Light input from a first optical fiber is split up into two orthogonally-polarized beams by a polarizing prism. Their polarization planes are rotated by a 45-degree Faraday rotator. The beams are refracted by a birefringent wedge as extraordinary light, and finally output to a fourth optical fiber. The light output from the fourth optical fiber is refracted by a birefringent wedge as ordinary light, and enters a second optical fiber. Similarly, the light from the second optical fiber is led to a third optical fiber, thereby implementing a capability of an optical circulator. Light output from the first optical fiber can be input to the third optical fiber by inverting a rotation angle of the 45-degree Faraday rotator. As a result, it serves as a magneto-optical switch.

1. Field of the Invention
The present invention relates to an optical device, and more particularly to an optical device implemented as an optical circulator and a magneto-optical switch.
2. Description of the Related Art
As interest in optical communication increases, the demand for an optical device of high performance, low price, and small size has become greater in recent years, in order to implement optical communications.
FIGS. 1A and 1B are schematic diagrams showing a conventional optical circulator or magneto-optical switch.
The optical circulator or the magneto-optical switch having a configuration similar to that of the optical circulator is implemented by using the non-reciprocal characteristics and inversion of magnetization of a 45-degree Faraday rotator. Basically, it is configured as shown in FIG. 1A.
The optical device shown in FIG. 1A comprises fibers 1006-1 through 1006-4 for inputting/outputting light, lenses 1005-1 through 1005-4 for collimating or focusing light, prisms 1001 and 1004 for splitting/combining light depending on a polarization state, a half-wave plate 1002 and a 45-degree Faraday rotator 1003, both of which are arranged between the prisms 1001 and 1004.
The prisms 1001 and 1004 split input light into two orthogonally-polarized components, and output the parallel beams along respective optical paths. A multilayer interference film is normally used as a means for splitting polarized light. The two prisms 1001 and 1004 are arranged facing each other, and the half-wave plate 1002 for reciprocally rotating a polarization plane by 45 degrees and the 45-degree Faraday rotator 1003 are inserted in between them. If the light proceeds from the fiber 1006-1 to the right in FIG. 1A, the rotation angles of the polarization planes of the polarized components split by the prism 1001 are rotated in the same direction by 45 degrees by both the half-wave plate 1002 and 45-degree Faraday rotator 1003, so that the total rotation angles are 45 degrees plus 45 degrees which equals 90 degrees. On the contrary, if the light proceeds from the optical fiber 1006-4 to the left, the polarization planes are rotated by 45 degrees by the 45-degree Faraday rotator 1003, and counter-rotated by 45 degrees by the half-wave plate 1002, so that the rotation angles are 45 degrees minus 45 degrees which equals 0. Accordingly, light from the fiber 1006-1 proceeds to the fiber 1006-4; light from the fiber 1006-4 proceeds to the fiber 1006-2; light from the fiber 1006-2 proceeds to the fiber 1006-3; and light from the fiber 1006-3 proceeds to the fiber 1006-1. In this way, the capability of the optical circulator can be implemented.
In the meantime, if the electromagnet of the 45-degree Faraday rotator is supplied with an electronic current thereby inverting its magnetization, the Faraday rotation angle is inverted. As a result, the light proceeding from the fiber 1006-4 to the fiber 1006-2, will proceed to the fiber 1006-1, thereby implementing the capability of the magneto-optical switch.
In this configuration, however, cross talk may occur due to the elliptical polarization caused by the 45-degree Faraday rotator, incompleteness of the splitting of the polarized light by the prism, etc. Normally, the amount of cross talk is approximately -25 to -30 dB.
To solve this problem, the optical circulator shown in FIG. 1B was proposed.
In the configuration shown in FIG. 1B, fibers 1010-1 through 1010-4 for inputting and outputting light are arranged, and lenses 1011-1 through 1011-4 collimate or focus the light. Birefringent crystals 1013 and 1014 are arranged so that they face the lenses 1011-1 through 1011-4. In addition, another birefringent crystal 1012 is arranged between the birefringent crystals 1013 and 1014. Half-wave plates 1016-1 through 1016-4 which are arranged in the respective optical paths, and 45-degree Faraday rotators 1015-1 and 1015-2 are inserted between the birefringent crystals 1012 and 1013, 1012 and 1014 respectively.
In FIG. 1B, light input from optical fiber 1010-1 or 1010-2 is split by the birefringent crystal 1013 according to the polarization, and two polarized beams whose polarization planes are orthogonal are polarization-rotated by the respective half-wave plates 1016-1 and 1016-2, so that they will be in the same orientation. After their polarization planes are rotated by the 45-degree Faraday rotator 1015-1, the beams are each refracted in particular directions by the birefringent crystal 1012, and these two polarized beams are again polarization-rotated by the respective half-wave plates 1016-3 and 1016-4, so that they become orthogonal. Then, after their polarization planes are rotated by the 45-degree Faraday rotator 1015-2, they are re-combined into a single beam by the birefringent crystal 1014, and output. Since the polarization direction of light in the central birefringent crystal 1012 differs by 90 degrees in the reverse direction, the light deviates from the optical path in the forward direction and becomes a different beam of light to be output. In this configuration, two non-reciprocal portions are included. Assuming that the cross talk caused by one of the non-reciprocal portions is one hundredth, the cross talk caused by passing through the two non-reciprocal portions will be one ten-thousandth. That is, the cross talk can be reduced significantly.
As described above, cross talk occurs due to the elliptical polarization caused by the 45-degree Faraday rotator and the incompleteness of the splitting of the polarized light by a prism, as in the configuration shown in FIG. 1A. Therefore, the amount of cross talk in FIG. 1B is doubled to approximately -50 to -60 dB, and this amount of cross talk exceeds that of an allowable range for practical use.
However, although the problem of cross talk is solved in the configuration shown in FIG. 1B, the number of components and their total size become large. As a result, the optical device itself becomes expensive.


A potent serine protease inhibitor capable of inhibiting Factor VIIa, Factor XIa, plasma kallikrein, or plasmin is provided. The inhibitor is provided in a pharmaceutical composition for treatment of diseases where inhibition of Factor VIIa, Factor XIa, plasma kallikrein, or plasmin is indicated.

Thrombosis accounts for about 40% of the deaths in the United States. Current treatments for thrombotic disorders involve the use of anticoagulant drugs (e.g., heparin, coumadin) that have non-specific mechanisms of action. These drugs can cause bleeding thus limiting their use. Anticoagulants that block early steps in the coagulation cascade, and are specific for either the intrinsic or extrinsic pathways (see FIG. 1), could have superior efficacy and safety profiles because thrombotic events are suppressed without inducing bleeding episodes.

Factor VIIa inhibitors from kunitz domain proteins


A wiring module includes a plurality of bus bars for connection to positive and negative electrode terminals of a plurality of electricity storage elements; a plurality of detection wires electrically connected the bus bars to detect a state of the electricity storage elements; a plurality of overcurrent protection elements connected between the plurality of bus bars and the plurality of detection wires; and an insulating protector in which the plurality of bus bars, the plurality of detection wires, and the plurality of overcurrent protection elements are disposed, wherein the insulating protector includes a bus bar arrangement portion in which the bus bars are disposed, and a plurality of extension portions which are extended to a region different from the bus bar arrangement portion and in which the overcurrent protection elements are disposed, and the plurality of extension portions are stacked in a plurality of levels.

Conventionally, an electricity storage module configured by arranging a plurality of electricity storage elements is mounted to a vehicle such as an electric car or a hybrid car. A wiring module that houses bus bars therein is mounted to the electricity storage module, and adjacent electrode terminals of the plurality of electricity storage elements are connected by the bus bars, and, thereby, the plurality of electricity storage elements are connected in series or parallel. In the battery wiring module of Patent Document 1, a voltage detection terminal is overlapped with each bus bar, and a detection wire connected to the voltage detection terminal is routed on a resin protector, and is connected to an external ECU.


A method (300) and system (200) for adding a connection identifier to an existing power saving class. The method can include the steps of—at a mobile unit (212) that is associated with at least one existing power saving class—generating (310) a type-length-value that specifies the identification of the existing power saving class, and integrating (312) the type-length-value into a dynamic service message request. The method can also include the step of transmitting (314) the dynamic service message request to a base station (210) such that the connection identifier will be automatically added to the existing power saving class without requiring deactivation or redefinition of the existing power saving class.

