Within each of: (1) a method for inspecting a reticle; (2) an apparatus for inspecting the reticle; and (3) a method for forming a microelectronic layer while employing the method for inspecting the reticle and the apparatus for inspecting the reticle, there is employed a pair of wedges whose inclined surfaces are counter-opposed and separated by a gap. The pair of wedges whose inclined surfaces are counter-opposed and separated by the gap is employed in conjunction with an inspection light source and detector for determining an optimizing an optical characteristic of the reticle, such as an optimized optical interference characteristic of the reticle, such that the reticle may be optimally aligned within a photoexposure apparatus and there may be formed with optimal registration while employing the reticle and the photoexposure apparatus a microelectronic layer within a microelectronic fabrication.

1. Field of the Invention
The present invention relates generally to reticles employed when fabricating microelectronic fabrications. More particularly, the present invention relates to methods and apparatus for inspecting reticles employed when fabricating microelectronic fabrications.
2. Description of the Related Art
Microelectronic fabrications are formed from microelectronic substrates over which are formed patterned microelectronic conductor layers which are separated by microelectronic dielectric layers.
As microelectronic fabrication integration levels have increased and microelectronic device and patterned microelectronic conductor layer dimensions have decreased, it has become increasingly important when fabricating microelectronic fabrications to assure optimal registration of various overlying microelectronic layers which may be employed when fabricating a microelectronic fabrication.
While assuring optimal registration of various overlying microelectronic layers which may be employed when fabricating a microelectronic fabrication is thus clearly of significance and importance when fabricating a microelectronic fabrication, assuring optimal registration of various overlying microelectronic layers which may be employed when fabricating a microelectronic fabrication is nonetheless not entirely without problems in the art of microelectronic fabrication. In that regard, it is often recognized in the art of microelectronic fabrication that optimal registration of various overlying layers which may be employed when fabricating a microelectronic fabrication may be influenced by multiple interrelated and obscure factors derived from interactions between a photoexposure reticle and a photoexposure apparatus.
It is thus in general towards the goal of providing optimal registration of various overlying layers which may be employed when fabricating a microelectronic fabrication that the present invention is generally directed. Similarly, it is thus more particularly towards the goal of providing an efficient method for inspecting a reticle such as to provide optimal registration of an overlying layer which may be employed when fabricating a microelectronic fabrication while employing the reticle that the present invention is more specifically directed.
Various methods and apparatus have been disclosed in the art of microelectronic fabrication for inspecting reticles employed within the art of microelectronic fabrication.
For example, Noguchi et al., in U.S. Pat. No. 5,098,191, discloses a method for inspecting a reticle and a related apparatus for inspecting the reticle, wherein only foreign substances and defects which actually produce damage when employing the reticle incident to forming a microelectronic layer for use within a microelectronic fabrication are detected. To realize the foregoing object, the method for inspecting the reticle and the apparatus for inspecting the reticle employ a comparison of an inspected reticle in conjunction with a standard reticle with respect to reflected illuminating inspection light characteristics and transmitted illuminating inspection light characteristics.
In addition, Emery et al., in U.S. Pat. No. 5,737,072, discloses a method for inspecting a reticle and a apparatus for inspecting the reticle, wherein the method for inspecting the reticle and the apparatus for inspecting the reticle need not employ a standard reticle for comparison purposes when inspecting the reticle while employing the method for inspecting the reticle and the apparatus for inspecting the reticle. To realize the foregoing result, defect detection within the reticle is determined while employing the method for inspecting the reticle and the apparatus for inspecting the reticle by comparing combinations of at least two inspection light transmission signals or light reflection signals which are measured or derived while employing the method for inspecting the reticle and the apparatus for inspecting the reticle.
Desirable in the art of microelectronic fabrication are additional methods and apparatus which may be employed for inspecting reticles employed for fabricating microelectronic fabrications, particularly as regards inspecting reticles such as to assure optimal registration of overlying layers within microelectronic fabrications which are fabricated while employing the reticles.
It is towards the foregoing object that the present invention is directed.
A first object of the present invention is to provide a method for inspecting a reticle and an apparatus for inspecting the reticle.
A second object of the present invention is to provide the method for inspecting the reticle and the apparatus for inspecting the reticle in accord with the first object of the present invention, wherein the method for inspecting the reticle and the apparatus for inspecting the reticle provide for optimal registration of an overlying layer within a microelectronic fabrication fabricated employing the reticle.
A third object of the present invention is to provide the method for inspecting the reticle and the apparatus for inspecting the reticle in accord with the first object of the invention and the second object of the invention, which method and apparatus are readily commercially implemented.
In accord with the objects of the present invention, there is provided by the present invention a method for inspecting a reticle and an apparatus for inspecting the reticle. To practice the method for inspecting the reticle, there is first provided a reticle comprising a transparent substrate having formed thereupon a patterned non-transparent layer which defines an alignment mark. There is then impinged at a non-orthogonal angle through the alignment mark within the reticle an inspection light beam which is both: (a) refracted and transmitted directly through the reticle; and (b) refracted, reflected and then transmitted through the reticle, to thus provide a multiplicity of refracted transmitted inspection light beams. There is then passed the multiplicity of refracted transmitted inspection light beams through a pair of wedges whose inclined surfaces are counter-opposed and separated by a gap to form a multiplicity of additionally refracted transmitted inspection light beams. Finally, there is then varied a distance of the gap to optimize an optical characteristic of the additionally refracted transmitted inspection light beams.
Optionally, the method for inspecting the reticle may also further comprise correlating a variation of the distance of the gap to a variation of the non-orthogonal angle to provide a varied non-orthogonal angle which alternatively optimizes an optical characteristic of the additionally refracted transmitted inspection light beams.
The method for inspecting the reticle in accord with the present invention contemplates an apparatus for inspecting the reticle in accord with the present invention.
In addition, the method for inspecting the reticle in accord with the present invention also contemplates a method for aligning the reticle within a photoexposure apparatus in accord with the present invention.
The present invention provides a method for inspecting a reticle and an apparatus for inspecting the reticle, wherein the method for inspecting the reticle and the apparatus for inspecting the reticle provide for optimal registration of an overlying layer within a microelectronic fabrication fabricated employing the reticle. The method for inspecting the reticle and the apparatus for inspecting the reticle in accord with the present invention realize the foregoing object by employing with respect to a multiplicity of refracted transmitted inspection light beams derived from an inspection light beam incident non-orthogonal to a reticle at the location of an alignment mark within the reticle a pair of transparent wedges whose inclined surfaces are counter-opposed and separated by a gap a distance of which is varied to optimize an optical characteristic of a series of additionally refracted transmitted inspection light beams derived from the series of refracted transmitted inspection light beams. Similarly, within the method for inspecting the reticle and the apparatus for inspecting the reticle of the present invention there is optionally correlated a distance of the gap with a variation of the non-orthogonal angle in a fashion which alternatively optimizes the optical characteristic of the additionally refracted transmitted inspection light beams and thus contributes to enhanced alignment of the reticle within a photoexposure apparatus and thus enhanced registration of a microelectronic layer formed within a microelectronic fabrication while employing the reticle and the photoexposure apparatus.
The method for inspecting the reticle and the apparatus for inspecting the reticle are readily commercially implemented. The method for inspecting the reticle in accord with the present invention and the apparatus for inspecting the reticle in accord with the present invention employ sub-methods, materials and components as are generally known in the art of microelectronic fabrication, but employed and/or fabricated in a fashion which provides the present invention. Since it is thus a specific configuration of process steps and/or components which provides at least in part the present invention, rather than the existence of methods, materials and components which provides the present invention, the method of the present invention and the apparatus of the present invention are readily commercially implemented.

Method for inspecting a reticle and apparatus for use therein

Taiwan Semiconductor Manufacturing Co., Ltd


An endoscope has a handle and a bendable tube extending distally away from the handle. The tube has a selectively deflectable distal segment. An activating wire is connected to the distal segment and to the handle, and the handle has a knob which can be turned to impart force to the wire and thereby cause the distal segment of the tube to deflect. The wire is held by a hypotube column support which is attached to the handle and to the deflectable distal segment, such that when the knob is turned, the column support transfers the force of the wire to the handle to prevent buckling of the bendable tube when the distal segment deflects.

Catheters are used for a large number of surgical procedures. For example, in many relatively new surgical techniques, e.g., endoscopic surgery, a small opening is made in the patient, and one or more catheters or cannulas are inserted into the opening to provide various working passageways through which small surgical instruments can be advanced into the patient to perform the particular procedure. To keep the opening as small as possible, it is desirable to minimize the diameter of the catheters.
Not surprisingly, it is sometimes advantageous that as the catheter is being positioned in the patient, the catheter be able to bend at predetermined locations, either to aid in advancing the catheter along a tortuous path or to avoid an obstructing object inside the patient. Simply pre-bending a catheter at a predetermined location on the catheter, however, can interfere with inserting the catheter along a straight-line path, and is therefore oftentimes undesirable.
Accordingly, past attempts have been made to make an entire catheter out of a flexible material. These devices sometimes provide a means for bending the catheter. One example of such a means is a manipulable wire connected to the catheter at the location where the bend is to occur. The catheter can be bent at the point of wire connection by pulling the wire.
Unfortunately, such devices are subject to buckling and do not always bend in proportion to the pulling force of the wire, making it difficult to reliably gauge the amount of pulling force necessary to bend the catheter an appropriate amount. Also, such catheters often lack structural strength to the extent that they can undesirably bend at unintended locations.
To overcome the structural strength problems mentioned above, catheters may be made of thin-walled strong and rigid material, such as steel. These catheters, however, cannot easily conform to the contours of a body vessel or duct. It is desirable for a catheter to conform to follow a body vessel or duct.
Accordingly, it is an object of the present invention to provide a catheter which can be bent at one or more predetermined location on the catheter. Another object of the present invention is to provide a small diameter, thin-walled bendable catheter that has a relatively high degree of structural strength. Further, it is an object of the present invention to provide a catheter which is easy to use and cost-effective to manufacture.

