In a WDM transmission system employing a plurality of short wavelength bands having great attenuation due to optical fiber transmission, an optical repeater is constructed of a first multiplexing section and a second multiplexing section. The first multiplexing section is used for wavelength-multiplexing both the excitation light from a first Raman excitation light source, which distributively amplifies an S+ band included in light propagating through an optical fiber, and the light propagating through the optical fiber. The second multiplexing section is used for wavelength-multiplexing both the excitation light from a second Raman excitation light source, which distributively amplifies an S+ band included in light propagating through an optical fiber, and the light propagating through the optical fiber. The first and second multiplexing sections are provided between the optical fibers disposed between end offices. Thus an equal and satisfactory optical SN ratio even at any band are obtained.

(1) Field of the Invention
The present invention relates to an optical transmission system, an optical repeater, and an optical transmission method suitable, for example, for a wavelength division multiplexing (WDM) system employing a short wavelength band.
(2) Description of the Related Art
A WDM system (optical transmission system), which employs a wavelength-multiplexed signal light consisting of a signal light having a plurality of different wavelengths, is being employed to transmit an electrical signal such as voice, data, etc.
In this WDM system, one end office (or one transmission end office) optically modulates and multiplexes electrical signals output from an exchange and transmits the wavelength-multiplexed signal light to an optical repeater of the initial stage. The signal light from the optical repeater is transmitted to a plurality of optical repeaters and is demodulated by the other end office. The demodulated electrical signals are transmitted to other exchanges.
As a conventional method of compensating for an optical signal-to-noise ratio (hereinafter referred to as an optical SN ratio), there is a method of previously emphasizing the optical repeater output of a short wavelength band component by pre-emphasis, or a method of exciting and amplifying this short wavelength band component. The pre-emphasis is the method of equalizing the received optical SN ratios of signal wavelengths by previously reducing at a transmitting side the optical SN ratios of signal wavelengths having less SN ratio degradation.
FIGS. 17A to 17C are diagrams used to explain pre-emphasis, the horizontal axis representing optical wavelengths and the vertical axis representing optical SN ratios. The curve shown in FIG. 17A represents the reception characteristic of a receiving station and shows that the reception characteristic has been degraded at the short wavelength band. The curve shown in FIG. 17B represents a transmission characteristic employing pre-emphasis and shows that a signal light is transmitted after a compensation for transmission degradation is made at a transmitting side. As a result, a flat characteristic is obtained at a receiving side, as indicated by a reception characteristic in FIG. 17C.
If the light power (hereinafter referred to as power) of transmission light to be output from an end office or optical repeater is made too great by the pre-emphasis, a signal light with a plurality of wavelengths will increase the influence of a nonlinear optical effect and develop the nonlinear distortions of cross phase modulation and self-phase modulation, resulting in transmission quality degradation. Because of this, pre-emphasis is often employed in optical auxiliary repeaters.
A general optical repeater is constructed by combination of a centralization amplifier and a distributive amplification. There are two types of centralization amplifiers. One type is an optical fiber, doped with a rare-earth element, such as an erbium-doped fiber (EDF), and light within the optical fiber is excited to optically amplify a transmission signal intensively within the optical fiber. The other type is a dispersion compensation fiber with high nonlinearity in which a transmission signal is intensively amplified by excitation. The centralization amplifier, which employs a fiber doped with a rare-earth element, is used to amplify transmission light by combination of a specific amplification band that a rare-earth element has and excitation light.
The distributive amplification is the method of employing an excitation light source of specific wavelength and the physical properties of an optical fiber employed as a transmission path, and amplifying a signal light distributively by employing optical repeaters between end offices and between optical repeaters and the entire transmission line between the end offices. The distributive amplification normally employs Raman amplification.
The Raman amplification is the technique of performing optical amplification by employing the Raman scattering effect of an optical fiber itself. In general, a Raman amplifier is used for transmitting light, which has a wavelength about 100 nm shorter than that of a signal light, onto a transmission line to amplify the signal light propagating through the transmission line.
In addition, various techniques related to optical repeaters have been proposed (e.g., Japanese Laid-Open Patent Publication No. 2000-330145 (hereinafter referred to as known reference 1), Japanese Laid-Open Patent Publication No. HEI 3-239028 (hereinafter referred to as known reference 2), etc.)
In the case where WDM transmission is performed with a plurality of wavelength bands, the light energy on the short wavelength side excites the light on the long wavelength side by Stimulated Raman Scattering (SRS). As a result, the intensity of received light on the short wavelength side is reduced and the intensity of received light on the long wavelength side is increased.
In addition, in the case of expanding a wavelength band for WDM transmission by an attenuation characteristic that a normal single-mode fiber has, the light loss is minimized at the C band and L band. On the other hand, in the bands on the short wavelength side and long wavelength side with the C and L bands as the center, the light loss is increased. For the light on a short wavelength side such as a S+ band shown in FIG. 3 to be described later, the light loss is further increased.
Therefore, there is a need to improve the intensity of the light on the short wavelength side where loss due to Stimulated Raman Scattering and loss due to optical fibers are added together.
Because of this, in the case where an end office performs pre-emphasis, an output for a short wavelength band is set high, or the characteristic of a centralization amplifier within an optical repeater is determined so that an output for a short wavelength band becomes high, or the intensity of excitation light for distributive amplification with respect to a short wavelength band is increased.
However, if the output of the signal light is made greater, the influence of a nonlinear optical effect will increase in a transmission line, and because of the influence of Stimulated Brillouin Scattering (SBS), an end office, etc., can input only a fixed quantity of power to an optical fiber. This means that a signal light with a predetermined power cannot be transmitted over an optical fiber.
In the case where power input to an optical fiber is great even if the signal light power at a sender is less than a threshold value for Stimulated Brillouin Scattering, there is a possibility that between a plurality of signal lights, noise will occur due to four light wave mixing or inter phase modulation, etc., and will degrade transmission quality.
In the case of performing distributive amplification by excitation light emitted from an optical repeater, light with a wavelength shorter than the short wavelength of a signal light (e.g., light with a wavelength about 100 nm shorter than that of a signal light to be amplified) has to be employed as excitation light. This is because light on a short wavelength side is greatly attenuated by an optical fiber. Because of this, light on a shorter wavelength side than a short wavelength band employed as a signal light is greatly attenuated by an optical fiber, and the intensity of excitation light required for compensating for the attenuation of a signal light in a short wavelength band becomes extremely great.
On the other hand, if the intensity of excitation light is increased, the problem of Stimulated Brillouin Scattering will also occur, as in the case where an end office performs pre-emphasis and the case of a centralization amplifier. Because of this, there is a possibility that the required power cannot be input to an optical fiber.
In the case where the light intensity is made the same as the intensity of light in other wavelength bands by a centralization amplifier and pre-emphasis performed by an end office, the power is also greatly attenuated once within an optical fiber. Because of this, the optical SN ratio is degraded. Thereafter, even if the signal light is amplified, the noise component will become great and it will become difficult to reproduce the signal light.

Optical transmission system, optical repeater, and optical transmission method


A process of preparing a polyalkylene terephthalate comprising reacting an alkylene diol and an aromatic dicarboxy compound that is an aromatic dicarboxylic acid, aromatic dicarboxylic (C1-C3)alkyl ester, or a combination thereof, wherein ester interchange and polymerization occurs in the presence of a catalyst complex formed by the reaction of tetraisopropyl titanate and a boron, phosphorous or nitrogen-containing complexing agent, which catalyst can be synthesized in situ prior to ester interchange and introduced to a mixture of the alkylene diol and the aromatic dicarboxy compound prior to ester interchange.

