It is a problem to realize, by a reduced number of processes than that of the conventional, a reliable active-matrix liquid crystal display device having a high opening ratio for high-definition display. The present invention is characterized by: forming a gate electrode and source and drain interconnections in the same process, forming a first insulating film covering the interconnections, forming an upper light-shielding film on the first insulating film, forming a second insulating film on the upper light-shielding film, partially etching the first and second insulating films to form a contact hole reaching the drain interconnection, and forming a pixel electrode on the second insulating film to connect to the drain interconnection. Meanwhile, a holding capacitance is formed by the upper light-shielding film, the second insulating film and the pixel electrode.

1. Field of the Invention
The present invention relates to a semiconductor device having a circuit structured with thin film transistors (hereinafter, referred to as TFTs) and to a method for manufacturing the same. Particularly, the invention relates to an electro-optical device represented by the liquid crystal display panel and an electronic appliance mounted with such an electro-optical device as a part. Incidentally, in this description, the semiconductor device refers to the devices in general capable of functioning by the utilization of a semiconductor characteristic, i.e. an electro-optical device, a semiconductor circuit and an electronic appliance, in any, are fallen under a semiconductor device.
2. Description of the Prior Art
Recently, development has been proceeded for semiconductor devices having TFTs structured by using a thin film (thickness: approximately several to several hundred nm) formed on a substrate having an insulating surface to have a large-area integrated circuit forming TFTs. There is known an active-matrix liquid crystal display device as a representative example. In particular, the TFT using a crystalline silicon film in its active region is allowed to form various functional circuits because of its high electric-field mobility.
For example, the active-matrix liquid crystal display is formed, for each functional block, with a pixel circuit for image display, a shift resister circuit based on a CMOS circuit, such driver circuits for controlling the pixel circuit as a level shifter circuit, a buffer circuit and a sampling circuit, on one substrate.
The TFT has, at least, a semiconductor film, an insulating film such as a silicon oxide film or a silicon oxide nitride film, an interconnections of various metal materials or the like, and a pixel electrode. The interconnections include a source interconnection and a gate interconnection (including a gate electrode). The source interconnection and the source electrode connected to the source region, in many cases, are connected through the other interconnection.
Meanwhile, of among the active-matrix liquid crystal displays, the liquid crystal projectors using small-sized liquid crystal panels have being spread at a rapid pace to broaden the field of use. Due to this, there are demands for convenience. Development has being continued in order to advance size reduction, brightness increase, definition enhancement and price reduction.
The active-matrix liquid crystal display, used in a liquid crystal projector or electronic apparatus display, has a pixel region structured with several million pixels. Each pixel is formed with a TFT, and the TFT of each pixel has a pixel electrode. A counter electrode is provided on the counter substrate sandwiching a liquid crystal, to form a kind of capacitor having a liquid crystal as a dielectric. The potential to be applied to each pixel is controlled under TFT switching function to control the charge to the capacitor. Thus, the liquid crystal is driven to control the amount of transmission light thereby displaying images.
Because the capacitor gradually decreases in its capacitance due to current leakage, it forms a cause to vary the amount of light transmission and hence decrease the contrast in image display. For this reason, in the conventional, there has been provided a capacitance interconnection to provide, in parallel, a capacitor (holding capacitance) separately from the capacitor having a liquid crystal as a dielectric. The holding capacitance serves to supplement a capacitance lost by the capacitor having a liquid crystal as a dielectric.
However, when trying to form, in the pixel region, a holding capacitance using a capacitance interconnection and secure a sufficient capacitance, the opening ratio must be sacrificed. Particularly, it is to be fully expected that pixel size reduction be continued for the small-sized high-definition liquid crystal display as used in the liquid crystal projector, as long as definition enhancement is sought together with size reduction. For example, in order to realize display with definition as high as XGA (1024×768 pixels) on a liquid crystal display of a diagonal 0.7-inch type, each pixel has an area of as small as 14 μm×14 μm. Meanwhile, even in the case of providing a contact hole with an area of 1-μm square, the contact must be secured with an area of 3-μm square by extending one side at least by 1-μm each if considering a problem with coverage or the like. In the case of 14 μm on one side of one pixel, when a 3-μm-square contact is formed one, the opening ratio is lowered at least 4.6%. The number of contacts is of a significantly important problem amid the continuing pixel size reduction.
At present, brightness increase is coped with by increasing the opening ratio while definition enhancement is by increasing the number of pixels. However, amid continuing pixel size reduction, there is an extremely difficult problem in simultaneously satisfying the improvement in opening ratio and the increase in the number of pixels while designing a pixel structure with a sufficient capacitance secured. When trying to realize such a pixel structure, the number of processes naturally increases to make the process complicate. This results in a problem of worsened yield and semiconductor-device manufacture cost increase.
Meanwhile, there are cases that light leak current increases due to the light coming at a surface of a substrate not formed with TFTs of a light-transmission liquid crystal display or the light incident upon a top surface and irregularly reflected in the substrate, thus increasing an off-current (drain current flowing in a TFT off-state). The increase in leak current requires an increase of holding capacitance for compensation, causing a problem of lowering in opening ratio in the pixel region.
The present invention is an art for resolving the foregoing problem, and it is a problem to realize, by a reduced number of processes as compared to the conventional in respect of the structure of TFT and holding capacitance, a reliable active-matrix liquid crystal display device having a high opening ratio to make a display with definition. Meanwhile, it is a problem to realize high-definition image display even in a liquid crystal display device designed with a pixel size as small as ten and several μm square and in an electronic apparatus using, in a display part, such liquid crystal display device.

Semiconductor device and method for manufacturing the same

Semiconductor Energy Laboratory Co., Ltd.


In a method and apparatus for severing roots of bean sprouts, a severing table has a plurality of ridges formed at predetermined intervals and extending in parallel with a direction in which a cutter blade is moved. Each ridge is formed with a number of severing slits each of which has such a width that a root of a bean sprout falls into each severing slit. The bean sprouts are continuously supplied onto the severing table while a cutter blade is moved along an upper face of the severing table and water is being sprinkled over the severing table so that roots of the bean sprouts on the severing table flow into the severing slits. The roots of the bean sprouts fallen in the severing slits are severed by the cutter blade. The bean sprouts from which the roots have been severed are conveyed out of the severing table with movement of the cutter blade.

1. Field of the Invention
The present invention relates to a method and apparatus for severing roots of bean sprouts.
2. Description of the Related Art
Roots of bean sprouts harvested are typically cut off for improvement in their appearances and resultant increase in the commodity quality before the bean sprouts are bagged to be shipped. The inventor developed apparatus for severing roots of bean sprouts as disclosed in U.S. Pat. Nos. 6,346,288 and 6,379,732, in order to automate cutting off bean sprouts. In these apparatus, bean sprouts are supplied onto a flat severing table and water is sprinkled onto the severing table so that while a cutter blade is moved along an upper side of the severing table having a number of severing slits each of which has such a width that a root of a bean sprout falls into each severing slit. Alternatively, air is caused to blow from above the severing table so that a flow of air flowing downward through the severing slits is produced to cause the roots of the bean sprouts on the severing table to fall into the severing slits. The roots of the bean sprouts fallen in the severing slits are severed by the cutter blade.
The inventor has found the following problem in the course of severing roots of a number of bean sprouts using the above-mentioned severing apparatus. The roots of bean sprouts are generally strong. Accordingly, only distal end side slender portions of the bean sprout roots fall into the severing slits just when water is sprinkled onto or air is caused to blow onto the bean sprouts from above. Thick portions of the bean sprout roots in the vicinity of sprouts are hard to bend and to urge into the severing slits. Furthermore, when the bean sprouts on the severing table are scraped up by the cutter blade to be stacked, the bean sprouts of an upper layer of the pile are hard to urge into the severing slits and accordingly cannot be severed. As a result, since the number of bean sprouts whose distal end slender portions of the roots have been severed is increased, it is difficult to sever all roots of bean sprouts efficiently and cleanly.

Method and apparatus for severing root of bean sprout


A method to detect application spoofing in a mixed use avionics display by indicating when a mixed use avionics display is displaying information from a non-certified source. The method comprises providing an avionics display having a display area that is capable of displaying information from a non-certified source. A data connection is established between the non-certified source and the avionics display. Information is provided from the non-certified source to the avionics display through the data connection. The information from the non-certified source is then displayed on the display area so that less than the entire display area is used in displaying the information. The displaying of information from the non-certified source on less than the entire display area gives a visual indication that the information being displayed on the avionics display is from a non-certified source and susceptible to interference by a remote party and possible application spoofing.