Flexible endoscope with hypotube activating wire support


A non-volatile semiconductor memory device includes a semiconductor substrate, an insulating film formed on the semiconductor substrate, a plurality of memory cells formed on the semiconductor substrate, a plurality of first assist gates extending toward the memory cell, a connection portion connecting end portions of the first assist gates, a second assist gate extending toward the memory cell, a first select transistor controlling whether to apply a voltage to an area under the first assist gate, a second select transistor controlling whether to apply a voltage to an area under the second assist gate, and an impurity region. The insulating film formed under an intersection area of the connection portion and the impurity region has a thickness larger than the insulating film formed under the first and second assist gates. A non-volatile semiconductor memory device capable of ensuring a writing speed as well as reliability can thus be obtained.

1. Field of the Invention
The present invention relates to a non-volatile semiconductor memory device, and more particularly to a non-volatile semiconductor memory device including an assist gate.
2. Description of the Background Art
Various attempts have conventionally been made in order to reduce a size of a non-volatile semiconductor memory device (see Japanese Patent Laying-Open No. 2000-188346). An AG-AND type flash memory has been proposed as a technique to make smaller a non-volatile semiconductor memory device. In the AG-AND type flash memory, a bit line of a memory cell transistor is implemented not by a diffusion layer but by an inversion layer formed on a main surface of a semiconductor substrate when a voltage is applied to an assist gate. Accordingly, as it is not necessary to form an impurity region for forming a bit line in a memory cell area, the non-volatile semiconductor memory device can be reduced in size. Such a technique is described, for example, in Y. Sasago, et. al., "90-nm-node multi-level AG-AND type flash memory with cell size of true 2 F2/bit and programming throughput of 10 MB/s," IEDM Tech. Dig., (2003) p. 823.
The AG-AND type flash memory has a semiconductor substrate and an insulating film formed on the semiconductor substrate, and includes a memory cell area and a peripheral circuit area adjacent to the memory cell area. The memory cell area includes a floating gate and a control gate arranged on an upper surface of the floating gate, and a plurality of memory cells are formed in the memory cell area.
The peripheral circuit area includes a plurality of assist gates formed on the insulating film and an electrode portion applying a voltage to a lower surface of the assist gate.
In the conventional AG-AND type flash memory structured as above, at the time of writing, a voltage is applied to one assist gate to form an inversion layer under the assist gate, to which a voltage is applied. Then, a voltage is applied to the other assist gate to form an inversion layer under this assist gate, to which a voltage is applied. Accordingly, a write current is generated under the floating gate, so that data is written in the floating gate arranged between two assist gates. A reading operation and an erasing operation are performed also by applying voltages of various magnitudes to the assist gates.
During the reading operation or the like, voltages applied to respective assist gates and the inversion layer are different in magnitude. Therefore, depending on each operation and position, magnitude of the voltage applied to the insulating film formed under the assist gate or the like is considerably different. Meanwhile, the insulating film formed on the semiconductor substrate has a uniform thickness.
An example of a non-volatile semiconductor memory device having a gate insulating film different in thickness from a position to a position formed on a semiconductor substrate is described in Japanese Patent Laying-Open No. 2001-044395. The non-volatile semiconductor memory device includes a semiconductor substrate, a gate insulating film formed on the semiconductor substrate, a memory cell transistor formed on the gate insulating film within the memory cell, and a select transistor. The gate insulating film of the select transistor has a thickness larger than that of a tunneling insulating film of the memory cell transistor. According to this non-volatile semiconductor memory device, an operation speed of the select transistor can be improved.
In addition, an example of a non-volatile semiconductor memory device having a gate insulating film different in thickness from a position to a position formed on a semiconductor substrate is described in Japanese Patent Laying-Open No. 2000-269361.
The non-volatile semiconductor memory device has a memory cell including a memory cell transistor and a select transistor. The memory cell transistor and the select transistor are different from each other in a film thickness and a threshold voltage.
In the conventional AG-AND type flash memory, a high voltage is applied to a part of the insulating film during various operations, with the result that reliability has not been ensured. In particular during the writing operation, as a voltage larger than in other type of operation is applied to each assist gate, a large voltage is applied to a part of the insulating film formed under the assist gate, which results in difficulty in achieving ensured reliability.
If a thickness of the insulating film is set using a position to which a high voltage is applied as a reference, a writing speed is disadvantageously lowered.
In addition, none of the inventions according to Japanese Patent Laying-Open Nos. 2001-044395 and 2000-269361 is directed to ensuring reliability of the insulating film, nor related to an AG-AND type flash memory.

Non-volatile semiconductor memory device


A sealed-shaft gravity-buoyancy energy system and method of use thereof, wherein a wheel is powered by ball masses which fall under gravitational force, thereby causing the wheel to rotate. The ball masses are collected and inserted into a fluid shaft, wherein the fluid shaft comprises at least two separate columns having valves at the ends thereof to provide a sealing function, thereby preventing fluid loss. Buoyant force raises the ball masses to the top of the device, wherein the ball masses are deposited once again onto the wheel. A generator or other device utilizes the rotational force of the wheel to create energy.

As concerns about our nation's dependence on foreign oil increase, and as Americans become more aware of the environmental impacts of foreign petroleum use in the environment and the economy of the country, interest in alternative energy sources, such as, domestically produced alternative fuels, and wind, solar, and geothermal production energy is increasing for fueling of the transportation engines as well as generation of electrical energy.
Natural force energy, such as wave energy and energy produced from gravitational and buoyant forces are also finding interest. Various devices and methods have been developed that utilize natural forces to provide power. For instance, U.S. Pat. No. 5,753,978 to Chih-Chiang teaches powering of two sets of fluid pumps to pump fluid to the top of fluid tanks, two sets of conveyors to transfer floaters (balls), two sets of hydraulic cylinders to insert balls into the two fluid tanks, and the operation of a set of two double-wall airtight gates. The principal difficulty with pumping devices, such as that of Chih-Chiang '978, is the need to raise the fluid head, thereby requiring a large expenditure of energy and further causing a pause in the operation; that is, an undesired idle time.
U.S. Pat. No. 3,857,242 to Gilmore discloses cylinders and chains connected weights. Gilmore '242 exhibits the difficulties of maintaining a seal between the air and fluid media, and does not teach a means for hermetically sealing the buoyancy shaft, while allowing the transportation of the weights up the shaft.
Other devices utilize buoyant objects in concert with wave motion to produce energy via piezoelectric means, such as is taught by U.S. Pat. No. 5,578,889 to Epstein. However, such devices are limited to use where waves are generated or otherwise available.
Therefore, it is readily apparent that there is a need for an energy generating system and method of use thereof, wherein the system effectively and efficiently utilizes buoyant and gravitational forces, thereby overcoming the aforementioned disadvantages of having to raise fluids to a substantial head height, sealing difficulties, and/or requiring a source of wave motion.

Sealed shaft gravity buoyancy energy system and method of use thereof


The movement of skin on an animated target, such as a character or other object, is simulated via a simulation software application. The software application creates a finite element model (FEM) comprising a plurality of finite elements based on an animated target. The software application attaches a first constraint force to a node associated with a first finite element in the plurality of finite elements. The software application attaches a second constraint force to the node. The software application detects a movement of the first finite element that results in a corresponding movement of the node. The software application determines a new position for the node based on the movement of at least one of the first finite element, the first constraint force, and the second constraint force.

1. Field of the Invention
The present invention relates to the field of computer animation and, in particular, to skin and flesh simulation using finite elements, biphasic materials, and rest state retargeting.
2. Description of the Related Art
Computer-based animations often involve modeling the behavior of flesh and skin on characters and other objects such that skin and flesh move in a believable and visually pleasing manner when the characters are animated. The movement of skin and flesh is simulated by using a physics-based simulation software application. Such a software application determines the position of a character's skin and flesh based on the movement of the character and the model used for the flesh and skin. One approach for modeling flesh involves a material with a specific stiffness, such that flesh stretches as the underlying character moves and deforms. The animator selects a proper stiffness that causes the character's flesh to move in a plausible manner as the character undergoes various basic movements, such as walking, crawling, or running.
One drawback of this approach is that, while such a model may provide plausible flesh movement when the character undergoes movement involving small deformations, the model behaves poorly when the character undergoes larger deformation. For example, a stiffness value could be selected to creates plausible flesh movement for low deformation actions such as walking. The same stiffness value may cause the character's flesh to separate, or rip away, from the character if the character undergoes a rapid change in motion, such as jumping off a bridge. As a result, animators may need to manually adjust each shot to achieve plausible flesh motion, particularly when a character undergoes a sudden change in momentum. For example, an animator could add an inertial field generator associated with the character, so causing the simulator to believe the character is not actually jumping off a bridge. Such manual per-shot approaches are time consuming for the animator, and thus increase production costs and production cycles.
Skin motion may be simulated by using a mass-spring system. With such an approach, discrete nodes in space are each assigned a mass. The nodes are interconnected via springs, where the springs are models for forces that allow the skin to deform and then to restore to an original position as the underlying character animates. The interconnected nodes form a mesh that surrounds the character. One set of springs attempts to maintain the relative positions of the masses by maintaining the length of the edges connecting the masses. Potentially a second set of springs attempts to maintain the areas of the triangles formed by the mesh that interconnects the nodes. Typically, such mass-spring models exhibit linear stretching behavior. One drawback of this approach is that each spring in mass-spring systems typically attempts to maintain the spring's initial, or reference, length, resulting in an incorrect visual appearance of the skin or flesh as the animated character experiences sudden or exaggerated motion. Another drawback of this approach is that such mass-spring models can cause the skin to stretch unrealistically across portions of the character while compressing and folding over in others portions of the character. As a result, such mass-spring models typically involve multiple simulation parameter sets for different classes of motion, resulting in increased simulation setup time for each different shot.

