressions 78 that test for the functional states and set axis variables, and a grid declaration 80 that converts the axis variables to a unique linear index value corresponding to the cross-product of the achieved functional states and records hits. The linear index is calculated by multiplying the integer value of each axis variable (except the nth axis variable) by the product of the sizes of each higher-order axis than the axis to which said axis variable corresponds, summing the results, and adding the integer value of the nth said axis variable.

1. Field of the Invention
The present invention relates to design verification in the digital computing field. More particularly, the present invention relates to a coverage analysis tool and method that monitors a simulation test on a digital design to detect and report interesting events and states achieved during the simulation.
2. Description of the Related Art
A digital design performs a finite number of logical functions or operations. For instance, a typical digital design such as a microprocessor might support four separate operations called addition (a), multiplication (m), subtraction (s), and division (d). Within each operation, different specific events may occur. For instance, addition of two negative numbers may occur, or addition of two positive numbers may occur.
A digital design will support many combinations of events where each type of specific event is called a state. In more complex designs, events may happen serially so that the number of states is increased. For instance, the operation sequence addition-multiplication-division (amd) is a different state than the operation sequence addition-multiplication-subtraction (ams). More states exist in the digital design when each a, m, s, and d operation supports various types of operands (i.e., positive, negative, and zero). Each permutation combining possible specific events results in a different state.
Exhaustive verification of modern digital designs such as microprocessors is virtually impossible because such designs may attain an almost incalculable number of states. A designer must therefore determine a sub-list of states that represent the most interesting states. The sub-list of states should include functional events, which are events that can be defined based on the specification of the design, and implementation events, which are specific to how the designer chose to implement the specification. While the sub-list of interesting states is not exhaustive, it usually provides a yardstick for measuring test coverage. To gain an adequate level of confidence that the design is functioning correctly, it is necessary to verify whether the design attains all of these interesting states during operation or simulation.
Verification of digital designs is usually done using a simulator. A simulator is a program that runs the design file of a digital design in order to recreate how the design would perform on a computer chip. A common method for generating test stimulus is to use a random, or directed random, test case generator. With random test case generation, the correctness of the design being simulated is established by having the results predicted automatically by some sort of reference model. The actual checking may take many forms, ranging from comparing the final results in memory to checking internal state cycle-by-cycle. There are major advantages to using random test case generation. Computer programs can generate test cases much faster than people can, so many more design states can be reached in the same amount of time using random test case generation. This is critically important for complex designs which need a reasonable time-to-market. Also, by introducing randomness, the verification engineer can think of a general set of tests that would hit interesting states, and let the computer generate all the special cases. In many cases, the random test generator ends up creating situations that a tester may not have thought to create.
One drawback to random test case generation is that it is difficult to know exactly what is being tested. Consequently, it is difficult to gain an adequate level of confidence that the design is attaining all of the required states determined by the designer to be interesting. A number of approaches have been used to determine when a design has been sufficiently verified using random test case generation. One method is to use statistical data from previous designs to predict the expected bug rate. This requires that the statistical data exist for the same style of design and the same test generation tool. Another method is to simply try as many different test strategies with the random test generator as one can think of, and then run them until the bug rate decreases. A third method is to use coverage analysis tools to quantify the percentage of the existing design states that have been hit.
Existing coverage analysis tools typically traverse the source code of the design to generate a list of unique states to be tracked. Since the resulting coverage data is based purely on the existing source code, the coverage data is very specific to the implementation of the design. There is no way to use the coverage data to evaluate functional coverage, or how much of the specification that details the functional requirements of the design has been tested. It can also be difficult to evaluate how many of the cases that have not been hit are actually interesting. And finally, current source-code generated coverage tools do not generate and track interesting combinations of states, so source-code generated data does not include data on interesting combinations of events.
The present invention introduces a method for evaluating coverage from either a functional or an implementation perspective, including combinatorial coverage. It provides an easy way to write a software monitor to identify an event or state in a design simulation and then log the information concerning attainment of the state into a database for further analysis. Designers can then analyze the database to determine if the simulation provides adequate coverage of a particular list of interesting events. If the simulation does not adequately cover certain events, the cause can then be investigated. The list of events monitored and reported into the database can be driven by the sub-list of events determined by the designer to be interesting.
One way that designers identify interesting combinatorial events is to take the cross product of two or more events. For example, designers typically want to verify design functionality for every possible combination of two back-to-back instructions. Likewise, designers will likely want to test all possible combinations of operands for an instruction. As designs become more complex and capable of executing more unique instructions with more types of operands, more interesting states can be expressed as a cross product of different events.
The assignee of the present invention, Intrinsity, Inc., has developed and patented a new logic design style called N-NARY Dynamic Logic ("NDL"). A new logic design style requires new coding techniques to verify the computer-aided design of the logic circuits and their constituent subcircuits, and NDL is no exception. NDL is a dynamic logic design style fully described in U.S. Pat. No. 6,069,49, titled "Method and Apparatus for a N-NARY Logic Circuit Using 1-of-N Signals", which is incorporated by reference for all purposes and is referred to herein as "The N-NARY Patent." NDL uses a multiphase clock scheme that self-synchronizes the logic flow, thus eliminating the need for static latches and registers and elaborate timing schemes. NDL synchronization is further described in detail in U.S. Pat. No. 6,118,304, entitled "Method and Apparatus for Logic Synchronization," which is incorporated for all purposes and referred to herein as "the Logic Synchronization Patent."
The simulation of NDL is fully described in the following copending patent applications: U.S. patent application Ser. No. 09/405,618, filed 24 Sep. 1999 (24.09.1999), titled "Software Modeling of Logic Signals Capable of Holding More Than Two Values", and U.S. patent application Ser. No. 09/405,474, filed 24 Sep. 1999 (24.09.1999), titled "Four-State Simulation for Non-Binary Logic", both of which are incorporated by reference for all purposes.
As described in further detail in the N-NARY patent, the N-NARY logic family supports a variety of signal encodings, including 1-of-4. In 1-of-4 encoding, four wires are used to indicate one of four possible values. In contrast, traditional static logic design uses two wires to indicate four values, as is demonstrated in Table 1. In Table 1, the A0 and A1 wires are used to indicate the four possible values for operand A: 00, 01, 10, and 11. Table 1 also shows the decimal value of an encoded 1-of-4 signal corresponding to the two-bit operand value, and the methodology by which the value is encoded using four wires.
TABLE 1N-NARY (1-of-4)Signal AN-NARY (1-of-4) Signal A2-bit operand valueDecimal Value1-of-4 wires assertedA1A0AA[3]A[2]A[1]A[0]0000001011001010201001131000
While "traditional" dual-rail dynamic logic also uses four wires to represent two bits, the dual-rail scheme always requires two wires to be asserted, whereas NDL only requires assertion of one wire, thus reducing power and signal noise. Other benefits of NDL over dual-rail dynamic logic are described in the N-NARY Patent. All signals in NDL, including 1-of-4, are of the 1-of-N form where N is any integer greater than one. More than one wire will never be asserted for a valid 1-of-N signal. Similarly, NDL requires that a high voltage be asserted on only one wire for all values, even the value for zero (0).
Any one NDL gate may comprise multiple inputs and/or outputs. In such a case, a variety of different N-NARY encodings may be employed. For instance, consider a gate that comprises two inputs and two outputs, where the inputs are a 1-of-4 signal and a 1-of-2 signal and the outputs comprise a 1-of-4 signal and a 1-of-3 signal. Variables such as P, Q, R, and S may be used to describe the encoding for these inputs and outputs. One may say that one input comprises 1-of-P encoding and the other comprises 1-of-Q encoding, wherein P equals two and Q equals four. Similarly, the variables R and S may be used to describe the outputs. One might say that one output comprises 1-of-R encoding and the other output comprises 1-of-S encoding, wherein R equals four and S equals 3. Through the use of these, and other, additional variables, it is possible to describe multiple 1-of-N signals used in NDL gates that comprise a variety of different encodings.
1-of-N signals used in NDL gates are named according to a signal naming convention that is fully described in a copending patent application, U.S. patent application Ser. No. 09/210,408, titled "Method and Apparatus for N-NARY Hardware Description Language", which is incorporated by reference for all purposes and is referred to herein as "The Hardware Description Patent." The signal naming convention identifies certain information that characterizes the signal, specifically information concerning 1-of-N degree, evaluation, and clock phase. For further details regarding the meaning and interpretation of the various fields in a signal name, the reader is encouraged to refer to the Hardware Description Patent. A typical name for a typical 1-of-N signal might be "disp_valid—4H2", which indicates a 1-of-4 signal described as "disp_valid" th evaluates on the rising edge of the second clock phase. The present invention refers to signals using the signal naming convention as described in the Hardware Description Patent.