This invention relates to methods for the manufacture of polyalkylene terephthalate resin compositions. In particular, a polyalkylene terephthalate resin such as poly(butylene terephthalate) is prepared employing a titanium-containing catalyst complex comprising a phosphorous, nitrogen, or boron atom.
Polybutylene terephthalate (PBT) resin is a well-known polyalkylene terephthalate that is semi-crystalline and has several desirable properties alone or in blends. Compared to amorphous resins such as acrylonitrile butadiene styrene (ABS), polycarbonate, and polystyrene, a semi-crystalline resin like PBT can show higher solvent resistance, strength, and stiffness due to the presence of crystalline spherulites in the resin. PBT resin is used in many applications in which its solvent resistance, strength, rigidity, and lubricity are needed, most commonly in durable goods that are formed by injection molding. Applications include electronic and communications equipment, computers, televisions, kitchen and household appliances, industrial equipment, lighting systems, gardening and agricultural equipment, pumps, medical devices, food handling systems, handles, power and hand tools, bobbins and spindles, and automotive parts in both under-the-hood and exterior applications. Additionally, PBT is widely used to form electrical connectors. Through its many blended products PBT can be tailored to a wide variety of applications.
It is generally known that PBT can be made by reacting 1,4-butanediol (BDO) with terephthalic acid (TPA) or dimethyl terephthalate (DMT) in the presence of a transesterification catalyst. U.S. Pat. Nos. 7,129,301; 6,020,393; 4,328,059, and US Patent Pub. 2005/0113534 A1 disclose various catalysts for the polymerization of polyesters.
Commonly used catalysts for the polymerization of PBT include tetraalkyl titanates. Among the various titanates are tetraisopropyl titanate, tetrabutyl titanate, and tetra(2-ethylhexyl) titanate. For example, JP 60147430 discloses a method of producing polyester by esterifying terephthalic acid, adipic acid and 1,4-butanediol in the presence of a titanium compound and a pentavalent phosphorus compound. U.S. Pat. No. 6,303,738 discloses a process for producing copolyester containing adipic acid in the presence of TYZOR® IAM (available from DuPont), which is prepared through the combination of tetraisopropyl titanate (TPT) and a mixture of butyl phosphate and dibutyl phosphate.
The catalyst used to prepare PBT is not typically quenched (deactivated) at the end of the polymerization process. An active catalyst in the resin, however, can sometimes lead to undesirable reaction of the PBT in subsequent processing. Blends containing polyalkylene terephthalates such as PBT, on exposure to high temperature and humidity, can exhibit hydrolytic degradation, especially under caustic conditions. Another problem associated with some blends is transesterification, which can lead to loss of mechanical properties. Catalyst quenchers can be added to thermoplastic compositions that comprise the polyalkylene terephthalate resin to prevent such transesterification, but such quenchers can also promote degradation of polymer chains and contribute to decrease in hydrolytic stability. Quenchers have included conventional phosphorous derivatives such as phosphoric acid and phosphates. Phosphite stabilizers are less satisfactory because of the tendency to be unstable to both hydrolysis and oxidation.
Insufficient hydrostability of polyalkylene terephthalate can lead to chain cleavage, the extent of which can depend on the exact conditions of exposure to water or humidity. Temperature, time of exposure, and pH are all important. Both acids and bases can catalyze ester hydrolysis of polyalkylene terephthalate. Thus, if exposed to water that is acidic or basic, or if the polymer matrix involves free acidic or basic additives, decomposition can be accelerated. Since one of the reaction products of PBT hydrolysis is itself a carboxylic acid, the hydrolytic decomposition of PBT is autocatalytic.
In view of the above, there remains a need for new catalysts for the production of polyalkylene terephthalates that are effective in polymerization but that do not have potentially adverse effects in association with the polyalkylene terephthalate resin, or in blends thereof, after polymerization has been completed.

This patent is subject to a terminal disclaimer.

Method for the preparation of polyalkylene terephthalate resin compositions employing titanium-containing catalyst complex


A method and apparatus for mixing chemical additives into contaminated liquids and electrolyzing contaminated liquids includes the positioning of a vibratable element, such as a metal spring, within a cylindrical liquid conduit. A treatment additive is introduced into the liquid upstream of the vibratable element and the liquid is directed through the conduit. The flow of the liquid in proximity to the vibratable element causes the element to vibrate and mix the liquid and the additive. The conduit and the vibratable element may be electrically charged such that the flow of the liquid in proximity to the charged and vibrating element causes an electrical charge to be imparted to the liquid. The vibration of the element also prevents fouling.

The present invention generally relates to the treatment of contaminated liquid, such as wastewater. More particularly, the present invention defines an innovative apparatus and method for the mixing and electrolytic treatment of contaminated liquid which may contain electrolytes, dissolved solids, suspended solids, dissolved proteins, dissolved gasses, biological microorganisms and the like, which would advantageously be treated utilizing electrocoagulation, electrofloculation or electroflotation.
It is often desirable when treating contaminated fluid, such as wastewater, to add chemical additives to remove such contamination. For example, cationic or anionic chemicals may be added in predetermined amounts and which are intended to chemically bind with certain contaminants in order to facilitate their removal from the liquid. Such chemical additives, in the form of liquids, gases, or even solids, can be added to the contaminated liquid to be treated in order to alter pH, solution ionic strength, etc., which can be used beneficially to remove the contaminants.
In the past, such mixing methods and systems have comprised adding such chemical additives to a holding tank containing the contaminated liquid and mixing the chemical additives and liquid with an electric mixer having blades or the like. Other methods have included the injection of such chemical additives to a liquid stream as it enters into a hydrocyclone, or at a later stage before the previously treated contaminated liquid is introduced into a separation or holding tank. Most such methods and systems require rather complicated sub-systems or devices to adequately mix the contaminated liquid and intended chemical additives. Some of these devices and systems require power. Others require a relatively large footprint or space. The cost, complexity, and inconvenience of such systems and devices have sometimes provided disadvantages. Accordingly there is a need for a method for mixing chemical additives into contaminated liquids which does not require power, can be retrofitted into existing systems, and is of a relatively simple and inexpensive design.
It is well known by those skilled in the art, that the passage of electrical current through an electrically conductive liquid solution provides a useful means of affecting physical and chemical behavior in the treated liquid solution. Electrolysis is a general term describing a process in which chemical and physical reactions are stimulated by the passage of electrical current through a solution of an electrolyte. Of interest in the present invention is the electrolysis of aqueous electrolyte solutions.
An electrolytic apparatus as it applies to the scope of the present invention, is defined as a physical environment in which conductive electrodes are immersed in a solution containing an electrolyte. These electrodes are connected to an electrical power supply, such that a difference of electrical potential is present between the electrodes. The solution containing an electrolyte is in intimate physical contact with the electrodes, allowing a flow of electrons between the electrodes, and through the liquid solution. The relative amount of current flow through the solution is determined by the conductivity of the solution, relative to the electrode cross-sectional area.
The number of ions present in this solution determines the conductivity of an aqueous solution. The pH of the solution is the concentration of hydrogen ions present in the solution. The pH value defines the relative acidity or alkalinity of a solution. The pH also determines the "iso-electric point" in the solution, that is, the charge potential and sign of non-ionic suspended colloidal particles in the electrolyte solution. Solutions of electrolytes may contain acids, bases, or salts, made up of electrically charged particles, or "ions". There is an equilibrium of positive and negative charges in such solutions called "cations" (+ charge) and "anions" (− charge). The splitting of compounds into cations and anions is referred to as ionization. Ionized solutions allow the transfer of electrons through the solution, when a sufficient difference of electrical potential is presented across such a solution. Thus, this mechanism allows the use of electrolytic cells comprising liquid in contact with solid conductive electrodes. A variety of electrochemical effects are stimulated by such an electron flow.
There are several methods of electrolysis which are well-known, including direct electrolysis, indirect electrolysis, electroflotation, electrocoagulation, and electroflouculation. Each will be briefly described below.
Direct Electrolysis is the electrochemical oxidation or reduction of pollutants occurring at the electrode surfaces without the involvement of other substances in the solution. Such treatment has been used for the destruction of organic pollutants such as phenols, aromatic amines, pesticides and the like, while inorganic compounds such as cynides have been desirably broken into non-toxic components. A major problem with apparatus for direct electrolysis is that the useful reaction zones are limited to the electrode interfacial areas, said areas including liquid layers no more than tens of molecules thick. Thus, a small fraction of the total liquid volume is subjected to direct electrochemical influence. The flowing liquid in such systems is isolated from treatment by boundary layer effects and diffusion time. The prior art tries to overcome these limitations by increasing electrode area in various ways, such as packed beds of conductive electrode particles, screens, surface treatments to increase surface area, and the like. Additionally, liquid flow rates are often restricted to improve the probability of the translation of microscopic volumes of the contaminated liquid into close proximity with electrode interfacial areas by thermodynamic means. Such flow rate restriction can lead to fouling, and low probability of useful treatment.
Indirect Electrolysis of pollutants relies on the electrochemical generation of reactive intermediate compounds, which then react with the targeted pollutant component. Powerful reactive agents such as hydroxyl radicals, hydrogen peroxide, ozone, hypochlorite or chlorine may be electrolytically generated. These reactive species then mix with the bulk liquid where secondary reactions occur. While these reagents, once produced, are useful in the treatment of wastewater, the overall efficiency of the treatment is still subject to the limitations of fouling, low flow rate, and poor mixing discussed in the previous paragraph.
Electroflotation utilizes dissociated oxygen and hydrogen gas volumes produced by the electrolytic process. Desirably small volumes of dissociated gas are often utilized to capture suspended hyrophobic contaminants into agglomerations of gas bubbles and contaminant particles, which then allow gravity separation of the contaminants. Secondary, non-ionic mechanisms, sometimes referred to as "field effects" can desirably effect suspended solids in waste streams. Thus, in addition to hydrophobic bubble attachment, there are colloidal effects that result from pH gradients in the liquid between electrodes, causing de-stabilization and agglomeration of colloidal suspensions.
Electrocoagulation is the destabilization of colloidal suspensions utilizing electrolytic effects. Secondary reactions resulting from electrolysis produce dissolved species, which can change pH and thus the iso-electric point of colloidal particles, breaking the suspension of colloids, and allowing their removal through subsequent attachment to charge sites on polymer additions.
Electrofloculation is an electrolytic process wherein particles in the solution are caused to be bridged or coalesce into groups as a result of intermediates generated by electrolysis, allowing their removal from the liquid stream using flotation, sedimentation, or filtration. There are many desirable electrolytic treatment methods, which may in themselves, or in combination with other treatment effect useful results.
Unfortunately, electrolytic treatment has in the past been limited in utility due to fundamental performance limitations of the prior art apparatuses and methods. Some of the problems with prior art electrolytic apparatus for wastewater treatment are:
1. Electrode fouling due to contaminants adhering to electrode surfaces, caused by low flow rates, low turbulence, and excessive electrode area. Electrode fouling lowers effective electrode area, and lowers operating efficiency.
2. Electrode blinding, due to low velocity of liquid flow, which allows the coalescence of undesirably large gas bubbles near electrodes, thus decreasing the effective cross sectional area of conductive electrolyte and lowering electrical efficiency.
3. Liquid passage plugging. Due to low liquid velocity typically employed in prior art apparatus, the low liquid velocity in the boundary layer of the electrode solid/liquid interface allows a gradual buildup of contaminant material. As the contaminants build up, the liquid path can be reduced to the extent that the liquid channel becomes plugged.
4. Low electrical efficiency in that the low liquid velocity utilized in the prior art to preclude plugging requires large electrode spacing, electrical energy utilization increases with commensurate decrease in performance. Desirable electrochemical effects of the process occur in close proximity to the electrodes, while current flow through the bulk liquid layer primarily effects undesirable heating due to IR losses in the bulk electrolyte.
5. Low mechanical mixing energy. In the liquid path of the prior art electrochemical devices, the liquid flow is primarily laminar. Turbulence generating devices utilized in some prior art devices, in an effort to improve mixing, tend to generate undesirable localized shear in the liquid, disturbing forming floccules, and lowering contaminant removal efficiency. Due to poor mixing, a large fraction of stream constituents may not be subjected to the desirable electro-chemical effects near an electrode. In electroflotation, bubbles may not optimally attach to hydrophobic waste particles. In electrocoagulation/electrofloculation, high shear may disrupt agglomerations of separable contaminants.
6. Complex mechanical configuration. Because prior art devices utilize excessive path lengths to overcome the inefficient electrode behavior, there may be multiple electrodes, packed beds, baffles, spacers, multiple seals and the like required. In addition, power distribution and bussing to individual electrodes is required. These arrangements are expensive to fabricate, assemble, and test.
7. High maintenance requirements. The complex nature of the prior art, as described above, require a higher level of maintenance, and increased downtime, increasing operating costs.
8. Large footprint requirements. The prior art being more complex and less efficient, requires more physical space for a given process throughput. This translates to a higher cost due to the ineffective use of real estate due to excessive electrode spacing.
Accordingly, there is a continuing need for an electrolyzing method and apparatus whose physical structure impedes the fouling of electrodes, and is otherwise less susceptible to plugging of liquid passage ways. What is also needed is an electrolytic apparatus with close electrode spacing, allowing higher electrical efficiency, while minimizing the undesirable blinding of the current pathway through the liquid solution. What is further needed is an electrolytic apparatus which provides desirable mixing energy throughout the liquid stream, without undesirable high shear. The apparatus should be simple and of low cost design with low maintenance requirements, and the smallest practical footprint size. The present invention fulfills these needs and provides other related advantages.