Skin and flesh simulation using finite elements, biphasic materials, and rest state retargeting


The present invention relates to a novel polyimide of the general formula (1)

This invention relates to novel polyimides and a process for the preparation thereof More particularly the invention relates to polymides having formula (1)
and a process for their preparation using a renewable resource, Cashew Nut Shell Liquid (CNSL). The polyimides provided by the present invention are useful particularly as alignment films for liquid crystal display devices. The polyimide of formula (1) may be a homo or copolyimide comprising an aromatic diamine having at least one pentadecyl phenoxy group per benzene ring as shown in formula (2)
as the essential diamine component and a tetracarboxylic acid or its derivative (R1) and optionally other common diamines. R2 will be the compound having formula (2) in the case of homopolyimides and will be a common diamine in the case of copolyimides.
Polyimides are widely used as protective materials or insulating materials in electric and electronic fields due to their high mechanical strength, heat resistance and solvent resistance. However, developments in electric and electronic fields have been remarkable in recent years, and increasingly high levels of properties have been required for the materials to be used in such fields. Especially for alignment films for liquid crystal display devices, polyimides have heretofore been employed in most cases by virtue of the uniform quality and durability of the coated film surface. However along with the trend for high densification and high performance of display devices, the surface properties of the polyimide coating films have become particularly important, and it has been necessary to impart new properties which conventional polyimides do not have.
Liquid crystal display devices are display devices, which utilize electrooptical changes of liquid crystals, and they are small in size and light in weight and have a feature that their power consumption is small. Accordingly they have found remarkable developments in recent years as display devices for various displays. In certain liquid crystals cells, particularly in those with nematic and cholestric liquid crystals, the cell wall which are in contact with the liquid crystal material must be provided with alignment layers to achieve the desired molecular orientation of the liquid crystals. As a rule, the alignment layers are deposited so that molecules at opposite cell walls lie mutually at 90xc2x0 C. The alignment layer consists either of inorganic substances deposited by oblique evaporation in a vacuum or of organic substances applied by dipping, brushing, or spraying.
Alignment layers of inorganic materials, such as calcium fluoride or silicon monoxide, are formed by evaporating the substances in a high vacuum at a very small angle to the substrate. Such layers are not suitable for mass production because they require a large amount of work and apparatus.
Alignment layers of organic materials are relatively easy to produce because the organic material, dissolved in a solvent can be applied by dipping, spraying, or brushing. In such layers, the desired molecular orientation is achieved by subjecting the applied material to directional mechanical action, particularly by rubbing the surface in a predetermined direction with a cloth of e.g. nylon, rayon, or polyester. The liquid crystal molecules then align themselves on such a layer by adhering at one end to the organic material. The organic film used may be polyvinyl alcohol, polyoxyethylene, polyamide, or polyimide. However polyimide is commonly used in view of the chemical stability, thermal stability, etc. however, the tilt angle obtainable by rubbing the polyimide is usually at a level from 1xc2x0 to 3xc2x0 and it has been difficult to attain a large tilt angle.
In the field of liquid crystal alignment films, it has been difficult to obtain a large tilt angle constantly by rubbing an organic film of polyimide or the like. As a means to solve this problem, Japanese Unexamined Patent Publication No. 297819/1987 discloses a treating agent for liquid crystal alignment comprising of a reaction product of a long chain alkylamine with a polyimide precursor. Further, Japanese Unexamined Patent Publication No. 262527/1989 and No. 262528/1989 disclose an agent for liquid crystal alignment which comprises of a mixture comprising a long chain alkyl compound and a polyimide precursor. Japanese Unexamined Patent Publication No. 25126/1989 discloses a treating agent for liquid crystal alignment which comprises of a polyimide prepared from a diamine having an alkyl group. Thus many attempts have been made to increase the pretilt angle of the liquid crystal by introducing an alkyl group into a polyimide, and it has been possible to increase the tilt angle to some extent. On the other hand, such attempts have resulted in a new problem when an alkyl group is introduced into a polyimide to increase the tilt angle, the wettability of liquid crystal tends to be low, and in an extreme case, the failure in liquid crystal alignment is likely to result. Consequently, the display performance of the liquid crystal display device tends to be poor.
It is therefore necessary to develop a polyimide alignment film, which gives good tilt angle as well as adequate wettability. U.S. Pat. No. 5861534/1999 discloses a polyimide alignment layer prepared from different diamines with long alkyl group and a readily polarizable chemical bond group, which gives good alignment properties.
The main object of the present invention is therefore to provide novel polyimides and a process for the preparation thereof.
Another object is to provide a process for the preparation of the polyimides, which can be used to synthesize a polyimide liquid crystal alignment layer from a renewable and economically viable resource, cashew nut shell liquid.
It is observed that reacting a diamine containing at least one mole % of the diaminobenzene derivative of formula (2), which contains a pentadecyl phenoxy group, introduced to the diamine structure from a naturally occurring renewable resource, cashew nut shell liquid and a tetracarboxylic acid or its derivatives (R1), optionally with other common diamines provides a homo or copolyimide having formula (1). R2 is compound having formula (2) in the case of homopolyimides and common diamines in the case of copolyimides. The use of such a diamine, which was synthesized from a naturally occurring renewable and economically viable resource, the cashew nut shell liquid, opens a new route for the production of polyimide having on its side chain, a substituent similar to a liquid crystal molecule and with excellent aligning properties and high solubility in common organic solvents.
Accordingly, the present invention provides a polyimide of the general formula (1)
wherein R1 is a tetracarboxylic acid or a derivative thereof and R2 is a compound of formula 2 or a diamine
In one embodiment of the invention, the polyimide of formula 1 is a homo or a copolyimide.
The present invention also provides a process for the preparation of a polyimide of the general formula (1) said process comprising reacting a diamine including an aromatic diamine having at least one pentadecyl phenoxy group per benzene ring of formula (2)
as the essential diamine component with tetracarboxylic acid or a derivative thereof optionally in the presence of a second diamine in a solvent at a temperature ranging between 120xc2x0 C. to 220xc2x0 C. in a stream of inert gas for a period ranging between 6 to 12 hrs, precipitating the resulting polymer in methanol, filtering and drying to obtain the desired polyimide of formula 1.
In yet another embodiment of the invention the solvent used for polymerization is a high temperature solvent selected from nitrobenzene, benzonitrile, xcex1-chloronaphthalene, o-dichlorobenzene, trichlorobenzenes, and phenolic solvents such as m-Cresol, o-Cresol, p-Cresol, o-Cresol, o-Chlorophenol and p-Chlorophenol.
In a further embodiment of the invention, the solvent used for the polymerisation is m-Cresol.
The present invention also relates to a process for the preparation of a polyimide of formula (1) said process comprising reacting a diamine having formula (2)
with a tetracarboxylic acid or a derivative thereof, optionally with a second diamine in a dipolar aprotic amide or sulphoxide solvent at a temperature ranging between 0xc2x0 C. to 15xc2x0 C. under a stream of inert gas for a period ranging between 5 to 24 hrs. to obtain a polyimide precursor, imidizing the said polyimide precursor to obtain the desired polyimide.
In one embodiment of the invention, the polyimide precursor is chemically imidized by adding dehydrating agents like acid anhydrides in the presence of tertiary amines and heating at a temperature between 30xc2x0 C. to 120xc2x0 C. for 2 to 24 hrs, precipitating the resulting polymer in methanol, filtering and drying to obtain the said polyimide.
In one embodiment of the invention, the polyimide precursor is thermally imidized in the form of a film by coating on a glass substrate and subsequently heating from 100xc2x0 C. to 400xc2x0 C.
In another embodiment of the invention, the tetracarboxylic acid and its derivative is selected from pyromellitic acid, 2,3,6,7-naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, 1,2,5,6-naphthalene tetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3xe2x80x2,4,4xe2x80x2-biphenyl tetracarboxylic acid, 2,3,3xe2x80x2,4xe2x80x2-biphenyl tetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3xe2x80x2,4,4xe2x80x2-benzophenone tetracarboxylic acid, bis(3,4-dicarboxyphenyl)sulphone, bis(3,4-dicarboxyphenyl)methane, 2,2-bis (3,4-dicarboxyphenyl)propane, bis (3,4-dicarboxyphenyl)dimethyl silane, 1,1,1,3,3,3-hexafluro-2,2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)diphenyl silane, 2,3,4,5-pyridine tetracarboxylic acid and 2,6-bis(3,4-dicarboxyphenyl)pyridine, and their dianhydrides, alicyclic tetracarboxylic acids such as 1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cyclopentane tetracarboxylic acid, 1,2,4,5-cyclohexane tetracarboxylic acid, 2,3,5-tricarboxycyclopentylacetic acid and 3,4-dicarboxy -1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, and their dianhydrides.
In another embodiment of the invention the second diamine is selected from the group consisting of p-phenylenediamine, m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 4,4xe2x80x2-diaminobiphenyl, 3,3xe2x80x2-dimethyl-4,4xe2x80x2-diaminobiphenyl, 3,3xe2x80x2-dimethoxy -4,4xe2x80x2-diaminobiphenyl, diaminodiphenyl methane, diaminodiphenyl ether, 2,2xe2x80x2-diaminodiphenyl propane, bis(3,5-diethyl-4-aminophenyl)methane, diaminodiphenyl sulphone, diaminobenzophenone, diaminonaphthalene, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl)anthrazene, 1,3-bis(4-aminiophenoxy)benzene, 4,4xe2x80x2-bis(4-aminiophenoxy)diphenyl sulphone, 2,2xe2x80x2-bis[4-(4-aminiophenoxy) phenyl]propane, 2,2xe2x80x2 bis(4-aminiophenyl)hexafluropropane and 2,2-bis[4-(4-aminiophenoxy) phenyl]hexafluro propane.
In another embodiment of the invention, the dipolar aprotic solvent used is selected from the group consisting of amide solvents such as N-methylpyrrolidinone, N,N-dimethylacetamide, N,N-dimethyl formamide and tetramethylurea and sulphoxides such as dimethylsulphoxide.
In yet another embodiment of the invention, the dehydrating agent used for chemical imidization is selected from the group consisting of acetic anhydride, propionic anhydride, n-butyric anhydride and benzoic anhydride.
In still another embodiment of the invention, the tertiary amine used for chemical imidization is selected from the group consisting of pyridine, methylpyridines, lutidine, N-methylmorpholine and trialkylamines.
In another embodiment of the invention, the diamine of formula 2 is used singly or two or more in combination.
In a further embodiment of the invention, the tetracarboxylic acid or derivative thereof is used singly or as two or more of in combination.
In a further embodiment of the invention, the ratio of the molar amount of the said tetracarboxylic dianhydride or combination of tetracarboxylic dianhydrides to the molar amount of the said diamine or combination of diamines of formula 2 is between 0.8 to 1.2.
In another embodiment of the invention, the molar amount of tetracarboxylic dianhydride or total molar amount of two or more tetracarboxylic dianhydrides is equal or almost equal to the molar amount of single diamine or total amount of two or more diamines of formula 2.
In another embodiment of the invention, the concentration of the polymer solution is 5 to 40% by weight.
In a further embodiment of the invention, the concentration of the polymer solution is 10 to 25% by weight.
The present invention also relates to a polyimide alignment layer for liquid crystal display devices comprising the polyimide of formula 1.
The present invention also relates to a process for the preparation of a polyimide alignment layer for liquid crystal devices said process comprising spin coating the polyimide of formula 1 dissolved in a suitable common organic solvent on a glass substrate.
In another embodiment of the invention, the polyimide alignment layer for liquid crystal devices is obtained by spin coating the polyimide precursor solution of the polyimide of formula 1 on a glass substrate and heating to form the polyimide film and then subjecting it to rubbing treatment using a polar cloth.
The synthesis of novel polyimides and their application as liquid crystal alignment layers are described herein below with reference to examples, which are illustrative and should not be construed as limiting the scope of the present invention in any manner.