1. Field of the Invention
The subject matter herein concerns the addition of a connection identifier to an existing power saving class and more particularly, the addition of such an identifier without interrupting a sleep mode availability scheme.
2. Description of the Related Art
In current communication systems that operate in accordance with IEEE standard 802.16e, a mobile unit may be associated with one or more power saving classes (PSC), although each mobile unit is typically associated with a single PSC. A PSC defines sleep and listening windows for the mobile unit assigned to the PSC. The time period that exists when no listening window exists for all the PSCs to which a particular mobile unit is associated is referred to as an unavailability window, assuming that all the connections of the mobile unit are associated with a PSC. Thus, the unavailability window represents a time when the mobile unit is in a sleep period for all of its associated PSCs. During the unavailability window, a base station may not transmit to the mobile unit, which permits the mobile unit to power down certain components or perform other activities that do not require communication with the base station. The unavailability window is important in mobile communications because it permits the mobile unit to conserve battery power and allows for co-existence schemes with other radio technologies for avoiding interference.
As is known in the art, when a mobile unit is associated with a PSC, all the connection identifiers (CID) of that mobile unit are assigned to the PSC. Eventually, the mobile unit may wish to have a new service flow activated. Because the existing PSC will not contain the CID of the new service flow, this PSC will need to be deactivated, re-defined to include the new CID and then reactivated. This process is illustrated in the flow diagram of FIG. 1. In this drawing, signals originating from the left are sent from a mobile, while signals emanating from the right are transmitted from the serving base station. In addition, the shaded areas represent unavailability windows (see explanation above) and the lighter regions signify availability windows, or time periods where it may be possible for the mobile unit and the base station to exchange signals. In this scenario, it can be assumed that the mobile unit is associated with a single PSC and wishes to initiate a new service flow.
Initially, the mobile unit transmits a dynamic service addition request (DSA-REQ) to the base station during an availability window or interval. The base station responds by transmitting—during the next availability window—a dynamic service addition response (DSA-RSP) to the mobile unit, which leads to the activation of the new CID, assuming that the base station accepts the DSA-REQ. The mobile unit will then respond with a dynamic service addition acknowledgement (DSA-ACK).
As noted earlier, the existing PSC with which the mobile is currently associated will not contain the new CID. As such, the mobile unit will transmit a sleep request (SLP-REQ) to the base station, which will cause the base station to deactivate the current PSC and respond with a sleep response (SLP-RSP) to the mobile unit. The mobile unit will then transmit another SLP-REQ to the base station, which will define the parameters for the new PSC to accommodate the new CID. In response, the base station will activate the new PSC, which includes the new CID, and will transmit another SLP-RSP to the mobile unit. This SLP-RSP will also specify the start frame for the next sleeping period (i.e., unavailability window). As can be seen, the time before the mobile unit enters the next unavailability window is relatively lengthy. This additional time, however, is necessary because it allows the base station to re-transmit the SLP-RSP if there is a problem with its initial transmission and it permits the base station to perform synchronization procedures, like synchronizing all or some listening periods for multiple PSCs.
It can be clearly seen that there is a substantial amount of overhead and time involved when a mobile unit wishes to activate a new service flow. Because the current PSC must be deactivated, re-defined and reactivated, the mobile unit may not enter sleep mode during this process. Accordingly, this process negatively affects battery life. Moreover, the abundance of messages being exchanged leads to an inefficient use of network resources.

Method and system for adding a new connection identifier to an existing power save class


A low cost, compact, lightweight gambrel is disclosed. The gambrel can have a coupler, a cable, a spreader bar, and six swage sleeves. The coupler can be affixed to a limb of a tree or any other point that is semi rigid and to a loop of the gambrel formed by folding the cable over on to itself and threading the cable through an oval swage sleeve. During a swaging process, a hammer or a press can crimp the swage sleeve such that the sleeve secures the cable. Two holes can be fabricated proximate to the ends of a spreader bar and the cable can be inserted into another swage sleeve and into the holes of the spreader bar. Two more swage sleeves can be swaged on the cable on the bottom side of the spreader bar to hold the spreader bar in place. Two nooses can be formed on the ends of the cable. The nooses can be formed from loops at the end of cable by folding the cable and crimping swage sleeves to form the loop. The cable can then be placed through the loop to form a noose at each termination or end of the cable such loops can act as leg securing members.

Many individuals hunt wild game and prepare such game for consumption. Others raise small domestic animals and prepare such animals for personal consumption or dress the animals for purchase by others. Preparation of the carcass of a small animal for eating requires the game to be held properly. Properly holding of the carcass while skinning and butchering greatly simplifies the process and can prevent injury to the preparer. Different types of gambrels for dressing carcasses are available, however most of these holders are relatively large and made for dressing deer and the like. These holders are also relatively heavy and bulky and are not fit for carrying long distances and for dressing small animals. Accordingly, it would be desirable to have an improved system and method for holding small animal carcasses while they are dressed.


A paint station may include a frame with a table attached to it. A track may run along the length of the table. A bridge may be connected to the track and may move along the track. The bridge may extend across the width of the table. A painting component may be attached to the bridge and may move along the bridge. Therefore the painting component may run along two axes over the table. A computer may be connected to the paint station to direct the movement of the painting component along the two axes. A user may place a clothing apparel on the table and may input a command to paint a desired design on the clothing apparel.

The present invention relates to paint station and, more particularly, to a portable programmable paint station for adding designs to apparel.
Currently, it is desirable to acquire a shirt with a design as opposed to a shirt that is plain. The most common form of commercial T-shirt decoration is screen-printing. In screen-printing, a design is separated into individual colors. Plastisol or water based inks are applied to the shirt through mesh screens which limits the areas where ink is deposited. However, this is generally done in screen printing factories and the consumers are unable to develop and apply unique painted artwork to their personal clothing.
As can be seen, there is a need for a portable and programmable paint station.


An apparatus for detecting the passage of superposed sheets, e.g. currency notes, along a feed path (76) includes a mechanism which has a pair of cooperating rollers (12, 14) and which is arranged to generate an output voltage whose magnitude varies in response to the passage of an item (single or multiple sheet) between the rollers (12, 14). This output voltage is applied to an A/D converter whose outputs are sampled at regular intervals while an item is passing between the rollers (12, 14). A data processing means generates a first digital value representative of the sum of these outputs. From this digital value is subtracted a value representative of the sum of the outputs of the A/D converter over the corresponding part of the cycle of the rollers while no sheet is passing between them. A determination is thereby made as to whether or not said item comprises a single sheet.

This invention relates to an apparatus for detecting the passage of multiple superposed sheets along a feed path. The invention has application, for example, to an apparatus for detecting the passage of superposed currency notes in a cash dispensing mechanism of an automated teller machine (ATM).
In a cash dispensing mechanism, it is important to provide a simple and reliable means for detecting when a currency note has become superposed on another in a path of travel from a currency supply means to a note exit slot, since such superpositioning may produce an undesirable result such as the dispensing of an excessive amount of money. For convenience, two or more sheets or notes which have become disposed in a superposed relationship will hereinafter be referred to as a multiple sheet or a multiple note.
From EP-B-0344938 there is known an apparatus for detecting multiple sheets. This apparatus includes first and second cooperating rollers between which sheets pass as they are fed along a feed path, the first roller having a fixed axis of rotation, and the second roller being resiliently urged towards the first roller so as to enable it to be moved away from the first roller as a single or multiple sheet passes between the rollers. A voltage generating means associated with the second roller produces an output voltage which varies linearly with movement of the second roller towards or away from the first roller, and this output voltage is applied to an analog-to-digital (A/D) converter. A data processor is connected to the output of the A/D converter and is arranged to perform the steps of: sampling the value of said output voltage (as represented by the output of the AID converter) a predetermined number of times for an integral number (which may be one) of complete revolutions of one of the rollers when no sheet is passing between the rollers, the diameter of this roller being equal to or a multiple of the diameter of the other roller; storing a first digital value representative of the sum of the values sampled in the last-mentioned step; sampling the value of said output voltage said predetermined number of times for an integral number of complete revolutions of said one of the rollers when an item comprising a single or multiple sheet is passing between the rollers; storing a second digital value representative of the sum of the values sampled in the last-mentioned step; and subtracting the first digital value from the second digital value to produce a third digital value on the basis of which a determination is made as to whether a single or multiple sheet has passed between the rollers.
As mentioned in the above-identified document, an advantage of this apparatus is that by virtue of subtracting said first digital value (stored when no sheet is passing between the rollers) from said second digital value (so as to produce said third digital value) possible problems due to roller noise are eliminated. By roller noise is meant variations in the output of said voltage generator brought about by various factors such as bearing wear and tolerances, dirt on the rollers and roller eccentricity.
A limitation of the known apparatus referred to above is that the spacing between the leading edges of successive items fed to the apparatus must be at least as great as the circumference of the larger of the rollers (or at least as great as the circumference of each roller if they are of the same side). Another limitation is that any divert mechanism positioned in said feed path downstream of said rollers must be spaced from the nip of the rollers by a distance at least equal to said circumference.

Apparatus for detecting the passage of multiple superposed sheets along a feed path


A product development project assessment approach is provided which includes identifying multiple possible root causes of trouble for a product development project, identifying question sets related to the multiple possible root causes of trouble, and providing a computer-implemented tool to evaluate answers to the question sets and provide guidance regarding existence of one or more root causes of trouble for the product development project. The assessment approach further includes evaluating project management processes employed for the product development project by comparison thereof to identified, standard project management processes, and provide guidance regarding effectiveness of implementation of the project management processes employed. Product management work product is also evaluated as further evidence of the existence of one or more root causes of trouble or the effectiveness of implementation of the project management processes. The product development project can comprise a software or hardware development project.