Grid that tracks the occurrence of a N-dimensional matrix of combinatorial events in a simulation using a linear index


The present invention relates to a method for stabilizing aqueous dispersions, notably of polymers based on vinylidene fluoride (VDF), and to the use of the stabilized aqueous dispersion thus obtained in electrochemical applications.

Aqueous dispersions of fluoropolymer and applications thereof are widely known in the art.
For example, US 20020193500 (3M INNOVATIVE PROPERTIES COMPANY) discloses a process for preparation of a fluoroelastomer latex, said process comprising the steps of (A) forming an aqueous emulsion of monomers capable of being copolymerized to form a fluoroelastomer; (B) polymerizing said emulsion at a temperature of about 40° C. to 130° C. and a pressure of about 2 to 9 MPa to form a fluoroelastomer emulsion composition; (C) adding a sufficient amount of base to adjust the pH of said fluoroelastomer emulsion composition to between 5 to 9; and (D) concentrating said fluoroelastomer emulsion composition which has a pH of 5 to 9, to form a solids-rich fluoroelastomer latex. The emulsion of step (A) comprises a first monomer selected from vinylidene fluoride (VDF) and tetrafluoroethylene (TFE), at least one other fluorine-containing monomer, a free radical initiator, a fluorinated surfactant and a base. Following the preparation of the fluoroelastomer emulsion composition, its pH is adjusted by addition of a base. The pH of the polymerization reaction mixture should be maintained in the range from 3 to 8, preferably from 5 to 8.
This patent application lists several fluorinated surfactants suitable for use during step (A), as well as fluorinated and non-fluorinated surfactants suitable for further stabilizing the composition. However, this patent application only discloses fluoroelastomers, i.e., fluoro-carbon based synthetic rubbers, but it is completely silent about semi-crystalline polymers. In addition, this patent application neither faces the problem of providing a latex suitable for use in battery application not provides any hint to select a surfactant for this specific use.
Similarly, EP 1897902 A (DAIKIN IND LTD) Dec. 3, 2008 discloses a method of producing an aqueous fluoropolymer dispersion comprising a step (1) of adding a nonionic surfactant to an aqueous fluoropolymer dispersion to be treated, a step (2) of phase-separating into a supernatant phase and an aqueous fluoropolymer dispersion phase following the step (1), and a step (3) of recovering the aqueous fluoropolymer dispersion phase by removing the supernatant phase, stirring being provided in the step (2). According to this document, the addition of the nonionic surfactant may be made after adjustment of the aqueous fluoropolymer dispersion to be treated to pH 3 to 12 with aqueous ammonia, for instance. Among fluoropolymers, is mention made of VDF-based polymers (such as VDF/HFP copolymers, VDF/chlorotrifluoroethylene [CTFE] copolymers, VDF/TFE copolymers, VDF/perfluoro(alkyl vinyl ether) [PAVE] copolymers, VDF/TFE/HFP copolymers, VDF/TFE/CTFE copolymers and VDF/TFE/PAVE copolymers).
US 20100304270 (ARKEMA INC.) discloses an aqueous fluoropolymer, preferably polyvinylidene fluoride (PVDF), composition for the manufacture of electrodes for use in non-aqueous-type electrochemical devices, such as batteries and electric double layer capacitors. The composition contains aqueous PVDF binder, and one or more powdery electrode-forming materials.
Vinylidene fluoride (VDF) polymers are known in the art to be suitable as binders for the manufacture of electrodes and/or composite separators, and/or as coatings of porous separators for use in non-aqueous-type electrochemical devices such as batteries, preferably secondary batteries, and electric double layer capacitors.
In this field, a continuous quest exists for aqueous dispersions of VDF polymers possessing all required properties for being used in the field of components for secondary batteries, including notably ability to deliver cohesion with electrode active materials and/or with composite separators' inorganic fillers, ability to ensure adhesion to metal collectors, separator porous substrates, stability/non-dissolution towards liquid electrolyte solutions and prevention of contamination with chemicals possibly interfering with electrochemical reactions (e.g. fluorosurfactant having not sufficient electrochemical stability), while yet possessing adequate properties for processing, including shear stability during formulation and casting, acceptable shelf life.
Now, techniques for manufacturing VDF dispersions are generally based on aqueous emulsion polymerization, typically in the presence of fluorinated emulsifiers, which are generally difficult to be removed from resulting dispersions, and which may have detrimental effects as contaminants in electrochemical devices parts. While attempts to reduce or even eliminate fluorosurfactants in emulsion polymerization of VDF so as to deliver stable VDF polymers dispersions free therefrom are known, those techniques are understood to be based to self-stabilization of polymer chains through end groups' chemistry. Increasing molecular weight would reduce overall concentration of chain ends, leading hence to lack of stabilization phenomena.