Airlines rely upon flight manuals, procedural manuals, and other manuals in the operation of its aircraft. These manuals are continually being revised, modified and supplemented by the airlines to maintain current standards for operation of the aircraft. These manuals are carried on the aircraft in paper form and are quite extensive in size and weight. The various manuals that are used in operating aircraft can weigh 100 pounds or more. Every pound of materials carried by an aircraft increases fuel consumption and the cost to operate the aircraft. Airlines are constantly looking for ways to reduce their operating costs and therefore it is desirable to minimize the weight that must be carried by the aircraft.
In an effort to reduce the weight of these manuals, airlines are increasingly relying upon the use of these manuals in electronic format. The manuals are converted into computer applications that are modifiable by the airlines, hereinafter referred to as Airline Modifiable Software (AMS). The AMS must receive approval from the regulatory agencies that oversee aircraft operation, such as the Federal Aviation Administration. These regulatory agencies approve the AMS for use in lieu of the paper manuals. In order to utilize the AMS, a display is required that can be viewed by the flight crew at various times during the operation of the aircraft.
The flight deck on an aircraft has numerous certified flight deck displays upon which the AMS could potentially be displayed. However, the AMS applications are not certified and are therefore not currently allowed to be displayed on a certified flight deck display. As a possible solution, an aircraft manufacturer could install additional certified displays on the flight deck that are dedicated to displaying the AMS. However, space is extremely limited on the flight deck and certified displays are expensive to build and have certified. Additionally, certified displays have been shown to not be cost effective when limited to non-essential functions, such as the AMS.
Another potential problem with using an existing certified flight deck display to display the AMS is that the AMS applications must be prevented from affecting the safe operation of the aircraft. AMS applications are increasingly expected to be provided by sources that are not in or on the flight deck. For example, AMS applications can be provided by an airline-controlled server which is installed on the airplane. However, the airline-controlled server may at times (during flight crew access or not) be connected to off board networks. These networks are open and therefore susceptible to malicious interference by remote parties that may go undetected. Because these networks are open, there is a possibility that a remote party could maliciously interfere with the safe operation of the aircraft by interfering with the displaying of the AMS on the existing certified display. For example, the malicious remote party could design an application that emulates or spoofs the certified display and have that application appear on the certified display with incorrect data instead of the AMS. The flight crew would think that the certified display was displaying the information for which the display is certified and believe that the inaccurate data is true and subsequently affect the safe operation of the aircraft.
Therefore, to limit the possibility of malicious interference by remote parties airlines have relied upon the use of carry-on personal electronic devices (PEDs), such as laptop computers, to run the AMS applications. The PED's could avoid the possibility of malicious interference by remote parties if the PED's were never connected to open networks. However, most PED's are at sometime connected to open networks and, therefore, exposed to malicious interference which may not be detected. The use of PEDs are also not without substantial drawbacks. As stated above, space is limited on a flight deck and the PEDs can interfere with the operation of the flight deck controls, particularly the control column. Additionally, the PEDs could present a hazard during turbulence in that the PEDs may injure a member of the flight crew or damage equipment. Furthermore, PEDs cannot be used during some phases of flight during which it may be desirable to have the AMS applications displayed. Finally, some PEDs will not be bright enough for sunlit conditions nor dim enough for nighttime use to facilitate efficient and comfortable use by members of the flight crew.
Therefore, it would be advantageous to an airline if it could use a certified flight deck display to display the AMS applications while preventing or at least detecting malicious interference by remote parties.

Method to detect application spoofing in mixed use avionics display


A connector includes a connector housing and a shield shell. A terminal electrically connected to an end part of a wire is arranged inside the connector housing. The connector housing includes an inserting portion to be inserted into a mounting hole provided in a conductive case for accommodating an inverter and an outer arrangement portion integral with the inserting portion and to be arranged outside the case. A case-side sealing member seals between the outer peripheral surface of the inserting portion and the inner peripheral surface of the mounting hole. The shield shell is electrically connected to the case and covers the outer periphery of the outer arrangement portion. The inserting portion includes a first intrusion suppressing groove continuously provided over the entire periphery of the inserting portion in a part of the outer peripheral surface of the inserting portion between the case-side sealing member and the outer arrangement portion.

Conventionally, some of connectors to be mounted on a case accommodating a device to be installed in a vehicle are provided with a shield shell for suppressing the radiation of electromagnetic noise to outside from the connector. Such a connector may be mounted in a mounting hole provided in the case, for example, as described in Patent Document 1. A connector described in Patent Document 1 includes a connector housing in which a terminal electrically connected to an end part of a wire is arranged. The connector housing includes an inserting portion to be inserted into a mounting hole and an outer arrangement portion integral with the inserting portion and to be arranged outside the case. The outer arrangement portion has the outer periphery thereof covered by a shield shell. The shield shell is electrically connected to the case by coming into contact with the case. A case-side sealing member for suppressing the intrusion of a liquid such as water into the case through a clearance between the outer peripheral surface of the inserting portion and the inner peripheral surface of the mounting hole is arranged between the outer peripheral surface of the inserting portion and the inner peripheral surface of the mounting hole. The case-side sealing member has an annular shape and is externally fit to the inserting portion.


The invention relates to a bed bug detection device (10) comprising a refuge (16) which elicits a taxis response from bed bugs and a non-trapping indicator surface (18), on which the bed bugs may leave indicators of their presence, such as faecal matter or cast skins. The refuge is positioned in close proximity to said non-trapping indicator surface such that the bed bugs can leave an indicator of their presence as they travel across the indicator surface on their way to or from the refuge. Preferably the non-trapping indicator surface takes the form of a skirt which surrounds a refuge made of corrugated paper. The invention also provides a passive method of detecting the presence of bed bugs without their capture by detecting the presence of indicators rather than the bed bugs per se.

Bed bugs (Cimex lectularius and Cimex hemipterus) are small insects that feed off the blood of humans and other warm-blooded hosts. Bed bugs usually spend daylight hours in dark enclosed sites and have a preference for crevices in fabric, wood and paper. The bed bugs create a micro-environment in which they live during the day. In recent years, there has been a world-wide increase in the prevalence of bed bugs.
Bed bugs are attracted to the heat and carbon dioxide given off by warm-blooded hosts, which make bedrooms, and especially mattresses and headboards, an ideal environment for them to take refuge. Bed bugs are known for being elusive, transient and mainly active at night, making their detection difficult. They may be transferred between locations on furniture, bags, clothes or people.
As personal injury litigation injury is on the rise, hotels, transport providers and many other service sectors are at risk of expensive court actions should a customer receive a bite from, or pick up, bed bugs. Therefore, there is a need, at least in hotel rooms, to easily identify whether a location is inhabited by bed bugs so that it can be treated.
The most common method of detection of bed bugs is by identifying the bites, which they inflict on the bed occupant. The bites inflict a dermatological reaction in humans, but this usually cannot be felt until some minutes or hours and in some cases days after the bug bites and the first indication of a bite usually comes from the desire to scratch the bite site. Generally, it shows up as either a raised red bump or a flat welt, often in groups of three or so following the line of a vein.
Clearly waiting for the bed bugs to bite has many disadvantages, for example the bites are very similar to mosquito bites and therefore difficult to identify. Detecting the bugs before they bit would be better. One method of detecting bed bugs is to have a readily available light source, such as a torch, and shining it on the bed during the night to try and catch any bed bugs that are active. A disadvantage of this is that movement of the person in the bed may alert the bed bugs and they can then scatter.
Another current method of detecting bed bugs is to use glue traps, often in conjunction with a heat pad and carbon dioxide source to attract the bugs. Such devices are expensive and require the use of an electrical source to keep the carbon dioxide source and heat pad running. This makes them unsuitable for use in hotel rooms due to the expense of the initial purchase and subsequent cost of running.
Using double-sided carpet tape as, effectively, another form of glue trap has been proposed. However, the bed bugs may find ways to avoid the tape and the tape is unsightly.
The worldwide increase in the prevalence of bed bugs, referred to earlier, is caused by reasons which need not be explored here. But it highlights the need for a solution to the problems they cause and this brief review of known attempts to detect and eliminate them (all of which are based around active capture) shows that there is no clear starting point—and indeed no satisfactory universal solution from which the problem may be tackled.

Insect monitoring device and method of detection


A fluorine-containing organic film having a relative dielectric constant of 4 or less is deposited on a semiconductor substrate using a material gas containing fluorocarbon as a main component in a reactor chamber of a plasma processing apparatus. During the deposition of the fluorine-containing organic film, a scavenger gas for scavenging fluorine constituting the fluorocarbon is mixed in the material gas. The proportion of the mixed scavenger gas in the material gas is changed to adjust the mechanical strength and relative dielectric constant of the fluorine-containing organic film.