Manual reviews of software application development projects are routinely performed to determine whether a project is on schedule, on budget and will deliver the promised function at the appropriate level of quality. Over the years, a number of researchers have shown that the failure rate of software development projects is exceptionally high and those studies also provide high level guidance on the typical or common root causes. The general categories of failure are known and are documented in many publications, including, for example, two publications authored by Steve McConnell entitled Code Complete, Microsoft Press (1993) and Rapid Development, Microsoft Press (1996), both of which are hereby incorporated herein by reference in their entirety. What is not as well understood is how to ascertain that a particular area of failure is present on a software development project. In addition, existing references do not include a logical approach to assess project management processes and their impact on the overall success or failure of a project.
A typical software project reviewer manually focuses on the project management system and/or dives deep into the technical aspects of the project. By operating purely at the project management system level, the reviewer may miss an underlying cause of corruption in the best practices by not applying a disciplined, logical approach to assessing the evidence that is generated by the effective use of project management best practices, i.e., by not assessing the artifacts that are produced. For example, a reviewer may look to determine that an issues management system is in place, but fail to check to determine if an issues log has the correct and adequate data to allow the issues management system to work. At the other end of the spectrum, i.e., at the technical end, a reviewer may focus on the technology or product dimensions of software delivery and fail to assess or understand the people and process impact on the ability of the team to deliver the required application.
By not having a logical, holistic, and end-to-end approach with consistent scoring and focused questions to identify areas of failure, the traditional review boils down to the application of the experience of the reviewer to the situation. If the reviewer has limited experience, then the validity of the project assessment suffers.
Thus, provided herein is a true end-to-end assessment approach which removes the product development project assessment from simply the reviewer's experience.

Method, system and program product for assessing a product development project employing a computer-implemented evaluation tool

International Business Machines Corporation


An apparatus for diagnosing an inflammatory condition relating to periodontitis made up of a probe with sensors for measuring temperature within a periodontal pocket. The apparatus further comprises a graduated scale for measuring the depth of the periodontal pocket. Also provided is equipment for recording the temperature difference between the bottom and the mouth of the periodontal pocket.

1. Field of the Invention
The present invention relates to an apparatus or diagnosing inflammatory conditions in connection with periodontitle, and the invention also involves a process for such diagnosis.
2. Description of Related Art
The loosening of teeth (periodontitis) is a bacterially caused inflammation in the attachment apparatus of the tooth (periodontium) which, if left untreated results in decomposition of the bone around the tooth (resorption) and of the tooth loosening its anchorage, the anchorage being ultimately lost. Periodontitis shall primarily be prevented by good oral hygiene but may also, after being established, be treated. This treatment will mainly be directed to interrupt the progress of the disease.
Practically all adults are to a greater or lesser degree subjected to the disease, and approximately 10% of the population in the industrialized world develop severe periodontitis resulting in partial or total loss of the teeth.
Periodontitis is initially a disease which to the patient lacks symptoms. However, the dentist can see early signs of an incipient disease development. The gum around the teeth become red, swollen and bleed easily, i.e. show signs of an inflammation. Simultaneously the pocket between tooth and gum will be subject to increased depth. In this pocket additional bacteria will accumulate and proliferate (plaque). Gradually the bacteria will calcify and calculus will form on the teeth. Synchronously with the formation of plaque the inflamation spreads in the attachment apparatus of the tooth and the bone surrounding the root of the tooth starts to decompose.
The methods available to the dentist to diagnose periodontitis is measuring the depth of the periodontal pocket around the tooth and registering the tendency for bleeding connection herewith. However, this does not give a full measure of the degree of inflamation in the attachment apparatus of the tooth. Above all these measures give little guidance for judging how the disease will develop. They rather reflect what has already taken place.
One of the greatest problem in the treatment of periodontitis is to be able to predict around what teeth the periodontitis activity will increase. It has been found that the loss of supporting tissue around the teeth in periodontitis fluctuates, i.e. periods of low disease activity succeed periods of high activity. Early signs of this can be seen in the degree of inflammation in the environment of the teeth. An incipient increase of the degree of inflammation should be treated as soon as possible in order to save as much as possible of the anchorage of the tooth. The traditional methods (depth of periodontal pocket and bleeding tendency) in order to estimate this condition are not reliable. A deep periodontal pocket does not necessarily mean that the periodontal process is active. A healing process may have started in the same manner a shallow periodontal pocket may not mean that the periodontal disease is inactive. Also a deep pocket has once been shallow and it is very important to be able to predict which periodontal pockets are subject to deepening.
The cardinal symptoms of a topical inflammatory condition is calor (temperature increase), dolor (pain), rubor (redness) and tumor (swelling). Out of these the redness (bleeding in the periodontal pocket) and the swelling (in combination with decomposition of alveolar bone, i.e. measuring depth of periodontal pocket) have traditionally been used to diagnose periodontitis. However, these symptoms of periodontitis are not reliable measures for estimating the activity of the disease. Furthermore, it is not possible to estimate bleeding quantitatively. These traditional methods, measuring of pocket depth and bleeding tendency, to judge the activity of the periodontal process often give misleading results, particularly in an early stage of an active period. A deep periodontal pocket which is bleeding does not always mean that the process is active.
The use of temperature as a measurement for the activity of periodontitis is based on the fact that an inflammatory process in view of increased flow of blood results in an early temperature increase (before the depth of the periodontal pocket has increased). However, in the mouth the temperature varies between different areas. The gum is warmer the deeper in the oral cavity the measurement le made (32.degree. C. to 37.degree. C.). An absolute temperature scale to estimate the degree of inflammation is thus not possible to define. However, the surface temperature in the opening of the periodontal pocket is not affected by a possible inflammation at the bottom the periodontal pocket.


In order to maximize the production of propylene when the external supply of ethylene is limited, the C4 cut from a hydrocarbon cracking process is first subjected to autometathesis prior to any isobutylene removal and without any ethylene addition. This favors the reactions which produce propylene and pentenes. The ethylene and propylene produced are then removed leaving a stream of the C4's and heavier components. The C5 and heavier components are then removed leaving a mixture of 1-butene, 2-butene, isobutylene, and iso- and normal butanes. The isobutylene is next removed preferably by a catalytic distillation hydroisomerization de-isobutyleneizer. The isobutylene-free C4 stream is then mixed with the product ethylene removed from the autometathesis product together with any fresh external ethylene needed and subjected to conventional metathesis producing additional propylene.

