A milling tool having multiple cutting disks is disclosed. Each cutting disk is anchored into a flute on the milling tool with clamping screws. During use, the cutting disks naturally become dull. In a preferred embodiment, a single clamping screw is used to hold the cutting disk in place. The clamping screw is loosened and the cutting disk is rotated such that a new and sharp portion of the cutting disk is exposed for use. In an alternative embodiment, multiple clamping screws are used to secure the cutting disk into the flute. In the event a cutting disk becomes stuck in a flute, a clamping screw in a threaded bore coaxially aligned with the locating bore is used to push the cutting disk and eject it out of the flute. This design allows for many positions on the cutting disk to be used before the disk needs to be replaced, sharpened, or refurbished.

The early history of lenses is unknown. In 1845 an archeologist uncovered in what is now Iraq an ancient rock crystal ground to form a small convex lens, but there is no evidence that lenses were widely known or used in ancient times. An early investigation of the principles of lenses was made in the 11th century by Alhazen, a Persian physicist. Spectacles with convex lenses were in common use both in Europe and in China as early as the 13th century.
Zacharias Janssen, a Dutch optician, is credited with combining lenses to make a compound microscope about 1590. Galileo improved the telescope in 1609. The art of design and manufacture of lenses has progressed steadily since that time.
Ophthalmic Lenses are designed to refract light so that it reaches the retina. It is necessary for light rays to focus on each retina, in the back of our eyes, in order for us to see. When the eye's own optical system cannot refract light onto the retina, ophthalmic lenses are needed.
The main job of the ophthalmic lens is to manipulate light. Lenses are used for many reasons. The main reasons they are prescribed is for safety, vision, and comfort. Different materials are used for specific purposes and visual needs. Most ophthalmic lenses refract light rays to reach the retina, reflect uncomfortable or dangerous light rays, reflect annoying glare, absorb light for comfort or safety, and transmit light for better vision.
The most common reason lenses are prescribed is for vision. Three factors determine the prescription in a lens. They are the material (index of refraction), thickness, and curvature. In theory, lenses are considered as being prisms attached base-to-base or apex-to-apex. A convex lens (prisms base-to-base) magnifies images, and is used for the correction of Hyperopia or Presbyopia. A concave lens (apex-to-apex) minifies images, and is used for the correction of Myopia. Cylinder (toric) lenses are also used for the correction of astigmatism, and have different powers in different zones of the lens.
The design and production of lenses is a complex art and science. Glass and Plastic-type lenses, with the exception of polycarbonate, are made from a molding process. First, the lens designer calculates the best curvatures necessary for superior optical quality. Then, a computerized program attached to a digital file and lathe cuts the inside/top surface of the mold. This could be a single curvature for single vision lenses, or multiple curves for an aspheric lens or a progressive addition lens. Then, the back of the mold is typically attached and liquid plastic (monomers and polymers) are added. After the annealing and cooling process is complete, the lens is ready to be surfaced. Surfacing a lens means cutting curves into the back side to create the prescribed numbers, or spectacle prescription. In simple spherical curves, a steeper curve yields a stronger prescription and a flatter curve yield a weaker prescription. Once polished, the finished lens is ready to be edged for the shape of the frame. Many coatings and filters can be added to the lens to manipulate light in different ways, such as ultraviolet filters and scratch resistant coatings.
In milling the lens, typically a disk-like tool is used having a series of cutting edges located around the outer edge of the disk. These cutting edges can be made from a diamond or a diamond like substance and are typically brazed onto the disk. An example is Satisloh's 12 Blade fixed PCD insert milling wheel, model 92-009-346. However, to replace the cutting edges on this milling wheel, each cutting bit needs to be heated such that the brazing liquefies thereby allowing the cutting edge to be removed from the tool body. This process is both costly and time consuming.
Another drawback to using a disk with fixed cutting edges is the limited amount of the cutting edge that can be used before the cutting edges need to be sharpened or replaced when they can no longer be sharpened. Modern lens generators have a small footprint, which limits the amount the cutting tool may move relative to the lens. This limited amount of movement results in only a small portion of the cutting edge being used before the tool needs to be sharpened or replaced, which adds additional cost and time to the lens production process. To overcome this inefficiency in the production process, tools having quick replacement cutting edges have been developed. This design allows for the cutting edges to be rotated in place thereby moving a fresh and sharp section of the cutting edge to the point that contacts the lens. However, even these new designs have limitations. For instance, Satisloh's T66 Cutting Wheel with PCD inserts, model number 92-002-738, replaces typical fixed inserts with 8 replaceable inserts. This newer design provides an improvement over earlier designs, yet it still has drawbacks. For example, Satisloh's design only allows the cutting edges to be rotated to a clean cutting position up to three (3) times before the cutting edge must be removed and sharpened as suggested by the manufacturer. In addition, the cutting edges may only be sharpened up to 3 times, depending on the condition of the cutting edges, further limiting the cost and time advantages of this design.
Another example is Mapal's cutting wheel. This wheel also has several drawbacks. The cutting edge inserts are located off the center bore of the flute into which the cutting disk mounts. Variations in the bore of each flute results in inaccurate location of the cutting edges with regards to generating an effective and consistent radius during rotation. The cutting disks are secured with a screw and reverse clamp thread plate where the cutting disk is held in place with no more than three (3) threads on average, resulting in the cutting disk insert possibly becoming loose during operation. During use, the cutting disk insert may become stuck in the flute. Current cutting tools lack a release mechanism allowing for the safe release of a cutting disk in the event it becomes stuck. Due to the extreme sharp nature of the cutting edges, a user's hand or fingers could easily be cut while attempting to remove a stuck cutting disk insert from the flute. The clamp plates and center location bores are easily damaged during clamping and tool setting. Finally, clearance between flutes makes assembly and disassembly difficult and may result in injury to the user or damage to the cutting disk during insertion or removal of the cutting disk.
What is needed in the industry is a cutting wheel having replaceable cutting edges. A further benefit is a cutting wheel where the cutting edges are positionable to more than three (3) positions thereby extending the life of the tool as well as minimizing the costs associated with removal and replacement of the cutting tool as well as the costs associated with the sharpening of the edges themselves.

Milling tool with rotatable cutting disks


A lithographic manufacturing process is disclosed in which first information of a lithographic transfer function of a first lithographic projection apparatus is obtained. The information is compared with second information of a reference lithographic transfer function (e.g. of a second lithographic projection apparatus). The difference between the first and second information is calculated. Then, the change of machine settings for the first lithographic projection apparatus, needed to minimize the difference, is calculated and applied to the first lithographic projection apparatus. In an exemplary application, a match between the first and second lithographic projection apparatus of any pitch-dependency of feature errors is improved.