The present invention relates to a semiconductor device that includes a fluorine-containing organic film having a low relative dielectric constant and a method for fabricating the same.
With recent remarkable progress in semiconductor process technology, finer semiconductor elements and metal interconnections with higher integration have been pursued. With this trend toward finer size and higher integration, signal delay at metal interconnections has come to greatly influence the operation speed of semiconductor integrated circuits.
In the above situation, desired is a technique of forming a fluorine-containing organic film (fluorocarbon film) that contains carbon atoms and fluorine atoms as main components and has a relative dielectric constant lower than that of an inorganic film such as a SiO2 film or a SiOF film.
A fluorine-containing organic film has a relative dielectric constant of about 2, which is lower than the relative dielectric constant of a SiOF film (about 3.5 to about 3.8). Accordingly, by depositing such a fluorine-containing organic film between metal interconnections or on the top surfaces of metal interconnections, signal delay at the metal interconnections can be reduced.
However, the fluorine-containing organic film deposited using a material gas containing fluorine described above is disadvantageously poor in denseness and thus insufficient in mechanical strength, heat resistance, chemical resistance, and the like.
In order to solve the above problem, Japanese Laid-Open Patent Publication No. 10-199976 proposes a method for densifying a fluorine-containing organic film to improve mechanical strength, oxidation resistance, and heat resistance in the following manner. A copolymer of a polytetrafluoroethylene resin or a cyclic fluorine resin and siloxane is dissolved in a fluorocarbon solvent. The resultant solution is applied to a substrate while rotating, to obtain a fluorine-containing organic film. The resultant fluorine-containing organic film is then subjected to annealing where the film is kept in an atmosphere of an inert gas such as nitrogen gas at a temperature of 400xc2x0 C. for 30 minutes.
By the annealing of the fluorine-containing organic film, the film is densified and thus the mechanical strength improves as described above. However, since fluorine atoms in the film are volatilized by the annealing, the relative dielectric constant of the film increases. That is, if no annealing is performed, the relative dielectric constant is low, but the mechanical strength is poor. If annealing is performed, the mechanical strength improves, but the relative dielectric constant becomes high. In other words, reduction in relative dielectric constant and improvement in mechanical strength are completely in the trade-off relationship where selection of either one only is allowed.
In view of the above, the object of the present invention is allowing control of the amount of fluorine atoms contained in a fluorine-containing organic film to balance reduction in relative dielectric constant with improvement in mechanical strength.
In order to attain the above object, the first method for fabricating a semiconductor device of the present invention includes the step of: depositing a fluorine-containing organic film having a relative dielectric constant of 4 or less on a semiconductor substrate using a material gas containing fluorocarbon as a main component in a reactor chamber of a plasma processing apparatus, wherein in the deposition of a fluorine-containing organic film, a scavenger gas for scavenging fluorine constituting the fluorocarbon is mixed in the material gas, and the proportion of the mixed scavenger gas in the material gas is changed to adjust the mechanical strength and relative dielectric constant of the fluorine-containing organic film.
According to the first method for fabricating a semiconductor device, the mechanical strength and relative dielectric constant of the fluorine-containing organic film are adjusted by changing the proportion of the scavenger gas mixed in the material gas. Therefore, it is possible to reduce the relative dielectric constant by relatively increasing the amount of fluorine atoms in the film for a fluorine-containing organic film giving high priority to reduction in relative dielectric constant. Contrarily, it is possible to increase the mechanical strength by relatively decreasing the amount of fluorine atoms in the film for a fluorine-containing organic film giving high priority to improvement in mechanical strength. In other words, by changing the proportion of the scavenger gas mixed in the material gas, reduction in relative dielectric constant and improvement in mechanical strength are balanced.
The second method for fabricating a semiconductor device of the present invention includes the steps of: depositing a first fluorine-containing organic film having a relative dielectric constant of 4 or less on a semiconductor substrate using a first material gas in a reactor chamber of a plasma processing apparatus, the first material gas containing fluorocarbon gas mixed with a relatively small amount of a scavenger gas for scavenging fluorine constituting the fluorocarbon; and depositing a second fluorine-containing organic film on the first fluorine-containing organic film using a second material gas in the same reactor chamber, the second fluorine-containing organic film being superior in mechanical strength to and higher in relative dielectric constant than the first fluorine-containing organic film, the second material containing the fluorocarbon gas mixed with a relatively large amount of the scavenger gas.
According to the second method for fabricating a semiconductor device, the first fluorine-containing organic film is deposited using the first material gas containing a scavenger gas for scavenging fluorine constituting the fluorocarbon in a relatively low mixture proportion, while the second fluorine-containing organic film is deposited using the second material gas containing the scavenger gas in a relatively high mixture proportion. Therefore, the first fluorine-containing organic film has a relatively low mechanical strength but has a relatively low relative dielectric constant, while the second fluorine-containing organic film has a relatively high relative dielectric constant but has a relatively high mechanical strength. In this way, by only changing the mixture proportion of the scavenger gas, it is possible to form the first fluorine-containing organic film having a relatively low relative dielectric constant and the second fluorine-containing organic film having a relatively high mechanical strength.
In the first or second fabrication method, the scavenger gas is preferably CO gas. This ensures scavenging of fluorine constituting the fluorocarbon.
In the first or second fabrication method, the fluorocarbon is preferably C5F8, C3F6, or C4F6.
Using the above fluorocarbon, the number of free fluorine atoms in the deposited fluorine-containing organic film decreases. This densifies the fluorine-containing organic film and also improves the adhesion thereof. In addition, C5F8 gas, C3F6 gas, and C4F6 gas less easily cause global warming compared with other perfluorocarbon gases.
In the second fabrication method, the first fluorine-containing organic film is preferably deposited between a plurality of metal interconnections formed on the semiconductor substrate.
With the above construction, since the relative dielectric constant of the first fluorine-containing organic film is low, the capacitance at the metal interconnections is small. In addition, the second fluorine-containing organic film deposited on the first fluorine-containing organic film has a high mechanical strength. Thus, compatibility between reduction in capacitance at the metal interconnection structure and improvement in mechanical strength is attained.
In the second fabrication method, the first material gas may not contain the scavenger gas. This ensures the reduction in the relative dielectric constant of the first fluorine-containing organic film.
Preferably, the second fabrication method further includes the step of: densifying the second fluorine-containing organic film by exposing the second fluorine-containing organic film to plasma of a rare gas in the same reactor chamber.
By the above step, the mechanical strength of the second fluorine-containing organic film further increases, and the heat resistance and chemical resistance thereof further improve.
The semiconductor device of the present invention includes: a plurality of metal interconnections formed on a semiconductor substrate; a first fluorine-containing organic film deposited at least between the plurality of metal interconnections; and a second fluorine-containing organic film deposited on the first fluorine-containing organic film, wherein the amount of fluorine atoms contained in the second fluorine-containing organic film is smaller than the amount of fluorine atoms contained in the first fluorine-containing organic film.
According to the semiconductor device of the present invention, the first fluorine-containing organic film has a relatively low mechanical strength but has a relatively low relative dielectric constant, while the second fluorine-containing organic film has a relatively high relative dielectric constant but has a relatively high mechanical strength. Thus, compatibility between reduction in capacitance at the metal interconnections and improvement in mechanical strength is attained.

Semiconductor device and method for fabricating the same

Matsushita Electric Industrial Co., Ltd.


Systems for electrically isolating portions of wafers are provided. A representative system includes a first wafer and a first conductor formed at least partially through the first wafer. A first conductor insulating layer is formed at least partially through the first wafer. The first conductor insulating layer engages the first conductor and is disposed between the first conductor and material of the first wafer. A first outer insulating layer also is provided that is formed at least partially through the first wafer. The first outer insulating layer is spaced from the first conductor insulating layer. Both the first conductor insulating layer and the first outer insulating layer are formed of dielectric material. Methods also are provided.

1. Field of the Invention
The present invention generally relates to semiconductors. More specifically, the invention relates to systems and methods pertaining to semiconductors that incorporate one or more electrically isolated portions.
2. Description of the Related Art
Semiconductor wafers oftentimes are arranged in an overlying relationship with each other and are bonded together to form a wafer stack. In order to facilitate communication of processing of one wafer of such a wafer stack with processing of another wafer, various interconnecting structures may be used. For example, wires can be used to interconnect components of the various wafers so that the components can electrically communicate with each other. In other wafer stacks, conductor vias can be used. A representative example of such a via is depicted in FIG. 1.
As shown in FIG. 1, wafer 100 includes a via structure 102 that is formed through the material of the wafer. Via structure 102 includes an insulator ring 104 that is formed about a conductor 106. Via structure 102 permits the propagation of low voltage signals from one side of wafer 100 to the other side. More specifically, such a signal can be propagated from one side of the wafer to the other through conductor 106. Unfortunately, via structure 102 tends to breakdown or short when relatively large potential differences exist between the conductor 106 and the substrate 108. Thus, it can be appreciated that there is a need for improved systems and methods that address these and/or other shortcomings of the prior art.

Methods for electrically isolating portions of wafers

Hewlett-Packard Development Company, L.P.


A heat recovery system for a turbomachine system includes a heat removal system and a refrigeration system. The heat removal system is fluidly connected to at least one component of the turbomachine system. The heat removal system passes a cooling fluid through the at least one component to absorb heat. The refrigeration system is operatively connected to the heat removal system. The refrigeration system extracts the heat from the cooling fluid passing through the at least one component of the turbomachine system to produce a cooling effect.

Exemplary embodiments of the present invention relate to the art of heat recovery systems and, more particularly, to a heat recovery system for a turbomachine system.
In operation, generators, particularly those employed in connection with gas and steam turbine combined systems, produce a large amount of heat. In order to reduce the amount of heat, most generators are provided with cooling systems. In some instances, air cooling is sufficient. In other cases, particularly in larger generator systems, water is employed as a cooling medium. More specifically, water is directed through, for example stator windings, to capture and guide heat away from the generator. The water is then passed through a cooling tower to remove absorbed heat before being again passed through the generator. While effective, the heat captured from the water is lost, thus resulting in a lower overall efficiency for the power plant. Furthermore, the additional work required to pass the water though the cooling tower further contributes to power plant inefficiencies.

Power plant heat recovery system having heat removal and refrigerator systems


The invention relates to compounds of formula (I) having pharmacological activity towards the sigma receptor, to processes of preparation of such compounds, to pharmaceutical compositions comprising them, and to their use for the treatment and or prophylaxis of a disease in which the sigma receptor is involved.