The present invention relates to the processing of a C3 to C6 hydrocarbon cut from a cracking process, such as steam or fluid catalytic cracking, primarily for conversion of C4 olefins to propylene via metathesis.
In typical olefin plants, there is a front-end demethanizer for the removal of methane and hydrogen followed by a deethanizer for the removal of ethane, ethylene and C2 acetylene. The bottoms from this deethanizer tower consist of a mixture of compounds ranging in carbon number from C3 to C6. This mixture is separated into different carbon numbers typically by fractionation.
The C3 cut, primarily propylene, is removed as product and is ultimately used for the production of polypropylene or for chemical synthesis such as propylene oxide, cumene, or acrylonitrile. The methyl acetylene and propadiene (MAPD) impurities must be removed either by fractionation or hydrogenation. Hydrogenation is preferred since some of these highly unsaturated C3 compounds end up as propylene thereby increasing the yield.
The C4 cut consisting of C4 acetylenes, butadiene, iso- and normal butenes, and iso- and normal butane can be processed in many ways. A typical steam cracker C4 cut contains the following components in weight %:
C4 acetylenestracebutadiene33%1-butene15%2-butene9%isobutylene30%iso- & normal butane13%Typically, the butadiene and C4 acetylenes are removed first. This can be accomplished by either hydrogenation or extraction. If extraction is employed, the remaining 1-butene and 2-butene remain essentially in the same ratio as that of the initial feedstock. If hydrogenation is employed, the initial product from butadiene hydrogenation is 1-butene. Subsequently, hydroisomerization occurs within the same reaction system changing the 1-butene to 2-butene. The extent of this reaction depends upon catalyst and reaction conditions within the hydrogenation system. However, it is common practice to limit the extent of hydroisomerization in order to avoid "over hydrogenation" and the production of butanes from butenes. This would represent a loss of butene feedstock for subsequent operations downstream. The butenes remaining in the mixture consist of normal olefins (1-butene, 2-butene) and iso-olefins (isobutylene). The balance of the mixture consists of both iso- and normal butanes from the original feed plus what was produced in the hydrogenation steps and any small quantity of unconverted or unrecovered butadiene.
The butenes have many uses. One such use is for the production of propylene via metathesis. Another is for the production of ethylene and hexene via metathesis. Conventional metathesis involves the reaction of normal butenes (both 1-butene and 2-butene) with ethylene. These reactions occur in the presence of a catalyst which consists of a group VIA or VII A metal oxide either supported or unsupported. Typical catalysts for metathesis are tungsten oxide supported on silica or rhenium oxide supported on alumina. Isobutylene (isobutene) is typically removed from the feedstock prior to the metathesis reaction step. The reaction of isobutylene with ethylene is non-productive and reaction with itself and/or other C4's is limited in the presence of excess ethylene. Non-productive reactions essentially occupy catalyst sites but produce no product. If allowed to remain in the feed to the metathesis unit, the concentration of this non-reactive species would build up creating capacity limitations. The reaction of 1-butene with ethylene is also non-productive. However, it is common to employ a double bond isomerization catalyst within the metathesis reactor to shift 1-butene to 2-butene and allow for continued reaction. Typical double bond isomerization catalysts include basic metal oxides (Group IIA) either supported or unsupported. Magnesium oxide or calcium oxide are examples of such double bond isomerization catalysts that are physically admixed with the metathesis catalyst. No equivalent co-catalyst exists for the skeletal isomerization of isobutylene to normal butene. In the case of the conventional metathesis system employing both a metathesis catalyst and a co-mixed double bond isomerization catalyst, the butadiene must be removed to a level of less than 500 ppm to avoid rapid fouling of the double bond isomerization catalyst. The metathesis catalyst itself can tolerate butadiene levels up to 10,000 ppm.
It is common to employ an isobutylene removal step prior to metathesis. Options include reacting it with methanol to produce methyl tertiary butyl ether (MTBE) or separating the isobutylene from the butenes by fractionation. In U.S. Pat. No. 6,358,482, the inventors teach the removal of isobutylene from the C4 mixture prior to metathesis. This scheme is further reflected in U.S. Pat. Nos. 6,075,173 and 5,898,091. In other prior art, in U.S. Pat. No. 6,580,009, Schwab et al teach a process for the production of propylene and hexene from a limited ethylene fraction. For molar ratios of ethylene to butenes (expressed as n-butenes) from 0.05 to 0.60, the inventors utilize a raffinate II stream as the C4 feedstock. A raffinate II stream is by definition a stream following isobutylene removal. Further, in claim 6 of the published application, they teach the steps of: (1) removal of butadiene; (2) removal of isobutylene by various means; (3) removal of the oxygenate impurities; (4) metathesis of the resultant raffinate II stream with 0.05 to 0.6 molar ratio of ethylene; (5) separation of products to form a lighter fraction of C2 and C3 stream and a heavier fraction C4 to C6 stream; (6) separating the lighter fraction into C2 and C3 product streams; (7) separating the heavier stream into a C4 stream, an intermediate C5 stream and a heavier C6+ stream; and (8) recycle of the unreacted C4 and at least partially the C5 normal olefins. This process specifically removes the isobutylene prior to metathesis.
In U.S. Pat. No. 6,271,430, Scwab et al disclose a two-step process for the production of propylene. The first step consists of reacting 1-butene and 2-butene in a raffinate II stream in an autometathesis reaction to form propylene and 2-pentene. The products are then separated in the second step. The third step reacts specifically the 2-pentene with ethylene to form propylene and 1-butene. This process utilizes the isobutylene free raffinate II stream. The pentenes recycled and reacted with ethylene are normal pentenes (2-pentene).
It is known that isobutylene removal from the C4 stream can also be accomplished by employing a combined catalytic distillation hydroisomerization deisobutyleneizer system (CD DIB system). This system will both remove the isobutylene and recover n-butenes at high efficiency by isomerizing the 1-butene to 2-butene with known isomerization catalysts and thus increase the volatility difference. This technology combines conventional fractionation for isobutylene removal with hydroisomerization within a catalytic distillation tower. In U.S. Pat. No. 5,087,780 to Arganbright, 2-butene is hydroisomerized to 1-butene as the fractionation occurs. This allows greater than equilibrium amounts of 1-butene to be formed as the mixture is separated. Similarly, 1-butene can be hydroisomerized to 2-butene in a catalytic distillation tower. In separating a C4 stream containing isobutylene, 1-butene, and 2-butene (plus paraffins), it is difficult to separate isobutylene from 1-butene since their boiling points are very close. By employing simultaneous hydroisomerization of the 1-butene to 2-butene with fractionation of isobutylene (CD DIB), isobutylene can be separated from the normal butenes at high efficiency.
The metathesis reaction described above is equimolar, i.e., one mol of ethylene reacts with 1 mol of 2-butene to produce 2 mols of propylene. However, commercially, in many cases, the quantity of ethylene available is limited with respect to the quantity of butenes available. In addition, the ethylene is an expensive feedstock and it is desired to limit the quantities of ethylene used. As the ratio of ethylene to butenes is decreased, there is a greater tendency for the butenes to react with themselves which reduces the overall selectivity to propylene.
The metathesis catalysts and the double bond isomerization catalysts are quite sensitive to poisons. Poisons include water, CO2, oxygenates (such as MTBE), sulfur compounds, nitrogen compounds, and heavy metals. It is common practice to employ guard beds upstream of the metathesis reaction system to insure the removal of these poisons. It does not matter if these guard beds are directly before the metathesis reaction system or further upstream as long as the poisons are removed and no new poisons are subsequently introduced.
Metathesis reactions are very sensitive to the location of the olefin double bond and the stereo-structure of the individual molecules. A pair of olefins adsorb on the surface and exchange double bond positions with the carbon groups on either sides of the double bonds. Metathesis reactions can be classified as productive, half productive or non-productive. As described above, non-productive reactions result in essentially no reaction taking place. When the double bonds shift with metathesis reaction, the new molecules are the same as the originally adsorbed molecules thus no productive reaction occurs. This is typical for reactions between symmetric olefins or reactions between ethylene and alpha olefins. If fully productive reactions occur, new products are generated no matter which orientation the molecules occupy the sites. The reaction between ethylene and 2-butene to form two propylene molecules is a fully productive reaction. Half productive reactions are sterically inhibited. If the pair of olefins adsorb in one orientation, when the double bonds shift new products are formed. Alternately if they adsorb in a different steric configuration, when the bonds shift, the identical olefins are formed and thus no new products are formed. The various metathesis reactions proceed at different rates (a fully productive reaction is usually faster than a half productive reaction) and with different weight selectivities to propylene. Table A summarizes the reactions between ethylene and various butenes and the reactions between the butenes themselves.
The reactions listed represent the base reaction with ethylene (reaction 1, 4 and 5) as well as the reactions between the various C4 olefins. It is especially important to make a distinction between the selectivity to propylene from total C4 olefins (including isobutylene) and the selectivity to propylene from the normal C4 olefins involved in the reaction. The reaction of isobutylene with 2-butene (reaction 6) produces propylene and a branched C5 molecule. For this reaction, propylene is produced at 37.5 weight % selectivity from total C4's (similar to reaction 2) but at a 75 weight % selectivity from normal C4's (2-butene). For the purposes of definitions, conventional metathesis is defined as the reaction of the C4 olefin stream with ethylene. However, the C4 stream can also react without the presence of ethylene as a feedstock. This reaction is called auto or self metathesis. In this case, reactions 2,3 6, and 7 are the only possible reactions and will occur at rates dependent upon the feedstock composition.
TABLE AWt %Wt %selectivityselectivity(C3H6 fromC3H6 fromReactionRatetotal C4's)(n-C4's)12-butene + ethylene → 2Fast100100propylene (conventionalmetathesis) (fully productive)21-butene + 2-butene →Fast37.537.5propylene + 2-pentene(fully productive)31-butene + 1-butene →Slow00ethylene + 3-hexene(half productive)4isobutylene + ethylene →No Rknno reaction51-butene + ethylene →No Rknno reaction6isobutylene + 2-butene →Fast37.575propylene + 2-Me 2-butene(fully productive)7isobutylene + 1-butene →Slow00ethylene + 2-me 2-pentene(half productive)It is common practice in conventional metathesis to maximize reaction 1 to produce propylene. This will maximize the selectivity to propylene. As such, excess ethylene is used to reduce the extent of the reactions of butenes with themselves (reactions 2, 3, 6, and 7). The theoretical ratio is 1/1 molar or 0.5 weight ratio of ethylene to n-butenes but it is common in conventional metathesis to employ significantly greater ratios, typically, 1.3 or larger molar ratio to minimize reactions 2, 3, 6 and 7. Under conditions of excess ethylene, and due to the fact that both isobutylene and 1-butene do not react with ethylene (see reactions 4 and 5), two process sequences are employed. First, the isobutylene is removed prior to metathesis. If isobutylene is not removed, it will build up as the n-butenes are recycled to achieve high yield. Second, 1-butene is isomerized to 2-butene by including a double bond isomerization catalyst such as magnesium oxide admixed with the metathesis catalyst. Note that this catalyst will not cause skeletal isomerization (isobutylene to normal butylenes) but only shift the double bond from the 1 position to the 2 position. Thus by operating with excess ethylene, eliminating isobutylene from the metathesis feed prior to reaction, and employing a double bond isomerization catalyst, reaction 1 is maximized.
When there is limited or no fresh ethylene (or excess butylenes for the ethylene available), there are currently two options available for propylene production. In these cases, the current technology will first remove the isobutylene and then process the normal butenes with whatever ethylene is available. The entire n-butenes only mixture is subjected to metathesis with the available ethylene. Ultimately, if there is no fresh ethylene available, the C4's react with themselves (auto metathesis). Under low ethylene conditions, reactions 2, 3, 6 and 7 will occur, all leading to a lower propylene selectivity (37.5% or lower versus 100% for reaction 1). The lower selectivity results in lower propylene production. Note that reactions 6 and 7 will be minimized as a result of the removal of isobutylene (to low levels but not necessarily zero). Alternately, the molar flows of ethylene and butenes can be matched by limiting the flow of butenes to produce conditions where there is a high selectivity of the normal butenes to propylene via reaction 1. By limiting the flow of n-butenes to match ethylene, the production of propylene is limited by the reduced butenes flow.
Pentenes and some hexenes are formed to some extent in the conventional metathesis case with low ethylene. The volume of these components will depend upon the ethylene/n-butenes ratio with a lower ratio producing more C5 and C6 components. In the conventional prior art case where isobutylene is removed before any metathesis, these C5 and C6 olefins are normal olefins since no skeletal isomerization occurs. It is possible to recycle these olefins back to the metathesis step where for example the reaction with ethylene and 2-pentene will occur yielding propylene and 1-butene. The 1-butene is recovered and recycled. Note however, with limited ethylene, reaction 1 can occur only to the limit of the ethylene availability. Ultimately these non-selective byproducts, pentenes and hexenes, must be purged from the system. While the presence of these olefins impacts the required size of the equipment, they do not represent losses of potential propylene production.