In general, a lithographic manufacturing process according to one embodiment of the invention comprises: providing a first lithographic projection apparatus comprising a projection system for projecting a patterned beam onto a target portion of a substrate, providing a substrate that is at least partially covered by a layer of radiation-sensitive material, providing a projection beam of radiation using a radiation system, using patterning structure to endow the projection beam with a pattern in its cross-section, projecting the patterned beam of radiation onto a target portion of the layer using the projection system to obtain a projected image, and providing a second lithographic projection apparatus for reference.
The term "patterning structure" as here employed should be broadly interpreted as referring to means that can be used to endow an incoming radiation beam with a patterned cross-section, corresponding to a pattern that is to be created in a target portion of the substrate; the term "light valve" can also be used in this context. Generally, the said pattern will correspond to a particular functional layer in a device being created in the target portion, such as an integrated circuit or other device (see below). Examples of such patterning structure include:                A mask. The concept of a mask is well known in lithography, and it includes mask types such as binary, alternating phase-shift, and attenuated phase-shift, as well as various hybrid mask types. Placement of such a mask in the radiation beam causes selective transmission (in the case of a transmissive mask) or reflection (in the case of a reflective mask) of the radiation impinging on the mask, according to the pattern on the mask. In the case of a mask, the support structure will generally be a mask table, which ensures that the mask can be held at a desired position in the incoming radiation beam, and that it can be moved relative to the beam if so desired.        A programmable mirror array. One example of such a device is a matrix-addressable surface having a viscoelastic control layer and a reflective surface. The basic principle behind such an apparatus is that (for example) addressed areas of the reflective surface reflect incident light as diffracted light, whereas unaddressed areas reflect incident light as undiffracted light. Using an appropriate filter, the said undiffracted light can be filtered out of the reflected beam, leaving only the diffracted light behind; in this manner, the beam becomes patterned according to the addressing pattern of the matrix-adressable surface. An alternative embodiment of a programmable mirror array employs a matrix arrangement of tiny mirrors, each of which can be individually tilted about an axis by applying a suitable localized electric field, or by employing piezoelectric actuation means. Once again, the mirrors are matrix-addressable, such that addressed mirrors will reflect an incoming radiation beam in a different direction to unaddressed mirrors; in this manner, the reflected beam is patterned according to the addressing pattern of the matrix-adressable mirrors. The required matrix addressing can be performed using suitable electronic means. In both of the situations described hereabove, the patterning structure can comprise one or more programmable mirror arrays. More information on mirror arrays as here referred to can be gleaned, for example, from U.S. Pat. No. 5,296,891 and U.S. Pat. No. 5,523,193, and PCT patent applications WO 98/38597 and WO 98/33096, which are incorporated herein by reference. In the case of a programmable mirror array, the said support structure may be embodied as a frame or table, for example, which may be fixed or movable as required.        A programmable LCD array. An example of such a construction is given in U.S. Pat. No. 5,229,872, which is incorporated herein by reference. As above, the support structure in this case may be embodied as a frame or table, for example, which may be fixed or movable as required.For purposes of simplicity, the rest of this text may, at certain locations, specifically direct itself to examples involving a mask and mask table; however, the general principles discussed in such instances should be seen in the broader context of the patterning structure as hereabove set forth.
Lithographic projection apparatus can be used, for example, in the manufacture of integrated circuits (ICs). In such a case, the patterning structure may generate a circuit pattern corresponding to an individual layer of the IC, and this pattern can be imaged onto a target portion (e.g. comprising one or more dies) on a substrate (silicon wafer) that has been coated with a layer of radiation-sensitive material (resist). In general, a single wafer will contain a whole network of adjacent target portions that are successively irradiated via the projection system, one at a time. In current apparatus, employing patterning by a mask on a mask table, a distinction can be made between two different types of machine. In one type of lithographic projection apparatus, each target portion is irradiated by exposing the entire mask pattern onto the target portion at one time; such an apparatus is commonly referred to as a wafer stepper. In an alternative apparatus—commonly referred to as a step-and-scan apparatus—each target portion is irradiated by progressively scanning the mask pattern under the projection beam in a given reference direction (the "scanning" direction) while synchronously scanning the substrate table parallel or anti-parallel to this direction; since, in general, the projection system will have a magnification factor M (generally <1), the speed V at which the substrate table is scanned will be a factor M times that at which the mask table is scanned. More information with regard to lithographic devices as here described can be gleaned, for example, from U.S. Pat. No. 6,046,792, incorporated herein by reference.
In a manufacturing process using a lithographic projection apparatus, a pattern (e.g. in a mask) is imaged onto a substrate that is at least partially covered by a layer of radiation-sensitive material (resist). Prior to this imaging step, the substrate may undergo various procedures, such as priming, resist coating and a soft bake. After exposure, the substrate may be subjected to other procedures, such as a post-exposure bake (PEB), development, a hard bake and measurement/inspection of the imaged features. This array of procedures is used as a basis to pattern an individual layer of a device, e.g. an IC. Such a patterned layer may then undergo various processes such as etching, ion-implantation (doping), metallization, oxidation, chemo-mechanical polishing, etc., all intended to finish off an individual layer. If several layers are required, then the whole procedure, or a variant thereof, will have to be repeated for each new layer. Eventually, an array of devices will be present on the substrate (wafer). These devices are then separated from one another by a technique such as dicing or sawing, whence the individual devices can be mounted on a carrier, connected to pins, etc. Further information regarding such processes can be obtained, for example, from the book "Microchip Fabrication: A Practical Guide to Semiconductor Processing", Third Edition, by Peter van Zant, McGraw Hill Publishing Co., 1997, ISBN 0-07-067250-4, incorporated herein by reference.
For the sake of simplicity, the projection system may hereinafter be referred to as the "lens"; however, this term should be broadly interpreted as encompassing various types of projection system, including refractive optics, reflective optics, and catadioptric systems, for example. The radiation system may also include components operating according to any of these design types for directing, shaping or controlling the projection beam of radiation, and such components may also be referred to below, collectively or singularly, as a "lens". Further, the lithographic apparatus may be of a type having two or more substrate tables (and/or two or more mask tables). In such "multiple stage" devices the additional tables may be used in parallel, or preparatory steps may be carried out on one or more tables while one or more other tables are being used for exposures. Dual stage lithographic apparatus are described, for example, in U.S. Pat. No. 5,969,441 and PCT Patent Application No. WO 98/40791, incorporated herein by reference.
A circuit pattern corresponding to an individual layer of an IC generally comprises a plurality of device patterns and interconnecting lines. Device patterns may comprise structures of different spatial arrangement such as, for example, line-space patterns ("bar patterns"), capacitor and/or bit line contacts, DRAM isolation patterns, and twin-hole patterns. Any such structure (of different spatial arrangement) is referred to hereinafter as a "feature". Fabrication of a circuit pattern involves the control of space tolerances between devices and interconnecting lines, between features, and between elements of a feature. In particular the control of space tolerance of the smallest space between two lines permitted in the fabrication of the device and/or of the smallest width of a line is of importance. Said smallest space and/or smallest width is referred to as the critical dimension ("CD"). A feature may comprise elements (such as, for example, bars) arranged in a spatially periodic manner. The length of the period associated with said spatially periodic arrangement is referred to hereinafter as the "pitch". Hence, it is possible to identify a pitch or a (limited) range of pitches for such a (periodic) feature; accordingly, in this specification reference may be made to the pitch of a feature. Generally, a distinction is made between "dense" features and "isolated" features. In the context of the present invention, a dense feature is a feature where the width of a feature element is of the order of the CD, and where the pitch is of the order of two to six times the CD. Similarly, an isolated feature is a feature comprising elements of a width of the order of the CD, and where the pitch is of the order of 6 or more times the CD. Besides circuit patterns, a feature in the context of at least one embodiment of the present invention may also relate to a test pattern for controlling a lithographic process step.
In lithography, a method known as CD-proximity matching is used to address a phenomenon known as the optical proximity effect. This effect is caused by the inherent difference in diffraction pattern for isolated features as compared to dense features. Generally, the optical proximity effect leads to a difference in critical dimension (CD) when dense and more isolated features are printed at the same time. A pitch dependence of CD will be referred to hereinafter as "CD-pitch anomaly". In the presence of CD-pitch anomaly the printed CD depends on the pitch (the inverse of the spatial frequency) at which elements of the dimension of the CD are arranged in a feature.
CD-pitch anomaly also depends on the illumination setting used. An "illumination setting" or an "illumination mode" in the context of the present invention should be interpreted throughout this specification and in the claims to comprise a setting of a preselected radiation intensity distribution in a pupil plane of the radiation system. Originally, so-called conventional illumination modes have been used which have a disc-like intensity distribution of the illumination radiation at the pupil of the radiation system. With the trend to imaging smaller features, the use of illumination settings providing annular or multi-pole intensity distributions in the pupil of the radiation system have become standard in order to improve the process window, i.e. exposure and focus latitude, for small features. However, CD-pitch anomaly becomes worse for off-axis illumination modes, such as annular illumination.
One solution to alleviate the occurrence of CD-pitch anomaly has been to apply Optical Proximity Correction (referred to hereinafter as "OPC") by biasing the different features on the reticle. For example, according to one form of biasing, the features are biased by making the lines of more isolated features on the reticle somewhat thicker so that, in the image on the substrate, they are printed with the same transverse dimension as the lines of dense features. In another form of biasing, an end correction is applied so that the lines of isolated or dense features are printed with the correct length. However, at smaller pitches and with off-axis illumination, the variation of the CD as a function of pitch is more pronounced and more non-linearly related to pitch than at larger pitches; consequently, more line biasing has to be applied at smaller pitches and the biasing becomes more complicated. OPC is discussed, for example, in SPIE Vol. 4000, pages 1015 to 1023, "Automatic parallel optical proximity correction and verification system", Watanabe et al. As will be appreciated, advanced software algorithms and very complex mask making is required for OPC. This has significantly increased costs of masks. Generally, in a high volume manufacturing site, different lithographic projection apparatus are to be used for a lithographic manufacturing process step involving OPC. In such a situation, matching of different lithographic projection apparatus such as to reduce CD variations is normally done for one selected feature type (for example, a dense or an isolated feature) by an adjustment of exposure energy at each of said different lithographic projection apparatus save the apparatus used for reference. Such a matching of lithographic apparatus is described, for example, in C. Lee et al., "Reducing CD variation via statistically matching steppers", Proceedings of the SPIE, Vol. 1261, 63–70 (1990) and in U.S. Pat. No. 5,586,059, incorporated herein by reference. Since the matching of printed CD is substantially effectuated for one selected feature type, there is the problem that the matching of CD for features with pitches other than the pitch of the feature selected for matching can be rather poor or even out of tolerance.

Lithographic manufacturing process, lithographic projection apparatus, and device manufactured thereby


A method of washing a piece of construction equipment includes washing a portion of the piece of construction equipment with water, collecting waste materials washed from the construction equipment in a bin, allowing liquid collected in the bin to drain into a receptacle having a sloped bottom for conveying the liquid to a sump, pumping the liquid from the sump, filtering the particulate matter pumped from the pump to recover clean water, and storing the recovered clean water for recycling in a tank. Filtering includes pumping the liquid from the sump to a first settlement tank and on to a second settlement tank though a fluid path having an upwardly extending baffle providing partial wall between the first and second settlement tanks and a downwardly extending baffle spaced from the upwardly extending baffle and extending into the second settlement tank wherein liquid cascades over the upwardly extending baffle and downwardly through a space between the upwardly extending baffle and the downwardly extending baffle such that the particulate matter is left behind in the first and second settlement tanks.