The search for new therapeutic agents has been greatly aided in recent years by better understanding of the structure of proteins and other biomolecules associated with target diseases. One important class of these proteins is the sigma (σ) receptor, a cell surface receptor of the central nervous system (CNS) which may be related to the dysphoric, hallucinogenic and cardiac stimulant effects of opioids. From studies of the biology and function of sigma receptors, evidence has been presented that sigma receptor ligands may be useful in the treatment of psychosis and movement disorders such as dystonia and tardive dyskinesia, and motor disturbances associated with Huntington's chorea or Tourette's syndrome and in Parkinson's disease (Walker, J. M. et al, Pharmacological Reviews, 1990, 42, 355). It has been reported that the known sigma receptor ligand rimcazole clinically shows effects in the treatment of psychosis (Snyder, S. H., Largent, B. L. J. Neuropsychiatry 1989, 1, 7). The sigma binding sites have preferential affinity for the dextrorotatory isomers of certain opiate benzomorphans, such as (+)SKF 10047, (+)cyclazocine, and (+)pentazocine and also for some narcoleptics such as haloperidol.
The sigma receptor has at least two subtypes, which may be discriminated by stereoselective isomers of these pharmacoactive drugs. SKF 10047 has nanomolar affinity for the sigma 1 (σ-1) site, and has micromolar affinity for the sigma (σ-2) site. Haloperidol has similar affinities for both subtypes. Endogenous sigma ligands are not known, although progesterone has been suggested to be one of them. Possible sigma-site-mediated drug effects include modulation of glutamate receptor function, neurotransmitter response, neuroprotection, behavior, and cognition (Quirion, R. et al. Trends Pharmacol. Sci., 1992, 13:85-86). Most studies have implied that sigma binding sites (receptors) are plasmalemmal elements of the signal transduction cascade. Drugs reported to be selective sigma ligands have been evaluated as antipsychotics (Hanner, M. et al. Proc. Natl. Acad. Sci., 1996, 93:8072-8077). The existence of sigma receptors in the CNS, immune and endocrine systems have suggested a likelihood that it may serve as link between the three systems.
In view of the potential therapeutic applications of agonists or antagonists of the sigma receptor, a great effort has been directed to find selective ligands. Thus, the prior art discloses different sigma receptor ligands.
International Patent Application WO 91/09594 generically describes a broad class of sigma receptor ligands some of which are 4-phenylpiperidine, -tetrahydro-pyridine or -piperazine compounds having an optionally substituted aryl or heteroaryl, alkyl, alkenyl, alkynyl, alkoxy or alkoxyalkyl substituent on the ring N-atom. The terms aryl and heteroaryl are defined by mention of a number of such substituents.
European patent application EP 0 414 289 A1 generically discloses a class of 1,2,3,4-tetrahydro-spiro[naphthalene-1,4′-piperidine] and 1,4-dihydro-spiro[naphthalene-1,4′-piperidine] derivatives substituted at the piperidine N-atom with a hydrocarbon group alleged to have selective sigma receptor antagonistic activity. The term hydrocarbon, as defined in said patent, covers all possible straight chained, cyclic, heterocyclic, etc. groups. However, only compounds having benzyl, phenethyl, cycloalkylmethyl, furyl- or thienylmethyl or lower alkyl or alkenyl as the hydrocarbon substituent at the piperidine nitrogen atom are specifically disclosed. The compounds are stated to displace tritiated di-tolyl guanidine (DTG) from sigma sites with potencies better than 200 nM. 1-benzyl-1,2,3,4-tetrahydro-spiro[naphthalene-1,4′-piperidine] is mentioned as a particularly preferred compound.
European patent application EP 0 445 974 A2 generically describes the corresponding spiro[indane-1,4′-piperidine] and spiro[benzocycloheptene-5,4′-piperidine] derivatives. Again the compounds are only stated to displace tritiated di-tolyl guanidine (DTG) from sigma sites with potencies better than 200 nM.
European patent Application EP0 431 943 A relates to a further extremely broad class of spiropiperidine compounds substituted at the piperidine N-atom and claimed to be useful as antiarrhythmics and for impaired cardiac pump function. The said application exemplifies several compounds, the majority of which contain an oxo and/or a sulfonylamino substituent in the spiro cyclic ring system. Of the remainder compounds, the main part has another polar substituent attached to the spiro nucleus and/or they have some polar substituents in the substituent on the piperidine N-atom. No suggestion or indication of effect of the compounds on the sigma receptor is given.
Patent applications EP 518 805 A and WO 02/102387 describe sigma receptor ligands having piperidine or spiropiperidine structures.
With regard to the chemical structure of the compounds described in the present patent application, there are some documents in the prior art which disclose pyrazole derivatives characterized, among other things, for being substituted by amino alkoxy groups in different positions of the pyrazole group.
U.S. Pat. No. 4,337,263 discloses 1-aryl-4-arylsulphonyl-3-amino propoxy-1H-pyrazoles, wherein the amino group can be constituted by an N-cycle group as morpholine, piperidine or pyrrolidine group. They are used as hypolipemiant or hypocholesteroleminant agents.
Patent FR 2301250 describes similar compounds as those mentioned above, such as 1,4-diaryl-3-aminoalcoxy pyrazoles, wherein the amino group comprises pyrrolidine, piperidine, hydroxypiperidine, morpholine or piperazine derivatives.
Patent Application US2003/0144309 refers to pyrazoles with their 3 position substituted by a dimethylaminoethoxy group and present in their 4 position a pirimidine group. They are used as inhibitors of JNK3, Lck or Src kinase activity.
International patent Application WO 02/092573 describes substituted pirazole compounds as inhibitors of SRC and other protein kinases.
International patent Application WO 2004/017961 discloses pyrazol compounds wherein the 3 position is substituted by an alcoxy group directly bounded to a cyclic amide, which are used for therapeutically treating and/or preventing a sex hormone related condition in a patient.
U.S. Pat. No. 6,492,529 describes pyrazole derivatives which are used for the treatment of inflammatory diseases. These compounds present in the 5 position a urea group, linked in some cases to a morpholine ethoxy group.
International patent Application WO 04/016592 refers to pyrazole compounds for inhibiting protein prenylation which comprises in the 5 position, among others, an alcoxy group directly bonded to a cyclic amide.
However, none of these documents suggests the effect of these compounds on the sigma receptor.
There is still a need to find compounds that have pharmacological activity towards the sigma receptor, being both effective and selective, and having good "drugability" properties, i.e. good pharmaceutical properties related to administration, distribution, metabolism and excretion.


A mass spectrometer is disclosed. The mass spectrometer may include an ion trap configured to trap and analyze an ionized sample. A first aperture may be provided having a first diameter, and a second aperture may be provided having a second diameter. The first aperture may be configured to receive electrons for the purpose of ionizing sample ions within the ion trap. The second aperture may be configured to receive photons for the purpose of ionizing sample ions within the ion trap.

Mass spectrometers are instruments used to analyze the mass and abundance of various chemical components in a sample. Mass spectrometers work by ionizing the molecules of a chemical sample, separating the resulting ions according to their mass-charge ratios (m/z), and then measuring the number of ions at each m/z value. The resulting spectrum reveals the relative amounts of the various chemical components in the sample.
One type of mass analyzer used for mass spectrometry is called a quadrupole ion trap. Quadrupole ion traps take several forms, including three-dimensional ion traps, linear ion traps, and cylindrical ion traps. The operation in all cases, however, remains essentially the same. Direct current (DC) and time-varying radio frequency (RF) electric signals are applied to the electrodes to create electric fields within the ion trap. These fields trap ions within the central volume of the ion trap. Then, by manipulating the amplitude and/or frequency of the electric fields, ions are selectively ejected from the ion trap in accordance with their m/z. A detector records the number of ejected ions at each rink as they arrive. Regardless of the particular technology of mass spectrometer used, before sample molecules can be analyzed they must be ionized by one of various methods.
Electron ionization (EI) is one common method for generating sample ions. In EI, electrons are typically produced through a process called thermionic emission from a filement. Thermionic emission occurs when the kinetic energy of a charge carrier, in this case electrons, overcomes the work function of the conductor. In a vacuum chamber of a gas analyzer, where there is little gas or air to conduct heat from or react with a filament, a current through the filament quickly heats it until it emits electrons. The electrons are accelerated, usually with a set of electron optics, towards the sample, which may be contained within a mass analyzer (e.g., an ion trap). As the electrons travel through the gaseous sample, the electrons interact with, fragment, and ionize molecules in the sample. The charged particles can then be transported and analyzed using additional electric fields.
EI uses relatively energetic electrons with energies of around 70 electron volts to ionize sample molecules, and as such can sometimes cause weaker molecules to fragment into smaller ions. For this reason energetic electrons are sometimes referred to as a "hard" ionization source. Fragmentation can be beneficial in cases where one wishes to learn more about the parent ion by analyzing the fragment or "daughter" ions. In cases where fragmentation is not desired (e.g., it is desirable to know the mass of the parent ion), a softer ionization technique may be appropriate.
One such soft ionization technique is photoionization (PI). In PI, a light source emits photons, generally in the ultraviolet wavelength range, to provide sufficient energy to eject electrons from molecules in the chemical sample, thereby ionizing them. The photons in PI have lower energy than the electrons in EI, typically 5-10 electron volts as opposed to the 70 electron volts typical of EI. As such, PI generally allows sample compounds to remain intact. Broadly speaking, PI can be accomplished by two different techniques: single-photon ionization, and multi-photon ionization. Single-photon PI occurs when the PI source produces photons that individually have sufficient energy to ionize molecules. This usually corresponds to about 10.6 electron volts, or 110-130 nm wavelength. In multi-photon PI, the photons have less energy, perhaps only 5 electron volts, or 240-260 nm wavelength, and therefore multiple photon-molecule interactions are required to ionize the molecule.
Single-photon PI generally requires a source such as a plasma lamp in the ultraviolet range. Traditional ultraviolet light sources are generally large compared to the dimensions of an ion trap, and may require the source to be located away from the trapping region. As a result, ions must be created outside of the ion trap and transported into the ion trap via the use of electric fields or fluid flow. However, creating ions outside of the ion trap may result in reduced sensitivity of the mass spectrometer, and the electron optics required to transport the ions may add additional complexity to the instrument. Also, some architectures used for mass analyzers that lend themselves to miniaturization, for example ion traps, may not be effective at efficiently trapping ions generated from an external source. In addition, the extra ionization chamber requires more space and larger vacuum pumps to evacuate, making it potentially unsuitable for applications where size and power consumption are an issue.
Laser diodes are small enough to provide an ultraviolet light source directly into an ion trap; however, they are limited to a wavelength of 248 nm, which corresponds to about 5 electron volts. This energy is insufficient for single-photon PI. Multi-photon PI is possible, however, with appropriate pulsing of laser diodes.
Embodiments of the disclosure described herein may overcome at least some of the disadvantages described above.