Processing C4 olefin streams for the maximum production of propylene


A tonneau board used in a luggage space and movable according to opening and closing of a back door of a vehicle is provided. The tonneau board includes a rear board, a hinge portion, a front board, and an elongated connecting member. The rear board is disposed in front of the back door and includes a connect portion in a vehicular front portion thereof. The front board is in front of the rear board and connected to the rear board via the hinge portion to be pivotable around the hinge portion. The connecting member has flexibility and is configured to connect the rear board and the back door and includes a loop connected to the front portion of the rear board via the connect portion.

A tonneau board to be disposed in a luggage space of a vehicle has been known. Such a tonneau board (a rear package tray) includes two boards that are arranged in a front-rear direction of the vehicle. The two boards are connected via a hinge portion so that the two boards pivot relative to each other around the hinge portion.
One of the boards arranged on the rear of the vehicle is connected to a back door of the vehicle via connecting members (suspending ropes). Specifically, a vehicular rear edge of the board on the rear side is connected to the back door. When the back door is opened, the board on the rear side of the tonneau board is lifted up.
In the above configuration, when the back door is opened, the board on the rear side pivots around the hinge portion relative to the board on the front side and is lifted upward. Although the board on the rear side is lifted up, the board on the front side is not effectively lifted up. In this configuration, it is hard for a person to see the luggage placed under the board on the front side.
The present technology is accomplished in view of the above situations and an objective of the present technology is to provide a tonneau board including at least two boards each of which is lifted when a back door is opened.


An internal combustion engine includes a piston dividing a cylinder into first and second variable volume chambers on either side thereof. One chamber admits and compresses air which is delivered to another chamber for combustion. The other chamber admits combustion gasses, causing the piston to translate in the cylinder. In one embodiment, combustion of fuel occurs in a combustion chamber separate from the first and second variable volume chambers. In one embodiment, the translation of the piston effects movement of a connecting rod connected to an output shaft. In another embodiment, the piston is mounted on an output shaft and translation of the piston causes the piston to rotate, thus effecting rotation of the output shaft.

In accordance with the laws of thermodynamics, it is desirable to provide an engine which maximizes pressure and temperature during combustion, as such results in the most efficient conversion of energy. In addition, in accordance with the laws of physics, the power to weight ratio of an engine increases as the speed of engine operation increases.
Unfortunately, a variety of secondary effects make difficult the achievement of an engine which achieves these objectives. As engine speed increases, so do the inertial forces and the stresses placed upon moving parts in the engine. At high speeds, the failure rate of these parts increases. Increasing the size of these parts to increase their strength has limited benefits, as such further increases the inertial forces and the total weight of the engine.
In some instances, current engine designs also do not permit ready solutions to these problems. For a number of reasons, traditional piston rods are much longer than the distance of the entire piston stroke. One advantage arising from a longer piston rods is such permits a longer piston stroke, and thus a higher compression ratio. The longer piston rod also provides greater clearance between the piston and crankshaft at bottom dead center. On the other hand, the longer piston rod is subject to high inertial forces.
A problem with raising engine temperatures and pressures is that the life of parts subjected to these high heat and pressures in the engine are reduced. In order to reduced the detrimental effects of the high heat, today's engines employ cooling systems. The cooling systems, however, serve to reduce the efficiency of the system.
Another problem with an engine operating at high speed is that the time for combustion is very short. To accommodate combustion time, combustion may be initiated before the piston is at top dead center. Combustion forces generated as the piston moves upwardly to top dead center act against the direction of the piston, contributing to a lower energy level of the engine. On the other hand, if combustion is not initiated until the piston is at top dead center, then total optimum combustion time is very short. As a result, the generated combustion force is limited, and so is the power output of the engine in relation to provided fuel.
Another disadvantage of a short combustion time is that certain less combustible alternative fuels are not usable in these engines. Simply, the combustion time is so short that slower combusting fuels do not sufficiently combust to generate efficient engine power. A problem with existing engines is that the optimal combustion time is so short, that it is detrimental to raise the speed of the engine because optimal combustion time is further shortened. This problem thus prevents achievement of an engine with otherwise higher efficiency by operation at higher speeds.
Two-cycle internal combustion engines have an advantage over four-cycle internal combustion engines in that an entire piston cycle is not lost without producing force. On the other hand, combustion effects are reduced due to incomplete scavenging: not all of the exhaust gasses are exhausted before combustion initiates, and insufficient incoming air is provided for complete combustion of the fuel.
One detrimental side effect of this incomplete combustion of fuel is the exhausting of unburned fuel and undesirable gasses. Due to the emission problems associated with two-cycle engines, in some instances U.S. laws prevent the operation of two-cycle engines.
Another problem with existing engines is that they are not suited to miniaturization and for use not only as prime movers, but as compressors and pumps. In particular, the current design of internal combustion engines, including by reason of having so many moving parts, is not suited to such adaptation.
An engine which is capable of exploiting the advantages of high pressures of combustion, high temperatures of combustion, and high engine speed is desired, as is an engine having minimal moving parts, such as one having no crankshaft or connecting rods, which is thus suited for miniaturization.

This patent is subject to a terminal disclaimer.

Multi-chamber internal combustion engine


A digital compensation circuit for calibrating a sensor is described. The compensator circuit includes a serial communication circuit for receiving data relating to a plurality of parameters and a compensation circuit coupled to serial communication circuit for providing piece-wise linear compensation of a temperature coefficient (TC). In one embodiment, the compensation circuit further includes a detector for detecting a threshold for a digital temperature and providing an output and a plurality of registers coupled to the detector and the serial communication circuit, a first plurality of registers for providing a first value if the digital temperature is above the threshold, a second of the plurality of registers for providing a second value if the digital temperature is below the threshold. The compensation circuit further includes a selector coupled to the detector and the plurality of registers for selecting one of the first and second of the plurality of registers dependent upon the output of the detector for providing piece-wise linear compensation of a temperature coefficient.