Polyimides, process for the preparation thereof and use thereof as alignment films for liquid crystal devices

Council of Scientific and Industrial Research

Laboratoire des Materiaux Organiques a Proprietes Speciques


A compact high power laser dazzling device includes at least one heat sink, multiple laser resonators and an optical head. Each of the laser resonators extends axially from a first end, fixedly mounted to the heat sink, to a second end emitting an individual laser beam. The optical head is disposed adjacent to the second ends of the laser resonators and includes an optical transmission assembly that directs the individual laser beams of the laser resonators to define a region of overlap at a remote point a predetermined distance from the optical head. A laser beam intensity adjuster assembly may be disposed adjacent the output end of the optical head. The laser beam intensity adjuster assembly includes a front face having multiple apertures. At least one of the apertures has a holographic diffuser element mounted therein and at least one of the apertures has an optically clear window element or no optical elements mounted therein.

This disclosure relates generally to the field of portable illumination devices for illuminating an ambient environment. More particularly, the present disclosure relates to a hand-held laser device that could be used as an effective non-lethal security means, whereby temporary visual impairment reduces a subject's ability to engage in disruptive and/or violent actions.
Methods and devices for producing glare or flashblind effects from a portable visual security device have been disclosed for example, in U.S. Pat. No. 5,685,636 to German, in U.S. Pat. No. 6,190,022 to Tocci et al and in U.S. Pat. No. 6,799,868 to Brown et al. among others. These prior art devices operate by producing radiation at intensities sufficient to dazzle a subject by temporarily reducing visual performance while remaining below levels that can result in permanent damage to the subject's retina.
Generally, to ensure that the device is eye safe, it is an accepted practice that the intensity at the location of the target not exceed, one half the maximum permitted exposure (MPE) value for a particular wavelength. In some cases, the device is expected to meet the requirements of ANSI standard, which allows only 10% of the MPE for a given exposure duration. To comply with this requirement, the devices of the prior art were generally limited to intercepting static targets located at or beyond a certain range, or else they allowed adjustments of the power and/or the beam spread of the output radiation to thereby alter the intensity at the estimated target's location in real time.
Means for changing the beam's spread generally involved controlling the spot size using an adjustable lens contained in the device, as was taught, for example, in U.S. Pat. No. 5,685,636. Alternatively, a fixed beam expanding lens could be disposed in the path of the beam, with the power of the output adjustable up to a maximum specified by eye safety considerations. This realization has the advantage of being adaptable to intercepting moving targets in a variety of scenarios and for a range of exposure times, and could be readily packaged in a compact flashlight type device. It had the further advantage of affording a degree of operational and practical flexibility through utilization of Gaussian beam profiles such as are typically produced by most solid state laser sources, including diodes and diode pumped lasers.
Although effective in certain situations, the laser flashlights and visual security devices of the prior art, including the ones taught in the patents cited above, are deficient in that they could not always provide sufficient power to allow use in certain circumstances. Examples of scenarios requiring greater power than available from existing and prior devices may include operation at higher duty cycles, over longer ranges and/or under adverse ambient light conditions such as clear sunny daylight or in rain or foggy conditions. Even the compact laser flashlight device taught in U.S. Pat. No. 6,799,868 is generally limited to less than about 250 mW at the operational wavelength of 532 nm, due to practical considerations of cost and performance. Power levels available at various other visible wavelengths from diode lasers are typically much lower, especially when TEM 00 outputs are required as well.
Generally, power scaling from a single laser emitter, whether a semiconductor laser or a diode pumped solid state laser (DPSSL) is limited by trade-offs between power consumption properties, resonator design limitations (including thermal lensing), sizing of optical components and the amount of battery power available in a portable unit which can restrict the amount of "on" time and/or duty cycle. Furthermore, the cost of the components tend increase substantially as the power is scaled, putting the device beyond reach for certain security applications. It is therefore desirable to provide a cost effective security device with scalable output power outputs of 1 W and beyond in the visible, while maintaining portability features and effectiveness.

Compact high power laser dazzling device


A method of the invention for inspecting a defect on a translucid film is provided. The method includes an anti-reflective coating (ARC) layer over the translucid film. The anti-reflective coating (ARC) layer prevents inspecting light from penetrating through the ARC layer and reduces the amount of inspecting light refracting through the translucid film. The inspection is performed by generating an inspecting light with a predetermined angle radiating on the ARC layer. The reflecting light message from different regions of the anti-reflective coating (ARC) layer are separately collected. The reflecting light messages are compared die to die to calculate an inspecting result.