Method for mixing additives into and electrolyzing contaminated liquids


An aquarium overflow system includes a standpipe with snap-fit mounting constructions, an air vent, air and water apertures, and an adjustable height version.

The invention relates to an aquarium, and more particularly the overflow standpipe.
Aquarium overflow systems are known in the prior art. The overflow system uses a standpipe having an upper inlet receiving water from the aquarium tank and delivering the water to a pump and filter, which water is then returned to the tank.
The present invention evolved during continuing improvements directed to the standpipe construction.


Holding apparatus (100) for electrostatically holding component (1), (e.g., a silicon wafer), includes base body (10) composed of first and second plates (11A,12), the first plate being arranged on upper side (10A) of base body (10) and second plate (12) carrying first plate (11A), and second plate (12) being an electrically insulating material, a plurality of projecting, upper burls (13A) arranged on upper side (10A) and forming a support surface for component (1), and first electrode device (20A) having first electrodes (21A) arranged on upper side (10A) for receiving a clamping voltage, wherein first plate (11A) is produced from electrically conductive, Si-based ceramic and carries upper plate insulating layer (14A) which covers upper side (10A), having upper burls (13A), and the first electrodes (21A) include electrode layers arranged on upper burls (13A) and each carry upper electrode insulating layer (15A). A method for producing the holding apparatus is also described.

The invention relates to a holding apparatus adapted for electrostatically holding a component, in particular a silicon wafer. The invention relates also to a method for producing the holding apparatus. Applications of the invention are in the provision of devices or tools for holding components by means of electrostatic forces, in particular for holding semiconductor components, for example silicon wafers.
Holding apparatuses for holding components electrostatically, which are also referred to as electrostatic holding apparatuses, electrostatic clamping apparatuses, electrostatic clamps, ESCs or electrostatic chucks, are known in general. An important application of electrostatic holding apparatuses is in holding silicon wafers in lithographic semiconductor processing, for example in chip production, in which the particular advantages of electrostatic holding, such as the ease of switching of electrostatic holding or clamping forces, a high positioning accuracy and the reliable fixing of silicon wafers, are exploited.
Typically, an electrostatic holding apparatus has a structure having a plurality of plate-type or layer-type elements that perform differing functions (see e.g. U.S. Pat. No. 4,502,094 or U.S. Pat. No. 8,476,167). At least one plate-type element is equipped with an electrode device with which the electrostatic holding forces are generated. According to U.S. Pat. No. 8,476,167, the electrode device comprises a plurality of electrodes which are embedded between the plate-type elements. Furthermore, an electrostatic holding apparatus typically has at least on its upper side a plurality of projecting upper burls which form a support surface for the silicon wafer.
A conventional electrostatic holding apparatus having embedded electrodes, for example according to U.S. Pat. No. 8,476,167, has the following disadvantages. Because the electrostatic holding force depends on the distance between the silicon wafer and the electrodes, burls having as small a height as possible (e.g. <10 μm) are used to generate a high holding force. However, this leads to an increase in the sensitivity to unwanted particles, which may not find sufficient space between the burls and can impair the planarity of the silicon wafer support. Alternatively, the holding force can be increased by increasing the electrode voltage, but this is associated with risks relating to electrical breakdowns or other faults. Furthermore, because the electrodes are arranged in the spaces between the burls, the silicon wafer that is held can be deformed to an undesirably high degree between the bearing contact points. There can be further disadvantages in relation to the thermal and mechanical coupling of the silicon wafer that is held. For example, the silicon wafer can tend to slip sideways along the extent of the support surface despite a high holding force.
The mentioned disadvantages occur not only in the case of electrostatic holding apparatuses for silicon wafers, but also in the case of holding apparatuses having embedded electrodes for other components, such as, for example, for glass plates having a transparent electrode (ITO), which form AMLCD substrates.

Berliner Glas KGaA Herbert Kubatz GmbH & Co.


A lighting-knob-switch comprises a first light conductor shaped in a cylinder or an oval-top pillar. The first light conductor has a light interceptor (22B) having a concave slope on its rear end and has a lighting face (22A) on its front end. The lighting knob switch further comprises a knob which houses the first light conductor axially, an opening (21C) under the light interceptor (22B) of the first light conductor (22), and a first light emitter (35) under the light interceptor (22B). The light from the first light emitter (35) reflects on the light interceptor (22B) through the opening (21C) and arrives at the lighting face (22A). This construction allows the lighting face (22A) to receive even light at anytime, realizes an easy assembly work, and achieves an inexpensive cost.