Piezoresistive and capacitive sensors are being used in increasingly higher accuracy applications for sensing various changes in pressure and the like in a variety of environments. Because the output of these sensors typically varies over temperature, the sensors require compensation and calibration in order to achieve the accuracy and temperature stability requirements of these applications. The calibration of sensors typically requires the adjustment of four parameters to achieve optimum output performance over temperature--offset, offset temperature coefficient (OTC), signal gain, and gain temperature coefficient (GTC).
In general the transfer function of a sensor is given by: EQU Vsens=Offset.sub.0 .multidot.(1+.alpha..sub.1 .multidot.T+.alpha..sub.2 .multidot.T.sup.2 + . . . +.alpha..sub.n .multidot.T.sup.n)+S.sub.0 .multidot.(1+.beta..sub.1 .multidot.T+.beta..sub.2 .multidot.T.sup.2 + . . . +.beta..sub.n .multidot.T.sup.n).multidot.Q Equation 1
where:
Vsens is the sensor output voltage PA1 Offset.sub.0 is the sensor offset (output with zero excitation) at a reference temperature (e.g. 25.degree. C.) PA1 .alpha..sub.1 is the first order temperature coefficient of the sensor offset PA1 .alpha..sub.2 is the second order temperature coefficient of the sensor offset PA1 .alpha..sub.n is the n.sup.th order temperature coefficient of the sensor offset PA1 T is the temperature difference from the reference temperature PA1 S.sub.0 is the sensor sensitivity or span at the reference temperature (e.g. 25.degree. C.) PA1 .beta..sub.1 is the first order temperature coefficient of the sensor sensitivity PA1 .beta..sub.2 is the second order temperature coefficient of the sensor sensitivity PA1 .beta..sub.n is the n.sup.th order temperature coefficient of the sensor sensitivity PA1 Q is the physical parameter being sensed (e.g. pressure, acceleration, etc.) PA1 Vout is the calibrated sensor output voltage (output of conditioning circuit) PA1 Gain.sub.0 is the gain of the compensating amplifier at the reference temperature PA1 Voff is the offset added by the conditioning circuit PA1 Votc.multidot.T is the temperature dependent component of the offset added by the conditioning circuit PA1 .delta. is the temperature dependent component of the gain of the compensating amplifier which counteracts the temperature dependent component of the sensor sensitivity PA1 Voff=-Offset.sub.0 PA1 Votc=-Offset.sub.0 .multidot..alpha..sub.1 PA1 and .delta.=-.beta..sub.1
For most sensor applications, all but the first order terms can be ignored so that Equation 1 becomes: EQU Vsens=Offset.sub.0 .multidot.(1+.alpha..multidot.T)+S.sub.0 .multidot.(1+.beta..multidot.T).multidot.Q Equation 2
However, for high accuracy sensor applications, the second order terms are usually included so that Equation 1 becomes: EQU Vsens=Offset.sub.0 .multidot.(1+.alpha..sub.1 .multidot.T+.alpha..sub.2 .multidot.T.sup.2)+S.sub.0 .multidot.(1+.beta..sub.1 .multidot.T+.beta..sub.2 .multidot.T.sup.2).multidot.Q Equation 3
To compensate this signal, a signal conditioning circuit is required which must subtract out the offset terms and provide amplification which varies with temperature to counteract the effect of the sensor span (TC). Traditionally, the signal conditioning has been done with opamps and laser trimmed resistors. However, this type of signal conditioning circuit is usually limited to providing first order correction of the temperature dependent terms. In addition this method is expensive as it requires the use of a laser and the solution is typically not monolithic (on a single integrated circuit) as the opamps and resistors are usually built on separate substrates.
An embodiment of a conventional digital compensation circuit 100 is shown in FIG. 1. In this embodiment, the differential signal from the sensor 5' is fed into an amplifier 102 which may have a gain of 1 or greater depending on the application. The output of this amplifier is fed into another amplifier stage 104 whose gain is controlled by the contents of a gain register 106. In addition, the offset and offset TC terms are added at summation point 114 in this stage using DACs 108, 110, 112 controlled by digital parameters. The compensation of the sensor sensitivity TC is done in the third stage 116 after the offset, offset TC and gain compensation. The third stage 116 may also have a gain of 1 or greater depending on the application. The final stage is an output buffer 111.
In this circuit, the temperature, T, is sensed using an on-chip proportional to absolute temperature (PTAT) circuit 122. The analog signal representing T is digitized using an analog-to-digital converter 124. The digital word representing T is then used to control two DACs 110 and 120, one for the offset TC compensation and the other for the gain TC compensation Digital information representing the values of the compensation terms, is serially fed into an on-chip control unit 125. The individual bits are decoded and sent to the various DACs 108, 110, 112, and 118. Once the correct binary code has been selected to center the sensor characteristic in the specified range, the code is stored using a digital storage method such as zener-zap, EEPROM or fuse link. The transfer function of this circuit 100 is given by Equation 4. EQU Vout=(Vsens+Voff+Votc.multidot.T).multidot.Gain.sub.0 .multidot.(1+.delta..multidot.T) Equation 4
Combining equations 3 and 4 gives: EQU Vout=S.sub.0 .multidot.Q.multidot.(1+.beta..sub.1 .multidot.T+.beta..sub.2 .multidot.T.sup.C)+Offset.sub.0 .multidot.(1+.alpha..sub.1 .multidot.T+.alpha..sub.2 .multidot.T.sup.2).multidot.+Voff+Votc.multidot.T.multidot.!.multidot.Gain .sub.0 .multidot.(1+.delta..multidot.T) Equation 5
The calibration of the sensor involves making measurements of Vout at various values of Q and various temperatures and thereby deducing the values of Voff, Votc, Gain.sub.0 and .delta. to minimize the error between Vout and the ideal sensor characteristic. Ideally the Voff, and Gain.sub.0 terms would be found first using measurements at the initial calibration temperature at minimum and maximum Q. The temperature dependent terms would then be found by an additional set of measurements at high (or low) temperature.
By setting:
equation 5 becomes: EQU Vout=S.sub.0 .multidot.Q.multidot.Gain.sub.0 .multidot.1+T.sup.2 .multidot.(.beta..sub.2 +.delta..multidot..beta..sub.1).sub.2 +T.sup.3 .multidot..delta..multidot..beta..sub.2 !+Offset.sub.0 .multidot..alpha..sub.2 .multidot.Gain.sub.0 .multidot.(1+.delta..multidot.T).multidot.T.sup.2 Equation 6
The desired term is simply S.sub.0 .multidot.Q.multidot.Gain.sub.0. All the other terms arise because this circuit only corrects for linear variations of the sensor offset and sensitivity with temperature. In high accuracy applications these extra terms may limit the usability of the sensor since it may be impossible to calibrate the sensor within the desired specification.
Accordingly, what is needed is a system and method to allow for more accurate calibration of sensors. The system and method should be easy to implement and cost effective. The present invention addresses such a need.

System and method for high accuracy calibration of a sensor for offset and sensitivity variation with temperature


Ion accelerating devices including connection mechanisms with integrated shielding electrode and related methods are disclosed. According to an embodiment, an ion accelerating device of an ion implantation system comprises: a first element; a first connection system within the first element, the first connection system including a first connector and a first encapsulated shielding electrode around the first connector; and a second connection system within a second element other than the first element, the second connection system being coupled to the first connector; wherein the first encapsulated shielding electrode includes a first shielding portion adjacent to a first interface surface of the first element where the second connection system interfaces with the first element, in a cross-sectional view, the first shielding portion being substantially U-shaped.

1. Technical Field
The present disclosure relates generally to ion implantation, and more particularly, to an ion accelerating device including connection mechanisms with an integrated shielding electrode and related methods.
2. Related Art
Ion implantation is a standard technique for introducing conductivity altering impurities into, or doping, semiconductor wafers. A typical ion implantation process uses an energetic ion beam to introduce impurities (ions) into semiconductor wafers. During ion implantation, a source feed material is energized to generate an ion beam, and the generated ion beam needs to be accelerated by an acceleration column. An acceleration column may be required to accelerate an ion beam at, for example, 670 kV. Preferably, the acceleration is accomplished by the ion beam passing through seven lenses internal to the acceleration column with voltages graded across the lenses due to ion optics requirements.
Active or passive grading schemes are used to control/produce the graded voltages, which require electrical and mechanical connections to the lenses through, e.g., a respective bushing unit. The connection point or termination point, if not protected, is usually a high electrical stress region and can be a weakest point of the accelerating column, which may lead to high voltage failures. As shown in FIG. 6, when a grading circuit board 312 is connected to a bushing unit 314 through a connector 316, at connection point 318, an interface is formed between solid insulation material of bushing unit 314 and/or grading circuit board 312, gas environment 322 that includes air, SF6, or/and other gases, and metal material of connectors 316 (referred to as triple junction). The equal potential line (iso-potential line) 320 is also adjacent to connection point 318 due to the metal material of connector 316. The high electrical stress on connection point 318, defined as (ΔV)/d where ΔV indicates the difference in electrical potentials and d indicates a distance, may cause an electrical discharge. For example, air beaks down at the electrical stress of 75 kV per inch. This electrical stress may exist between the two connectors 316, between connection point 318 and a ground (not shown) and/or between connection points 318 of two adjacent bushing units 314. The electrical discharge may cause electrical failures at connection point 318.

Ion acceleration column connection mechanism with integrated shielding electrode and related methods

Varian Semiconductor Equipment Associates, Inc.


A two-handed pliers-type fencing tool having a circular jaw pin which provides a fulcrum point allowing the user to stretch wire is disclosed. The fencing tool further provides an upper arcuate surface terminating in double tines for removing staples and a wire-gripping pincer, a hammer pad, and cutting notches near the pivotal point of the scissors-type tool. Methods for repairing of fence and stretching of wire are also disclosed.