U.S. Pat. No. 5,880,204 (ALLIED SIGNAL INC.) discloses room temperature coalesceable aqueous fluoropolymer dispersions comprising particles of a block copolymer having a first semi-crystalline block and a second amorphous block, wherein first and second block are generally VDF or CTFE copolymers, and second block comprises generally a so-called "cure-site provider", which can be notably an acid such as acrylic acid. Generally the fluoropolymer, as a whole, possesses Mw of 10,000 to 1,000,000 (hence ranging from low to extremely high molecular weight). These dispersions are taught useful as floor polishes. Generally, latices are prepared in the absence of surfactants, using a redox initiating system at relatively low polymerization temperature.
WO 2013/010936 (SOLVAY SPECIALTY POLYMERS ITALY S.P.A.) pertains to an aqueous composition comprising: (A) an aqueous latex comprising at least one vinylidene fluoride (VDF) polymer [polymer (F)] comprising recurring units derived from vinylidene fluoride (VDF) and at least one (meth)acrylic monomer (MA) which is preferably acrylic acid (AA), (B) at least one powdery electrode material, and (C) optionally, less than 10 percent by weight, based on the total weight of the aqueous composition, of at least one organic solvent (S), wherein the polymer (F) in the aqueous latex is under the form of primary particles having an average primary particle size of less than 1 μm, as measured according to ISO 13321. This document also pertains to a process for manufacturing an electrode using said aqueous composition, to an electrode comprising a metal substrate coated on at least one surface with said aqueous composition and to use of said electrode for manufacturing a non-aqueous-type electrochemical device. The latices are prepared by aqueous emulsion polymerization at pressure of 20 to 70 bar and temperatures of 60 to 135° C., preferably 90 to 130° C., in the presence of a micro-emulsion or of a fluorosurfactant.
WO 2015/059155 (SOLVAY SA.) is directed to an electrode-forming composition comprising: (a) an aqueous latex comprising at least one fluoropolymer [polymer (F)] comprising recurring units derived from vinylidene fluoride (VDF), at least one hydrogenated monomer, which is preferably AA, and, optionally, at least one other fluorinated monomer different from VDF, and, homogeneously dispersed therein, (b) at least one powdery electrode-forming material consisting of Sulphur, (c) at least one powdery electrically conducting material, wherein the polymer (F) in the aqueous latex is under the form of primary particles having an average primary particle size of less than 1 μm, as measured according to ISO 13321. This document also pertains to a process for the manufacture of said composition and to use of said composition in a process for the manufacture of a positive electrode for a Lithium-Sulphur battery. The latices are prepared by aqueous emulsion polymerization at pressure of 20 to 70 bar and temperatures of 60 to 135° C., preferably 90 to 130° C., possibly in the presence of a micro-emulsion or a fluorosurfactant.
WO 2008/129041 (SOLVAY SOLEXIS S.P.A.) is directed to a linear semi-crystalline copolymer comprising recurring units derived from vinylidene fluoride (VDF) monomer and at least one hydrophilic (meth)acrylic monomer which is statistically distributed in the polymer chain, and to a method for its manufacture by suspension polymerization combined with step-wise addition of acrylic monomer.
WO 2013/120858 (SOLVAY SPECIALTY POLYMERS ITALY S.P.A.) is directed to a process for the manufacture of a composite separator for an electrochemical cell, said process comprising the following steps: (i) providing a substrate layer; (ii) providing a coating composition comprising:                an aqueous latex comprising at least one VDF polymer latex, and        at least one non-electroactive inorganic filler material;(iii) applying said coating composition onto at least one surface of said substrate layer to provide a coating composition layer; and(iv) drying said coating composition layer.
WO 2014/095907 (SOLVAY SPECIALTY POLYMERS ITALY S.P.A.) pertains to a process for the manufacture of a dense film, said process comprising providing a solid composition of a VDF fluoropolymer comprising carboxylic groups and at least one PAO; and processing said mixture in molten phase thereby providing a dense film, which can be used as dense separator in electrochemical devices.
However, the above mentioned documents do not specifically face the problem of stabilizing the fluoropolymer dispersion.

Method for stabilizing aqueous dispersions of fluorinated polymers


Described herein are systems and methods for suppressing speckle noise in ultrasound imaging. In an embodiment, speckle noise suppression is provided by incoherently summing echo waves that impinge the active aperture of the transducers. This incoherent summation prevents echo waves from destructively interfering and therefore prevents the signal ‘nulls’ that characterize speckle noise. In an exemplary embodiment, the incoherent summation is performed by sub-dividing a transducer into a plurality of smaller transducers and incoherently summing the electrical signals from the smaller transducers. In one exemplary embodiment, each of the smaller transducers is coupled to a separate rectifier, which rectifies the electrical signal from the respective transducer into a rectified signal. The rectified signals from the rectifiers are then summed to provide the incoherent summation.