A conventional lighting-knob-switch is described by referring to FIG. 8 and FIG. 9. FIG. 8 is a cross section and FIG. 9 is a perspective exploded view of the conventional lighting-knob-switch. In those drawings, a knob 1 made of plastic is engaged with a light conductor 2 made of plastic disposed at the back of the knob 1. A protrusion 2A for lighting disposed at the center of the light conductor 2 is inserted into a center hole 1A of the knob 1. A plate 3 on which a character of the switch mode is drawn is mounted to the protrusion 2A for lighting.
A back-free type box case 4 houses a rotor 5 rotatively, and a first terminal plate 6 is disposed at an open back of the case 4. In front of the first terminal plate 6, a plurality of fixed points 7 are disposed. A rotative shaft 6A, which is a front part of a rotor 5, extends through a hole 4A punched on the front end of the case 4, and a tip of the rotative shaft 5A is engaged and secured with a rotative shaft 2A of the light conductor 2. A press spring 8 and a contact reed 9 are mounted to a back of the rotor 5, where the contact reed 9 is forced to touch elastically the fixed contacts 7 by the press spring 8. A light emitter 10, such as a small bulb or a light emitting diode, is mounted to the back of the light conductor 2. A second terminal plate 11 on which a connector 12 and other electric parts (not shown) are mounted is disposed on a rear side of the bottom plate of the case 4. An elastic lead wire 13 couples the light emitter 10 to the second terminal plate 11, and its center part coils around the rotative shaft 2B in several turns for allowing a rotation of the conductor 2 and the knob 1.
In the above structure, when the knob I is turned, the rotative shaft 2B rotates the rotor 5 via the rotative shaft 5A, and the contact reed 9 mounted on the back of the rotor 5 is forced to elastically touch the fixed contacts 7 and rotates, thus an electrical contact between the plurality of fixed contacts 7 is on and off due to the elastic rotation.
When an electrical signal from an apparatus (not shown) is fed into the light emitter to turn it on via the connector 12, the electrical signal runs through the lead wire 13 and turns on the light emitter 10. The entire light conductor 2 is lit by illumination from the light emitter 10. The light running through the protrusion 2A lights up the switch mode character on the plate 3.
In the above conventional structure, the luminance of the protrusion 2A is likely to be uneven depending on a size of the light conductor 2, because the light emitter 10 mounted at periphery of the light conductor 2 lights up the entire light conductor 2, and thereby illuminating the protrusion 2A. In addition, the center part of the lead wire 13 are coiled around the rotative shaft 2B in several turns, which causes difficulties as well as takes an extra time in an assembly work.

Matsushita Electric Industrial Co., Ltd.


An LSI layout design technique is disclosed which has the ability to satisfy LSI timing constraints in a short processing time. A netlist descriptive of a target circuit that is designed is fed to a computer, and a flip-flop netlist representing information about connections among flip-flops relating to the timing constraints, is generated from the netlist. Such a flip-flop netlist is generated by clustering using a flip-flop as a seed. According to the generated flip-flop netlist, each flip-flop is placed and a flip-flop region to place therein a cell relating to a flip-flop is determined. A cell relating to a corresponding flip-flop is placed in a flip-flop region and the cell arrangement is improved throughout the placement region. Based on the improved cell arrangement, a layout is designed.

This invention relates to LSI layout design technology in the design of large scale integrated (LSI) circuits. It relates particularly to an LSI layout design method capable of meeting timing constraints.
In the layout design of an LSI circuit for use by high-performance information apparatus, a placement of cells is carried out in order of meeting timing constraints which assure the fast clock operation of sync circuits. Such placement, known in the art as a "timing driven placement" becomes important in the layout design of LSI circuits.
A typical timing driven placement method is described. A term for evaluation of the length of a connection line relating to a signal path with the maximum delay (i.e., a critical path) of signal paths in a combinational circuit that has an effect on timing, is added to a function of placement evaluation for circuit area and connection line length evaluation, and the placement of cell is repeatedly improved to minimize the function of placement evaluation.
The above-described method is problematic. In the conventional method, not only timing but also circuit area is evaluated. This will not give a sure guarantee that the timing constraints are satisfied, therefore leading to producing an undesirable placement result with a partial timing constraints violation. Accordingly, in order to meet the timing constraints without fail, it is necessary to repeat a logic design by, for example, re-synthesis after a layout design is carried out.
Since a meticulous placement improvement must be performed to obtain an optimal placement result, associated processing is a time consuming process. It is difficult to improve the efficiency of LSI design.
The inventors of the present invention devised the following method to provide a solution to the problem with the prior art.
Whether timing constraints are satisfied or not is determined by cell placement and wiring between flip-flops that are a critical path beginning and a critical path end, respectively. The inventors paid attention to this point. Connections among flip-flops relating to the timing constraints are found in advance. Subsequently, placement locations for the flip-flops are determined for optimal timing and a layout design is then carried out. In accordance with this method, instead of performing a layout design of a huge number of cells forming an LSI circuit at a time, a layout design of a less number of flip-flops is carried out. This seems to promise not only a considerable reduction of the processing time but also a layout which does meet the timing constraints.
However, the finding of connections among flip-flops relating to the timing constraints is not easy, and it is difficult to represent the found connections in computer readable form.
For example, a case, in which connections among flip-flops are found from a logical-level netlist shown in FIG. 13(a), is explained. In such a case, the found connections will be given in the form of an approximately complete graph, i.e., in the form of a graph in which each node branches out to all the remaining other nodes (see FIG. 13(b)), for a single combinational circuit provides signals to various flip-flops. For this reason, even when trying to determine a placement location for each of the flip-flops for optimal timing, it is not possible to do so.
The fact that the connections form an approximately complete graph means that each flip-flop is in signal input/output relationship with almost all the other flip-flops. On the other hand, for the timing constraints to be met, it is necessary to place flip-flops, which are a signal flow beginning and a signal flow end, in close proximity with each other. For this reason, if the connections (connection relationship) is approximately a complete graph, this makes it possible to bring the flip-flops in close proximity with each other. However, since areas near the flip-flops are finite, this will not guarantee that every flip-flop is placed at its optimal placement location. Accordingly, it is important that the connections will not take an approximately complete graph form.

LSI layout design method capable of satisfying timing requirements in a reduced design processing time


Disclosed herein is an automatic focus control unit including: a first light-emitting element; a line sensor; a second light-emitting element; a slit member; a shifting mechanism; and a controller.

1. Field of the Invention
The present invention relates generally to automatic focus control units and methods for automatically controlling a focal point by positionally adjusting a testing sample and an object lens. In particular, the invention relates to an automatic focus control unit and method, and an electronic device capable of performing focusing depending on an object lens when a plurality of object lenses are switched for use.
2. Description of the Related Art
In the field of optical equipment such as optical microscopes, depth meters, etc., auto focus devices have been used as devices for automatically focusing on a testing sample to be checked.
Examples of the automatic focus devices include one in which a laser beam is directed to a testing sample, a laser beam reflected from the testing sample is detected as the reflected laser beam, the positional relationship with the testing sample is determined based on the reflected laser beam for automatic focusing. This automatic focus device is provided with an optical detector such as a photo diode, which detects the reflected laser beam.
If the automatic focus device as described above is used in an optical microscope, a laser beam is emitted from a light source and directed to a testing sample via an object lens. The laser beam directed via the object lens becomes the reflected laser beam on the testing sample, which is directed to a photo detector via the object lens again.
The reflected laser beam forms on the photo detector a spot corresponding to the distance between the testing sample and the object lens. In the optical microscope mounted with the automatic focus device thereon, the object lens is shifted so that the reflected laser beam may form the spot at a predetermined position on the photo detector. In this way, the optical microscope performs focusing.
Known examples of focal point detecting methods used for microscopes include a knife-edge method, a differential spot-size method, an astigmatism method, a lateral shift method, and a Foucault method. Among them, a technique using the knife-edge method is generally used in the art.
The knife-edge method is a focal point detecting technique which uses a knife-edge mirror and a dual partitioning light-receiving element to perform automatic focusing. For example, as shown in FIG. 12, a laser beam emitted from a semiconductor diode 102 is directed to a testing sample 103 via a collimator lens 106 and via an object lens 101 while the knife-edge mirror 105 shields about half of the optical flux. The laser beam reflected from the testing sample 103 is reflected by the mirror surface of the knife-edge mirror 105 toward the dual partitioning light-receiving element 104. The dual portioning light-receiving element 104 is previously positioned so that the same amount of the reflected laser beam may be directed to two light-receiving sections constituting the dual partitioning light-receiving element 104 while the object lens 101 is focused on the front surface of the testing sample 103.
If the testing sample 103 is out of focus, then the laser beam reflected from the testing sample 103 is offset from an incident position of the dual partitioning light-receiving element 104. This causes a difference between outputs from the two light-receiving elements constituting the dual partitioning light-receiving elements 104. Accordingly, the knife-edge method achieves focusing on the testing sample 103 by shifting the testing sample 103 or the object lens 101 in the optical-axial direction to a position where the outputs from the two light-receiving elements become equal to each other.
Incidentally, in recent years, LCD panels, electronic devices, etc. have been formed with minute circuit patterns and substrates have increasingly been large-sized. Its manufacturing step and checking step have increasingly desired to specify and focus on a test object area with speed and accuracy. To meet the necessity, a parts test under a microscope has been proposed as below. A plurality of object lenses are provided which are different in magnification from each other. A low-power object lens is used when an alignment mark for a large-sized testing sample is detected, whereas a high-power object lens is used when a desired area of the testing sample is checked. That is to say, the object lenses are switched for use depending on the positions or states of a check portion.
In a focal point detecting method using the knife-edge method, however, if the object lens 101 is switched to cause the misalignment of optical axis or color aberration, then the incident position of the dual partitioning light-receiving element 104 will deviate as shown in FIG. 13. This needs such a device as to add a corrective value to the output from the dual partitioning light-receiving element 104 for each of the object lenses 101.
A focal point control method is proposed as a technique for correcting color aberration. In the focal point control method, a focusing error can be corrected even when a color aberration correcting lens is shifted in the optical-axial direction and an object lens having a different color aberration characteristic is used for replacement. This method may need a device for shifting the color aberration correcting lens without the misalignment of optical axis, which may desire high-accurate assembly. In addition, the increased optical parts will enlarge the configuration thereof as well as increase the cost of focal point detecting equipment. Thus, it is difficult to mount the focal point detecting equipment on the traditional, standard microscope.
See Japanese Patent Laid-open Nos. Hei 10-161195 and Hei 11-249027.