1. Field of the Invention
The invention relates in general to the method of inspecting a defect on a translucid film, and more particularly to the method of inspecting a defect on a translucid film by adding an anti-reflective coating (ARC) on the translucid film.
2. Description of the Related Art
In the semiconductor process, after forming an translucid layer, for example, an oxide layer, on a semiconductor substrate by deposition, there is usually a following polishing step to flatten the surface of the translucid layer. The preferred polishing is chemical mechanical polishing (CMP). After polishing, the engineers inspect the quality of the insulating layer by several methods. Currently, the preferred inspecting method includes Tenco particle inspection using the American Tenco AIT-type machine. Generally speaking, the insulating layer can be considered a translucid layer. When an incident light radiates on the surface of the insulating layer, it usually generates both refraction and reflection. The reflective light reflects back from the surface of the insulating layer and the refractive light penetrates the insulating layer. Therefore, engineers usually term the insulating layer the translucid layer.
A conventional method to inspect a defect on a translucid film is Tenco particle inspection. First, an incident light is provided, for example, laser light with a predetermined angle. The incident light radiates on the surface of the translucid layer to inspect a defect particle on the translucid layer. The predetermined angle is determined to make total reflection on the translucid layer. The reflective light reflects from the translucid layer and is collected by Tenco inspectors. The reflective lights reflecting from different regions of the translucid layer, for example, different dies, have different light messages.
FIG. 1 showing a conventional method of inspecting a defect on a translucid film. First, a semiconductor substrate 10 is provided. A translucid layer 11, for example, an oxide layer, is formed on the semiconductor substrate 10 by deposition. Polishing the translucid layer 11 is performed to flatten the surface of the translucid layer 11 using chemical mechanical polishing (CMP). After polishing, defect particles 12 are formed and dishes 14 are formed because of dishing effects. Then an inspecting step is performed. A laser light with a predetermined angle radiates on the translucid layer 11. There are reflections from different regions of the translucid layer 11. As shown in FIG. 1, light 13A totally reflects from the translucid layer 11 and light 13B which radiates on sidewall of the dish 14 partially reflects and partially refracts. Partial light 13B refracts through the translucid layer 11 and partial light 13B reflects from the surface of the translucid layer 11. Light 13C scatters because of the defect particle 12.
At the beginning, the incident light with the predetermined angle satisfies total reflection conditions. The predetermined angle is determined satisfying the total reflection angle. When the incident light radiates on the dish 14 which is formed because of dishing effect, the predetermined angle on the dish 14 is no longer the total reflection angle. Therefore, the incident light radiating on the dish 14 partially reflects and partially refracts. If the incident light partially refracts through the translucid layer 11, the partially refracting light then reflects on the semiconductor substrate 10. The reflecting light from the semiconductor substrate 10 disturbs the original incident light to generate variable light intensity. The variable light intensity (color variation) affects inspection, reducing the accuracy of inspection results.

Method of inspecting a defect on a translucid film


The present disclosure provides a pixel circuit, a method for driving a pixel circuit, a display panel, and a display apparatus. The pixel circuit includes a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, a capacitor, and a light-emitting diode. In the above pixel circuit, the first light emitting control signal and the second light emitting control signal are provided to respectively initialize the first polar plate and the second polar plate of the capacitor, to ensure the same initial state of the pixel circuits.

Organic light-emitting display panels are more and more widely used in the field of display technology due to their benefits of high contrast, low power consumption, wide viewing angle, fast response speed. An organic light-emitting display panel is usually provided with pixel circuits arranged in an array. The pixel circuit usually includes a plurality of light-emitting diodes and a power supply.

Pixel circuit, method for driving pixel circuit, display panel, and display apparatus

KUNSHAN GO-VISIONOX OPTO-ELECTRONICS CO., LTD.


A scrambling and a descrambling circuit for cordless telephone provides a higher security level than current phone scrambling circuitry. The higher security level is accomplished by separating an audio signal into low and high frequency bands. The frequency bands are selectively inverted or non-inverted during scrambling and descrambling according to common selection conditions. The processed signals are mixed into an overall mixed signal. The overall mixed signal is selectively inverted or non-inverted during scrambling and descrambling according to a common selection condition to increase the phone's transmission security level.

(1) Field of the Invention
The present invention relates to cordless telephone systems and, more particularly, to a scrambling and a descrambling circuit for a cordless telephone.
(2) Description of the Related Art
Cordless telephones are widely used because of the convenience. In many cordless telephone systems, the transmission signals between the cordless telephone handset and the base station that carry private conversations can be casually received and eavesdropped.
Scrambling technology is used to prevent eavesdropping of the private phone conversations developed in voice and non-voice communication systems.
Scrambling techniques used in voice communication systems are classified under four categories. These four scrambling categories are frequency domain scrambling, time domain scrambling, amplitude scrambling and two-dimensional scrambling. Details of these four scrambling skills are disclosed in the paper entitled "A Comparison of four Methods for Analog Speech Privacy"(IEEE Transactions on Communications. Vol. COM-29, NO. 1, January 1981.) by Jayant et al.
Among the four scrambling categories, frequency domain scrambling is classified as using the methods of frequency inversion, band-shift inversion and spread spectrum. The spread spectrum method changes the band width of a scrambled signal. The frequency inversion and band-shift inversion methods do not change the band width of a scrambled signal.
In cordless telephone systems, the band width of an audio signal is generally restricted to a frequency of 300 Hz to 3400 Hz. Because the spread spectrum method changes the band width of the scrambled signal, it cannot be used for scrambling the restricted frequency band in cordless telephone systems.
Referring to the attached drawings, prior scrambling skills according to the frequency inversion and band-shift inversion methods will be described below.
The circuit in FIG. 4 is a frequency inversion scrambling circuit implemented in a transmitter such as located in a cordless telephone base unit. The circuit in FIG. 4 can also be used in descrambling circuits of a receiver such as located in a cordless telephone hand set. The frequency inversion scrambling circuit includes a first low pass filter 41 for receiving an audio input signal IN, a modulator 43 for receiving a predetermined split frequency Fs and the output signal of the first low pass filter 41. A second low pass filter 42 receives the output signal of the modulator 43 and generates an output signal OUT.
The first low pass filter 41 passes through the input signal IN for a frequency band lower than a given cutoff frequency. The modulator 43 outputs two frequency components, which are inverted and non-inverted signals of the output signal from the low pass filter 41. The modulator 43 transposes an inverted frequency component and a non-inverted frequency component symmetrically on the left and right side of the split frequency, respectively. The second low pass filter 42 passes through the output signal, from the modulator 43, having a frequency band lower than a given cutoff frequency, and provides the filtered signal that serves as an output signal OUT.
FIGS. 5A-5C and FIGS. 6A-6C illustrate the scrambling and descrambling waveforms respectively in the case that the cutoff frequency of the first and second low pass filter 41 and 42 is 3.4 KHz and the split frequency Fs of the modulator 43 is 3.7 KHz.
FIG. 5A shows a filtered output signal, from the first low pass filter 41 for an audio signal having a frequency band lower than 3.4 KHz. FIG. 5B shows the output signal of the modulator 43. The filtered output signal from the low pass filter 41 is inverted and the inverted signal is symmetrical on the left and right side of the split frequency Fs at 3.7 KHz. FIG. 5C shows the output signal OUT of the second low pass filter 42. The output signal OUT has a frequency band lower than the 3.4 KHz and is obtained low pass filter 42 of filtering the output signal of the modulator 43.
From the comparison of FIGS. 5A and 5C, the scrambling circuit inverts the low and high frequency components of the input signal IN, such that the low and high frequency components of the input signal IN are transformed into the high and low frequency components, respectively, of the output signal OUT.
The scrambled audio signal, from the scrambling circuit, is transmitted to a receiver by a communication channel. The transmitted signal is descrambled by the descrambling circuit in the receiver to obtain the original audio signal.
FIGS. 6A-6C show the descrambling procedure, when the circuit in FIG. 4 is used as a descrambling circuit in the receiver. The scrambling and descrambling circuitry are essentially the same in configuration. For convenience of description, we also consider the circuit in FIG. 4 as a descrambling circuit.
FIG. 6A shows the output signal of a first low pass filter 41. The first low pass filter 41 accepts a transmitted audio signal and passes through the transmitted audio signal having a frequency band lower than a given cutoff frequency. FIG. 6B shows the output signal of the modulator 43. The modulator 43 outputs two frequency components, which are an inverted and non-inverted signals of the output signal from the low pass filter 41. The modulator 43 transposes an inverted frequency component and a non-inverted frequency component symmetrically on the left and right side of the split frequency, respectively.
FIG. 6C shows the output signal of the second low pass filter 42. The second low pass filter 42 accepts the output signal of the modulator 43 and passes through the signal having a frequency band lower than a given cutoff frequency. The second low pass signal provides the filtered signal that serves as an output signal OUT. The cutoff frequencies of the two low pass filters and the split frequency of the modulator in the receiver are the same as those in the transmitter. As shown in FIGS. 5A and 6C, the input signal IN of the scrambling circuit in the transmitter is the same as the output signal OUT of the second low pass filter in the receiver.
FIG. 7A is a waveform showing the input signal of the modulator 43, and FIG. 7B is a waveform showing the output signal of the modulator 43.
The scrambling and descrambling circuits shown in FIG. 4 are widely used since the configuration is very simple. However, the scrambled signal output by the circuit described above is easily descrambled with a simple RF (radio frequency) receiver. Thus, eavesdropping of conversations from the cordless telephone can be easily conducted by tuning into the split frequency of the telephone modulator. Moreover, even when the exact split frequency is unknown, eavesdropping can still be performed as long as the RF receiver is tuned within the vicinity of the split frequency. For example, when the split frequency is 3.7 KHz, setting the modulator of the RF receiver to a split frequency of 3.5 KHz, still allows eavesdropping of the conversation.
FIGS. 8A and 8B show a scrambling procedure according to the band-shift inversion method. FIG. 8A is a graph showing power density of an audio signal as a function of frequency before scrambling. FIG. 8B is a graph showing power density of the audio signal as a function of frequency after scrambling. As shown in FIGS. 8A and 8B, an audio signal is separated into two parts, a low frequency band and a high frequency band, by a band split frequency Fs. The form of FIG. 8B is an inverted form of FIG. 8A.
The scrambling circuit according to the prior band-shift inversion method can obtain a relatively high security level. However, the configuration of the scrambling circuit is quite complicated. However, the scrambling circuit according to the band-shift inversion method also still allows room for a conversation to be eavesdropped by someone, because it is easy to determine the band split frequency Fs.