Ultrasound imaging is used in the medical field to image inside a patient. Ultrasound imaging may be performed with an internal ultrasound imager received within the patient (e.g., intravascular ultrasound system) or an external ultrasound imager placed on the patient's skin. An ultrasound imager comprises one or more ultrasound transducers that emit ultrasonic waves into the patient. The ultrasound waves are reflected back to the transducer by layers of tissue or other structures in the patient as echo waves. A transducer converts received echo waves into electrical signals that are representative of the strength of the echo waves. The electrical signals are processed by an ultrasound image processor into an ultrasound image.
Current ultrasound transducers are coherent sensing devices that suffer from an imaging phenomenon known as speckle noise. Speckle noise is caused by the interference, both constructive and destructive, of echo wave fronts originating from scattering sources that are too small to be resolved by the transducer. A simple example of this is illustrated in FIGS. 1a and 1b. FIG. 1a shows an ultrasound wave 112 that is emitted from a transducer 110 and propagates towards a structure in the body, e.g., blood vessel wall 115. The ultrasound wave 112 is typically a periodic pressure wave having a frequency in the megahertz range. FIG. 1b shows an example of echo wave fronts 122a and 122b originating from two scattering sources 120a and 120b that are too small to be resolved by the transducer 110. The transducer 110 coherently sums the echo wave fronts 122a and 122b impinging on the active aperture of the transducer 110, and produces an electrical signal based on the coherent sum. If the echo wave front 122a impinges the transducer 110 at its peak and the echo wave front 122b impinges the transducer 110 at its trough, then the echo wave fronts 122a and 122b destructively interfere, and tend to cancel each other out. This destructive interference results in a dark spot in the ultrasound image at the blood vessel wall 115 even though the blood vessel wall 115 should appear bright in the image. Typically, scattering sources are distributed throughout the area of the body being imaged. The destructive interference of echo wave fronts originating from these scattering sources give rise to dark spots in the image that characterize speckle noise.
Speckle noise reduces the quality of the ultrasound image and, therefore, the ability of physicians and computers to perform diagnoses based on the image. Speckle noise is one reason many image processing algorithms, that work reasonably well for other imaging modalities such as CT or Magnetic Resonance (MR), do not work well for ultrasound images.
Therefore, there is a need in the art to suppress speckle noise in ultrasound imaging.

Ultrasound imaging with speckle suppression via direct rectification of signals


The present invention relates to a mobile terminal enabling a user to more conveniently use the terminal and a method of controlling therefor. According to at least one of embodiments of the present invention, in case of transceiving an image using a wearable device of a glasses form, it may easily target an external device, which becomes a target with which the image is transceived.

1. Field
The present invention relates to a mobile terminal enabling a user to more conveniently use the terminal and a method of controlling therefor.
2. Background
A mobile terminal is a device which may be configured to perform various functions. Examples of such functions include data and voice communications, capturing images and video via a camera, recording audio, playing music files and outputting music via a speaker system, and displaying images and video on a display. Some terminals include additional functionality which supports game playing, while other terminals are also configured as multimedia players. More recently, mobile terminals have been configured to receive broadcast and multicast signals which permit viewing of contents, such as videos and television programs.
Generally, terminals can be classified into mobile terminals and stationary terminals according to a presence or non-presence of mobility. And, the mobile terminals can be further classified into handheld terminals and vehicle mount terminals according to availability for hand-carry.
There are ongoing efforts to support and increase the functionality of mobile terminals. Such efforts include software and hardware improvements, as well as changes and improvements in the structural components which form the mobile terminal.
Recently, inconvenience of operating a terminal is pointed out. In particular, it is a fair fact that if a hand or both hands are not free (in case of carrying an object by hands or in case of exercising/driving and the like), operating the terminal is inconvenience. Hence, a study on a new way of operating the terminal is under discussion. The study is focusing on a mobile terminal capable of being worn on a body of a person. This sort of terminal is called a wearable device (or wearable computer). Representative examples of the wearable device include a terminal of a watch form and a terminal of a glasses form.
Since those kinds of wearable devices are always worn on a part of a body of a user, there exists a merit in terms of mobility. On the contrary, since there exist a relatively small display and a limitation of a user input means, operation of the wearable devices may cause inconvenience.
Hence, it is necessary to perform a study on a wearable device enhancing user convenience in a manner of reducing inconvenience of operating the wearable devices and a method of controlling therefor.

Mobile terminal and method of controlling therefor


A charge coupled device of the present invention includes a charge transfer region layer and a gate insulation film that are formed in the stated order on a semiconductor substrate, first gate electrodes formed at predetermined spaces on the gate insulation film, and second gate electrodes arranged between the first gate electrodes with at least silicon oxide films being interposed there between. Each silicon oxide film has constricted portions where the silicon oxide film is in contact with the gate insulation film, and electric insulation films are formed on the constricted portions so as to form sidewalls. This configuration decreases the charge transfer efficiency and increases a dielectric breakdown voltage between gate electrodes. Thus, a charge coupled device having high performance and high dielectric strength is provided.