Automatic focus control unit, electronic device and automatic focus control method


A semiconductor integrated circuit device of the present invention includes a plurality of banks and a plurality of sense amplifier bands. A switch circuit included in each sense amplifier band receives a signal on a transmission line and outputs a signal read from the bank to a global data input/output line arranged in the column direction. A column bank control circuit for outputting a column bank control signal is arranged on the column decoder side. The column bank control signal is supplied to the transmission line through a column bank control signal line arranged in the column direction. The switch circuit operates in accordance with the column bank control signal. By such a configuration, a column-related operation can be matched easily.

1. Field of the Invention
The present invention relates to a semiconductor memory device and more specifically to a multi-bank system semiconductor memory device.
2. Description of the Background Art
As recent approaches to achieve higher speed of dynamic random access memories (DRAMs), the method of improving the transfer rate of data by accessing the data at a high frequency and the method of improving latency are used.
Since access to row circuitry is especially several times as slow as access to column circuitry in the DRAMs, considerable latency is required when the row circuitry is not activated. In recent years, therefore, the row circuitry has been divided into several banks to increase hit ratio at a row-related activated bank. Thus, such delay in latency as caused by the system has been eliminated and apparent performance of the DRAMs has been improved. The more the number of banks, the higher the performance in this case. However, several drawbacks are caused.
A conventional multi-bank system semiconductor memory device 9000 will be described in the following with reference to FIG. 11. FIG. 11 representatively shows an example where row circuitry is divided into sixteen banks. In the figure, reference numbers 5, 6 and 9 denote a 2-bit global data input/output line, a local data input/output line and a transmission line for transmitting a column bank control signal described below. Further, reference number 8 denotes part of a dividing region 15 described below.
Conventional semiconductor memory device 9000 includes a plurality of banks 10#0, 10#1, 10#2, . . . , 10#15 and a plurality of sense amplifier bands 20#0, 20#1, 20#2, . . . , 20#15, 20#16 and has the configuration of a shared sense amplifier type. The banks can operate independently from one another. The banks each include a plurality of memory cell arrays.
Conventional semiconductor memory device 9000 further includes, a column bank control circuit 100, a column-related control circuit 102, a row-related/row bank control circuit 104 and a row decoder 106.
Column-related control circuit 102 includes a column decoder, a write.read buffer and so on. A read signal from each memory cell array is transmitted from global data input/output line 5 to column-related control circuit 102 and processed.
The sense amplifier bands each include a plurality of sense amplifiers. A read signal from a memory cell is amplified by a sense amplifier and transmitted to local data input/output line 6 that is arranged in the word line direction (row direction).
A signal on local data input/output line 6 is transmitted to global data input/output line 5 that is arranged in the direction of a column selection line (column direction). Global data input/output line 5 is arranged commonly to the same column in a plurality of banks.
Which bank and global data input/output line 5 are connected together is controlled in accordance with a column-related active signal (more specifically, a column bank control signal). Column bank control circuit 100 supplies, in accordance with a column-related bank address, the column bank control signal to transmission line 9 that runs on a sense amplifier band.
Here, the relations between the sense amplifier band and the banks will be described in detail with reference to FIG. 12.
In FIG. 12, bank 10#0 and corresponding sense amplifier band 20#0 are shown as an example. Bank 10#0 includes a plurality of memory cell arrays 12 divided corresponding to a plurality of columns. Memory cell arrays 12 are separated from one another by sub decode bands (in the case of a divided word line configuration) or pile-driven word line regions 15 (in the case of a word line shunt method, the region is hereinafter referred to as dividing regions 15). Here, reference number 4 denotes a bit line pair.
A specific configuration of the sub decode band will be described with reference to FIG. 13. As shown in FIG. 13, the sub decode band (reference number 15 in the figure) includes a plurality of sub decode circuits 16#0, 16#1, 16#2, . . . , 16#i. The sub decode circuits are arranged corresponding to main word lines MWL#0, MWL#1, MWL#2, . . .
Sub decode circuit 16#0 will be representatively described. Sub decode circuit 16#0 includes AND circuits 17#0, 17#1, 17#2 and 17#3. AND circuits 17#2 and 17#3 output, in response to a signal on main word line MWL#0 and a signal on a sub decode line 18, sub decode signals SWL#10 and SWL#11 for one adjacent memory cell array 12.
AND circuits 17#0 and 17#1 output, in response to a signal on main word line MWL#0 and a signal on sub decode line 18, sub decode signals SWL#00 and SWL#01 for the other adjacent memory cell array 12, not shown.
Referring to FIG. 12, sense amplifier band 20#0 includes a sense amplifier 26, a data input/output-related switch circuit 22 and a sense amplifier-related switch circuit 24. Data input/output-related switch circuit 22 and sense amplifier-related switch circuit 24 are arranged in the row direction.
Data input/output-related switch circuit 22 is arranged at a crossing area of a series of dividing regions 15 in the column direction and a sense amplifier band. Data input/output-related switch circuit 22 directly controls connection of global data input/output line 5 and local data input/output line 6 in accordance with column bank control signal CBS received from transmission line 9. Thus, local data input/output line 6 connected to global data input/output line 5 is selected (a bank is selected).
In the multi-bank system, at least two banks may be activated simultaneously during a certain time period. In this case, column access for another bank may be performed while sense amplifier 26 amplifies the fine width of a signal. When column selection line 7 is activated at this time, data on another bank on the global data input/output line is transmitted to sense amplifier 26 and therefore memory cell data is destroyed.
Accordingly, sense amplifier-related switch circuit 24 is provided to directly control connection of sense amplifier 26 and local data input/output line 6 in accordance with column bank control signal CBS received from transmission line 9. Thus, sense amplifier 26 connected to local data input/output line 6 is selected.
A circuit configuration of data input/output-related switch circuit 22 will be described in the following with reference to FIG. 14. In FIG. 14, global data input/output line 5 is formed of global data input/output lines 5a and 5b, and local data input/output line 6 is formed of local data input/output lines 6a and 6b.
Data input/output-related switch circuit 22 includes gate circuits 23a and 23b and an inverter circuit 21. Inverter circuit 21 inverts column bank control signal CBS received from transmission line 9 and outputs a signal/CBS.
Gate circuit 23a is arranged corresponding to global data input/output line 5a and local data input/output line 6a. Gate circuit 23a transmits a signal on local data input/output line 6a to global data input/output line 5a in response to column bank control signal CBS and signal/CBS.
Gate circuit 23b is arranged corresponding to global data input/output line 5b and local data input/output line 6b. Gate circuit 23b transmits a signal on local data input/output line 6b to global data input/output line 5b in response to column bank control signal CBS and signal/CBS.
In this manner, local data input/output line 6 connected to global data input/output line 5 is selected by column bank control signal CBS corresponding to a bank.
A specific configuration of sense amplifier-related switch circuit 24 will be described in the following with reference to FIG. 15. FIG. 15 also shows the relations with sense amplifier 26.
Sense amplifier-related switch circuit 24 includes NMOS transistors N2a, N2b, N3a and N3b. NMOS transistors N3a and N3b constitute a column selection gate 25.
NMOS transistors N2a and N3a are connected in series between local data input/output line 6a and sense amplifier 26. NMOS transistors N2b and N3b are connected in series between local data input/output line 6b and sense amplifier 26.
NMOS transistors N2a and N2b have their gate electrodes connected to transmission line 9. NMOS transistors N3a and N3b have their gate electrodes connected to column selection line 7.
Column selection gate 25 is opened and closed in response to a signal on column selection line 7. NMOS transistors N2a and N2b are turned on/off in response to column bank control signal CBS received from transmission line 9.
Column selection line 7 selects memory cell array 12 in the column direction, and column bank control signal CBS selects sense amplifier 26 connected to local data input/output line 5.
However, the operation cycle of the column-related circuitry side is several times as fast as that of the row-related circuitry side. In the configuration of the above described conventional semiconductor memory device 9000, therefore, the column bank control signal CBS is transmitted from the row-related circuitry side and thus the timing of the row-related circuitry and column-related circuitry sides is difficult to match. Accordingly, the configuration is not suitable for a high speed operation.
Further, transmission line 9 for transmitting the column bank control signal CBS has a considerable load. In the case of a one-directional input (input in the row direction) from column bank control circuit 100, therefore, the speed of signal transmission is different between switch circuits (the sense amplifier-related switch circuit and the data input/output-related switch circuit) closest to the row decoder and switch circuits farthest from the row decoder. Thus, achievement of higher operating speed is hindered.