Concrete is one of the primary building materials used worldwide. One common form of concrete used in construction is "ready-mix" concrete, which is produced in accordance with a given formula at a plant and then trucked to a jobsite. At the jobsite, the concrete is off-loaded from the truck, as required to form a desired structure. Any excess or residual concrete left in the truck is then typically washed-out at the jobsite.
One current wash-out practice is to dig a pit in the ground and line it with plastic film. Ready-mix trucks dump any excess concrete into the pit and use roughly 15-20 gallons of water to rinse the truck and chute. The typical concrete pump will dump approximately ¼ to ½ a cubic yard of concrete into the pit and then require 30-50 gallons of water for rinsing off the pump truck. The result is not only a significant amount of wasted water, but a significant amount of water contaminated with caustic concrete waste. Furthermore, washout pits normally remain uncovered and if it rains, the washout pit may overflow and cause further contamination of the soil around the pit. This overflow water can also run into storm drains and on into rivers and bays, and possibly even into the ground water.
Eventually, a small front-end loader or the like is used to break up the waste concrete in the washout pit and remove it to be crushed and recycled. During this process the plastic liner is ruined and any remaining concrete-contaminated wastewater leaks into the soil.
One known solution to the problem of waste concrete is to wash-out ready-mix trucks into roll-off trash dumpsters. However, these types of dumpsters are not watertight and much of the wastewater leaks out and soaks into the soil. Furthermore, concrete pump trucks cannot use these dumpsters and therefore must dump their extra concrete waste and the resulting wastewater onto the ground next to the dumpster. Moreover, dumpsters are also subject to rain contamination and overflow.
On some large road jobs, or at extra large commercial job sites, contractors will sometimes dig out a large washout pit (approximately ½ to 1 acre in size) and set up several large evaporation pits. This technique allows for the washout of trucks in one location followed by wastewater evaporation and periodic waste concrete removal from the evaporation pits. These washout pits are too large and too costly to build and maintain for use in the construction of new home communities or at small commercial job sites. Additionally, the problems of rain overflow and wasted water are not addressed by this technique.
Hence, new solutions are required for conserving water and minimizing environmental impact during the wash-out of concrete pouring equipment at jobsites.

Systems and methods for washing-out concrete pouring equipment


Conduits for guiding the motion of an inner diameter shroud of a low pressure compressor of a gas turbine engine are disclosed. The inner diameter shroud has at least three slots formed in one or more radially inwardly extending flanges. Each of the conduits are configured to assemble with a respective one of the at least three slots. Each conduit comprises a bushing having a first panel, and the first panel is capable of being inserted in a respective one of the slots of the inner diameter shroud. The conduit further comprises a bracket capable of being attached to a bearing support of a fan intermediate case of the gas turbine engine. The bushing is capable of being attached to the bracket. A contact between the first panel and the at least one slot of the inner diameter shroud restricts a circumferential rotation of the inner diameter shroud with respect to a central axis of the gas turbine engine when the first panel is inserted in the at least one slot, but allows a radial motion of the inner diameter shroud with respect to the central axis.

Gas turbine engines, such as those used to provide thrust to an aircraft, are internal combustion engines that use air as the working fluid. In general, gas turbine engines may include, among other features, a fan section and a core engine located downstream of the fan section. In operation, air may be drawn into the engine and accelerated by the fan section, and a fraction of the indrawn air may be routed through a primary flow path defined by the core engine. In an upstream to downstream order, the core engine may include: 1) a compressor section which may include a low pressure compressor (LPC) and a high pressure compressor (HPC), 2) one or more combustors, 3) a turbine section, and 4) an exhaust nozzle. In the primary flow path, the air may first be compressed/pressurized in the compressor section and it may then be combusted with fuel in the combustor(s) to generate hot combustion gases. The hot combustion gases may then expand through the turbine section, where energy may be extracted to drive the rotation of the turbine section, the compressor section, and the fan section, as all may be mounted on one or more common shafts. The gases may then be exhausted through the exhaust nozzle to provide forward thrust to an associated aircraft, or to provide power if used in other applications.
The compressor section and the turbine section may include alternating stages of stator assemblies with stationary airfoils (vanes) and rotor assemblies with rotating airfoils (blades). In rotor assemblies, the blades may be attached to a rotating disk or hub. In stator assemblies, the vanes may extend between two stationary (non-rotating) shrouds, including an inner diameter (ID) shroud and an outer diameter (OD) shroud located radially outward of the ID shroud with respect to an engine central axis.
Depending on the local temperatures and the materials making up the core engine components, the core engine components may undergo subtle thermal expansion or contraction. Unlike other regions of the core engine which are exposed to hot compressed and/or combusted gases, the inlet stator assembly of the LPC is exposed to lower temperature air that has not yet undergone compression or combustion. Due to the relatively low gas temperatures in the local flow path, the inner diameter (ID) shroud of the inlet stator assembly may be formed from lightweight materials such as aluminum which has a higher coefficient of thermal expansion (CTE) than higher strength metals such as titanium and nickel based alloys used for other engine components. Therefore, the ID shroud of the LPC inlet stator assembly may expand and contract more readily in response to temperature fluctuations than titanium- or nickel alloy-based components of the gas turbine engine.
At certain flight points, the ID shroud of the LPC inlet stator assembly may be driven to radial contraction due to exposure to a relatively cold gas path. However, the ID shroud may be mated to an upstream titanium-based bearing support and fan intermediate case which may be driven to radial expansion due to exposure to hot engine oil. The conflicting expansion/contraction tendencies and expansion/contraction rates may lead to a thermal fight between the fan intermediate case/bearing support and the ID shroud of the LPC inlet stator assembly. This occurrence may ultimately lead to stresses and/or low cycle fatigue issues in the ID shroud of the LPC inlet stator assembly.
Thus, there is a need for engine designs which mitigate or eliminate stresses caused by thermal growth mismatches between fan intermediate cases/bearing supports and ID shrouds of LPC shrouds of LPC inlet stator assemblies. U.S. Pat. No. 7,025,563 discloses the use of an outer shroud seal to accommodate thermal growth mismatches between an aluminum-based outer shroud of a LPC exit stator assembly and other titanium-based stator assembly components. While effective, the design does not address thermal fight issues between fan intermediate cases and ID shrouds of LPC inlet stator assemblies. The present disclosure addresses this problem.

Conduit for guiding low pressure compressor inner diameter shroud motion


An inherent shutdown system for a nuclear reactor having neutron absorbing rods affixed to an armature which is held in an upper position by a magnetic flux flowing through a Curie temperature material. The Curie temperature material is fixedly positioned about the exterior of an inner duct in an annular region through which reactor coolant flows. Elongated fuel rods extending from within the core upwardly toward the Curie temperature material are preferably disposed within the annular region. Upon abnormal conditions which result in high neutron flux and coolant temperature, the Curie material loses its magnetic permeability, breaking the magnetic flux path and allowing the armature and absorber rods to drop into the core, thus shutting down the fissioning reaction. The armature and absorber rods are retrieved by lowering the housing for the electromagnet forming coils which create a magnetic flux path which includes the inner duct wall. The coil housing then is raised, resetting the armature.

1. Field of the Invention
This invention relates to control structures for nuclear reactors and more particularly provides an inherent shutdown system responsive to off-normal operational core characteristics.
2. Description of the Prior Art
The fissioning reaction within a nuclear core can be controlled by selective addition and removal of neutron absorbing material, typically in the form of absorber rods. Rapid shutdown of the reactor during off-normal operating conditions is important, and recent systems have been proposed which inherently respond to such conditions to drop or otherwise insert absorber rods into the core. Typical of such systems is that described in U.S. Pat. No. 3,976,540 which discloses an inherent shutdown system including a neutron absorbing mass held above a core through a magnetic flux. The magnetic flux circuit includes a ferromagnetic Curie point material which inherently responds to a selected high temperature so as to lower its magnetic permeability and break the magnetic circuit, thereby allowing the magnet and a fixed absorber mass to fall, under the force of gravity and a spring assist, into the core region. Curie temperature materials are well known which can be selected or alloyed to have a Curie point temperature.
While this and similar teachings appear to provide desired inherent shutdown capabilities, improvements can be made. For example, the discussed patent mixes coolant passing over fuel rods with cooling flowing through a vacant central region into which the absorber mass will drop. In the event of overtemperature conditions in the fuel rods, the coolant flowing about the fuel rods will heat up but be diluted by the cooler coolant flowing through the vacant region, thus slowing down the response time to reach the selected Curie temperature. Further, the teaching proposes lateral support of the magnet assembly and a fixed absorber mass which is dependent upon frictional characteristics and may thus require a larger holding force than otherwise necessary. The system additionally requires springs to laterally displace a portion of the holding structure to allow free fall of the absorber mass. The system also drops the magnet as well as the absorber mass into the core, exposing the magnet to a high and potentially damaging neutron flux upon insertion. Also, a mechanical manipulator is required to retrieve the magnet and absorber mass subsequent to insertion. And, relatively large surface area contact exists among the absorber mass and magnet and the structures which retain them in an upper position, potentially resulting in self-welding during normal operation which would defeat the insertion. Additionally, to test the system the Curie temperature material must be resistance heated. Alternatively, although not taught, if the magnet is an electromagnet allowing testing by cutting of the electrical power, the power leads will drop along the magnet, creating high mechanical loadings and exposing the leads to a high neutron flux and temperature upon insertion into the core.
It is thus desirable to provide an improved inherent shutdown system which alleviates these, and other deficiencies, in the present nuclear reactor inherent shutdown systems.