Ionization within ion trap using photoionization and electron ionization


This invention relates to a process for preparing alditol acetals, such as dibenzylidene sorbitols, monobenzylidene sorbitols, and the like, through the reaction of unsubstituted or substituted benzaldehydes with alditols (such as sorbitol, xylitol, and ribitol) in the presence of a mineral acid and at least one surfactant having at least one pendant group of 6 carbon chains in length. Such a reaction provides a cost-effective, relatively safe procedure that provides excellent high yields of alditol acetal product. Furthermore, such a specific reaction is also the best known procedure for the production of certain compounds which can be easily separated from other formed isomers. Additionally, such a procedure facilitates the production of certain asymmetric alditol acetal compounds and compositions in acceptable yields as well. Such alditol acetals are useful as nucleating and clarifying agents for polyolefin formulations and articles, as one example.

This invention relates to a process for preparing alditol acetals, such as dibenzylidene sorbitols, monobenzylidene sorbitols, and the like, through the reaction of unsubstituted or substituted benzaldehydes with alditols (such as sorbitol, xylitol, and ribitol) in the presence of a mineral acid and at least one surfactant having at least one pendant group of 6 carbon chains in length. Such a reaction provides a cost-effective, relatively safe procedure that provides excellent high yields of alditol acetal products, particularly those which have heretofore not been readily available due to processing limitations, such products including bis(5-indanylidene)sorbitol. Furthermore, such a specific reaction is also the best known procedure for the production of certain compounds which can be easily separated from other formed isomers. Additionally, such a procedure facilitates the production of certain asymmetric alditol acetal compounds and compositions in acceptable yields as well. Such alditol acetals are useful as nucleating and clarifying agents for polyolefin formulations and articles, as one example.
All U.S. Patent documents and other publication discussed below are herein entirely incorporated by reference.
Dibenzylidene sorbitol (xe2x80x9cDBSxe2x80x9d), substituted DBS""s, such as can be made with alkyl substituted aromatic aldehydes, and related acetals have found utility as nucleating agents, clarifying agents, gelling agents, processing aids, and strength modifiers in polyolefin resins, polyester resins, deodorant, and antiperspirant compositions; hydrocarbon fuels; waste liquids, especially those containing organic impurities; and paint.
Alditol acetals, such as DBS derivative compounds, are typically prepared by the condensation reaction of an aromatic aldehyde with a polyhydric alcohol, for example, without limitation, sorbitol, xylitol, ribitol, and the like. For DBS structures, such reactions involve two moles of the aldehyde and one mole of the alcohol. Examples of suitable processes may be found in Uchiyama, U.S. Pat. No. 4,267,110, Murai et al., U.S. Pat. No. 3,721,682; Murai et al., U.S. Pat. No. 4,429,140; Machell, U.S. Pat. No. 4,562,265; Kobayashi et al., U.S. Pat. No. 4,902,807; Salome et al., U.S. Pat. No. 5,023,354; and Scrivens et al., U.S. Pat. No. 5,731,474.
Unfortunately, these previous reaction procedures all suffer significant drawbacks for utilization within a greater breadth of reactions. The first procedure taught was by Uchiyarna solely for the production of limited DBS compounds of the unsubstituted benzaldehyde type. The lack of versatility of such a procedure has severely limited its implementation within different DBS compound producing methods. Solvent-based systems have been developed for higher yield and greater versatility of DBS formation, for instance, within the Murai et al., Scrivens et al, and Kobayashi et al. patents, which all concerned reactions for the production of un-, mono-, or di-substituted dibenzylidene sorbitols. Although these reactions are highly effective in producing high yield, high purity DBS compounds, the solvents needed are expensive and the energy required to effectuate necessary mixing and high temperatures is also expensive. In an effort to reduce such solvent costs, low temperature low temperature aqueous procedures have been developed, such as in the Machell and Salome et al. patents. Machell requires the utilization of a mineral acid as the catalyst alone for acetalization; Salome et al. specifically exclude any mineral acids from their procedure and instead rely solely upon the presence of relatively large amounts of arylsulfonic acid catalysts to effectuate acetalization of the benzaldehyde and alditol components. Machell thus requires large amounts of mineral acids whereas Salome et al. require expensive arylsulfonic compounds (such as para-toluenesulfonic acid, naphththalene sulfonic acid, and the like). More importantly, however, it has now been found that there are key problems with both types of procedures which require improvement. For instance, the previous uses of acid alone, as in Machell, or with arylsulfonic acids alone, as in Salome et al., as acetalization catalysts have proven very difficult for a number of reasons. The Machell method of acid alone has suffered from a lack of effectiveness in producing highly-substituted DBS derivatives, apparently, and without intending to be limited to any specific scientific theory, from the lack of contacting a sufficient amount of catalyst with the reactants themselves to permit combination and thus acetalization. In the past, such mineral acids have proven to be excellent catalysts alone for un- or certain minimally-substituted benzaldehydes (e.g., p-methylbenzaldehyde). Apparently, di-substituted benzaldehydes and above are more hydrophobic and thus do not solubilize well within aqueous acid formulations. In such a situation, the catalysis of di-substituted (or higher)benzaldehydes with alditol is nearly nonexistent due to a lack of effective contact between all three components (e.g., acid, benzaldehyde, and alditol). Benzaldehyde and p-methylbenzaldehyde, on the other hand, are much more soluble within such an aqueous acid formulation and thus more easily contact the acid catalyst, thereby permitting a more effective acetalization of the alditol for very high yields. Thus, from a versatility standpoint, the use of mineral acids alone, although the best catalyst for acetalization procedures, does not effectively contact with certain reactants due to solubility considerations. The Salome et al. method requires a very large amount of very expensive arylsulfonic compounds (Salome et al. require a molar ratio of benzaldehyde to arylsulfonic acid of at least 1:0.6) as catalysts alone within the reaction mixture. Although such large amounts of arylsulfonic acid catalyst have proven to be effective for certain reactions of benzaldehydes with alditols, a combination of both costs and lack of versatility has been problematic from a large-scale industrial production standpoint. The arylsulfonic acids alone either do not contact sufficiently (as with p-toluenesulfonic acid) or are not strong enough acid catalysts alone to provide the needed reactivity for greater versatility with different benzaldehyde reactants at lower levels at concentration within the reaction mixture. Thus, the cost of such arylsulfonic acids, being relatively high and extremely high in comparison with the more effective mineral acids, pose considerable economic problems for the user.
Clearly, the utilization of less expensive mineral acids, which are better catalysts at lower amounts, is a preferred method from a cost perspective; however, the lack of versatility has been a hindrance to widespread use and effectiveness of such a method. The yield offered by both teachings is acceptable, however the versatility of producing large variations of different DBS compounds is questionable. There has been a need to provide a procedure which permits production of not only standard p-methyldibenzylidene sorbitol (MDBS), 3,4-dimethyldibenzylidene sorbitol (DMDBS), and dibenzylidene sorbitol (DBS), but other compounds which heretofore have been impossible to produce either at all or at least in any acceptable yield and/or purity. As a few examples, 1,3:2,4-bis(5-indanylidene)sorbitol has been unavailable as a product due to the lack of production of such a compound in any yield acceptable on an industrial scale or without the need for using excess amounts of the reactive benzaldehyde. Such a compound is known to provide excellent clarifying and nucleating benefits within polypropylene formulations, but, again, has not been readily utilized in such a market because of the lack of effective production methods for large-scale reliable availability. Also, other types of compounds, such as certain symmetrical compounds [e.g., 1,3:2,4-bis(3-ethyl-4-methylbenzylidene)sorbitol and 1,3:2,4-bis(3,4-diethylbenzylidene) sorbitol] have not been available as pure product due to the presence of isomers and/or reaction mixture additives which could not be readily removed or separated from the desired compounds. With the lack of versatility, cost problems, potential corrosiveness, or all three, the above-listed and discussed methods have proven ineffective in providing needed advances in DBS production technology. Without any further teachings or fair suggestions, expansions into other DBS compound areas to develop alternative and more specialized polyolefin nucleation and/or clarification markets and products has been hampered. Hence, there is a need to develop a procedure to facilitate high yield, reliable, versatile, cost-effective, and safe production of both standard and novel alditol acetal derivative compounds. To date, again, although some processes do exist permitting production of limited types of DBS compounds, or provide some versatility, but at a rather large cost economically, there simply is no effective alternative to expand the production capabilities of a wide array of such alditol acetal derivatives.
Therefore, an object of the invention is to provide a process a highly versatile process for producing high yields of alditol acetal derivative compounds, most notably, without limitation symmetrical and asymmetrical DBS compounds. A further object of the invention is to provide a highly effective manner of producing such compounds which heretofore could not be produced in high yields without incurring potential problems from cost and/or safety perspectives, particularly in a large-scale procedure. Another object of the invention is to provide a method which also permits the production of monoacetal derivatives and asymmetrical dibenzylidene compounds. Additionally, it is an object of this invention to provide a method of producing alditol acetal derivative compounds which permits the utilization of any type of surfactant component thereby facilitating utilization of such a procedure on a widespread basis and permitting the user greater versatility and fewer limitations on reaction component selections.
Accordingly, this invention encompasses a method of producing an alditol acetal derivative compound comprising the reaction of at least one aromatic benzaldehyde and at least one alditol in the presence of water, at least one mineral acid, and at least one surfactant. Furthermore, this invention encompasses a method of producing an alditol acetal derivative compound comprising the reaction of at least one-half mole of at least one aromatic benzaldehyde and at least one mole of an alditol in the presence of water, at least one mineral acid, and at most 0.01 mole (in relation to the amount of benzaldehyde present) of a surfactant. The actual reaction mixtures for these methods are also encompassed within this invention as well.
It has now been found that the addition of small molar amounts of long-chain surfactant to the reaction mixture permits a more effective yield of acetal alditol derivatives result through mineral acid catalysis of benzaldehyde and alditol components. Furthermore, such an inventive procedure permits tailoring of solubilities, and potential reduction of mineral acid amounts and/or concentrations to permit a more environmental, safe reaction as well.