Multi-bank system semiconductor memory device capable of operating at high speed


A method for forming a CMOS device in a manner so as to avoid dielectric layer undercut during a pre-silicide cleaning step is described. During formation of CMOS device comprising a gate stack on a semiconductor substrate surface, the patterned gate stack including gate dielectric below a conductor with vertical sidewalls, a dielectric layer is formed thereover and over the substrate surfaces. Respective nitride spacer elements overlying the dielectric layer are formed at each vertical sidewall. The dielectric layer on the substrate surface is removed using an etch process such that a portion of the dielectric layer underlying each spacer remains. Then, a nitride layer is deposited over the entire sample (the gate stack, the spacer elements at each gate sidewall, and substrate surfaces) and subsequently removed by an etch process such that only a portion of said nitride film (the “plug”) remains. The plug seals and encapsulates the dielectric layer underlying each said spacer, thus preventing the dielectric material from being undercut during the subsequent pre-silicide clean process. By preventing undercut, this invention also prevents the etch-stop film (deposited prior to contact formation) from coming into contact with the gate oxide. Thus, the integration of thin-spacer transistor geometries, which are required for improving transistor drive current, is enabled.

The present invention relates to complementary metal oxide semiconductor (CMOS) devices, and more particularly to a process and structure for forming a metal oxide semiconductor field effect transistor (MOSFET) implementing thin sidewall spacer geometries.
FIGS. 1(a)–1(e) depict cross-section views of a portion of a semiconductor device manufactured in accordance with conventional processing techniques. As shown in FIG. 1(a), a semiconductor device 10 is formed on a wafer. The device includes a substrate 12 and a patterned gate stack 15 formed thereon. Each patterned gate stack 15 may be formed of a gate material such as polycrystalline silicon, for example, and as conventionally known, the gate 15 is formed on a thin gate dielectric layer 20 previously formed on top of the substrate 12. Prior to the formation of low resistivity cobalt, titanium, or nickel silicide contacts with active device regions 16, 18 and gate 15 of the semiconductor device 10, thin nitride spacers are first formed on each gate sidewall. Typically, as shown in FIG. 1(a), a dielectric etch stop layer 25, ranging from about 10 Å–300 Å in thickness, but preferably 50 Å–150 Å, is first deposited on the thin gate oxide layer 20 over the substrate surfaces and the patterned gate stack 15. While this dielectric etch stop prevents recessing of the substrate during reactive ion etching (RIE) of the spacer, it has the disadvantage of being susceptible to removal or undercut during the extensive preclean that must be utilized prior to silicide formation.
Then, as shown in FIG. 1(b), an additional dielectric layer 30 is deposited on the patterned gate stack and active device regions. This additional dielectric layer is typically formed of a nitride material.
While this dielectric etch stop prevents recessing of the substrate during spacer RIE, it has the disadvantage of being susceptible to removal or undercut during the extensive pre-clean that must be utilized prior to silicide formation.
As shown in FIG. 1(c), a RIE process is performed, resulting in the formation of vertical nitride spacers 35a, 35b on each gate wall. Prior to metal deposition, which may be titanium, cobalt or nickel, a lengthy oxide strip process is performed to prepare the surface for the silicide formation. This oxide strip is crucial to achieving a defect free silicide. However, as illustrated in FIG. 1(d), the problem with this lengthy oxide strip is that the dielectric etch stop beneath the spacers 25 becomes severely undercut at regions 40a, 40b. The resultant oxide loss or undercut gives rise to the following problems: 1) the barrier nitride layer 50 that is ultimately deposited, as shown in FIG. 1(e), will be in contact with the gate dielectric edge 17 thus degrading gate dielectric reliability; 2) the silicide in the source/drain regions 60a,b (not shown) may come into contact with the gate dielectric at the gate conductor edge, which would create a diffusion to gate short); and, 3) the degree of undercut will vary significantly from lot to lot. These aforementioned problems are particularly acute for transistors with the thin spacer geometries required for(which becoming continued CMOS scaling.
Thin sidewall spacer geometries are becoming increasingly important aspects of high performance MOSFET design. Thin spacers allow the suicide to come into close proximity to the extension edge near the channel, thereby decreasing MOSFET series resistance and enhancing drive current. The implementation of a spacer etch process (specifically RIE) benefits substantially from an underlying dielectric layer (typically oxide) beneath the nitride spacer film. This dielectric serves as an etch stop for the nitride spacer RIE. Without this etch stop in place, the spacer RIE would create a recess in the underlying substrate, degrading the MOSFET series resistance, and in the case of thin SOI substrates, reducing the amount of silicon available for the silicide process.
In order to avoid the problems associated with thin spacer geometries on thin SOI, it would be extremely desirable to provide a method for avoiding the oxide undercut when performing the oxide removal step during the pre-silicide clean.

Method for avoiding oxide undercut during pre-silicide clean for thin spacer FETs

International Business Machines Corporation


A method of preparing a semiconductor device, comprising: forming an amorphous silicon layer on a substrate, and applying shots of an excimer laser beam to the amorphous silicon layer to convert the amorphous silicon layer into a polysilicon layer having a plurality of silicon grains, each of the grains having a grain size and including a crystallite having a crystallite size on the (111) plane, an average value of the crystallite sizes on the (111) plane of the crystallites included in the polysilicon layer being sixty percent or greater of an average value of the grain size.

1. Field of the Invention
The present invention relates to a semiconductor device, such as a thin-film transistor, having in its main part a polysilicon thin film for transferring carriers.
2. Description of the Related Art
A technique of forming a thin-film transistor on an insulating substrate is known in the field of active matrix liquid crystal displays (LCDs). The technique allows a semiconductor integrated circuit to be formed on a transparent insulating substrate formed of, for example, glass, or a large insulating substrate which cannot be formed of a monocrystalline semiconductor. At present, a thin-film transistor generally includes an active layer made of amorphous silicon o r polysilicon. Since amorphous silicon can be formed at a low temperature, it is applicable to an active matrix LCD which must be formed on a glass substrate having a low melting point.
However, since amorphous silicon has a low electron mobility, it has been used only as a switching element for charging a pixel capacitor electrode to apply an electric field to a liquid crystal. An active layer made of polysilicon must be used in a circuit element, e.g., a driver circuit, a ROM, a RAM or a CPU, which must be driven at a high speed. For example, a driver circuit of a high-quality, large-screen liquid crystal TV or a high-definition office automation (OA) liquid crystal display panel is driven at a clock frequency of about 10 MHz. If such a driver circuit is formed of a semiconductor device, a field effect mobility .mu..sub.FE of 50 cm.sup.2 /V.multidot.sec or more, preferably 80 cm.sup.2 /V.multidot.sec or more is required. However, the field effect mobility .mu..sub.FE of a polysilicon thin-film transistor known to the public at present is at most 30 cm.sup.2 /v.multidot.sec.

Method of producing a semiconductor device


A mold for manufacturing products made of composite materials, which comprises at least one functional portion made of a composite material joined to at least one interface made of a composite material which projects at least partially around the functional portion, said mold being provided with one or more mechanic fastening devices for the coupling with at least another mold.

The known RTM (Resin Transfer Molding) process employs molds made of steel for withstanding the high pressures, even higher than 15 bar, needed for the injection of the resin.
The shaping of the fiber layers and their subsequent deposition into the molds can be automated, thus making more repeatable and economic the parts produced with this process, however the molds of the RTM process are heavy, expensive and bulky. Moreover, the metal molds need a complex design which must take their thermal expansion into account during the curing cycle of the resin, to avoid the molded product being clogged inside a mold.
The RTM-Light process, in which a semirigid mold is arranged on a rigid mold, is known for overcoming these technical problems. The resin is injected at a pressure lower than 1 bar and air (0.5 bar) is sucked from a central low point for favoring the flowing of the resin. The joining between the two molds is obtained by creating vacuum (0.1 bar) along the edges of the two molds. This process, though it is simple to be carried out with light and economic devices, does not allow to manufacture products with the same speed and the same quality of the RTM process, since the injection pressure is relatively low and the side of the product facing the semirigid mold has a rough finish. Furthermore, the low pressure employed in the RTM-Light process does not ensure the correct and complete impregnation of the dry fibers, thus causing the manufacture of low quality components.
EP 1721719 and FR 2864801 disclose RTM processes in which the molds are made of composite materials. In particular, the molds disclosed in FR 2864801 are in turn made by means of a RTM process in which the resin is injected only after the fibers have been arranged between a mold made of a composite material and a master or a template. These known molds are relatively expensive due to the RTM process employed for their manufacturing and to the need of arranging a template between a first mold which is already ready and a second mold during the manufacturing of the latter. The known molds made of a composite material further require complex supporting structures and/or must be relatively thick, thus expensive, for withstanding the pressures of the RTM process.