A method and device for an inter-RAT handover for a PS service in a dual-mode RNC are disclosed in the present invention, which are used to support an inter-RAT handover optimization flow of the PS service in the dual-mode RNC, thereby solving the problem that the current inter-RAT handover optimization flow does not support the PS handover. With the present invention, in the inter-RAT handover optimization flow, an inter-RAT relocation flow and a radio resource allocation flow of a destination system are executed in parallel, and an encryption indication is sent to a central network through inter-RAT relocation required message; a BSC forwards user data to the central network according to the encryption indication.

In a radio communication network, the mode of different radio access technologies operating simultaneously is a common network operation mode. In the network with different radio access technologies operating simultaneously, in order to implement network complementation when different radio access technologies operate simultaneously, handover of services between different radio access technologies is a basic function. Currently, conventional inter-RAT handover flow is: to inform a destination system to prepare radio resources through inter-RAT relocation message, and after the destination system returns relocation response message, initiate the inter-RAT handover flow, thus a handover delay is relatively longer; with regard to a high-speed mobile User Equipment (UE), the handover with a long delay easily causes a dropped call, which influences the handover performance and Quality of Service (Qos).
Iur-g is an interface between an RNC and a BSC, an inter-RAT handover optimization flow based on the Iur-g interface is disclosed in certain enterprise standards currently (with reference to FIG. 1), a radio resource allocation flow of a destination system is advanced before an inter-RAT relocation flow, an air-interface handover flow and the inter-RAT relocation flow are performed in parallel, thereby enhancing an inter-RAT handover success rate and reducing an inter-RAT handover delay. However, since an encryption node of the PS service in the 2nd Generation (2G) communication system is a Servicing GPRS Support Node (SGSN), and a 2G radio access network does not know the encryption situation, therefore, the optimization flow is only applied to the CS handover.
In a dual mode RNC, since the Radio Network Controller (RNC) in the 3rd Generation (3G) communication system and the Base Station Controller (BSC) in the 2nd Generation (2G) communication system are combined into one, and information between dual mode radio access networks can be interacted inside the dual mode RNC.

Method and device for inter-system handover for packet switch service in dual-mode radio network controller


An elevated retainer is disclosed for retaining roofing tile that include tile lugs against a roofing surface. The elevated retainer includes a retainer head, the retainer head having a base and a top. Extending from the retainer head, is a reinforcing strip with as nail slot. The reinforcing strip being adapted for extending in generally parallel to the roofing surface when the base of the retainer head is placed against the roofing surface. The device also includes lug retainer that engages lugs of the roofing tile while the tile lies between the reinforcing strip and the lug retainer.

(a) Field of the Invention
This invention generally relates to a device and method for installing and retaining roofing tile on a roof. More particularly, but not by way of limitation, to a elevated retainer that engages portions of roofing tile and enhances the nailing, retention, and cooperation of the roofing tiles improve installation productivity and resistance of the installations to winds.
(b) Discussion of Known Art
Tile has been a well-regarded roofing material for centuries. The aesthetics qualities and durability of tile roofing materials have been balanced against the cost associated with the materials and skill required to install these tile roofing. Perhaps the most popular types of tile used today include Roman, Greek, French, Interlocking, Flat Slab (Dowager Queen), and Spanish or Mission styles of tile.
The installation of the roofing tile is carried out over the roofing surface, which is typically plywood covered with a waterproofing membrane and a wood batten or batten and lath matrix. A horizontal line, made with the use of chalk line, is used as a guide for the batten or lath and the positioning of the tile. The roofing tile typically includes an upper edge, or "head", and a lower edge, or "nose". The upper edge is designed for mounting at a higher location on the roof than the lower edge. At least one nail hole is typically found at about the middle of the tile, next to the upper edge. At least one "head lug" is found near the upper edge of the tile; the head lugs provide mechanical engagement over battens or lath, or provide a stable foundation for attachment to the roofing surface.
A significant problem encountered in the use of tile roofing is the roof's resistance to high winds. Often times high winds will lift the tiles from the roof, causing the tiles tear away from the roof. What typically occurs is that the nose of the tile is lifted by the wind and the tile flipped up or rotated about its attachment point near the head of the tile.
A common problem associated with the use of battens is that they can capture moisture and debris that may have been trapped between the tiles and the roofing surface. This leads to rapid deterioration of the roofing surface. The battens are often mounted on top of counter battens or lath that have been mounted perpendicularly to the horizontal battens. This raising of the battens is designed minimize the capture of moisture along the horizontal batten. A problem associated with this solution is that it further raises the head of the tiles and provides a passage for wind under the tiles, and thus facilitates the lifting of the roofing tiles in a storm.
There are known clips that can be used to facilitate the installation of roofing tile, but these do not fully cooperate with the features of the tile to provide an inherently secure attachment of the tile, and do not enhance resistance to lifting of the tile in high winds.


The invention relates to a circuit breaker that can be switched between an ON position and an OFF position, such that in the OFF position an interruption path comprising an arcing space is formed. The circuit breaker comprises a storage volume for a quenching gas, which is in gaseous communication with the arcing space and has an inlet port for the quenching gas. The inlet port also has a valve comprising an obturator, and the obturator has a heat-insulating coating.

A switch of this type is known, for example, from European patent applications EP 0696040 A1 and EP 0951039 A1, the contents and disclosure of which are fully incorporated in the scope of the present patent application, by way of reference thereto.
During the switching of high currents by switches of this type, specifically in the event of a short-circuit, high pressures in the range of 10 to 100 bar and temperatures in excess of 2300° K. typically occur in the insulating gas contained in a pressure chamber and in a return duct. In the case of very high currents, specifically in a range in excess of 250 kA and/or in switches of compact construction, temperatures of up to 3000° K. or higher may occur. As a result, the obturator of a non-return valve, configured as a metal ring, which is fitted to the outlet of the return duct to the heating chamber for the insulating gas may undergo plastic strain, such that the non-return valve is no longer capable of satisfactorily fulfilling its function.
Tests have demonstrated that plastic strain of this type can be prevented, or at least substantially reduced, by the use of an obturator of more solid construction; however, this is associated with a simultaneous increase in the inertia of the non-return valve such that, upon actuation, the closure of the return duct by raid valve is insufficiently rapid, thereby permitting the unwanted escape of insulating gas from the heating chamber.
A puffer-type circuit breaker is known from DE 29604500 U1, in which the puffer piston is coated with a layer of heat-resistant plastic, such as PTFE or polyamide, in order to provide electrical shielding in relation to the contact piece or to prevent the formation of root points for the switching arc on the puffer piston.
Accordingly, the object of the invention, is the proposal of a circuit breaker which eliminates the disadvantages described above.


A sequential memory (10) uses interleaved memories (12a-b) with associated output buffers (22a-b) to accomplish high data rates. Data access control circuitry (18) and bank select circuitry (20) control the order in which the memory banks (12a-b) are written to and read from. Output buffer circuits (22a-b) allow a data word to be read instantaneously after it is written to the sequential memory (10).

Sequential memories, such as FIFOs and LIFOs, are often used as a buffer between two circuits. These memories are referred to as a "sequential" because data is output in a predetermined sequence corresponding to the order in which it is was input. Sequential memories allow equipment operating at different input/output speeds to communicate with one another. Early sequential memories comprised shift registers which serially stored incoming data units at a desired speed and read out the stored data units at a different speed. Generally, shift register implementations of sequential memories are of limited storage and have unacceptable delay times, and therefore are unsuitable for many operations. More recently, random access memories have been developed in which pointers are used to implement the first-in, first-out or last-in, last-out I/O sequence.
While CMOS SRAM implementations are widely used, it would be desirable to increase the data rate at which a single sequential memory can operate. In CMOS SRAMs, a write to memory involves three distinct operations. First, the write bitlines are precharged to one of the voltage rails (normally V.sub.cc), after which the precharge is disabled. The two bitlines (D and D) are pulled to V.sub.cc and ground, or vice versa, depending upon the value to be written to the memory. Finally, the wordline and column select of the cell to be written to are pulsed to complete the write operation to the selected cell.
Importantly, all of the write bitlines are precharged between writing. Precharging the bitlines is thus a power-consuming operation. Also, every cell which has a common wordline with the cell being written to is selected. Data stored in these cells are not overwritten, however, because the respective bitlines are not selected by the column select, and therefore, are still at the rail. Precharging the bitlines creates a high current situation due to the large number of cells that are pulsed. The operations for reading from the memory are very similar to the operations for writing to the memory, and therefore exhibit similar power losses due to the nature of the CMOS RAM cell.
To reduce the power consumption problems, a designer will normally resort to a block select architecture to reduce bitline length (which typically improves access time) and wordline length. The SRAM is thus divided into two or more separate arrays; once the first array is full, writing begins on the second array, and so on. Naturally, there is a trade-off between the number of blocks and the level of multiplexing necessary to combine the blocks together.
Nonetheless, because of the three operations needed to read to or write from a memory cell, the data rate of the sequential memory is limited. Typically, a write operation requires about ten nanoseconds to perform the write and to recover from the write (i.e., to precharge the write bitlines to one of the voltage rails to prepare for the next write). Thus, improvements to the speed of the sequential memory are more or less tied to improvements made to the speed of CMOS SRAM arrays.
Therefore, there is a need to provide a sequential memory having a high data rate using available technology.