1. Field of the Invention
The invention relates to a fencing tool and in particular to a fencing tool which can be used for stretching wire.
2. Discussion of the Technical Problems
maintaining fence and in particular barbed wire is a never ending job. Livestock, wildlife and the elements are continually working to loosen and break fence. Many farmers and ranchers find that it is necessary to continually inspect and repair their existing fences, whether by motorized vehicle, by walking, or on horseback. In order to adequately repair fence, it is often necessary to add an additional length of wire and then stretch the wire to insure that it is taut. The conventional manner of stretching fence wire is to use a fence stretcher. Conventional fence stretchers use mechanical advantage by employing ratchets, pulleys, and/or ropes or the like. Conventional fence stretchers are heavy and cumbersome to carry, set up, and use.
While one is engaged in repairing fence, it is necessary to have a pair of pliers or other tool which will allow one to remove staples, remove clips from metal posts, crimp wire, cut wire, and pound staples and nails. In the past, it has been a custom to use conventional fencing pliers which allow one to crimp wire and pound staples but do not allow person to adequately pull staples or stretch wire when needed.
The ideal fencing tool would provide the necessary gripping, pounding, and pulling functions as well as incorporating the means for stretching wire to facilitate total fence repair. Such a combination tool should be convenient to carry so that additional tools are not needed when walking along a fence or while riding horseback.
No known examples exist of a combination tool which will stretch wire, pound staples, crimp wire, place or remove clips on steel posts, and still be light enough to be placed into a holster or buckles onto a belt. There is no known single tool that will perform those functions so that one can repair a fence without the necessity of carrying a fence stretcher and assorted other tools.
Other prior art fencing tools and pliers having various arrangements in combinations are known. Examples of such tools include U.S. Pat. No. 1,382,109 to Matsler issued Jun. 21, 921, U.S. Pat. No. 1,532,147 to MacPherson issued Apr. 7, 1925, U.S. Pat. No. 2,462,250 to Andrews issued Feb. 22, 1949, U.S. Pat. No. 885,816 to Weyeneth issued Apr. 28, 1908, U.S. Pat. No. 1,495,028 to Mitchell issued May 20, 1924, U.S. Pat. No. 1,644,352 to Perrin issued Oct. 4, 1927, U.S. Pat. No. 1,675,476 to West issued Jul. 3, 1928, U.S. Pat. No. 1,949,335 to Settles issued Feb. 27, 1934, U.S. Pat. No. 2,313,530 to Feigion issued Mar. 9, 1943, U.S. Pat. No. 2,681,203 to Seger issued Jun. 15, 1954, and U.S. Pat. No. 2,967,303 issued Jan. 10, 1961.
Very few devices in the known art relate to combination fencing tool pliers for pulling staples, driving staples, crimping wire, and none known are directed to a combination fencing tool which will also grip the wire and stretch it across a fulcrum bar.
Accordingly, a need exists for a fencing plier that would provide a safe, convenient balanced tool that allows one to repair fence without the use of any other tool. The tool should not only crimp wire, drive and pull staples, but also stretch the wire without the use of additional tools. A fencing tool of that type would provide a fulcrum stretching mechanical advantage and yet the tool would be simple in design, easy to maintain, and would accommodate different types of wire, staples, and varying fencing conditions.
The device should be uncomplicated in design, easily carried by slipping it through a belt or wearing on a holster. It should be lightweight, not subject to damage by proper use, and simple to manufacture. The instant invention is directed to all of these needs as well as to others as explains in the following summary.
It is a feature of the invention to provide a fencing tool.
It is another feature of the instant invention to provide a fencing tool having balance and mechanical advantage by having sufficiently long handles.
It is another feature of the instant invention to provide a fencing tool having a hammer pad, shears for cutting wire, plier-jaw pincers, dual-pronged staple puller, wire-holding gripping surface, and a fulcrum bar for stretching wire.
These and other features and objects are attained according to the instant invention by providing a fencing tool having two parts pivotally joined in a scissor-like fashion with elongate handles. A hammer pad is provided on the handle side of the pivot and a wire-gripping pincer is provided at the head of the tool along with an acruate upper surface having a pair of tines useful for extracting staples by straddling a wire. A curved fulcrum bar is attached to one side of the working head and is telescopically inserted in an aperture in the opposite working head. The fulcrum bar is spaced from the pivot point and the pincer point so that wire may be inserted for stretching. On the handle side of the tool, a wire-gripping surface is provided so that the wire may be gripped and stretched over the fulcrum bar using the mechanical advantage of the long handles. Shearing notches are provided on either side of the pivot.


A variable geometry turbine in which a turbine wheel is mounted to rotate about a pre-determined axis within a housing. A sidewall is displaceable relative to the housing to control the width of a gas flow passage defined adjacent the wheel between the first surface defined by the sidewall and the second surface defined by the housing. The sidewall is mounted in the sidewall cavity within the housing on axially displaceable rods extending parallel to the rotation axis of the wheel. A yoke is pivotally supported within the housing and defines arms each of which extends into engagement with a respective sidewall support rod. The yoke is pivoted relative to the housing to control the position of the sidewall relative to the housing. The yoke is located within a yoke chamber defined by the housing, and lubricant is delivered to the yoke chamber to lubricate both the bearing upon which the yoke is pivotally mounted in the housing and surfaces which interengage the yoke and the sidewall support rods. The yoke chamber is spaced from sealed against communication with the sidewall cavity.

U.S. Pat. No. 4,973,223 describes a known variable geometry turbine in which a turbine wheel is mounted to rotate about a pre-determined axis within a housing. A sidewall is displaceable relative to a surface defined by the housing in order to control the width of gas flow passage defined adjacent the wheel between the sidewall and that surface. The sidewall is supported on rods extending parallel to the wheel rotation axis, and the rods are axially displaced relative to the housing so as to control the position adopted by the sidewall.
The rods are displaced by a pneumatic actuator mounted on the outside of the housing, the pneumatic actuator driving a piston which is displaceable parallel to the turbine axis. The actuator piston is coupled to the sidewall by a yoke pivotally supported on a bracket mounted on the housing, the yoke defining two spaced apart arms which extend on opposite sides of the turbine axis to engage portions of the support rods extending outside the housing. The end of each arm is received in a slot in a respective sidewall support rod. Displacement of the actuator piston causes the yoke to pivot and to drive the sidewall in the axial direction as a result of the interengagement between the yoke arms and the sidewall support rods.
In the known variable geometry turbine, the yoke pivot is located in the hostile environment outside the housing and cannot be readily lubricated. The engagement of the yoke arms with the rods is of a sliding nature and, although it is known to incorporate wear resistant relatively sliding surfaces made from for example ceramics, those surfaces cannot readily be lubricated. Accordingly wear can be a problem with the known assembly.
U.S. Pat. No. 5,522,697 describes an alternative yoke assembly to that described in U.S. Pat. No. 4,973,223. In that alternative assembly, the sidewall support rods are engaged by a yoke pivotally mounted within the housing on a shaft that extends outside the housing. An external actuator controls the rotation of the shaft and thus displacement of the yoke which engages in slots in the sidewall support rods. The yoke is mounted in a cavity immediately behind the sidewall.
With the arrangement of U.S. Pat. No. 5,522,697, the yoke is relatively compact and the yoke pivot and support rod engagement surfaces are located within the housing and therefore isolated from the hostile environment outside the housing. Unfortunately however the yoke is exposed to the conditions prevailing immediately behind the sidewall and it is not possible to lubricate the yoke given those conditions. As a result wear can still be a problem.


A phototherapy system and method for automatically replacing a failed light source with a new light source once a failure of a first light source is detected. This system permits the new light source to assume a coaxially aligned position with the proximal end portion of a light transmission medium in place of the failed light source without any manual input by the user. In addition, an improved coupling system is provided for coupling the light transmission medium to the illumination device housing the light sources. The coupling system prevents pull out of the light transmission medium from the illumination device over nearly all rotational angles of the proximal end of the light transmission medium relative to the housing, and over only a relatively small range of angles will some degree of pull out force enable the light transmission medium to be decoupled from the illumination device.