Mold made of a composite material and process employing this mold


A method includes receiving a query from an external entity for information about a call between a first user and a second user, determining a call identifier associated with the call and providing the call identifier to the external entity. Subsequently, when a request to alter the call and comprising the call identifier is received from the external entity, the call is altered the call in accordance with the request.

Existing web services, such as Parlay X MakeCall can be used to make a call from a first telephone to a second telephone, to add additional parties to the call or to add other media to existing calls, such as video media. However, in all such cases the call must be initiated from a web service interface in order to get a reference call identifier (CallID) number from the call server implementing the desired service. Subsequent actions, such as adding video to the call, are performed using the reference CallID. It is not possible with existing web services to modify or control a call that was not established by the web service such as standard voice calls placed from a first party to a second party.
Given the emergence of standards such as GSMA VideoShare, ImageShare and Rich Communication Suite (RCS), as well as the growing adoption of solutions combining multiple user devices (e.g., phone+computer, phone+TV, etc.), there is a need for a method enabling the addition of media and/or functionality to standard voice calls.


A hand-held cutter with automatic blade changer which has a casing, short blades each with an aperture, a pushbutton and a plug, and the casing is composed of an outer casing, a fixed blade holder and a retractable blade holder; and it further has a blade changer which is divided into a blade unloading chamber and a blade loading chamber. The present invention has the advantages of being simple in construction and convenient to use, and allowing the users to change and dispose of the blades without touching them, thereby effectively protecting personal safety.

The present invention relates to a hand-held cutting tool and more particularly pertains to a hand-held cutter with automatic blade changer.
Hand-held cutters are generally classified into two categories, namely, for stationery purposes and for industrial purposes. Hand-held cutters for stationery purposes are office or student supplies for cutting sheets of paper. The blade for such a cutter is in the form of a strip. On the surface of the blade, a plurality of evenly spaced straight grooves is cut so that after the foremost pointed end of the blade has become blunt, the blunt pointed end of the blade can be bent and broken at the foremost groove, thereby allowing continuous use of the next sharp pointed end of the blade. When the whole strip of the blade is used up, it can be replaced by a new strip. However, the process of bending, breaking and changing must be operated by hand, and if sufficient care is not taken, the user's fingers may easily be injured. Further, during the process of bending and breaking, the blunt end of the blade may spring out causing injuries. Improper disposal of the discarded blunt end of the blade may also easily cause accidents. These are particularly dangerous to school children.
Hand-held cutters for industrial purposes are used for cutting thicker and harder objects such as carpets and wallpaper. They are also used in woodworking, engraving, etc. The blades are shorter, thicker and in the form of a trapezoid. As the blades are more dangerous, the cutters are usually disposed with safety means to secure the blades in position. Nevertheless, the method of bending, breaking and continuous use of the blades cannot be applied to industrial cutters. Therefore, changing of the blades must be accomplished by hand piece by piece while the safety means makes it difficult to change the blades.
The prior art provides cutters with a plurality of blades stored inside the body of the cutters for replacement. However, this increases the size and weight of the cutters, which is not favorable to the cutters' basic characteristics of being hand-held tools. Furthermore, most of the changing of the blades is operated by hand and that is not safe enough. Although the prior art also provides cutters capable of automatic changing of blades, their construction is more complicated, and the cutters are composed of a plurality of parts and components so the costs of production are higher. The cutters are larger in size and heavier in weight, and are not convenient to use. Disposal of the blunted blades is still required to be operated by hand and it is not sufficiently safe.

Hand-held cutter with automatic blade changer


Methods and apparatus for time synchronization and measurement of power distribution systems. A method includes receiving a synchronized wireless communication signal, synchronizing to the synchronized wireless communication signal to produce synchronized time, performing one or more power distribution measurements based on the synchronized time to produce synchronized power distribution measurements, and transmitting the synchronized power distribution measurements to a power control center. An apparatus includes a receiver configured to receive a synchronized wireless communication signal and to synchronize to the synchronized wireless communication signal to produce synchronized time, a measurement module configured to perform one or more power distribution measurements based on the synchronized time to produce synchronized power distribution measurements, and a transmitter configured to transmit the synchronized power distribution measurements to a power control center.

1. Field
The present application relates generally to the operation of power distribution systems, and more particularly, to methods and apparatus for time synchronization and measurement of power distribution systems.
2. Background
The electricity industry is going through a metamorphosis with utilities rolling out what is known as the "Smart Grid". The "Smart Grid" is an intelligent, managed, controlled, network communication overlay on top of the existing electric distribution network. Essentially the Smart Grid links utility computer servers to grid infrastructure devices and new "smart electricity meters." Several Smart Grid services require that precise time be known. For example, synchronized phasor measurements (time-stamped measurements of alternating current phase), Time of Use (TOU) metering, and scheduled load shedding are just a few of these services.
However, determining precise synchronized time across the smart grid can be challenging and expensive. Some higher end utility infrastructure components use Global Positioning System (GPS) modules to maintain precise time, but these modules are too expensive to be deployed in individual smart meters. Thus, smart meters must use other, less accurate and less expensive, means of acquiring and maintaining time.
Typically, smart meters use the power line frequency itself to measure the passing of time, filling in with expensive real-time clock components to cover power outages. Unfortunately, this adds significant cost to the meter, and time accuracy errors tend to accumulate over periods of usage. The result is that time in smart meters is nowhere near accurate enough to enable synchronized phasor measurements, and it is barely adequate for Time of Use metering.
Therefore, it would be desirable to have a simple cost effective mechanism that operates to provide time synchronization and measurement for improved monitoring and failure detection for power distribution systems.


In a cable assembly, when auxiliary ground conductor is provided so as to face the lower surface of supporting insulating member, elastically-deformed piece in an elastically deformed status comes in contact with the tip of ground terminal protruding from the lower surface of supporting insulating member.

The Present Disclosure relates, generally, to a cable assembly, connector and semiconductor tester, and, more particularly, to technology that improves signal transmission properties.
A connector into which a co-axial cable is inserted and which electrically connects the co-axial cable and an electronic device has traditionally been known. For such cables, a co-axial structure in which a ground conductor surrounds a signal conductor has been utilized, in which the ground conductor blocks electromagnetic waves. An example is disclosed in Japanese Patent Application No. 2007-065754, the content of which is also incorporated herein in its entirety.
Incidentally, on the tip of the co-axial cable, a signal terminal and a ground terminal, utilized to connect to a signal terminal and a ground terminal so that the co-axial cable is connected to the terminals of the other side, are provided. On the tip, the ground terminal preferably takes a co-axial constitution surrounding the signal terminal.
However, due to a demand to improve the density of terminals, it is sometimes difficult to utilize a co-axial structure in which the ground terminal surrounds the signal terminal. Because of this, the signal transmission properties might be deteriorated.

Coaxial cable member coupled to a signal terminal, a ground terminal and an auxiliary ground conductor with an elastically-deformable piece


The invention relates to handover of a mobile station (12) from a source cell to a target cell when the identity of the target cell in a wireless communication network (10, 11) is ambiguous, a source base station (14) defining the source cell receives an event from the mobile station comprising a cell identifier, investigates if there are more cells in the neighborhood sharing the same cell identifier and sends a handover instruction to the mobile station comprising an identity ambiguity indicator if there are more cells sharing the same cell identifier. The mobile station autonomously initiates establishment of a connection to a target base station defining the target cell based on the identity ambiguity indicator in order to effect handover.

One trend in mobile communication networks is that they are becoming more and more heterogeneous. This means that the base stations and the cells they provide vary considerably. There may here be macro cells covering large areas combined with much smaller pico cells covering hot spots. A macro base station does typically transmit with much higher power than a pico cell and hence provides much larger cells. In addition to this it is possible that the networks also includes femto cells, where the base stations that provide these cells are even smaller and transmit with even lower power levels. These cells are often provided domestically or in households.
As a mobile station is moving in such a network, it is common to hand it over from one cell to another. In order to be able to perform handover, the cells have to be possible to identify. For this reason the cells are provided with cell identifiers. The identifiers used for handover are then often shared by several cells, i.e. not unique. However, the re-use of cell identifiers has traditionally been such that the cells that share the same identifier are provided at long distances from each other and therefore the same identifier should not appear in cells within the same neighbourhood. This is typically done by the operator in network planning.
Now with the introduction of pico and femto cells, this may not be possible any more. There may be so many cells that several pico cells may use the same cell identifier in the vicinity of a macro cell. There may here be even more femto cells in a neighbourhood.
Furthermore, a network operator may also have no real control of where a femto cell is placed. Therefore also several of these may have the same non-unique cell identifier.
Since it is possible for a target cell, i.e. a cell to which a mobile station may need to be handed over, to share a cell identifier with other cells, there may occur problems when performing handover from a source cell, i.e. a cell with which a mobile station is actively communicating.
One way to handle this is described in WO 2008/113373, where a forced handover command is used by the source base station to command a mobile station to perform handover to a target base station for which a cell global identifier is not known in the source base station. The source base station also provides information about its own cell global identifier to the mobile station that forwards the information to the target base station. Target and source base station may then communicate for effecting handover.
Another way to address this is to be found in 3GPP TS 36.300 in a procedure called "inbound mobility to E-UTRAN CSG cells". Here principles similar to Automatic Neighbour Relation (ANR) are applied for letting the mobile station provide more information to the source cell to uniquely identify the target cell.
This type of activity functions well. However, there is still room for improvement when performing handover to a cell with non-unique cell identifier.