An FEA having a novel structure using an n.sup.+ shallow junction region, which operates with small voltages and increases emission current and a method for manufacturing the same. A tip is formed on a first conductive type semiconductor substrate, a first impurity region having a high impurity concentration is formed in the upper portion of the semiconductor substrate wherein first conductive type impurities are implanted, and a second conductive type second impurity region is formed in the surface of the semiconductor substrate around the tip and on the first impurity region. Also, a second conductive type shallow junction region is formed in the surface portion of the tip, an insulation layer including a pin hole which exposes the tip is formed on the semiconductor substrate, and a conductive layer having an opening corresponding to the pin hole of the insulation layer is formed on the insulation layer. When electrons are emitted by a tunneling effect, the required voltages to be applied are lowered. Since the tip can be manufactured by a self-aligned manner, the manufacturing process becomes simplified.

The present invention relates to a field emitter array (FEA) and method for manufacturing the same, and more particularly, to a novel field emitter array having a shallow junction, and a method for manufacturing the same.
In response to a rapidly increasing demand for spacesaving, personal displays which serve as the primary information transmission interface between humans and computers (and other types of computerized devices), various types of flat screen or flat panel displays have been developed to replace conventional display devices, particularly CRTs, which are relatively large, bulky, and obtrusive. Examples of these flat panel displays include a plasma display, liquid crystal display, fluorescent display and field emission display. Among the flat panel displays, the field emission display has been under active research, since it can be driven by a relatively low power and can easily embody color images.
The field emission display emits electrons by a field emitter array on which the cathode tips (each of which is the source of the electrical field per a unit pixel) are highly integrated, and the emitted electrons are captured on the fluorescent layer to thereby form a pixel.
The cathode tips are arranged in a closed and limited space which is maintained at a high vacuum state for enabling the electrons to be emitted easily. The cathode tips have been mainly manufactured using a metal. In recent years, there have been suggested a number of methods for manufacturing micro-tips using developments in semiconductor manufacturing technology.
For example, Smith et al. have suggested a field emission cathode structure and manufacturing method thereof by using a single crystalline semiconductor substrate, in U.S. Pat. No. 3,970,887. Also, Greene et al. have suggested an FEA having a pyramidal field emission cathode structure on a single crystalline substrate by using a p-n junction structure, in U.S. Pat. No. 4,513,308.
FIG. 1 is a cross-sectional view of the FEA disclosed by Greene et al.
Referring to FIG. 1, an insulation layer 22 having multiple pin holes is formed in a matrix pattern on a p-type semiconductor substrate 14, and an n-type pyramidal tip 16 including the p-type semiconductor substrate 14 and a p-n junction 18 is formed in the pin holes. Here, a metallic electrode 20 is formed on the insulation layer 22, and a lower electrode 28 is provided in the lower portion of semiconductor substrate 14. When a voltage 26 is applied through the metallic electrode 20 and the lower electrode 28 so that the p-n junction may be forward biased, a predetermined amount of electrons are emitted from a tip depending on the applied voltage 26. The emitted electrons are captured in a fluorescent layer (not shown), and the fluorescent layer is excited to then form a pixel.
Most current research is concentrated on a field emission device using sharp tips by which the field emission device can operate in a high voltage emission and high-temperature environment with minimal power loss. However, the device requires high applied voltages.
Meanwhile, a method for manufacturing a field emission device has been recently proposed, which can emit electrons with low applied voltages by using a shallow silicon p-n junction region without tips (see Jung Y. Ea et al., "Silicon Avalanche Cathodes and Their Characteristics," IEEE Transactions on Electron Devices, Vol. 38, No. 10, October 1991). According to the referenced thesis, electrons are emitted through an n.sup.+ shallow junction region by a tunneling effect. However, when an FEA is manufactured by this method, after forming an opening by a patterning method, impurities are implanted therein to form a shallow junction region, which complicates the manufacturing process. Moreover, in the case of manufacturing a cathode array in which multiple field emission devices are integrated, it is difficult to manufacture such devices so as to have consistent characteristics on a single substrate.

Method for manufacturing field emitter array


A device for use in stimulating blood flow and providing stress relief. The device includes curved sides shaped to permit a user to rock back and forth on a flat surface. Five pair of handles are cut through the sides at various positions to help the user maintain a secure position while seated on the device and to facilitate aggressive modes of exercise. The handles are teardrop shaped to allow the user to select a gripping position wherein the gripping surface is generally perpendicular to the direction of pull. The device is designed to rock backwards and remain in that position, thereby placing the user in a supine position and raising the user's feet above his head. While so positioned, the user may perform many different exercises or may simply assume the supine position and rest while gravity drains the blood and fluid from her lower extremities. The user may also enjoy cardiovascular stimulation and stress relief when rocking the device.

The ever-increasing urbanization and mechanization of modern society has led to a corresponding increase in the stress experienced by its members. Physicians and physical fitness experts have long known that regular physical exercise can relieve such stress by increasing blood flow to the brain. For those who cannot engage in strenuous exercise, whether by infirmity or by time constraints, doctors recommend that these persons at least put their feet up above the level of their heart for a few minutes each day. This position allows blood and fluid to drain from the lower extremities and bathe the brain in oxygen and nutrients. Not only does this position tend to reduce stress by relaxing the body, it also provides a measure of cardiovascular exercise because the heart must pump harder to provide blood to the lower extremities.
A variety of devices to facilitate upside down relaxation and/or exercise have been developed by the art. For example, one popular product includes boots attachable to a horizontal bar so that the wearer may hang upside down. Similarly, exercise benches having an elevated end equipped with a bar or other means to restrain a user's feet above his head are used for vigorous exercise in many gyms.
For more casual uses, chairs which rock backward until the user's feet are positioned over his head have been disclosed. These chairs promote relaxation as well as exercise, and are known to promote good health by stimulating the flow of blood to the user's head. U.S. Pat. No. 4,367,870 to Birch, and U.S. Pat. No. 4,902,003 to Buoni disclose such devices.
Significantly, the invertible exercise chairs of the prior art have not provided handholds to permit a user to stabilize his position within the device. This limits the positions which can easily be obtained by failing to provide adequate means for stabilizing the user in the chair.
A need therefore exists for an exercise chair which provides a safe, stable base from which a user can engage in upside down exercise and/or relaxation, with handholds to facilitate stabilizing the user in the chair. The present invention addresses that need.


A textile printing method includes heating a cloth, and applying an ink composition onto the heated cloth by ejecting the ink composition from an ink jet head. The ink composition contains resin fine particles and has a viscosity of 4.5 mPa·s or less at 40° C. and a surface tension of 28 mN/m or less at 40° C.

1. Technical Field
The present invention relates to a textile printing method.
2. Related Art
A textile printing method has been known for printing images on cloth, such as textile fabrics, knitting, and nonwoven fabrics. In recent years, an ink jet printing method has been studied as a textile printing method from the viewpoint of efficiently using textile printing ink compositions (hereinafter often simply referred to as ink). In an ink jet textile printing method incorporating the ink jet method, ink is applied onto a cloth by being ejected through a nozzle of an ink jet head, thus forming an ink coating on the cloth.
The ink used in such an ink jet textile printing method may contain a coloring material, such as a pigment or a dye, a dispersant (surfactant), and a solvent, such as water or an organic solvent. Pigments are generally superior to dyes in terms of color fastness of the printed image to light and other properties, and there is disclosed a pigment textile printing method using a pigment as a coloring material (JP-A-2014-163021).
In this ink jet textile printing method, however, ink does not permeate sufficiently into the cloth, and accordingly, the fastness to laundering or rubbing of the printed image on the cloth is not satisfactory.


A touch panel is constructed of a top sheet member having a resistive membrane on its inner surface and a base sheet member having a resistive membrane on its inner surface, the top and base sheet members facing each other with dot spacers being located in between. The top sheet member is formed by laminating a bulge-resistant film, a polarizing plate, a quarter wavelength plate, and a light isotropic film in this order from above. A PET film which is not heat-treated so as to have a higher thermal contraction rate than the other members of the top sheet member underneath such as the polarizing plate, is used as the bulge-resistant film. Since the bulge-resistant film contracts more than the polarizing plate under a high ambient temperature, after the ambient temperature returns to normal, the bulge-resistant film does not become slack against the polarizing plate. Accordingly, the top sheet member can be kept from bulging outward.