Scrambling and descrambling circuit for a cordless telephone


Systems and methods allowing an instant messaging user to exchange messages with an e-mail user. To the instant messaging user, the experience is a seamless exchange of instant messages; to the e-mail user, the experience is a seamless exchange of e-mail messages. Conversion of an instant message to an e-mail message includes insertion of a token into the e-mail message, and conversion of an e-mail message to an instant message includes validating a token extracted from the e-mail message.

The present invention related to communication via a network such as the Internet, and in particular to systems and methods for exchanging messages between an instant messaging user and an e-mail user.
The Internet offers various ways for users to communicate with other users, including electronic mail (e-mail) and instant messaging. These two communications media differ in various respects. For instance, e-mail is an open system: an e-mail user with access to the Internet can exchange e-mail messages with anyone else who has access to the Internet, regardless of which service providers the sender and recipient use.
While the openness of e-mail provides great flexibility, it also allows various abuses. For instance, most e-mail servers assume that users want to receive all incoming mail. While some systems allow a user to define various filters to block selected senders, there is generally no mechanism enabling a user to reliably limit who can send messages to that user. As a result, unwanted e-mail messages (commonly referred to as "spam") from senders with whom a user has no prior association have become a significant problem. In addition, while e-mail servers typically require a user to log in to access his or her e-mail account, e-mail protocols generally do not include a mechanism for establishing security or trust between a sender's system and a recipient's system. Since e-mail headers can be forged, it can be difficult for a recipient of a message to be certain that a message purporting to be from a particular sender is really from that sender.
Partly as a consequence of these drawbacks, instant messaging (IM) has become increasingly popular. Instant messaging provides communication within a closed community, i.e., only registered users can send or receive messages via an instant messaging service. Because users are required to sign in to the same system (if not necessarily the same server) with a preselected user name and password before sending messages, impersonation is more difficult than with e-mail. Also, instant messaging software typically allows a user to define a list of "friends" (i.e., other registered users with whom the user wishes to communicate) and to reject or ignore messages sent by other users. Thus, the problem of unwanted messages is reduced.
Instant messaging is also appealing to some users because instant messaging client interfaces provide a more conversational and spontaneous feel than e-mail. For instance, instant messaging services generally provide information to a user about whether his friends are currently logged in or not, so that the user has some idea about whether a rapid response can be expected. The client can display messages from the user's friends on the user's screen without the user having to notice that a message has arrived or take any action to open the message. Many instant messaging clients also offer a "chat" mode, in which a window displays messages from two (or more) communicating users sequentially as they are entered; the user does not have to go through a sequence of steps to respond to a message or check to see if a reply to a previous message has come in.
Instant messaging services, however, generally limit the users who can exchange messages to a pool of subscribers, i.e., users who have accounts with the service provider. To communicate with non-subscribers (who may subscribe to a different instant messaging service or no instant messaging service), a user typically has to resort to another medium, such as e-mail, typically involving switching to a different program, protocol and user interface.
Some instant messaging services allow a non-subscriber to sign on as a guest for the limited purpose of corresponding with a particular subscriber, but this typically requires the subscriber and the guest to communicate via some other channel (e.g., e-mail) first, to arrange an instant messaging session. Various other demands may also be placed on the guest. For example, the guest generally has to use the service provider's instant messaging interface, which often requires the guest to download and install the service provider's software. The service provider may also request personal information (which the guest may not want to share) in the course of setting up an interface for the guest. Such obstacles limit the effectiveness of guest access to instant messaging services.
It would, therefore, be desirable to provide an instant messaging service that expanded a user's ability to communicate with users other than fellow subscribers to the service.

System and method for instant messaging using an e-mail protocol


A signal determining circuit determines the voltage of a control signal which is output according to a rotational angle of a thumb ring. When the determined voltage of the control signal is lower than a predetermined cutoff voltage, an armature of a switch means is made to contact a point of contact which is grounded, so that the control signal can be interrupted. On the other hand, when the determined voltage of the control signal is higher than the cutoff voltage, the armature of the switch means is made to contact the other point of contact so as to input the control signal to a driving circuit, and a servo motor is driven according to the control signal, so that a zoom lens can be moved to the tele side or the wide side. Thereby, it is possible to prevent the lens from operating incorrectly and to effectively eliminate an unstable area in a circuit which has a wide dynamic range.

1. Field of the Invention
The present invention relates generally to a lens controller, and more particularly to a lens controller which generates control signals for controlling a broadcast zoom lens used for a studio camera, a field camera, and the like.
2. Description of Related Art
Zoom speed controlling is usually performed in order to control the zooming of a large-sized lens by a servo-control for a studio camera and a field camera. A user performs the zooming operation by rotating a thumb ring of a zoom controller, which is attached to a grip of a pan/tilt handle. The zoom controller determines the rotational angle of the thumb ring by a potentiometer, and the direction in which the thumb ring is rotated from a neutral position determines the tele direction or the wide direction. The motor of the zoom lens is controlled so that as the rotational angle of the thumb ring increases, the zoom speed increases.
In a conventional zoom controller, however, the zoom controller must deal with a wide dynamic range (a wide variable range of the zoom speed) of which zoom speed ranges from a maximum speed for moving the lens over the whole movable range in a fraction of a second to a minimum speed for moving the lens over the whole movable range in several hundred seconds (e.g. 200 seconds). For this reason, the zooming must start when the control signal is several millivolts (mV). Thus, there is a problem in that the undesired zooming operation can occur due to small errors (displacement) and changes of the control signal, which are caused by the mechanical displacement of the potentiometer of the zoom controller, secular changes of the mechanical system in the zoom controller, drift of parts of the zoom controller, noise from the outside, and the like.


A knock detection apparatus which is capable of changing a knock control starting time period appropriately so as to prevent erroneous knock determination, to thereby expand a knock control range. A peak value acquisition unit acquires a peak value of a vibration of an internal combustion engine during each rotation cycle of a crankshaft of the engine. A background calculator calculates a background by averaging peak values acquired by the peak value acquisition unit. A knock determination unit performs knock determination based on whether a peak value acquired by the peak value acquisition unit is higher than a predetermined level above the background, and feedback controls knock in the engine according to a result of the knock determination. A temperature acquisition unit acquires a temperature of the engine during a start of the engine. A knock determination controller inhibits operation of the knock determination unit until a predetermined time period determined according to the engine temperature acquired by the temperature acquisition unit has elapsed.

1. Field of the Invention
This invention relates to a knock detection apparatus, and more particularly to a knock detection apparatus for calculating a threshold value for knock determination based on a detected knock signal from an internal combustion engine.
2. Description of the Related Art
There has been proposed a knock control method in which knock having occurred in an engine is detected, and ignition timing is controlled based on a detected knock condition (see e.g. Japanese Unexamined Patent Publication No. 08-218996). In this knock control method, only a frequency component which can contain vibration caused by engine knock is obtained by filtering an output from a knock sensor using a band pass filter (BPF), and a peak value of the frequency component is sampled whenever the TDC (top dead center) position of each cylinder is reached. Then, the sampled peak value is compared with an averaged value (hereinafter referred to as "background") of peak values sampled so far, and whether or not knock has occurred is determined based on whether the currently sampled peak value is higher than a predetermined level above the background, whereby the amount of ignition advance is feedback-controlled. The feedback control is performed such that if it is determined that knock has not occurred, ignition timing is progressively advanced, whereas if it is determined that knock has occurred, ignition timing is retarded.
By the way, the background is obtained by averaging sampled peak values as mentioned above. More specifically, a value obtained by subtracting the immediately preceding background from the current peak value is multiplied by a predetermined coefficient, and a value obtained by the multiplication is added to the immediately preceding background to thereby determine the current background, this value (updated value) being provided with an update guard value for preventing a sudden change of the background due to noise. Therefore, it takes time for the background to converge to a constant value at which the engine is started.
FIG. 34 is a diagram useful in explaining the convergence of background during the start of the engine. As shown in FIG. 34, sampling of peak values is started upon the start of the engine. However, since the background is obtained by averaging sampled peak values, it is updated whenever the TDC position of each cylinder is reached, whereby the background is caused to progressively converge to a peak value. For this reason, if knock determination is performed before the background has converged to the peak value (i.e. during a period F in FIG. 34), it can be determined that the peak value is higher than the predetermined level above the background without occurrence of knock, which causes erroneous determination that knock has occurred. To prevent this erroneous determination, it is a conventional practice to start the knock feedback control after the lapse of a predetermined time period, by taking a time period required for convergence of the background into consideration.
Further, although in the calculation of the background, the update guard value for preventing a sudden change of the background due to noise is provided as mentioned hereinabove, if a sudden change of the peak value is caused not by noise, but by a correct cause, the update guard value retards convergence of the background. To eliminate this inconvenience, it is conventional to change the update guard value according to engine speed and intake pipe pressure so as to prevent retardation of convergence of the background. For example, when engine speed or intake pipe pressure rises suddenly, the absolute value of the peak value also increases suddenly. In this case, since the change in the peak value is not due to noise, the update guard value is increased so as to enable the background to quickly converge to the peak value. This causes the background to converge to a predetermined value.
As described above, in the prior art, even when the background has actually converged to a peak value, knock feedback control is started after the lapse of a predetermined time period, resulting in a narrowed knock control range.
Further, at the start of the engine, it takes time for the background (threshold value) to converge, inhibiting knock determination from being performed before the background has converged.
Furthermore, in the prior art, the update guard value (upper limit value) is changed only based on engine speed and intake pipe pressure, but not changed even when the peak value has changed due to other factors except noise. Therefore, in the latter case, the convergence of the threshold value is retarded.