Any alditol acetal derivative compound may be produced by the inventive method, including, as preferred but not as the limited type of alditol acetal compound, DBS compounds. Specific DBS derivatives produced by this inventive method include, as merely examples: 1,3:2,4-dibenzylidene sorbitol; 1,3:2,4-bis(p-methylbenzylidene)sorbitol; 1,3:2,4-bis(p-chlorobenzylidene)sorbitol; 1,3:2,4-bis(2,4-dimethyldibenzylidene)sorbitol; 1,3:2,4-bis(p-ethylbenzylidene)sorbitol, abbreviated as EDBS; 1,3:2,4-bis(3,4-dimethyldibenzylidene)sorbitol, abbreviated as 3,4-DMDBS; 1,3:2,4-bis(3,4-diethylbenzylidene)sorbitol; 1,3;2,4-bis(3-ethyl4-methylbenzylidene)sorbitol; 1,3:2,4-bis(4-chloro-3-methylbenzylidene)sorbitol, 1,3:2,4-bis(3-chloro-4-methylbenzylidene)sorbitol, 1,3:2,4-bis(3-bromo-4-isopropylbenzylidene)sorbitol, 1,3:2,4-bis(3-bromo-4-methylbenzylidene)sorbitol, and 1,3:2,4-bis(3-bromo-4-ethylbenzylidene)sorbitol. Other compounds include monoacetal derivatives, such as, without limitation 2,4-mono(3,4-dimethylbenzylidene)sorbitol, 2,4-mono(4-fluoro-3-methylbenzylidene)sorbitol, and the like (e.g., instead of two moles of aromatic aldehyde, only one is reacted with the alditol) and tri-acetals (e.g., three moles of aromatic aldedhyde to one of alditol). Furthermore, asymmetrical compounds may be produced, such as, without limitation: 1,3-O-(3,4-dichlorobenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-difluorobenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dichlorobenzylidene):2,4-O-(3,4-dimethoxybenzylidene)sorbitol, 1,3-O-(3,4-dichlorobenzylidene):2,4-O-(5-indanylidene)sorbitol, 1,3-O-(4-nitrobenzylidene):2,4-O-(3,4dimethylbenzylidene)sorbitol, and 1,3-O-(4-nitrobenzylidene):2,4-O-(3,4-methylenedioxybenzylidene)sorbitol, 1,3-O-(4-fluoro-3-methylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbenzylidene):2,4-O-(4-fluoro-3-methylbenzylidene)sorbitol, 1,3-O-(4-fluoro-3-methylbenzylidene):2,4-O-(3-fluoro-4-methylbenzylidene)sorbitol, 1,3-O-(3-fluoro-4-methylbenzylidene):2,4-O-(4-fluoro-3-methylbenzylidene)sorbitol, 1,3-O-(4-fluoro-3-methylbenzylidene):2,4-O-(4-chlorobenzylidene)sorbitol, 1,3-O-(4-chlorobenzylidene):2,4-O-(4-fluoro-3-methylbenzylidene)sorbitol, 1,3-O-(4-chloro-3-methylbenzylidene):2,4-O-(3-chloro-4-methylbenzylidene)sorbitol, 1,3-O-(3-chloro-4-methylbenzylidene):2,4-O-(4-chloro-3-methylbenzylidene)sorbitol, 1,3-O-(4-fluoro-3-methylbenzylidene):2,4-O-(5xe2x80x2,6xe2x80x2,7xe2x80x2,8tetrahydro-2-napthylidene)sorbitol, 1,3-O-(5xe2x80x2,6xe2x80x2,7xe2x80x2,8xe2x80x2-tetrahydronapthylidene):2,4-O-fluoro-3-methylbenzylidene)sorbitol, 1,3-O-(4-Chloro-3-methylbenzylidene)-2,4-O-(5xe2x80x2,6xe2x80x2, 7xe2x80x2,8xe2x80x2-tetrahydro-2-napthylidene)sorbitol, 1,3-O-(5xe2x80x2,6xe2x80x2,7xe2x80x2,8xe2x80x2-tetrahydronapthylidene):2,4-O-(4-chloro-3-methylbenzylidene)sorbitol, 1,3-O-(3-bromo-4-ethylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3-bromo-4-isopropylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3-bromo-4-methylbenzylidene):2,4-O-(3,4-dimnethylbenzylidene)sorbitol, 1,3-O-(4-chlorobenzylidene):2,4-O-(3-bromo-4-isopropylbenzylidene)sorbitol, 1,3-O-(4-t-butylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbenzylidene):2,4-O-(t-butylbenzylidene)sorbitol, 1,3-O-(3,4-dimethoxybenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbenzylidene):2,4-O-(3,4-dimethoxybenzylidene)sorbitol, 1,3-O-(3,4-methylenedioxybenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbenzylidene):2,4-O-(3,4-methylenedioxybenzylidene)sorbitol, 1,3-O-(4-isopropylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbenzylidene):2,4-O-(4-isopropylbenzylidene)sorbitol, 1,3-O-(3,4-dimethylbeznylidene):2,4-O-(2-naphthylbenzylidene)sorbitol, and 1,3-O-(2-naphthylbenzylidene):2,4-O-(3,4-dimethylbenzylidene)sorbitol.
Such a diacetal compound, as well as any type of DBS system, may be produced through the condensation reaction between two moles of an aromatic aldehyde and one mole of a polyhydric alcohol. The aldehyde and polyhydric alcohol are generally provided in the reaction mixture in a ratio from 1:1 to 4:1, preferably 1.5:1 to 2.5:1, respectively. The aromatic aldehydes are single or fused double ring aldehydes having at least one unsaturated hydrocarbon ring, and include benzaldehyde, naphthaldehyde, 5-formylindan and 6-formyltetralin. The aromatic aldehydes may be unsubstituted or have from one to five substituent groups selected from C1-6 alkyl, C1-6 alkoxy, hydroxy, halogen, C1-6 alkylthio, C1-6 alkylsulfoxy, C3-5 alkylene forming a carbocyclic ring with adjacent carbon atoms on an unsaturated hydrocarbon ring, carboxyl, (C1-C20 alkyloxy)carbonyl, (C1-C20 alkyloxy)ethyloxycarbonyl, (C1-C12 alkyl)phenyl, halogenated phenyl, (C1-C12 alkoxy)phenyl, (C1-C12 alkyloxy)ethyloxyethyloxycarbonyl and (C1-C12 alkyloxy)ethyloxy-ethyloxyethyloxycarbonyl groups, methylenedioxy (e.g., piperonal), or any of the benzylidene groups may be polyphenyl (such as naphthyl). Preferably, the aromatic aldehyde is selected from unsubstituted benzaldehyde, benzaldehyde having from one to three substituent groups selected from C1-4 alkyl, halogen and C3-5 alkylene forming a carbocyclic ring with adjacent carbon atoms on an unsaturated hydrocarbon ring, including p-methyl, p-ethyl, 2,4-dimethyl, 3,4-dimethyl and 2,4,5-trimethyl benzaldehyde, 5-indan aldehyde and 5xe2x80x2, 6xe2x80x2, 7xe2x80x2, 8xe2x80x2-etrahydro-2-naphthaldehyde, or any of the corresponding benzaldehydes to the asymmetric or monoacetal compounds listed above. Of course, in order to produce mostly monoacetal compounds, a molar ratio of alditol to benzaldehyde of about 1:1 is necessary while triacetals require about a 1:3 molar ratio in general.
Mixtures of the aromatic aldehydes may be provided and will result in a distribution of diacetals having the same or different aromatic components, referred to as symmetric and asymmetric diacetals, respectively. The aromatic aldehydes typically react with the polyhydric alcohol to form acetals in the 1:3 and 2:4 positions. Also within the scope of the present invention are triacetals formed by the condensation of three moles of an aromatic aldehyde and one mole of a polyhydric alcohol having six or more hydroxyl groups. The triacetals are typically formed at the 1:3, 2:4 and 5:6 positions of the alcohol.
The polyhydric alcohols have five or more hydroxyl groups. The sugar alcohols represented by the formula HOCH2(CHOH)n CH2OH, where n=3-5, have been found to be especially useful. Preferably, the polyhydric alcohol is a pentahydric or hexahydric alcohol, most preferably xylitol or sorbitol. The polyhydric alcohol can be added to the reaction mixture as a solid, molten liquid, or as an aqueous solution.
The reaction medium for this inventive procedure is water, although small amounts of other solvents (such as alcohols, benzene, and the like) may be present as minor impurities. The water may also comprise other consituents such as salts (e.g., chlorides, sulfates, and the like), although it is preferred that the water be deionized prior to utilization within the method. The aqueous nature of this inventive process thus provides a cost-effective process (with such a plentiful, inexpensive, reusable, raw material) which is safe to handle and use, for clear reasons.
The mineral acid is selected from primarily hydroacids, such as, without limitation, hydrochloric acid, sulfuric acid, phosphoric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, sulfurous acid, carbonic acid, phosphorous acid, and the like. Such a component is used as the actual catalyst to effectuate the acetalization of the alditol backbone. Although concentrated varieties of such acids are possible, it has also been found that not only is a safer reaction permitted through utilization of less concentrated compositions (for instance, and without limitation, instead of 12M HCl, concentrations of from 5 to 7, more preferably about 6 to 6.5M HCl), but a more effective reaction in terms of yield of acetal alditol product is potentially available as well. This phenomenon is more prevalent which symmetrical DBS compounds are formed, although asymmetrical DBS compounds may also benefit from such a concentration reduction.
As noted above, the catalysis of reactants within the inventive reaction mixture is highly dependent upon the ability of the catalyst to actually contact and thus effectuate catalysis between the components of the mixture itself. Solubility of components within the aqueous acid system is thus of utmost importance; more thorough mixing (and thus greater contact) between catalyst and components permits more effective and higher yields of acetal alditol product. The surfactant component of this inventive reaction is thus of utmost importance as well to effectuating the desired high yield, high purity results. The types of surfactants proper for such a reaction are virtually endless and may be tailored for certain situations, including, without limitation, the solubility of the benzaldehydes within the aqueous acid reaction mixture, environmental considerations, handling issues, cost, availability, compatibility with other components, and the like. Thus, the list of possible surfactants are those which are anionic, cationic, amphoteric, zwitterionic, and nonionic in nature. Compositions of more than one such surfactant may be utilized within the inventive process as well. For this invention, the broad term surfactant is intended to include any long carbon chain (e.g., 6 carbons or greater)-containing compounds with pendant groups such as, without limitation, hydroxyls, alkoxyls, carboxylates and acids, sulfonic acids and sulfonates, quaternary ammoniums, phosphoniums, phosphonic acids and phosphonates, and the like. As anionics, more specific types may be sulfonates, including long-chain substituted-arylsulfonic acids, and the like; cationics include quaternary ammonium salts, phosphonium salts, protonated long chain amines, and the like; nonionics include long-chain substituted phenols, alkoxylated alkanes and alkenes, long-chain alkylarnines, including octadecyl phenol, and the like. The amount of such surfactants added within the inventive reaction and inventive reaction mixture is in relation to the amount added of the benzaldehyde.
The molar ratio between benzaldehyde added and surfactant(s) is from about 1:0.1 to about 1:0.000001; preferably from about 1:0.05 to about 1:0.0001; more preferably from about 1:0.02 to about 1:0.0005; and most preferably between about 1:0.01 and 1:0.0005. In such a situation, the amount added of benzaldehyde is dictated by the type of acetal alditol product desired (mono-, di-, or tri-acetal) in relation to the molar amounts needed of the alditol component. The amount of aqueous acid to be added should be from about 1 to 5 times the amount of the total weight of benzaldehyde and alditol present, with concentrations anywhere between about 2M and 18M depending upon the acid used.
The reaction takes place at room temperature, enerally, although some heating may be followed. Some acids also react exothermically with water (such as sulfuric acid) to generate some internal heat within the system itself All of the components may be mixed together initially, or the surfactant and acid may be first mixed together (under heat, if desired), with subsequent addition of the reactants. The time for reaction may take anywhere from a few minutes (e.g., 10 minutes, as one non-limiting example) to a few days (e.g., 48 hours, as one non-limiting example) depending upon the batch size and the amount of acid catalyst present. Generally, a reaction time of from about 8 hours to about 48 hours, more preferably from about 8 hours to about 36 hours, is sufficient to produce the desired high yield acetal alditol derivatives. Upon production, a solid precipitate is generally formed and neutralized to a pH of from about 6 to about 9.5, with a pH of from about 7.5 to 9, more particularly from about 8.5 to 9, to permit safer handling. Any neutralizer for mineral acids may be utilized such as strong bases like sodium hydroxide, potassium hydroxide, and the like, for this purpose. The washed product can then be dried and collected as a crystalline structure for further utilization in a variety of procedures.