1. Field of the Invention
The present invention relates to a glare-resistant touch panel, and more particularly relates to a technique for improving the operability of the touch panel in use environments that involve relatively high temperatures.
2. Description of the Related Art
A typical touch panel is constructed of an ultrathin glass plate (base sheet member) and a flexible transparent resin film (top sheet member) that are set facing each other and have resistive membranes respectively on their opposed surfaces, with spacers being placed in between the two sheet members in order to provide a certain spacing.
With an ever-widening range of applications of such touch panels, the demand for products that provide new additional values is growing in recent years. As an example, for combined use with a liquid crystal display (LCD) panel equipped in an outdoor-use device such as a car navigation system, a glare-resistant touch panel which is coated with a film of polarizer on its surface has been devised to keep the visibility of the display of the LCD panel from decreasing due to irregular reflections of incident light.
The polarizer used here is generally made of a resin film. Such a polarizing resin film has a thermal linear expansion coefficient eight to nine times that of glass which forms the base sheet member.
This large difference in thermal linear expansion coefficient between the top and base sheet members causes the following problems. As the temperature rises, the whole top sheet member including the polarizer bulges outward, thereby seriously deforming the touch panel. Besides, the operability of the touch panel decreases, as the space between the top and base sheet members widens and forces the user to apply a greater pressure to operate the touch panel. Given the recent trend toward larger touch panels with upsizing of LCD panels, the amount of outward bulge of the top sheet member is likely to increase, which will further degrade the touch panel""s operability.
This problem can be overcome by coating the upper surface of the polarizer with a resin film whose thermal linear expansion coefficient is lower than that of the polarizer, to keep the polarizer from bulging outward. An experiment on operability was conducted using a touch panel in which a PET (polyethylene terephthalate) film was adhered to the upper surface of the polarizer as a bulge-resistant film. As a result, the touch panel demonstrated high operability in a normal range of ambient temperatures. However, when left standing at a high ambient temperature over 60xc2x0 C. for a long time and then removed from that atmosphere and put in a normal temperature (around 25xc2x0 C.), the touch panel bulged upward and became seriously deformed, resulting in poor operability.
Inside a car parked in an outdoor parking lot under the scorching sun, the ambient temperature can easily reach as high as 80xc2x0 C. especially near a dashboard. If a car navigation system equipped with a touch panel is left in such a hostile condition, the top sheet member of the touch panel will bulge upward greatly, causing a significant decrease in operability.
In view of the above problems, the present invention aims to provide a touch panel whose appearance and operability are not impaired even after being left in high temperature environments, despite its use of a polarizer in a top sheet member to ensure visibility outdoors.
The above object can be achieved by a resistive-membrane touch panel including: a first sheet member having a first resistive membrane on a main surface thereof; a second sheet member that is flexible and has a second resistive membrane on a main surface thereof, the second sheet member being opposed to the first sheet member with a spacer interposed in between in such a manner that the second resistive membrane and the first resistive membrane face each other with a certain spacing therebetween; and a third sheet member that is laminated on an outer main surface of the second sheet member, wherein the second sheet member has a polarizing property, and the third sheet member has a thermal contraction rate no lower than a thermal contraction rate of the second sheet member.
Since the second sheet member has the polarizing property, the touch panel is guarded against glare. When such a touch panel is mounted on the front of a display panel such as an LCD panel, the visibility of the content displayed on the display panel is improved. Also, even when the second sheet member and the third sheet member contract in a high ambient temperature, after the ambient temperature returns to normal the third sheet member will not become slack against the second sheet member, because the thermal contraction rate of the third sheet member is equal to or larger than that of the second sheet member underneath it. Hence the outward bulge of the touch panel is effectively suppressed, and its appearance and operability is maintained regardless of temperature variations.
Here, the third sheet member may have a lower thermal linear expansion coefficient than the second sheet member. Even when the second sheet member is expanding to bulge outward as the ambient temperature rises, the third sheet member with the lower thermal linear expansion coefficient serves to suppress such an outward bulge of the second sheet member, so that the distance between the first and second sheet members will not widen substantially. As a result, the appearance and operability of the touch panel can be maintained regardless of temperature variations.
Here, the second sheet member and the third sheet member may be adhered with an adhesive that has a stress relieving property. The adhesive layer formed as such can absorb thermal stress growing between the second and third sheet members at elevated temperatures. Accordingly, no deviation from alignment will occur between the second and third sheet members, so that the operability of the touch panel can be maintained. Here, the viscoelasticity of the stress relieving adhesive is preferably in a range of 1.0xc3x97105dyn/cm2 to 1.2xc3x97106dyn/cm2. Also, the third sheet member may be coated with a hard coating material on its surface which is to be adhered to the second sheet member. In so doing, the adhesion of the third sheet member with the stress relieving adhesive is strengthened, which improves the durability of the touch panel.
Here, the third sheet member may have a lower hygroscopic linear expansion coefficient than the second sheet member. Even when the second sheet member is expanding to bulge outward due to moisture absorption, the third sheet member with the lower hygroscopic linear expansion coefficient serves to keep the second sheet member from bulging outward. Thus, the outward bulge of the touch panel due to moisture absorption can be effectively suppressed.


A microscope having little damage such as deformation, discoloration or the like given to a sample is disclosed. This microscope comprises an illuminance reducing unit for reducing illuminance of an illumination light on the sample. Assuming that a time width where illuminance is at a level enough for displaying an image of the sample is TF, a time width where illuminance is lower than the level enough for displaying an image of the sample is TN, and a value xcex1 is as follows:

1. Field of the Invention
The present invention relates to a microscope such as an industrial microscope or the like.
2. Related Background Art
With an increased demand for optical microscopes of high resolving power in recent years, shortening of a wavelength to be used has progressed.
Constitution of a conventional microscope is simply explained as follows. An illumination light emitted from a light source is transmitted through an illuminating lens, and then made incident on a half mirror. A part of the illumination light made incident on the half mirror, which has been reflected by the half mirror, is transmitted through an objective lens to illuminate a sample placed on a stage. Assuming that a direction of an optical axis is Z and two directions orthogonal to each other on a plane are X and Y, the plane being orthogonal to the Z direction, the stage can be moved in the X, Y and Z directions by a stage driving system.
An observed light reflected on the sample is transmitted through the objective lens, and then made incident on the half mirror. After having passed through the half mirror, the observed light is transmitted through an image-forming lens to form an image on an image sensor. An output signal from the image sensor is converted into a video signal by a video signal processing circuit, and then transferred to a monitor. Thus, an image of the sample is displayed on the monitor.
In such a conventional microscope, when an observer watched the image of the sample placed nearly in a static state for a long time, the sample was continuously irradiated with illumination lights, and damage such as deformation, discoloration or the like occurred in the sample. The damage can be attributed to a gradual increase in energy of a light projected to the sample. Such a phenomenon was especially conspicuous in a laser-scanning microscope for converging illumination lights in a very small spot.
Light energy on the sample, i.e., a quantity of an illumination light to be projected, can be obtained by a product of illuminance and irradiation time. A damage degree of the sample has a correlation with this quantity of the illumination light to be projected. In other words, with an increase in the quantity of an illumination light to be projected, a damage of the sample is larger. With a reduction in the quantity of the same, a damage is smaller. If a damage of the sample is large, not only reproducibility will be reduced when the sample is observed again and measured but also a quality of the sample as a product will be reduced. If the sample is a living being such as a microorganism, the living being may die.
It is an object of the present invention to provide a microscope capable of reducing damage such as deformation, discoloration or the like given to a sample.
In accordance with a first aspect of the invention, a microscope is disclosed, which comprises: a light source; an illumination optical system for irradiating a sample with an illumination light emitted from the light source; a stage for placing the sample; an image-forming optical system for collecting an observed light exiting from the sample; a detector for detecting the observed light passing through the image-forming optical system; a processing unit for processing a signal from the detector; a display for displaying an image of the sample based on a video signal from the processing unit; and an illuminance reducing unit for reducing illuminance of the illumination light on the sample to be lower than a specified value enough for observation by the display. With this microscope, by operating the illuminance reducing unit at a specified timing according to conditions including a movement of the stage or the like, it is possible to prevent inconveniences such as damage given to the sample by an excessive quantity of illumination light made incident on the same.
In accordance with a second aspect of the invention, a microscope is disclosed, which comprises: a light source; an illumination optical system for irradiating a sample with an illumination light emitted from the light source; a stage for placing the sample; a stage driving system for driving the stage; an image-forming optical system for collecting an observed light exiting from the sample; a detector for detecting the observed light passing through the image-forming optical system; a processing unit for processing a signal from the detector; and a monitor for displaying an image of the sample based on a video signal from the processing unit. The microscope further comprises illuminance reducing means for reducing illuminance of the illumination light on the sample, and is characterized in that assuming that a time width where illuminance is at a level enough for displaying an image of the sample is TF, and a time width where illuminance is lower than the level for displaying an image of the sample is TN, and a value a is as follows:
xcex1=TF/(TF+TN)xe2x80x83xe2x80x83(1)
the value xcex1 is changed by the illuminance reducing means according to a velocity of the stage, and the monitor (or display) displays a still picture of the sample for a period of TN, the still picture being one before the time width TN.
In this case, the illumination reducing means can set the value xcex1 to 0 while the stage is stopped, and to 1 while the stage is on the move.
With the foregoing constitution, since the irradiation quantity of illumination light in the same sample face is reduced, damage given to the sample is reduced. Next, an operation of the microscope of the invention will be described in detail. Generally, a sample placed on the stage of the microscope such as an industrial microscope is a static object. In other words, the sample unless a microorganism or the like never moves around itself.
Thus, while the stage where the sample has been placed is stopped, no change occurs in an image of the sample displayed on the monitor. Even while the stage is not completely stopped, if a velocity of a movement thereof is relatively low, a latest still picture may be displayed on the monitor while updating the same. In this way, a state is realized, which is nearly the same as that of displaying a motion picture (live image) of the sample in real time.
For example, consideration is given to a case where while the stage is in a stopped state, in other words while a stage velocity is 0, a monitor screen is frozen (fixed) without displaying the motion picture of the sample on the monitor, and the still picture of the sample is displayed. In this case, the stage is stopped and, at the instant of the stoppage thereof or after the passage of specified time, illuminance of an illumination light reaching the sample is reduced. As a result, damage given to the sample can be prevented.
On the monitor (or display), an image immediately before reduction of the illuminance is displayed as a still picture. In other words, the monitor screen is made frozen. Thus, no inconveniences occur for observation or measuring.
On the other hand, if the movement of the stage is started again, the illuminance of the illumination light reaching the sample is immediately restored to a normal value, and a motion picture of the sample is displayed on the monitor.
Here, the stopped state of the stage means that no displacement occurs in the stage not only in directions (X, and Y directions) orthogonal to an optical axis but also in a direction of the optical axis (Z direction). Thus, since the stage is not in a stopped state in a step of searching a desired position on the sample (moving step in X and Y directions) or in a step of adjusting a focus position (moving step in Z direction), the motion picture is displayed on the monitor. After the above operations are finished, then the stage is placed in a stopped state for the first time, and the still picture is displayed on the monitor.
Displacement of the stage can be easily detected by using a displacement gauge such as an encoder, an interferometer or the like. Also, in the case of using an electric stage, stage displacement can be detected based on existence of an operation of a stage driving motor.
Furthermore, reduction of the illuminance of the illumination light reaching the sample can be achieved by reducing an output of the light source or stopping the same. This can also be achieved by using a shutter to cut off the illumination light. Other than these, the illumination light may be cut off by using polarization to rotate a polarizing plate or a wavelength plate, alternatively by electrically modulating a liquid crystal wavelength plate.
Thus, with the present invention, according to a stage velocity v, the illuminance of the illumination light reaching the sample is adjusted, in other words, the value a in the expression (1) is changed.
In accordance with a third aspect of the invention, a microscope is disclosed, which comprises: a light source; an illumination optical system for irradiating a sample with an illumination light emitted from the light source; a stage for placing the sample; a stage driving system for driving the stage; an image-forming optical system for collecting an observed light exiting from the sample; a detector for detecting the observed light passing through the image-forming optical system; a processing unit for processing a signal from the detector; and a monitor for displaying an image of the sample based on a video signal from the processing unit. The microscope further comprises: illuminance reducing means for reducing illuminance of the illumination light on the sample; and a switch for performing switching between a continuous mode and an intermittent mode, the continuous mode being for displaying a video signal as a motion picture on the monitor, the video signal being one when illuminance is at a level enough for displaying an image of the sample, and the intermittent mode for a video signal as a still picture on the monitor while updating the same by using the illuminance reducing means to intermittently reduce illuminance, the video signal being one immediately before illuminance is set lower than the level enough for displaying an image of the sample.
In this case, the microscope further comprises displacement detecting means for detecting the displacement of the sample, and it is preferred that when the sample is displaced, the continuous mode should be set irrespective of a position of the switch.
With the foregoing constitution, damage given to the sample can be reduced by reducing an irradiation quantity of illumination light for a sample face. Next, an operation of the microscope of the invention will be described in detail. Generally, in any fields, an industrial field, a biological field or otherwise, with the microscope, since observation accuracy must be maintained for image observation, illuminance should not be reduced unnecessarily. As described above, however, an observer may need to observe an image of the sample placed in a near static state for a long time.
Thus, if the observer determines no necessity of continuous illumination or image capturing (continuous mode), by using the switch to make switching to the intermittent mode for intermittently performing illumination and image capturing, an irradiation quantity to the sample is reduced and, accordingly, damage given to the sample can be prevented. Subsequently, when an image is changed every moment, for example the sample is moved or, a focus is changed, the intermittent mode may be changed to the continuous mode by switching the switch. In this case, since cancellation of the intermittent mode depends on determination by the observer, priority is placed on relative sample damage reduction.
On the other hand, for placing priority on relative sample observation, detection may be performed for sample displacement, and the intermittent mode may be forcibly canceled when sample displacement is detected.
In accordance with a fourth aspect of the invention, a microscope is disclosed, which comprises: a light source; an illumination optical system for irradiating a sample with an illumination light from the light source; a stage for placing the sample; an image-forming optical system for collecting an observed light exiting from the sample; a detector for detecting the observed light passing through the image-forming optical system; a processing unit for processing a signal from the detector; and a monitor for displaying an image of the sample based on a video signal from the processing unit. The microscope is characterized in that a change amount of a video signal entered into the processing unit is detected, illuminance of the illumination light on the sample is reduced to a level for detecting the change amount of the video signal when the change amount of the video signal is smaller than a predetermined value, the video signal immediately before reduction of the illuminance is sent as a still picture to the monitor, the illuminance is set to the level enough for displaying an image of the sample when the change amount of the video signal is equal to the predetermined value or larger, and the video signal at this time is sent as a motion picture to the monitor.
With the foregoing constitution, an irradiation quantity of illumination light for the sample is reduced, and damage given to the sample can be reduced. Next, an operation of the microscope of the invention will be described in detail. In the microscope, illuminance should not be reduced unnecessarily for performing image observation. But an observer may need to watch an image of the sample placed in a near static state for a long time.
Thus, at the instant of this state or after the passage of predetermined time, by dimming the illumination light, damage given to the sample can be prevented. In this case, on the monitor, an image immediately before dimming is displayed in a frozen (fixed) manner. Accordingly, since no change occurs in the image, any inconveniences can be prevented for observation. Also, since the illuminance is reduced, damage given to the sample can be prevented.
Then, if a change occurs in the image, a screen on the monitor is immediately returned to a motion picture (live image).
In this case, for detecting changes in the image, image capturing is constantly executed. In other words, usually, image capturing and corresponding displaying on the monitor are both executed. During dimming, image capturing is executed, but no corresponding displaying is executed on the monitor. Then, determination is always performed as to existence of a change in the image by image capturing. If no image changes are determined, then image capturing in a dimmed state is continued. If an image change is determined, a motion picture is displayed on the monitor.
Thus, if there are no substantial changes in the image on the monitor, illumination of the sample is dimmed. If the image is changed every moment, for example during searching of a desired position on the sample, during adjusting of a focus position, while a living being as a sample is alive and moving or the like, a motion picture is always displayed on the monitor. Conversely, if the sample becomes static, for example when position adjusting, focus adjusting or the like is finished, the process changes to a dimmed state.
In this case, a unit constitution for detecting image changes should preferably include a memory for storing image data of a plurality of frames, and an electric processing system for comparing images with each other based on information thereof and determining a change.
In accordance with a fifth aspect of the invention, a microscope is disclosed, which comprises: a light source; an illumination optical system for irradiating a sample with an illumination light emitted from the light source; a stage for placing the sample; an image-forming optical system for collecting an observed light exiting from the sample; a detector for detecting the observed light passing through the image-forming optical system; a processing unit for processing a signal from the detector; and a monitor for displaying an image of the sample based on a video signal from the processing unit. The microscope further comprises: illuminance reducing means for reducing illuminance of the illumination light on the sample; and control means for detecting a change amount of the video signal entered into the processing unit and controlling the illuminance reducing means and the processing unit according to the change amount.
With the foregoing constitution, by reducing an irradiation quantity of illumination light to the sample face, damage given to the sample can be reduced. Next, an operation of the microscope of the invention will be described in detail. In the microscope, illuminance should not be reduced unnecessarily for performing image observation. But an observer may need to watch an image of the sample placed in a near static state for a long time. In such a case, substantially no changes occur in an image on the monitor.
Thus, at the instant of the above state or after the passage of predetermined time, by reducing illuminance of the illumination light, damage given to the sample can be prevented. At this time, on the monitor, an image immediately before the illuminance is reduced is displayed in a frozen (fixed) manner. In this way, since no changes occur in the image, any inconveniences can be prevented for the observer. Also, since the illuminance is reduced, damage given to the sample can be reduced.
Then, if any changes occur in the image, a screen on the monitor is immediately returned to a motion picture (live image).
In this case, for detecting an image change, short-time image capturing is performed at every constant interval of time even while the image is frozen. Then, determination is made as to a change in the image around this time interval. If no image changes are determined, then only intermittent image capturing is continued. If an image change is determined, then only continuous image capturing is carried out to return to the motion picture.
Thus, if there are no substantial changes in the image on the monitor, since the sample is illuminated intermittently, an irradiation quantity of illumination light is reduced. If the image is changed every moment, for example during searching of a desired position on the sample, during adjusting of a focus position, or while a living being as a sample or the like is alive and moving, the motion picture is always displayed on the monitor. Conversely, if the sample becomes static, for example when position adjusting or focus adjusting is finished, the process proceeds to an intermittent image capturing state.
A unit constitution for detecting image changes should preferably include, for example a memory for storing image data of a plurality of screens, and an electric processing system for comparing images with each other based on information thereof and determining a change.