Knock detection apparatus and knock detection method


A diagnostic method for predicting whether a human tumor will be sensitive or resistant to treatment with tivozanib (AV-951) is disclosed. The method is based on measurement of macrophage content in a tissue sample from a tumor. Measurement of macrophage content can be based on analysis of macrophage marker gene expression, e.g., by RNA analysis or immunohistochemistry.

Most cancer drugs are effective in some patients, but not in others. This results from genetic variation among tumors, and can be observed even among tumors within the same patient. Variable patient response is particularly pronounced with respect to targeted therapeutics. Therefore, the full potential of targeted therapies cannot be realized without suitable tests for determining which patients will benefit from which drugs. According to the National Institutes of Health (NIH), the term "biomarker" is defined as "a characteristic that is objectively measured and evaluated as an indicator of normal biologic or pathogenic processes or pharmacological response to a therapeutic intervention."
The development of improved diagnostics based on the discovery of biomarkers has the potential to accelerate new drug development by identifying, in advance, those patients most likely to show a clinical response to a given drug. This would significantly reduce the size, length and cost of clinical trials. Technologies such as genomics, proteomics and molecular imaging currently enable rapid, sensitive and reliable detection of specific gene mutations, expression levels of particular genes, and other molecular biomarkers. In spite of the availability of various technologies for molecular characterization of tumors, the clinical utilization of cancer biomarkers remains largely unrealized because few cancer biomarkers have been discovered. For example, a recent review article states:                There is a critical need for expedited development of biomarkers and their use to improve diagnosis and treatment of cancer. (Cho, 2007, Molecular Cancer 6:25.)Another recent review article on cancer biomarkers contains the following comments:        The challenge is discovering cancer biomarkers. Although there have been clinical successes in targeting molecularly defined subsets of several tumor types—such as chronic myeloid leukemia, gastrointestinal stromal tumor, lung cancer and glioblastoma multiforme—using molecularly targeted agents, the ability to apply such successes in a broader context is severely limited by the lack of an efficient strategy to evaluate targeted agents in patients. The problem mainly lies in the inability to select patients with molecularly defined cancers for clinical trials to evaluate these exciting new drugs. The solution requires biomarkers that reliably identify those patients who are most likely to benefit from a particular agent. (Sawyers, 2008, Nature 452:548-552, at 548.)Comments such as the foregoing illustrate the recognition of a need for the discovery of clinically useful biomarkers and diagnostic methods based on such biomarkers.
There are three distinct types of cancer biomarkers: (1) prognostic biomarkers, (2) predictive biomarkers, and (3) pharmacodynamic (PD) biomarkers. A prognostic biomarker is used to classify a cancer, e.g., a solid tumor, according to aggressiveness, i.e., rate of growth and/or metastasis, and refractiveness to treatment. This is sometimes called distinguishing "good outcome" tumors from "poor outcome" tumors. A predictive biomarker is used to assess the probability that a particular patient will benefit from treatment with a particular drug. For example, patients with breast cancer in which the ERBB2 (HER2 or NEU) gene is amplified are likely to benefit from treatment with trastuzumab (HERCEPTIN®), whereas patients without ERBB2 gene amplification are unlikely to benefit from treatment with trastuzumab. A PD biomarker is an indication of the effect(s) of a drug on a patient while the patient is taking the drug. Accordingly, PD biomarkers often are used to guide dosage level and dosing frequency, during the early stages of clinical development of a new drug. For a discussion of cancer biomarkers, see, e.g., Sawyers, 2008, Nature 452:548-552.
Tivozanib (also known as AV-951) is a potent and selective small-molecule inhibitor of VEGF receptors 1, 2 and 3. Tivozanib exhibits picomolar inhibitory activity against all three receptors, and it exhibits antitumor activity in preclinical models (Nakamura et al., 2006, Cancer Res. 66:9134-9142). Tivozanib has yielded positive interim results in a 272-patient Phase 2 clinical trial (Bhargava et al., 2009, ASCO Genitourinary Cancers Symposium, Abstract No. 283).
Despite a large amount of pre-clinical and clinical research focused on VEGF-targeted therapy, the mechanisms responsible for the anti-tumor activity of anti-VEGF agents are not fully understood. As with other types of targeted therapy, some, but not all, patients benefit from tivozanib therapy. The complexity of VEGF biology makes the effectiveness of tivozanib against any given tumor unpredictable. Therefore, there is a need for diagnostic methods based on predictive biomarkers that can be used to identify patients with tumors that are likely (or unlikely) to respond to treatment with tivozanib.


A hardware and software co-simulation method for non-blocking cache access mechanism verification is provided. The method is applied for cache access mechanism verification. First, at least one way buffer is added into the software modeling, then the hardware and software modeling are simulated. Wherein, the hardware modeling issues a trigger event for reading request when one ‘outstanding miss’ occurs. At this moment, the software modeling stores the data of the address to be accessed into a way buffer. When the hardware modeling obtains the data from the main memory, it issues a trigger event for reading completion, and causes for writing the data from the way buffer into the data memory of the software modeling. The verification result of the software simulation is compared with the verification result of the hardware simulation.

1. Field of Invention
The present invention relates to a method for circuit verification. More particularly, the present invention relates to a hardware and software co-simulation method for verifying cache access mechanism.
2. Description of Related Art
With the help of computer science, designers can use programming languages to establish software modeling for software simulation during circuit designing. By means of software simulation, designers can verify whether the function (or behavior) of circuit being designed is correct or not. Besides, designers can use hardware description language (HDL) to establish hardware modeling for hardware simulation as well, such as performing a resistor-transistor layer (RTL) simulation. Likewise, designers can verify whether the function (or behavior) of circuit being designed is correct or not by means of hardware simulation.
Mostly, designers use both hardware simulation and software simulation to verify the correctness and efficiency properties of the designed circuit. Designers can further compare the respective verification results of hardware and software co-simulation to check the reliability of the simulations.
However, the behavior verification results between the hardware simulation and the software simulation for some circuits may be different. For example, in the same non-blocking cache in pipelined CPU, the behavior verification result of software simulation differs from that of hardware simulation. That is because the software modeling is of the instruction simulation mode, during its simulation, the actual time needed by main memory to answer the requited access is neglected. FIG. 1A to FIG. 1F indicate the change of the storage state of the data memory during simulation of the hardware modeling of non-blocking cache. Here, the instructions of "LDR R1, 0×1000—0000", "LDR R2, 0×2000—0000", "LDR R3, 0×3000—0000" and "LDR R4, 0 ×1000—0000" are taken as the test pattern needed by the simulating operation.
FIG. 1A illustrates the initial states of way 0 data memory W0 and way 1 data memory W1 in the hardware modeling of non-blocking cache. In FIG. 1B, when CPU executes instruction "LDR R1, 0×1000—0000", that is, data should be read from main memory address 0×1000—0000 and stored in register R1, because the data to be read does not exist in the cache, that is usually called 'miss', the data read from main memory at address 0×1000—0000 will first be stored into the cache of data memory W0 in order to be read by CPU.
When CPU executes instruction "LDR R2, 0×2000—0000" in succession, because the data to be read is 'miss', the data will be requested and read out from main memory at address 0×2000—0000, and then stored into non-used data memory W1 so as to be read by CPU, as illustrated in FIG. 1C. In sequence, when CPU executes instruction "LDR R3, 9×3000—0000", showed in FIG. 1D, because the data to be read is 'miss' either, likewise, a read request is first issued to the main memory. In FIG. 1E, because the cache is the non-blocking cache, CPU will continue executing the next instruction "LDR R4, 0×1000—0000" not necessary to wait for data return, even though the cache has not obtained the data from main memory address 0×3000—0000.
In FIG. 1E, because the previous instruction is 'miss', the hardware modeling issues a read request to the main memory for reading and not has obtained the data yet, there is still the data of address 0×1000—0000 in the cache of data memory W0. When executing instruction "LDR R4, 0×1000—0000", the CPU then obtains the data of address 0×1000—0000 from the cache of data memory W0, which is usually called 'hit'. After the cache obtains the data from main memory address 0×3000—0000, as illustrated in FIG. 1F, it will select the data memory W1, which has not been accessed for longest time in data memories W0 to W1, to store the data.
FIG. 2A to FIG. 2E indicate the change of the storage state of the data memory during simulation of the software modeling of non-blocking cache. Herein, in the same way, the instructions of "LDR R1, 0×1000—0000", "LDR R2, 0×2000—0000", "LDR R3, 0×3000—0000" and "LDR R4, 0×1000—0000" are taken as the test samples needed by the simulation.
FIG. 2A indicates the initial states of way 0 data memory W0 and way 1 data memory W1 in the software modeling of non-blocking cache. In FIG. 2B, when CPU executes instruction "LDR R1, 0×1000—0000", because of being 'miss', the data from the main memory address 0×1000—0000 is stored into the cache of data memory W0 in order to be read by the CPU. When the CPU executes instruction "LDR R2, 0×2000—0000" in succession, as shown in FIG. 2C, because the data to be read is 'miss', a read request for reading the main memory at address 0×2000—0000 is issued and the data of the address is read out and then stored into non-used data memory W1 so as to be read by CPU.
In sequence, when the CPU executes instruction "LDR R3, 0×3000—0000", as showed in FIG. 2D, because of the data being 'miss', likewise, a request for reading is issued to the main memory. However, since it is neglected for the actual time needed by the main memory to respond the access request during the simulation of software modeling, the cache immediately obtains the data from main memory at address 0×3000—0000 and stores the data into data memory W0, which has not been accessed for the longest time in the data memory. Then, as illustrated in FIG. 2E, when the instruction "LDR R4, 0×1000—0000" is executed, because of data to be read at 0×1000—0000 being 'miss', likewise, the data is requested and read from the main memory at address 0×1000—0000 and stored in data memory W1, which has not been accessed for the longest time in the data memories W0 to W1. Therefore, the behavior verification results between hardware simulation and software simulation of non-blocking cache are not the same, so that the comparison between their simulation results can not be done for hardware and software co-simulation.