Handover in relation to cell identity ambiguity


Disclosed is a security astragal that is secure against unauthorized removal but can be easily removed when authorized so that the door can be subsequently reused without the astragal. The disclosed security astragal includes a security bar that protects against tampering with the door latching mechanism and a protective sheath that secures the security bar from unauthorized removal.

Double entrance doorways are commonplace in residential and business settings. Typically, one door in a double doorway remains closed and is referred to as the inactive leaf. The other door, commonly referred to as the active leaf, is used as the main entrance door. Generally, the mating edges of the active and inactive doors do not directly contact each other, but are separated by a slight gap. This gap, when exposed, provides room for tampering with the door latching mechanism.
An astragal's primary function is to cover the gap between double doors and thus secure the door latching mechanism. Typically, an astragal is attached along the exterior edge of the inactive door so as to cover the gap between the active and inactive door leaves.
FIG. 1 depicts a standard double door arrangement employing a prior art astragal 10. As shown, an astragal 10 is affixed to and runs the length of the inactive leaf 12. When the active leaf 14 is in the closed position, the astragal 10 functions to cover the gap between the active 14 and inactive 12 leaves so as to prevent tampering with the door latching mechanism.
FIG. 2 depicts a partial view of a typical inactive door leaf 12 with an attached astragal 10. As shown, the astragal 10 overlaps the edge of the inactive leaf 12. The overlap is large enough to bridge a gap that may exist between the inactive 12 and active 14 leaves when both are in the closed position. By bridging the gap between the door leaves, the astragal protects the latching mechanism from compromise.
A problem not addressed by the prior art is securing the astragal against unauthorized removal while also providing the flexibility for quick and easy authorized removal. One prior art method of attaching an astragal is to drill anchoring screws through the exterior face of the astragal. An astragal attached in this fashion serves the purpose of obstructing attempts to manipulate the latching mechanism between doors. However, an astragal attached with exposed anchoring screws could potentially be removed without authorization by unscrewing the exposed screws. Unauthorized removal of the astragal would leave the latching mechanism exposed to potential tampering.
Another prior art method of securing an astragal is to weld the astragal to the door. Generally, the welded bonds between the door and the astragal are permanent and cannot be broken. Although welding assures against unauthorized removal of the astragal, it also precludes the astragal from being removed so that the door can be reused without the astragal. Similar techniques of permanently affixing an astragal to the door also assure against unauthorized removal but likewise preclude authorized removal and subsequent reuse of the door without the astragal.
Accordingly, a primary goal of the present invention is to provide a security astragal that is secure against unauthorized removal but which permits authorized removal and subsequent reuse of the door without the astragal.


An automatic document feeder includes an outer casing, an upper cover, a first pressing roller set and a separating device. The first pressing roller set is installed in a receiving member, which is arranged at a terminal side of the outer casing. The first pressing roller set includes a first rotating shaft and a first pressing roller. The separating device is sheathed around the first rotating shaft and exposed outside the receiving member. When the upper cover is opened, the upper cover is contacted with the separating device, so that the separating device is moved to shift the first rotating shaft.

An office machine such as a multifunction peripheral and an image scanning apparatus becomes an essential electronic device in the office. For successively feeding many paper sheets to increase the scanning speed, the multifunction peripheral and the image scanning apparatus are usually equipped with an automatic document feeder.
FIG. 1A is a schematic cross-sectional view illustrating a conventional automatic document feeder, which is disclosed in Taiwanese Patent No. TWI255253. As shown in FIG. 1A, the automatic document feeder 1 comprises an outer casing 11, an upper cover 12, a first relay roller 13, a second relay roller 14, a lever 15, a paper guide casing 16 and a paper pick-up module 17. A first end of the lever 15 is connected with the first relay roller 13. A second end of the lever 15 is sustained against a downward protrusion 121 of the upper cover 12. The middle portion of the lever 15 is fixed on a rear side of the first relay roller 13 through a fixing structure 151.
During a scanning operation is performed, the paper sheet to be scanned is transported through the paper guide casing 16 by the paper pick-up module 17, and then the paper sheet is pressed and clamped between the first relay roller 13 and the second relay roller 14 to be fed into internal portion of the automatic document feeder 1.
In a case that the paper sheet is jammed, the upper cover 12 should be uplifted to remove the jammed paper sheet, and then another paper sheet can be fed again to perform the scanning operation. FIG. 1B is a schematic enlarged fragmentary view illustrating a dotted circled portion of the automatic document feeder of FIG. 1A. Hereinafter, the action of the automatic document feeder for removing the jammed paper sheet will be illustrated with reference to FIG. 1B. Firstly, the upper cover 12 is rotated in the directional. Correspondingly, the second end of the lever 15 is pushed by the protrusion 121 of the upper cover 12, and the lever 15 is rotated in the direction a2 by using the middle portion of the lever 15 as a fulcrum. As the lever 15 is rotated in the direction a2, the first relay roller 13 is correspondingly moved in the direction a3, so that the first relay roller 13 is separated from the second relay roller 14. Meanwhile, the jammed paper sheet may be pulled out of the automatic document feeder 1 without difficulty.
From the above discussions, in the conventional automatic document feeder 1, the jammed paper sheet may be removed when the upper cover 12 is opened and the first relay roller 13 is separated from the second relay roller 14 through the lever 15.
The conventional automatic document feeder 1, however, still has some drawbacks. For example, since the lever 15 is fixed on the rear side of the first relay roller 13 through the fixing structure 151 and the lever 15 is sustained against the protrusion 121 of the upper cover 12, it is necessary for the conventional automatic document feeder 1 to provide an additional space to accommodate the lever 15 in order to achieve the function of removing the jammed paper sheet. As shown in FIG. 1, since there is an additional space at the rear side of the first relay roller 13, the overall volume of the conventional automatic document feeder 1 is increased.
Therefore, there is a need of providing an improved automatic document feeder so as to obviate the drawbacks encountered from the prior art.


A thermocouple connector adapted to an electromagnetic valve, the electromagnetic valve having a quick-connect terminal with a base. The connector has an inner surface that faces the base when the connector is inserted transversally to the connection terminal. The connector includes guiding means that projects out in relation to the inner surface, extending longitudinally in the direction of insertion, adapted to guide the transverse insertion of the connector. The connector is configured to come into contact with the base through the guiding means.

There are known fusion-type, quick-connect thermocouple connectors, adapted to be connected to electromagnetic valves adapted to a gas apparatus, which also comprise quick connector terminals.
Document EP1707879B1 describes a connection of a thermocouple that has two integrated connectors, one earth connector and one phase connector, of the thermocouple in a connector body, it being adapted for the connection to a thread of the electromagnetic valve and to a quick-connect terminal of the electromagnetic valve, the connection being inserted transversally to the electromagnetic valve.
In addition, document EP691510A1 describes an adaptor for allowing the electrical connection of a thermocouple with a quick-connect connector to different types of connection terminals of the electromagnetic valves. The adaptor comprises on one end a quick-connect terminal that has a head that is retained by the connector. The connector is inserted transversally to the connection terminal. The terminal comprises a base and retainer means that extend continuously from the base to form lobes that retain the head against the base, establishing electrical contact between the thermocouple and the electromagnetic valve.
One of the drawbacks associated with this type of connector is that the operator has to exert considerable force in order to insert the connector in the quick-connect terminal of the valve, especially in view of the fact that they have to insert various connectors.

Thermocouple connector adapted to an electromagnetic gas valve, and thermocouple comprising the connector


In some embodiments of the invention, an 802.11-enabled device may fragment an 802.11 packet into smaller packets and transmit the smaller packets instead of the 802.11 to lessen interference with Bluetooth synchronized connection-oriented communication of a collocated Bluetooth-enabled device.

Certain standards for wireless communication that were developed by separate standardization bodies use overlapping frequency bands. For example, both the 802.11 specifications for Wireless LAN Medium Access Control (MAC) and Physical layer (PHY), developed by the Institute of Electrical and Electronics Engineers (IEEE) and the Bluetooth® core specifications v1.1 published by the Bluetooth® special interest group (SIG) operate in the 2.4 gigaHertz (GHz) frequency band.
Wireless communication compatible with one of these standards may interfere with collocated wireless communication compatible with another of these standards.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity.

Apparatus and methods for coexistence of collocated wireless local area network and bluetooth® based on dynamic fragmentation of WLAN packets