Abstract: the value xcex1 is changed according to a velocity of a stage or the like. A monitor displays a still picture of the sample for a period of TN, the still picture being one before the time width TN.


A method for preparing polybutadiene having controlled molecular weight and high 1,4-cis content over 95% in the presence of a diethylzinc compound as a cocatalyst (i.e., alkylating agent) and molecular-weight-controlling agent, in which the molecular weight of the polybutadiene is controlled by variating the added amount of the diethylzinc compound without deterioration of 1,4-cis content nor polymerization yield, thus guaranteeing the optimum processability and physical properties of polymer according to the use purpose.

The present invention generally relates to a method for preparing polybutadiene having controlled molecular weight and high 1,4-cis content over 95% and, more particularly, to a method for polymerizing 1,3-butadiene in the presence of an organonickel compound and borontrifluoride etherate using a diethylzinc compound as an alkylating and molecular-weight-controlling agent to control the molecular weight of the resulting polymer simply by varying the amount of the diethylzinc compound, thereby enhancing the properties of the polymer such as processability or strength without deteriorating 1,4-cis content nor polymerization yield.
According to the conventional method of controlling the molecular weight of high 1,4-cis polybutadiene (hereinafter, referred to as xe2x80x9chigh-cis BRxe2x80x9d), for example, U.S. Pat. No. 5,100,982 discloses a method of using organonickel compound, organoaluminum compound and borontrifluoride etherate as a main catalyst, together with halogen-substituted phenol derivative as an additive to control the molecular weight and the molecular weight distribution of the high-cis BR.
U.S. Pat. No. 5,451,646 also discloses a method of using organonickel compound, organoaluminum compound and fluorine containing compound as a main catalyst, together with p-styrenated diphenyl amine to control the molecular weight of the high-cis BR, thereby improving the processability.
Further, Japanese Patent Laid-open Sho 53-51286 describes a method of preparing high-cis BR with a narrow molecular weight distribution using nickel compound, boron compound, alkyllithium and alkylbenzene sulfonate.
In addition, U.S. Pat. No. 4,533,711 discloses a method of further extending the molecular weight distribution of high-cis BR, wherein rare earth metal compound belonging to the atomic number of 57 to 71, organoaluminum compound and halogenated aluminum compound are used as a main catalyst, while using organoaluminum hydrides or hydrocarbons containing an activated hydrogen compound as an additive.
However, the above-described conventional methods of controlling the molecular weight in preparing high-cis BR are problematic in that the yield and the 1,4-cis content are lowered with great complexity of the process for industrial production.
Typically, the molecular weight as well as the molecular weight distribution is directly concerned with the processability and physical properties of polymer. Considering the above-mentioned problem, there is a need for rubbers having a low molecular weight and a considerably high molecular weight distribution in the manufacture of tires with improved processability, and rubbers having a high molecular weight and a low molecular weight distribution in the manufacture of tires with excellent physical properties such as high shock resistance and high tensile strength.
Accordingly, the inventors of this invention have attempted to solve the above-mentioned problems concerning the control of molecular weight in preparation of high-cis BR and contrived a method for preparing high-cis BR using a diethylzinc compound instead of an organoaluminum compound as an alkylating agent and molecular weight controlling agent, thereby readily controlling the molecular weight of high-cis BR based on the added amount of the diethylzinc compound without deteriorating 1,4-cis content nor polymerization yield.
It is an object of the present invention to provide a method for preparing polybutadiene having controlled molecular weight and high 1,4-cis content, in which a diethylzinc compound is added as an alkylating agent and molecular weight controlling agent without another additive to reduce the complexity of the process and control the molecular weight of high-cis BR without deteriorating polymerization yield nor 1,4-cis content, thus optimizing the processability and physical properties of rubber.
To achieve the above object of the present invention, there is provided a method for preparing polybutadiene having controlled molecular weight and high 1,4-cis content from polymerization of 1,3-butadiene using a catalyst obtained by aging a mixture of an organonickel compound, borontrifluoride etherate, and additionally a diethylzinc compound used as an alkylating agent and molecular-weight-controlling agent.
Now, the present invention will be described in further detail as set forth hereunder.
The present invention is directed to a method for regulating the catalyst activity based on the added amount of a diethylzinc compound and thereby controlling the molecular weight of high-cis BR that affects the processability and physical properties of rubbers, without deteriorating polymerization yield nor 1,4-cis content.
The catalyst as used herein comprises an organonickel compound, boron trifluoride etherate, and a diethylzinc compound used as an alkylating agent and molecular-weight-controlling agent.
According to the present invention, the high-cis BR has a higher molecular weight with an increase in the added amount of the diethylzinc compound, which tendency similarly appears in the conventional polymerization of 1,3-butadiene using a triethylaluminum compound as an alkylating agent.
Preferably, the diethylzinc compound is added in a molar ratio of 2 to 15 per 1 mole of nickel catalyst. If the molar ratio of such amount is less than 2 per 1 mole of nickel catalyst, the catalyst activity is deteriorated with a rapid drop of polymerization yield. But, in case of exceeding the molar ratio of 15, a color of the catalyst is susceptible to be changed into dark black and caused a precipitation due to over-reduction reaction during the aging step, which makes it impossible to weight the catalyst accurately or results in discoloration of high-cis BR.
As for the organonickel compound of the catalyst, compounds having a ligand that has a good solubility in non-polar solvents are preferred. For example, such compounds include nickel hexanoate, nickel heptanoate, nickel octanoate, nickel 2-ethylhexanoate, nickel naphthenate, nickel versatate, nickel stearate, nickel bis (2,2,6,6-tetramethyl-3,5-heptanedionate), preferably those containing at least 6 carbon atoms.
The borontrifluoride etherate composing the catalyst is a complex of an ether compound, the examples of which may include dimethyl ether, diethyl ether, dibutyl ether, tetrahydrofuran, dihexyl ether, dioctyl ether, and methyl t-butyl ether.
In line with the process of aging the Ziegler-Natta catalyst, it is prerequisite that the solvent used for aging the catalyst should not be reactive to the catalyst. Preferably, the catalyst-aging solvent is selected from the group consisting of cyclohexane, hexane, heptane and toluene.
It is preferable that the mixing ratio of organonickel compound, borontrifluoride etherate and diethylzinc compound in the catalyst is determined as follows: the molar ratio of diethylzinc compound to nickel compound is 2:1 to 15:1; the molar ratio of boron trifluoride etherate to organozinc compound is 0.7:1 to 5:1; the molar ratio of boron trifluoride etherate to nickel compound is 1:1 to 30:1.
The sequential order of adding the individual catalysts in preparation of the aged catalyst is as follows: a light-green colored nickel catalyst solution (in cyclohexane) containing 1,3-butadiene is added to a catalyst reactor under the nitrogen atmosphere, and then borontrifluoride etherate and the diethylzinc compound functioned as an alkylating agent and molecular weight controlling agent according to the present invention are introduced.
Since the sequential order of adding each catalyst significantly affects the properties of the final product, high-cis BR, extreme caution should be exercised in observing such sequential adding order.
Meanwhile, the temperature and time related to aging of the catalyst also affect the properties of high-cis BR; the appropriate aging time ranges from 5 minutes to 2 hours, while the aging temperature is preferably in the range of xe2x88x9220 to 60xc2x0 C.
Then, 1,3-butadiene and the aged Ziegler-Natta catalyst are admixed with a polymerization solvent to initiate polymerization. Since the polymerization solvent used for this invention may significantly affect the polymerization, it should be added to the reactor after oxygen and water are entirely removed.
Preferably, the polymerization solvent as used herein is a non-polar solvent, such as a cyclohexane, heptane, hexane, benzene, and toluene.
The polymerization is preferably initiated under the high-purity nitrogen atmosphere in the reaction temperature range from the room temperature to 100xc2x0 C. for 2 hours in the presence of an appropriate catalyst to attain the desired product with a yield of at least 90%.
After the reaction is completed, reaction terminator, for example, polyoxyethyleneglycolether organophosphate and 2,6-di-t-butyl-p-cresol are added to the reaction mixture, followed by precipitation in methyl alcohol or ethyl alcohol to obtain the final product.

Method for preparing polybutadiene having controlled molecular weight and high 1,4-cis content