Method of producing high yield alditol acetals with mineral acids and surfactants


When editing a digital image that has previously been saved in a lossy manner (whether such losses result from the editing operations and/or from inherently lossy image file formats such as JPEG), each additional editing session typically compounds the overall losses. As an alternative, we disclose creating and storing a proxy for an edited image, the proxy including a baseline image and a series of meta data representing editing operations performed on that image. During a subsequent editing session, the edited image can be partially or wholly reconstructed by applying the meta data to the baseline image, resulting in a comparatively lossless version thereof. The reconstructed image can be used as a starting point for additional edits, thereby minimizing the compound losses that would otherwise have resulted.

Digital images are often too large to conveniently handle and transmit from one party to another. For example, a moderate resolution image such as a 16-bit color image acquired using a 1024×768 pixel resolution occupies 4.5 MB. Over a 56 Kbits/sec modem connection, such an image would take 11 minutes to download. Therefore, images are commonly compressed in accordance with, and stored in the form specified by, standard compression protocols. Some protocols in common use, for example, those resulting in the GIF and some types of TIFF file formats, are lossless. In those formats, the compressed image does not lose any information compared to the original image. However, for many applications the degree of compression offered by lossless compression is not enough. In such cases, a higher degree of compression can be obtained by using lossy compression, which discards some information in the original picture in order to achieve greater compression. Thus, the most commonly used format (JPEG) is lossy. Other examples of lossy formats include JFIF and MPEG (for video).
We will illustrate the occurrence of lossiness using JPEG, which is perhaps the best known and most commonly used file compression standard. JPEG involves 5 basic steps: (1) parsing an image into macroblocks; (2) transforming the image into the frequency domain using a discrete cosine transform (DCT); (3) quantizing the DCT coefficients; (4) run-length encoding the quantized DCT coefficients; and (5) variable-length encoding the result.
In step (1), the image (a matrix of pixel values) is decomposed into 8×8 blocks known as macroblocks.
In step (2), each macroblock is operated on by a DCT module to yield an equivalent 8×8 block of frequency domain coefficients. DCT is simply the counterpart, in the digital domain, to the fourier transform in the analog domain.
In step (3), the coefficients of each macroblock are quantized in a process that typically involves division by an integer and rounding off. For example, if the divisor is 10, values 1049, 1000 and 951 would divide to 104.9, 100.0 and 95.1, which might (depending on the desired degree of rounding) all round to 100. It is this quantizing step that leads to the lossy nature of JPEG.
In step (4), the quantized values are further (but losslessly) compressed using run-length encoding (RLE). RLE is a technique for reducing redundancy in a string of information. For example, in a conceptual illustration, a string such as 77777777222222 might be represented as the shorter string 7(8)2(6), where each parenthetical value in parenthesis represents the number of repetitions of the preceding value.
In step (5), the RLE string is further (losslessly) compressed by a process called variable-length encoding (VLE). In VLE, the relative frequencies of occurrence of each element in the string to be encoded are determined, and more frequently occurring strings are encoded using shorter codes. For example, in a conceptual illustration, in a string where 7(8) occurred most frequently and 2(6) occured the least frequently, 7(8) might be represented using a single digit code, while 2(6) might be represented using multiple digits.
Finally, the VLE string is written to storage.
The foregoing assumes that the image consists of one value per pixel. This may be true for monochromatic or grayscale images but, in general, images will be comprised of three color values per pixel location. For example, the image might be in a red-green-blue (R,G,B) color space, or in a luminance +2 chrominance (Y,Cb,Cr) color space. For color images steps (1)–(5) are typically performed on each color component separately. As a matter of convenience, we will refer to images without differentiating whether such images are grayscale or color, with the associated processing being understood to apply to each color component thereof in the case of color images.
In order to use a compressed image, the encoded image is first retrieved, then decoded using the mathematical inverse of the encoding protocol. For example, in JPEG, the DCT coefficients are recovered, then converted back to the spatial domain using an inverse discrete cosine transform (IDCT). Once converted back to the spatial domain, the image can be displayed and/or manipulated using well-known and widely commercially available image editing software such as Adobe Photoshop, as well as many others.
As illustrated above, each time an image is encoded and stored using a lossy compression protocol, some information is irreversibly lost. Thus, when a lossy encoded image is decoded, the image becomes visually degraded to some degree. Depending on the degree of loss, this degradation may or may not be apparent to the viewer.
However, the effect of several such individual degradations can become cumulative, depending on how the image is used. For example, suppose that a user acquires an image using a digital camera which encodes it using JPEG on a memory card. At this stage, the degradation might only be minimal. Later, the user downloads the image from the memory card onto his computer, and loads (decodes) it for viewing. At that point, the user decides to edit the image (for example, by cropping), then prints it and stores (reencodes) it onto his hard disk. The reencoding process introduces a further degradation relative to the original image seen at the digital camera's sensor. Upon printing, the user sees that one of the people in the picture suffers from red-eye (or green-eye in case of animals), so he loads (decodes) the image, uses his software to fix the problem, and stores (reencodes) it. The reencoding will again introduce further degradation.
As shown by this simple example, even a relatively common sequence of simple edits can result in substantial degradation if the image is reencoded between successive edits.
To use a crude analogy, the original image can be viewed as a sheet of paper, which is compressed (encoded) by crumpling the sheet into a ball. Each time the paper is smoothed out (decoded—say for editing) and then recrumpled (reencoded), the degradation becomes worse.
Of course, users can take steps to reduce such cumulative degradation. For example, it is often recommended to avoid saving (encoding) an image until all edits are finished, or to save intermediate versions using lossless formats such as TIFF or GIF. However, these techniques are often inconvenient, for example, when all editing cannot be performed in a single session, or cannot be anticipated. Also, sometimes images are to be edited by multiple persons at different times and different locations, where bandwidth constraints on transmission discourage the use of lossless file formats for intermediate versions.