1. Field of the Invention
The present invention relates to a charge coupled device suitably employed in a solid-state imaging device for use in, for instance, a digital camera, and to the production thereof
2. Related Background Art
A charge coupled device (hereinafter referred to as CCD) is a device having a structure in which a multiplicity of metal oxide semiconductor (MOS) structure electrodes are arranged on a surface of a semiconductor, and generally is used as a so-called solid-state imaging device in various types of electronic cameras, facsimiles, etc.
FIG. 2 illustrates a cross-sectional structure of a prior art CCD. A charge transfer region 22 is formed on a P-type silicon substrate 21 in which an impurity is doped, and a gate insulation film 23 is formed on the charge transfer region 22. On the gate insulation film 23, first gate electrodes 24 and second gate electrodes (transfer electrodes) 27 are formed alternately. When a voltage is applied to the gate electrodes, charge stored under each gate electrode is transferred from one electrode to another successively, and the charge is outputted as a voltage at an output section. 28 denotes a potential well.
The following will describe a method for producing the prior art CCD. First, as shown in FIG. 3A, the charge transfer region 22 is formed on the P-type silicon substrate 21, and the gate insulation film 23 is formed on the charge transfer region 22. Subsequently, the first gate electrodes 24 are formed on the gate insulation film 23 by patterning.
Next, as shown in FIG. 3B, the first gate electrodes 24 are oxidized so as to be covered with a silicon oxide film 25. Subsequently, as shown in FIG. 3C, the second electrodes 27 are formed on the gate insulation film 23 so that each is arranged between adjacent first gate electrodes 24. Thus, the first and second gate electrodes 24 and 27 are arranged alternately on the gate insulation film 23, and the silicon oxide film 25 is formed between the gate electrodes, whereby the gate electrodes are insulated electrically from one another by the silicon oxide film 25.
In the case where this method is used, the forming rate of the silicon oxide film 25 decreases with increasing proximity to the gate insulation film 23 since the supply of oxygen decreases. Therefore, as shown in the drawings, on side faces of the first gate electrode 24, the thickness of the silicon oxide film 25 decreases (the silicon oxide film 25 is constricted) with increasing proximity to the gate insulation film 23. The second gate electrode 27 is formed in a state of being in contact with the silicon oxide film 25, and hence, it is formed to have acute-angle edges 32 in its base part on the gate insulation film 23. When a voltage is applied to each gate electrode in the foregoing state, sometimes an electric field is concentrated at the edges 32, thereby causing dielectric breakdown between the first gate electrode 24 and the second gate electrode 27.
To cope with the foregoing problem, conventionally the varying of the conditions for the oxidization of the first gate electrode 24 has been attempted, or alternatively, the increase in the dielectric breakdown voltage between the gate electrodes was attempted by increasing a film thickness t2 (FIG. 3B) of the silicon oxide film 25 on the first gate electrode 24.
However, the foregoing problem has not been solved by any one of the foregoing methods, and particularly the increase in a film thickness t2″ (FIG. 3B) of the silicon oxide film 25 necessarily increases a distance g2 (FIG. 3C) between the gate electrodes, thereby impairing the charge transfer efficiency of the CCD. Furthermore, at the same time, a difference t2′–t2″ between the film thickness t2′ of the silicon oxide film 25 on the side faces of the first gate electrode 24 and the film thickness t2″ thereof in contact with the gate insulation film 23 increases, thereby narrowing the angle of the edges 32 on the gate insulation film 23. As a result, the dielectric breakdown tends to occur more easily.

Matsushita Electric Industrial Co., Ltd.


A solid-state image pickup device in which a plurality of optoelectric transducing elements are vertically and horizontally arranged into a matrix array, groups of optoelectric transducing elements arrayed in first rows serve as picture elements having a red spectral characteristic, groups of optoelectric transducing elements arrayed in second rows serve as picture elements having a blue spectral characteristic, and vertical charge transfer paths and groups of picture elements arrayed in the column direction are alternately arranged. In accordance with the invention, segmental portions of each of the vertical charge transfer paths, which positionally correspond to respective ones of the picture elements, include portions where charge transfer electrodes are layered and portions where no transfer electrodes are layered, an impurity is distributed in predetermined portions of the vertical charge transfer path under the charge transfer electrodes and the portions with no charge transfer electrodes in the charge transfer direction, thereby to set up potential levels of different depths, potential wells, that are caused by applying a signal of a predetermined voltage to the charge transfer electrodes when an image is being sensed, are used as picture elements of green, and signal charge is transferred by applying a drive signal recurring at predetermined periods to the charge transfer electrodes.