Hardware and software co-simulation method for non-blocking cache access mechanism verification


This invention relates to novel nucleic acid sequences encoding three novel human phosphodiesterase (hPDE IV) isozymes. It also relates to polypeptides encoded by such sequences.

This invention relates to novel nucleic acid sequences encoding three novel human phosphodiesterase IV (hPDE IV) isozymes.
Cyclic nucleotide phosphodiesterases (PDE's) are a family of enzymes that catalyze the degradation of cyclic nucleotides. Cyclic nucleotides, particularly cAMP, are important intracellular second messengers, and PDEs are one cellular component that regulates their concentration. In recent years, five PDE enzymes (PDE I–PDE V), as well as many subtypes of these enzymes, have been defined based on substrat affinity and cofactor requirements (Beavo J A and Reifsnyder D H, Trends Pharmacol. Sci. 11:150 [1990]; Beavo J, in: Cyclic Nucleotide Phosphodiesterases: Structure, Regulation and Drug Action. Beavo J and Housley M D (Eds.). Wiley: Chichester, pp. 3–15 [1990]).
Theophylline, a general PDE inhibitor, has been widely used in the treatment of asthma. It has been speculated that selective inhibitors of PDE isozymes and their subtypes (particularly the cAMP-specific PDE IV) will lead to more effective therapy with fewer side effects (for reviews, see Wieshaar RE et al., J. Med. Chem., 28:537 [1985] and Giembycz M A, Biochem. Pharm., 43:2041 [1992], Lowe J A and Cheng J B, Drugs of the Future, 17:799–807 [1992]). However, even PDE IV selective drugs such as rolipram suffer from emetic side effects that limit their use. An even more selective approach is to inhibit individual subtypes of PDE IV, each one of which is expected to have its own tissue distribution. If the PDE IV isozyme responsible for efficacy is different from that causing side effects, an isozyme selective drug could separat therapeutic and side effects. The cloning and expression of the human PDE IVs would greatly aid the discovery of isozyme-selective inhibitors by providing purified isoenzymes to incorporate into drug assays.
Mammalian PDE IV, the homologue of the Drosophila Dunce gene (Chen C N et al., Proc. Nat. Acad. Sci. (USA) 83:9313 [1986]), is known to have four isoforms in the rat (Swinnen J V et al., Proc. Nat. Acad. Sci. (USA) 86:5325 [1989]). The cloning of one human isoform of PDE IV from monocytes was reported in 1990 (Uvi GP et al., Mol. Cell. Bio., 10:2678 [1990]). From Southern blot data, the authors concluded that this enzyme was probably the only PDE IV gene in humans, with the possible exception of one other isozyme. The same group has recently published the sequence of a second human isoform isolated from brain that they designate hPDE IV-B to distinguish it from the monocyte form, which they designate as hPDE IV-A (McLaughlin MM et al., J. Biol. Chem. 268:6470 [1993]). For clarity, we will use this nomenclature as well.
Our invention relates to the nucleic acid sequences encoding three novel human PDE IV isozymes generated by differential splicing from a single gene. We designate these isoforms as hPDE IV-B1, hPDE IV-B2 and hPDE IV-B3. The hPDE IV-B2 sequence encodes a polypeptide nearly identical to that reported for hPDE IV-B (McLaughlin MM et al., J. Biol. Chem. 268:6470 [1993]), and the hPOE IV-B2 splice variant represents the unspliced genomic sequence with respect to the differential splice site. Of the two other splice variants, hPDE IV-B1 encodes the longest polypeptide chain, as well as the N-terminal sequence homologous to its rat homologue, DPD (Colicelli J, et al., Proc. Nat. Acad. Sci. (USA) 86:3599 [1989]).
The novel human PDE IV DNA sequences and their encoded peptides may be used to screen for drugs that are selective for a particular human PDE IV isozyme. Such novel DNA sequences may also be used in assays to detect the presence of a particular POE IV isozyme in human cell lines, thus providing information regarding th tissue distribution of each isozyme and its biological relevance with respect to particular disease states.
The following abbreviations are used throughout this patent:
BALbronchoalveolar lavagebpbase pair(s)cAMPcyclic adenosine 3′,5′-monophosphatedNTP2′-deoxynucleoside-5′-triphosphatedATP2′-deoxyadenosine-5′-triphosphatedCTP2′-deoxycytidine-5′-triphosphatedGTP2′-deoxyguanidine-5′-triphosphatedTTP2′-deoxythymidine-5′-triphosphatehPDE IV-Ahuman monocyte PDE IVhPDE IV-Bhuman brain PDE IVhPDE IV-B1human brain PDE IV, splice variant 1hPDE IV-B2human brain PDE IV, splice variant 2hPDE IV-B3human brain PDE IV, splice variant 3kbkilobase(s)PCRpolymerase chain reactionPDEcyclic nucleotide phosphodiesterasePDE ICa2+/Calmodulin-dependent PDEPDE IIcGMP stimulated PDEPDE IIIcGMP inhibited PDEPDE IVhigh affinity cAMP-specific PDEPDE VcGMP specific PDERACERapid Amplification of cDNA EndsRTavian myeloblastosis virus (AMV) reverse transcriptaseRT-PCRPCR of RT-transcribed mRNASSC1X SSC = 0.15 M NaCl, 0.015 Na3 citrate pH 7.0
The nucleotides and amino acids represented in the various sequences contained herein have their usual single letter designations used routinely in the art.

Abstract: This invention also relates to an assay method for detecting the presence of such novel isozymes in human cells, and to a method of identifying compounds or other substances that inhibit or modify the activity of such isozymes.


An adaptor for a dust extractor is provided including a housing having a top portion and a bottom portion, a first aperture formed in the top portion of the housing, a second aperture formed in the bottom portion of the housing, and an adaptor catch having a first end and a second end. The adaptor catch is vertically slidable within the housing between a first catch position, where the first end projects through the first aperture, and a second catch position, where the first end is located flush with or inside of the housing. The second end of the adaptor catch is accessible through the second aperture. A first biasing mechanism biases the adaptor catch towards the second catch position.

One type of drill is a hammer drill which typically comprises an electric motor, a hammer mechanism and/or a rotary drive. The hammer drill is powered ether by an AC mains electric power supply or a battery attached to the hammer drill. A cutting tool, such as a drill bit, is supported within a tool holder mounted on the front of the hammer drill which is driven by the motor via either the rotary drive or the hammer mechanism or both to perform cutting operations. Such a hammer drill usually can operate in a hammer only mode, a drill only mode or a hammer and drill mode.
EP1157788 describes a typical example of hammer drill.
During the operation of a hammer drill, a large amount of dust can be generated. In addition to making the local vicinity dirty and clogging up the hammer drill, it can also be a health hazard to the operator of the hammer drill as the operator may breathe in the dust. As such it is desirable to collect the dust so that it can be safely disposed off.
One way of achieving this is by the use of a dust extractor. EP1245330 discloses an example of a dust extractor.
Dust extractors are attached to the body of a hammer drill. The dust extractor comprises a main body and a shroud, typically mounted on the end of a tubular telescopic arm which is attached to the main body, and which surrounds the cutting tool and engages with the work piece being cut. The dust extractor comprises a dust collection box, a filter mounted within the dust collection box and an air suction device. Whilst the hammer drill is in use, the air suction device is switched on. During use, the dust generated by the cutting tool cutting the work piece enters the shroud. The air suction device draws the air together with dust from within shroud, through the telescopic arm into the dust collection box. The air passes then through the filter, whilst the dust is trapped by the filter within the dust collection box. The clean air is then typically expelled from the dust extractor. Once the operation of the hammer is complete, the dust extraction box can be removed from the dust extractor and the dust removed from the dust collection box and safely disposed of.
In some designs dust extractors, the air suction device can be located remotely from the body. For example, the cooling fan of the electric motor of the hammer drill can be used as the air suction device and generate an air vacuum source which connects to the main body of the dust extractor. The air is drawn through the filter, out of the main body of the dust extractor and then into the housing of the hammer drill where it passes through the cooling fan of the hammer drill.
In alternative designs, a fan is rotatable mounted within the main body of the dust extractor adjacent the filter. The fan is rotatably driven by a motor to generate an air vacuum source and draw air from the shroud into the dust collection box and then through the filter before expelling it from the main housing. The fan can be rotatably driven by an electric motor mounted within the main housing of the dust extractor. Alternatively, the fan can be releasably attached to the spindle of the drive motor of the hammer drill. DE4024022 discloses such a dust extractor.
A problem associated with existing designs of dust extractor is that each particular design of dust extractor is intended to be used with only one specific design of hammer drill.