Embedding editing commands in digital images


A plunger is formed of a soft magnetic material to have one end connected a regulation pin. A permanent magnet is affixed to a stationary portion, which is stationary relative to the plunger, to attract the plunger in a retreated direction. A coil generates a magnetic flux in an opposite direction of the permanent magnet to reduce a magneto attraction force, which attracts the plunger. A spring biases the regulation pin in an advanced direction. The spring applies a biasing force to the regulation pin to move the regulation pin in the advanced direction when electricity is supplied to the coil to reduce the magneto attraction force of the permanent magnet. A magnetism detection unit is located on a magnetic circuit, which conducts a magnetic flux generated by the permanent magnet and the coil, to detect a magnetic flux density.

Conventionally, a known valve lift control device is configured to control a lift of an intake valve or a lift of an exhaust valve of an internal combustion engine. A valve lift control device may rotate with a camshaft and may switch a position of a slider, which is movable in an axial direction relative to the camshaft. A known solenoid actuator may be employed to switch the position of the slider. For example, the solenoid actuator may alternately activate one of two regulation pins according to the movable direction of the slider. In this way, the solenoid actuator may fit a tip end of the regulation pin to a fitting groove formed in the slider.


A soft actuator for a suction-cup end effector bends or deforms in response to air pressure within bladders in the actuator. The walls of the air bladders, upon pressurization, expand to contact adjacent structure, such as other expanding air bladders, to move a constraining layer of the actuator from a rest position toward an actuated position. A gripper for engaging items is formed by the soft actuator and a suction cup.

The present disclosure relates to robotics, and more particularly actuators for end effectors.
In general, end effectors used in automated processes are categorized into impactive, which often use jaws or claws that contact and grasp an object; ingressive, which includes pins or the like to penetrate the surface of an object; astrictive, which work by vacuum or magneto-adhesion or the like; and contigutive, which work by an adhesion process, such as gluing or surface tension.
In commercial warehouses, such as fulfillment centers and like facilities, automated processes often employ impactive and astrictive end effectors to handle a vast variation in the shape, size, and mass of objects, as well as to handle randomly oriented objects. An example of a modern air-actuated end of arm tool is an air-actuated finger assembly in which each curved finger has upstanding air chambers. When the air chambers are pressurized, the curvature of the finger decreases, which causes the fingers to move relatively inwardly to grasp an object


A selectively controllable electromagnetic shield having an electromagnetic shielding material and a mechanism for selectively generating an aperture in the shield. The mechanism for selectively generating an aperture may be a magnetic field source that generates a magnetic field of sufficient strength to substantially saturate all or a portion of the shielding material. For example, a permanent magnet or DC electromagnet may be used to selectively saturate the shield. In its un-saturated state, the magnetic shield has a high permeability and functions as a flux path for the magnetic field. Once saturated, the permeability of the shield is substantially reduced so that the magnetic field lines are no longer drawn into the shield to the same degree. As a result, once saturated, a substantially greater amount of the electromagnetic field may flow through or around the shield in the saturated region.

In recent years, there has been a widespread increase in efforts to implement wireless power transfer systems in both commercial and residential settings. Wireless power systems offer the promise of eliminating power/charging cords for a wide range of electrically powered devices, including not only handheld electronics, such as cell phones, media players, wireless headsets and personal digital assistants, but also higher power devices, such as appliances, tools and electric vehicles. Efficient inductive power transfer has become an area of increasing scientific interest as it can solve some problems associated with traditional wired or contact power transmission. These include but are not limited to corrosion, mechanical friction, clutter and impracticality in places like underwater and subterranean applications. This wireless energy transfer is improved by the optimization of electromagnetic induction, circuit frequency resonance all achieved with advanced power electronics. One of the components of this technology is the precise delivery of the incident electromagnetic fields to the precise location where they are converted to power without broadcasting these fields inefficiently into the surrounding areas. Inductive wireless power transfer systems use electromagnetic fields to transfer power from the power supply to the remote device without the need for wires or any direct electrical contact. Given the nature of electromagnetic fields, many conventional wireless power systems provide improved performance with relatively close alignment between the wireless power supply and the remote device. This has lead to the development of wireless power transfer systems in which the remote device is placed in a specific location or within a relatively small distance from a specific location. For example, it is known to use parallel planar spiral coils in the wireless power supply (e.g. primary) and in the remote device (e.g. secondary) that are concentrically aligned in face-to-face relationship during power transfer. In these types of systems, the primary and secondary are typically of similar size. In some known solutions, the wireless power supply is in a housing, or dock, with a signature surface that forces the portable device to be placed in a specific target location and in a specific orientation. Although providing efficient power transfer, these types of systems lack the desired amount positional freedom that might be desired in some applications.
Although eliminating power/charging cords is by itself a significant and meaningful advantage, wireless power transfer may be even more appealing if the need for close alignment between the wireless power supply and the remote device was reduced or eliminated. From a user perspective, it can be desirable to be able to place a portable device in a random position and a random orientation within the boundaries of a charging surface. It may be even more desirable to the user if the target zone is substantially larger than the secondary device, thus allowing freedom from specific placement and orientation. With this in mind, a number of wireless power transfer systems have been developed to provide increased spatial freedom in aligning the remote device with the wireless power transfer supply. For example, it is known to use a large primary coil to transmit power to one or more smaller secondary coils which are located within the diameter of the large primary coil. Although providing increased spatial freedom, the large primary coil can increase stray electromagnetic fields and dramatically increase parasitic losses. With a large coil within a charging surface, the coil might emit stray electromagnetic field over the entire charging surface. Stray electromagnetic fields can interact with metal within remote device(s) placed on the charging surface, as well as other metal objects that might be placed within sufficient proximity to the wireless power supply. For example, stray electromagnetic fields may cause metal within the remote device to heat, thereby heating the remote device. As another example, stray electromagnetic fields can heat keys, coins, or other metal object placed in proximity to the wireless power supply. To provide some limit on the impact of stray electromagnetic fields, the power supply and/or remote device may have additional magnetic flux guiding materials that are capable of directing the shape of the electromagnetic field. These materials can be arranged to help limit the field from impacting metals within and without the remote devices. As an example, a flux guiding material may be placed between a coil and a battery, or printed circuit board, to reduce/eliminate the impact of the magnetic field on the battery or printed circuit board.
Another conventional option for providing increased spatial freedom is through the use of inductive coils that move behind, under, or above the charging surface to self-align with the portable device. In these solutions, the coils may move automatically by magnetic attraction, or by motorized mechanism, or by manual adjustment or mechanism. These types of system may include relatively complex mechanical and/or electro-mechanical systems that can significantly increase cost and create reliability issues. For example, mechanical assemblies involve moving parts tend to be more likely to fail than purely electronic systems. Systems based on magnetic attraction may have a limited range of movement that will vary with the strength of the attractor magnet and the amount of force required to move the primary. In addition to cost and reliability issues, motorized systems require time for the primary to be moved into the appropriate position. Manually adjusted systems require human intervention and therefore may not be as convenient as they would be if the remote device could be placed randomly within a large zone and forgotten.
In other conventional systems, positional freedom is achieved through the use of arrays of coils behind, under, or above a charging surface. These arrays may include fixed, discrete charging locations, such as a charging pad with two or more primary coils arranged to allow multiple devices to charge side by side. In other embodiments of an array, there may be multiple layers of coils that overlap in a way that allows for less discrete positioning of the secondary device on the charger. Array-type systems require multiple coils and therefore can be more expensive to implement. They may also involve relatively complex controls, such as additional electronic hardware, for determining which coil(s) in the array to energize and for selectively switching the coils to the proper configuration to provide power to the remote device.
The need to meet the ever increasing consumers demand for convenient portable devices is a strong driving force to exploring the potentials of closely coupled inductive power transfer. The basic concepts of this technology have been described in detail in various publications. However, it is believed that inadequate discussion has been directed toward the issue of precise delivery of the magnetic flux for inductive power transfer, as is the case in most transmission pads. Some of the issues can be described as those of spatial freedom (that is, being able to receive power at different locations on a power transfer surface or transmitting pad), and of electromagnetic field broadcast (that is, ensuring magnetic flux is substantially limited to the flux receiving system and does not significantly transfer into the environment). These are areas of some importance to the technology, given the challenges of interference, parasitic heating and regulatory emission limits.
This problem of electromagnetic field broadcast has traditionally been addressed using power electronics to shut down transmission during non-active periods, but even this technique has residual power being broadcast due to the presence of the communication circuits. Furthermore, such a technique including single-coil transmission systems is generally only applicable to small surface area transmission pads, which do not power multiple devices at the same time. In the case of wide surface area charging systems (delivery of power to multiple remote devices), the field broadcast challenges have gone largely undiscussed in literature that addresses multiple receiver transmission. This is because shutting down the circuit at a particular location due to the removal of one remote device will deprive another remote device of power. Conversely, if the electronic algorithm doesn't include shutdown of the system at one location when one or multiple devices are being charged, then a case of magnetic field broadcast into the surroundings can occur, with its adverse effects.

Selectively controllable electromagnetic shielding