The present invention relates to a solid-state image pickup device constructed with charged coupled devices (CCDs) of the interline transfer type, and more particularly to a solid-state image pickup device improved in that the number of picture elements is increased and its vignetting factor is increased by applying the vertical charge transfer paths within a light-receiving area to photosensitive portions (picture elements).
A conventional solid-state image pickup device will be described with reference to FIG. 6. In FIG. 6, reference numeral 1 designates a light-receiving area; 2, a horizontal charge transfer path; and 3, an output amplifier. Photodiodes are vertically and horizontally arranged into an n.times.m matrix array within the light-receiving area 1. Color filters of green (G) are layered on the light incident surfaces of the photodiodes linearly arrayed in even-numbered rows, thereby to form pixels with green spectral sensitivity a.sub.2,1, a.sub.2,2. . . , a.sub.2,m, a.sub.4,1, a.sub.4,2, . . . , a.sub.4,m, a.sub.n,1, a.sub.n,2, . . . , a.sub.n,m.
Vertical charge transfer paths l.sub.1, l.sub.2, . . . , l.sub.m and groups of blue and green pixels linearly arrayed in columns are alternately arranged. Transfer electrodes (not shown) made of polysilicon, which are used for transferring signal charge in the vertical direction in response to drive signals based on the so-called four-phase drive system, are layered on respective ones of the vertical charge transfer paths.
The terminals of the vertical charge transfer paths l.sub.1, l.sub.2, . . . , l.sub.m are coupled with the horizontal charge transfer path 2, while being disposed side by side. The output amplifier 3 is provided at the output terminal of the horizontal charge transfer path 2.
A structure of the light-receiving area 1 will be described in detail with reference to FIG. 7.
The structure in the vicinity of the blue pixels a.sub.1,1, a.sub.1,2, and a.sub.1,3 and the green pixels a.sub.2,1, a.sub.2,2, and a.sub.2,3 will be described as a typical example for ease of explanation. In the figure, the blue and green pixels are separated from the vertical charge transfer paths l.sub.1, l.sub.2, and l.sub.3 by channel stoppers as shaded. Pairs of transfer electrodes G.sub.1 and G.sub.2, and G.sub.3 and G.sub.4, each pair being allocated for each linear array of the pixels in the row, are layered on the upper surfaces of the vertical charge transfer paths l.sub.1, l.sub.2, and l.sub.3 (except the upper surfaces of the blue and green pixels). In operation, drive signals .phi..sub.1, .phi..sub.2, .phi..sub.3, and .phi..sub.4 based on the four-phase drive system are applied to the transfer electrodes. In response to the drive signals, potential wells (referred to as transfer elements) for transferring signal charge are generated in the vertical charge transfer paths l.sub. 1, l.sub.2, and l.sub.3.
A transfer gate Tg.sub.1 is inserted between one end of each blue pixel and a transfer element adjacent to the pixel. A transfer gate Tg.sub.2 is inserted between one end of each green pixel and a transfer element adjacent to the pixel. When high voltage signals are applied to the related transfer gates G.sub.2 and G.sub.4, the transfer gates Tg.sub.1 and Tg.sub.2 are rendered conductive.
A sectional structure of the vertical charge transfer paths as taken on line X--X in FIG. 7 will be described with reference to FIG. 8. The transfer electrodes G.sub.1, G.sub.2, G.sub.3 G.sub.4, . . . , which are made of polycrystal, are formed on a silicon oxide film (SiO.sub.2) to serve as a gate oxide film layer, which is formed on the surface of a P-well layer in a semiconductor substrate. In this instance, when an "H" (high) drive signal is applied to the transfer electrodes G.sub.1 and G.sub.2, and an "L" (low) level drive signal is applied to the transfer electrodes G.sub.3 and G.sub.4, a deep potential well is formed under the electrodes G.sub.1 and G.sub.2, and a shallow potential barrier is formed under the transfer electrodes G.sub.3 and G.sub.4. Signal charge can be stored in the well. The potential wells of the transfer elements (as indicated by shading in FIG. 6) are deepened when an image is picked up, and are used as red pixels. For example, in FIG. 7, color filters of red (R) are formed on the upper surfaces of the transfer electrodes G.sub.1, G.sub.3, and G.sub.3. When an image is to be sensed, the drive signals .phi..sub.1 to .phi..sub.3 applied to those electrodes are set to the "H" level, and the drive signal .phi..sub.4 applied to the transfer electrode G.sub.4 is set to the "L" level. The transfer elements by the electrodes G.sub.1 to G.sub.3 are used as red pixels. Those pixels are separated by the potential barrier under the transfer electrode G.sub.4. The pixels of the same color can be formed by applying the drive signals .phi..sub.1 to .phi..sub.4 to the remaining transfer electrodes in the same phase relation.
An image pickup operation of the solid-state image pickup device thus arranged will be described.
During an exposure period, the related drive signals (e.g., .phi..sub.2 to .phi..sub.4) are set to the "H" level, and the remaining drive signal (e.g., .phi.) is set to the "L" level. With such level settings, groups of red pixels are generated in the vertical charge transfer paths. The red pixels thus generated, and the blue and green pixels as constructed with the photodiodes, accumulate signal charge. After the exposure is completed, the red signal charge is transferred toward the horizontal charge transfer path 2 using the four-phase drive system.
In synchronism with the transfer operation, all of the red pixel signals are read out of the horizontal charge transfer path 2. Then, the drive signals whose voltage is higher than a normal voltage are applied to the related transfer electrodes. With voltage is applied, the transfer gates Tg.sub.1 associated with the blue pixels are made conductive and the signal charges of the blue pixels are transferred to the vertical charge transfer path. The transfer gates Tg.sub.1 are then made nonconductive again. Following this, the blue signal charge is transferred toward the horizontal charge transfer path 2 by the four-phase drive system. In synchronism with the transfer operation, all of the blue pixel signals are read out on the horizontal charge transfer path 2. Next, the drive signals whose voltage is higher than a normal voltage are applied to the related transfer electrodes. With application of the high voltage, the transfer gates Tg.sub.2 associated with the green pixels are made conductive, and the signal charges of the green pixels are transferred to the vertical charge transfer path. The transfer gates Tg.sub.2 are then again rendered nonconductive. Following this, the green signal charge is transferred toward the horizontal charge transfer path 2 by the four-phase drive system. In synchronism with the transfer operation, all of the green pixel signals are read out on the horizontal charge transfer path 2.
In this way, the pixel signals are read out every color in an area-sequential scan manner. The pixel signals of these colors thus obtained are equal to one another in number ((n/2).times.m) and resolution, as seen from FIG. 6.
When an image is reproduced by forming luminance signal and color signals from the pixel signals in such image pickup operation, the perceived resolution of the reproduced image becomes better as the high frequency content of the luminance signal is increased. In this respect, there is a strong demand for developing solid-state image pickup devices of high spatial sampling frequencies for the color pixels.

Solid state image pickup device in which picture elements of green are generated in vertical charge transfer paths


An azolylmethylidenehydrazine derivative represented by the formula (I)

Generally, antifungal agents are used for the treatment of superficial mycosis (trichophytosis, tinea versicolor, cutaneous candidiasis etc.). In recent years, therapeutic agents for tinea pedis such as luliconazole, amorolfine, lanoconazole and the like, which have a superior anti-Trichophyton activity, and therapeutic agents for tinea unguium such as terbinafine and itraconazole have been clinically applied. Nevertheless, the number of patients has not decreased, and the number of domestic patients with tinea pedis is estimated to be 25 million and that of domestic patients with tinea unguium is estimated to be 12 million.
Normally, the treatment of tinea pedis takes 4 weeks. However, the necessity of 4-month topical treatment for complete cure has been reported. When subjective symptoms such as flare, itch and the like disappear, patients cease treatment on self-judgment, which permits fungi present in the affected part to grow and often cause recurrence or relapse. Furthermore, reinfection with Trichophyton unleashed by family or patients themselves is considered to also prevent the number of tinea pedis patients from decreasing. Therefore, the development of an external antifungal agent which completely cures tinea pedis by application for a short period of time and causes less relapse has been desired.
Among the superficial mycosis, tinea unguium is particularly intractable, and commercially available external antifungal agents are not expected to penetrate thick nail plates. Therefore, oral antifungal agents such as terbinafine, itraconazole and the like are generally used for the treatment. Since the treatment requires oral administration of the medicament for at least 3 months, medication compliance of the patients is low. Moreover, while many of the tinea unguium patients are persons of middle or advanced age or elderly persons, patients with pre-existing disease such as diabetes and the like often interrupt or cease treatment due to side effects of oral preparation (e.g., hepatopathy, gastrointestinal disorder and the like) or drug interaction. These make it difficult to completely cure tinea unguium and cause many incidents of recurrence. Hence, an antifungal agent highly effective against tinea unguium by topical application free from systemic side effects and drug interaction is demanded in clinical practice.
Since Trichophyton parasitizes in the keratinous tissues of stratum corneum layer, nail and hair, for an antifungal agent to exhibit a superior treatment effect, (1) superior anti-Trichophyton activity, (2) good penetrability and accumulability in stratum corneum, and (3) less decrease in the activity due to adsorption to keratin, a keratinous component, are required. Many of the commercially available superficial mycosis therapeutic agents are superior in the anti-Trichophyton activity and penetrability and accumulability in the stratum corneum, but show high adsorbability to keratin, as a result of which the activity decreases in the stratum corneum layer (see, for example, non-patent document 3). This is considered to be one of the reasons why a treatment by application of commercially available antifungal agents cannot cure tinea pedis or tinea unguium in a short time.
Inflammation, inflammation causing allergic disease and allergic reaction are generally divided into type I to type IV. In type I, inflammation and allergic reaction mainly in mastocytes are induced, as observed in allergic rhinitis, urticaria, pruritus and the like. Such immediate phase inflammation and allergic reaction are induced by chemical mediators such as histamine, leukotriene and the like, which are released from mastocytes, and anti-histamine drugs and chemical mediator-free suppressants and the like show treatment effects. In the late phase reaction following the immediate phase, intradermal infiltration of many eosinophils to occur to further aggravate inflammation. While type IV reaction is seen in diseases such as atopic dermatitis, contact dermatitis, psoriasis and the like, the treatment effects of anti-histamine drugs and chemical mediator-free suppressants are limited, and therefore, steroids are used as main therapeutic drugs. In addition, immunosuppressants such as cyclosporine, tacrolimus and the like show treatment effects against these diseases. However, those medicaments show various side effects. Steroids cause side effects such as infections, skin atrophy, diabetes and the like. Tacrolimus causes side effects such as severe skin irritation and the like in atopic dermatitis patients (see, for example, non-patent document 1). In consideration of the above, the development of a safer anti-inflammatory agent or antiallergic agent for inflammation and allergic reactions of type I, type IV and the like has been desired.
While compounds having an azolyl group such as triazolyl group, imidazolyl group and the like and a hydrazone structure in a molecule have been reported (see, for example, non-patent document 2 and patent documents 1 to 3), they have different structures of —N(R1)(R2) in the formula (I) from that of the present invention. Moreover, usefulness as an antifungal agent, anti-inflammatory agent or antiallergic agent is not described.                [patent document 1] JP-A-63-227586        [patent document 2] JP-A-6-161136        [patent document 3] WO 2004099371        [non-patent document 1] Dermatologic Therapy, 19(2), 118-126, 2006        [non-patent document 2] Heterocycles, 23(9), 2183-2186, 1985        [non-patent document 3] Antimicrobial Agents and Chemotherapy, 46(12), 3797-3801, 2002

Azolylmethylidenehydrazine derivative and use thereof

Abstract: wherein Ar is an aryl group optionally having substituent(s) or a heteroaryl group optionally having substituent(s), R1 and R2 are the same or different and each is an alkyl group, a cycloalkyl group, an aralkyl group optionally having substituent(s), an aryl group optionally having substituent(s), a heteroarylalkyl group optionally having substituent(s), or R1 and R2 are bonded to each other to form a nitrogen-containing heterocyclic group optionally having substituent(s), and X is CH or a nitrogen atom, or a pharmacologically acceptable salt thereof is useful as a medicament, particularly as an antifungal agent, or an anti-inflammatory agent or an antiallergic agent.


A system and method for extracting content from unstructured sources is disclosed. The method includes analyzing web pages of a website, storing text and image data for each web page of the website, extracting a plurality of entities from the web page data, scoring each entity of the plurality of entities to provide an overall score for each entity, and defining a product based on the plurality of entities and the overall score for each entity.

1. Field of the Invention
The invention relates generally to databases. More particularly, the present invention relates to a system and method for extracting content from unstructured sources.
2. Description of the Prior Art
Solutions are known to extract content from unstructured sources such as content from web pages on websites. Accordingly, such methods have the objective of collecting data from websites by parsing web pages with the intent to use the data for other applications.
The problem with traditional solutions for extracting unstructured content from web pages on a website is the inability to accurately extract specific entities amongst all the unstructured data found on a web page. Another problem with traditional solutions for extracting unstructured content from web pages on a website is the inability to effectively identify and remove poor data collected through the parsing process. A still further problem with traditional solutions for extracting unstructured content from web pages is the inability to automatically determine the location of specific entities based on their position within a website.

System and method for content extraction from unstructured sources


A sensor characteristic correction device is configured to detect a characteristic of a first sensor arranged upstream of a catalyst 6 in an exhaust passage 4 of an internal combustion engine 2, and a characteristic of a second sensor that is an air-fuel sensor 12 arranged downstream of the catalyst 6, to calculate a first air-fuel ratio based on the characteristic of the first sensor, and calculates a second air-fuel ratio based on the characteristic of the second sensor, to detect, when the catalyst 6 is in an inactive state after start-up of the internal combustion engine 2, a difference between the first characteristic and the second characteristic or a difference between the first air-fuel ratio and the second air-fuel ratio, and to correct the responsiveness of the first or the second sensor in accordance with the difference.

For example, in Patent Literature 1, a failure detection apparatus of an air-fuel ratio control apparatus which includes air-fuel ratio sensors disposed at positions before and after a catalyst, respectively, is disclosed. In this apparatus, a difference between the outputs of the air-fuel ratio sensors disposed before and after the catalyst is used to determine a failure of the air-fuel ratio sensor that is arranged on the upstream side or a failure of a catalytic converter. Further, in this apparatus, the output of the air-fuel ratio sensor on the downstream side is corrected based on a standard output, and the output of the air-fuel ratio sensor on the upstream side is corrected using the air-fuel ratio sensor on the downstream side.


A lossless (or low loss) transmission line can be constructed using an auxiliary conductor inductively coupled to the primary conductor and driven by the primary conductor through an active shunt network distributed along the transmission line. The auxiliary conductor is placed close enough to the primary conductor so that the two conductors have a substantial amount of mutual inductance compared to their self-inductance. The transmission line can be operated in differential mode. In one embodiment, a combination of conductance and transconductance are used to cancel losses and control dispersion in the transmission line for high frequency signal transmission. Transconductance is achieved in a differential transmission line by inducing a signal from each transmission line into closely coupled parallel lines, adding active elements between each of the coupled lines to a common ground plane and controlling the current through each active element by the signal on the opposite transmission line.

At high frequencies, for example, at or above 1 GHz the propagation of electrical signals along conducting wires is hampered by the effect of losses. Such losses typically cause attenuation as well as dispersion of the signals. If the signal represents a stream of digital data, dispersion causes smoothing of temporal edges, limiting the rate at which digital symbols can be transmitted without intersymbol interference. Attenuation also makes it difficult to identify digital symbols.
It has been found useful to use a transmission line for a variety of purposes, one such purpose being as a delay line. However, attenuation and/or dispersion of the signal at high frequencies, limits the usefulness of transmission lines as delay line elements.
One system for controlling attenuation and/or dispersion in a primary conductor is by use of an auxiliary conductor inductively coupled to the primary conductor. The auxiliary conductor is driven by the primary conductor through an active shunt network distributed along the transmission line. In a variation of this system, two pairs of conductors including a first and second primary conductor and a first and second auxiliary conductor can be operated in differential mode. As will be seen later, the distributed active shunt network can be particularly simple in differential mode.

System and method for providing a lossless and dispersion-free transmission line


A device, by which an unadulterated visibility range can be determined that is independent of the scattering-medium characteristics, determines according to the LIDAR principle the instantaneous visibility range from backscatter light reflected in the scattering medium in front of a vehicle. An evaluation unit is also provided which normalizes a plurality of backscatter measuring curves recorded in succession over time. It forms an average measuring curve from the normalized measuring curves, and derives from at least one measured value of the averaged measuring curve, a visibility range which is independent of the backscattering characteristics of the scattering medium. Using this visibility range thus ascertained, an adaptive compensation of the instantaneously ascertained visibility range is carried out in the evaluation unit.

The present invention relates to a device for measuring visibility range, particularly for motor vehicles, which has at least one optical transmitting element, at least one optical receiving element and a measuring-signal evaluation unit which ascertains an instantaneous visibility range from the light reflected from one or more space zones which are at different distances.
Such a device is known from German Patent No. DE 196 29 712 This known device measures backscattering according to the LIDAR principle. In this case, a light transmitter (e.g. a laser or a photodiode) emits light pulses into the surroundings located in front of a vehicle. Depending on the scattering medium (e.g., fog, snow, rain, smoke, etc.) in the surroundings in front of the vehicle, a greater or lesser portion of the light is reflected after the interaction with the scattering medium, and received by one or more receiving elements (e.g. photodiode). The visibility range is ascertained from the relationship of emitted light to reflected light. However, there are several interference effects on the transmission path of the light which influence the received signals, and thus invalidate the visibility-range measuring result. Sources of error when measuring the visibility range are, for example, a change in the transmitting power of the emitted light because of temperature changes or aging of the transmitting element, for instance, or soiling of the optical system pre-connected to the transmitting and receiving elements, or soiling of the motor-vehicle windshield through which the emitted and received light pulses pass. To eliminate these interference effects, according to the related art mentioned, the backscatter light is determined from two space zones which are at different distances. The indicated interference effects can be eliminated by forming the ratio of the received signals.
It turns out that the measuring signals received by the optical receiver are very strongly dependent on the backscattering properties, i.e. on the type of scattering medium. For example, in the case of fog, the backscatter characteristics are dependent on the droplet-size distribution. However, an unadulterated visibility-range measurement is only possible when the type of scattering medium has no influence on the visibility-range measurement. Therefore, an object of the present invention is to provide a device of the type indicated at the outset which permits a visibility-range measurement that is independent of the type of scattering medium.
The indicated objective is achieved, in that means are provided which normalize a plurality of successively recorded measuring curves, each of which is composed of a plurality of measured values of light reflected from space zones at different distances. The means form an average measuring curve from the normalized measuring curves, and derive from at least one measured value of the averaged measuring curve, a visibility range which an evaluation unit uses for the adaptive compensation (adjustment) of an instantaneously ascertained visibility range. The instantaneous visibility range is determined according to the related art from the light reflected from one or more space zones that are at different distances.
The instantaneous visibility range is measured without great time delay, and can be implemented repeatedly within a second. The instantaneous visibility range is compensated according to the present invention using a measured visibility range resulting from a longer-lasting averaging process of past measured values, with the goal of eliminating the influence of the scattering-medium characteristics on it. The averaging process for determining the visibility range used as compensation makes it superfluous to send out light signals having very high levels which represent a danger for the eyes. The ascertainment of the visibility range that is independent of the scattering medium, which is more tedious because of the averaging process, does not delay the actual measurement of an unadulterated visibility range, since it is merely used as a compensation variable for the instantaneous visibility range that is determined very quickly, but not without influence by the type of scattering medium.
Accordingly, it is expedient that the means normalize all measuring curves, recorded in succession over time, to the maximum value of the measuring curves.
A classifier, operating according to the fuzzy principle, advantageously divides the respectively ascertained, compensated visibility ranges into distance classes.
The means advantageously set a plurality of measured values from the averaged measuring curve in relation to one another, and derive the visibility range therefrom.
Additional means can be provided which acquire from the visibility range, which has been derived from the averaged measuring curve, information about the type of medium impairing the visibility range.
The present invention shall now be explained in greater detail.