1. Field of the Invention
The present invention pertains to a phototherapy system and method for providing a therapeutic light treatment to a patient, and, in particular, to a phototherapy system and method in which a bulb switching mechanism automatically replaces a failed bulb with a new bulb, and to a phototherapy system having an improved fiber optic cable coupling system.
2. Description of the Related Art
Phototherapy devices that generate radiant energy, typically a visible light having a particular wavelength, and that transmit the energy to a surface of a patient are known. In one type of phototherapy device, light from a halogen bulb is transmitted to the surface of the patient to treat jaundice. An example of such a conventional phototherapy device is the Wallaby(copyright) II phototherapy system distributed by Respironics Inc. of Pittsburgh, Pa.
Such conventional phototherapy devices typically include a source of illumination and a fiber optic cable having a proximal end coupled to the source of illumination for transmitting the light to the patient. A fiber optic panel is located at the distal end of the fiber optic cable to provide a blanket of light that can be positioned next to the patient""s skin. A concern with such conventional devices is maximizing the lifetime of the device before the bulb or bulbs that produce the light have to be replaced.
This problem is addressed in conventional systems by providing two bulbs in the illumination device. If the first bulb fails, e.g., bums out, a manually actuated button is provided on the exterior housing of the illumination device. Depressing the button causes the second lamp, which is provided on a rotating carousel with the first lamp, to move into an operating position in place of the first lamp for illuminating the proximal end of the fiber optic cable. Thus, the user need not replace the bulbs until both bulbs have failed, thereby increasing the amount of time the phototherapy system can be used between bulb replacements.
This conventional approach, however, has several disadvantages. If the first bulb fails in the middle of the night, for example, while the patient is asleep, the patient or caregiver may not be aware of the failure until the following morning, thereby depriving the patient of the phototherapy during the night subsequent to the bulb failure. This problem is addressed in conventional device by providing an audible warning that is actuated upon bulb failure. Such warning devices, however, are a great cause for consternation, especially in situations where the user is unfamiliar with the purpose of the warning and/or is already apprehensive about the health of the person being treated by the phototherapy.
In addition, the conventional approach for dealing with bulb failures requires that the user manually cause the second bulb to move into position to replace the first bulb by actuating the bulb replacement button. Some patients may be unfamiliar with this procedure or have difficulty remembering to do so when the bulb replacement warning sounds. Also, some patients may have difficulty in being trained to take this necessary action once a bulb failure occurs. In addition, some patients may be physically unable to actuate the bulb replacement button, which requires depressing the bulb replacement button with a moderate amount of force sufficient to rotate the lamp carousel.
Furthermore, once the bulb replacement button has been actuated, the user cannot return the rotating carousel to the original position. Instead, the device must be delivered to a repair center where a trained technician replaces the bulbs and returns the carousel to the original position. As a result, if the user accidentally or prematurely causes the carousel to rotate, for example, by inadvertently depressing the bulb replacement button, the useful life of that device is effectively reduced. Yet another disadvantage with conventional phototherapy devices is that the mechanical rotation of the lamp carousel typically moves the lamps very rapidly and has an abrupt stop once the carousel has been rotated. This rapid movement and abrupt stop can cause mechanical shock to the filaments in the bulbs, thereby reducing lamp life.
Conventional phototherapy devices also include a system for coupling the proximal end of the fiber optic cable to the illumination device. The proximal end of the fiber optic cable receives light from the light source in the illumination device and transmits the therapeutic light to the distal end of the fiber optic cable for transmission to the patient""s skin. The coupling system attaches the proximal end of the fiber optic cable to the illumination device so that the proximal end surface of the fiber optic bundle is situated a fixed distance from the light source to receive light from the light source. Conventional coupling systems also permit the fiber optic cable to rotate relative to the illumination device while maintaining the proximal end in an engaged relation with the illumination device a fixed distance from the light source. Two techniques are known for such coupling systems.
In a first technique, a channel is provided on the exterior surface of the illumination device to receive the proximal end of the fiber optic cable. A 360xc2x0 slot is provided in the wall of the channel and a key slot is provided in the 12:00 position of the channel to provide access to the 360xc2x0 slot. The key slot and the 360xc2x0 slot are arranged such that during insertion of the proximal end of the fiber optic cable, a fixed protrusion provided on the proximal end of the fiber optic cable passes through the key slot into the 360xc2x0 slot. During insertion, the protrusion must be located at the 12:00 position so that the protrusion passes through the key slot. Because there is nothing blocking the key slot, very little force is needed to insert the cable into the illumination device. The proximal end of the cable is then rotated in the 360xc2x0 slot to move the protrusion on the cable away from the key slot. Engagement of the fixed protrusion on the proximal end of the fiber optic cable with the wall of the 360xc2x0 slot maintains the proximal end of the cable in engagement with the illumination device.
There is a disadvantage with the above-described technique for securing the proximal end of the fiber optic cable to the illumination device. If the proximal end of the fiber optic cable again rotates to the 12:00 position so that the protrusion is aligned with the key slot, the proximal end of the cable can freely disengage from the illumination device with very little force. At all other positions, however, the fiber optic cable cannot be removed from the illumination device without damaging either the cable or the illumination device, because the fixed protrusion on the cable contacts the wall of the 360xc2x0 slot.
In a second technique for securing the proximal end of the fiber optic cable to the illumination device, a 360xc2x0 slot is provided in the proximal end of fiber optic cable. There is no key slot to provide access to the 360xc2x0 slot. Instead, a protrusion is disposed on the wall of the otherwise smooth channel in the illumination device. This protrusion is retractable so that during insertion of the fiber optic cable into the illumination device, a force is required to cause the protrusion to retract. Once the proximal end of the fiber optic cable is sufficiently inserted into the channel in the illumination device, the protrusion on the illumination device is biased into an extended position by a spring so that it engages the 360xc2x0 slot in the fiber optic cable to maintain the cable in engagement with the illumination device.
There is a disadvantage with this retractable protrusion technique for securing the proximal end of the fiber optic cable to the illumination device. The fiber optic cable can disengage from the illumination device if the pull-out force on the cable is large enough to cause the protrusion to retract, regardless of the rotational position of the cable relative to the illumination device. Thus, even though some pull out force is required to cause detachment of the cable from the illumination device, detachment can occur, regardless of the rotational angle of the cable relative to the illumination device, if such a pull out force is applied to the cable.
Accordingly, it is an object of the present invention to provide a phototherapy system that overcomes the shortcomings of conventional phototherapy devices to extend the lifetime of such devices. This object is achieved according to one embodiment of the present invention by providing a phototherapy system that includes a base, a carriage assembly moveably coupled to the base, and a light transmission medium that selectively couples to the base. A first light source and a second light source are coupled to the carriage assembly. The carriage assembly is moveable relative to the base such that in a first position, the first light source is coaxially aligned with a proximal end surface of the light transmission medium to illuminate this surface. When the carriage is in a second position, the second light source is coaxially aligned with the proximal end surface of the light transmission medium illuminate this surface. A sensing device determines when there is a failure of the first light source, and the carriage assembly is automatically moved from the first position to the second position once a failure of the first light source is detected, assuming that the carriage was in the first position. If the carriage was in the second position and the sensing means detects a failure of the second light source, the carriage assembly is moved to the first position.
It is a further object of the present invention to provide a coupling system for selectively securing an end portion of a light transmission medium to an illumination device that overcomes the shortcomings of the coupling systems used in conventional phototherapy devices. This object is achieved according to one embodiment of the present invention by providing a coupling system that includes a collar provided on an illumination device. The collar includes a channel therethrough that receives the proximal end portion of the light transmission medium. A rotation slot is defined in a wall of the channel, and a key slot is also defined in the wall of the channel to provide access to the rotation slot. A fixed key pin is provided on an exterior surface of the end portion of the light transmission medium. The key pin is configured to pass through the key slot and fit within the rotation slot when the proximal end portion of the light transmission medium is inserted into said channel. The key pin is also moveable within the rotation slot once the proximal end portion of the light transmission medium is inserted into the channel to permit swiveling of the proximal end portion of the light transmission medium relative to the collar. A detent pin is provided in the key slot to prevent the key pin from freely disengaging from the rotation slot. The detent pin is moveable between a first position that permits access of the key pin to the rotation slot and a second position that blocks access of the key pin to the rotation slot. Such a coupling system prevents pull out of the light transmission medium from the illumination device in nearly all rotational angles, and over only a relatively small range of angles will some amount of pull out force cause the light transmission medium to decouple from the illumination device.
It is still another object of the present invention to provide a phototherapy system that combines the advantages of the automatic lamp replacement system discussed above and the advantages of the coupling system for selectively securing an end of a light transmission medium to an illumination device in a single phototherapy system.
It is yet another object of the present invention to provide a method of treating a patient using phototherapy that does not suffer from the disadvantages associated with conventional phototherapy techniques. This object is achieved by providing a method that includes first providing a phototherapy system having a base, a carriage assembly moveably coupled to the base, a motor assembly coupled to the carriage assembly for moving the carriage assembly between a first position and a second position, a light transmission medium selectively coupled to the base in a fixed position, a first light source and a second light source coupled to the carriage assembly, and a power supply coupled to the first and second light sources. The method also includes the steps of (1) placing an operative one of the first and second light sources in an operating position in which the light source is substantially coaxially aligned with the proximal end surface of the light transmission medium, (2) energizing the light source placed in this operating position by coupling the light source to the power supply, (3) monitoring whether this light source remains operative, (3) if not, moving the other light source to the operating position, and (4) energizing this other operative light source once it is moved to the operating position.


Various method for repairing a tire tread are provided. In one embodiment, a method for repairing a tire tread comprises: providing a tire having a tire tread portion wherein the tire tread portion includes a tread element that is at least one of a tread block and a tread rib, and wherein the tread element includes a void resulting from wear or damage of the tire tread portion; removing a material from at least a portion of the tread element adjacent to the void to create a removed material portion, wherein the removed material portion includes a specific shape corresponding to a replacement element; applying an adhesive to at least one surface of the removed material portion; applying the replacement element to the removed material portion; and curing the adhesive.

Tires used on vehicles typically wear with use via interaction with the hard surfaces upon which the vehicle is operated. Due to a variety of factors, the wear can be irregular. Irregular wear is generally tire wear that is not uniform across the width of a contact patch of a tire about its entire circumference. For example, some tires may develop heel-toe wear, which may result in tread blocks with higher wear on a heel portion or toe portion (relative to the direction of rotation), and which may be caused by out of specification tire/wheel alignment. Additionally, a tire's tread may wear more in the axially outer edges of the tread, or axially inner portion of the tread, which may be caused by under inflation or over inflation, respectively.
In some instances, tires may develop a localized section of high wear, which may initially be limited to a specific circumferential section of a tire's tread. For example, a tire may experience a circumferentially-localized area of high wear in a shoulder rib/shoulder blocks due misalignment or the input of small steering angle to overcome a road crown. In another example, a tire may experience irregular wear in any localized section of a tread, due to any of a variety of factors. Inevitably, irregular wear that may initially be localized, will propagate through at least some of the rest of the tread, an perhaps circumferentially around the tread. Once the irregular wear propagates, the life of the tire tread is typically much shorter than the same tire tread without irregular wear.
Additionally, a tire's tread may be damaged via contact with sharp rocks, metal, etc. that may be present in a roadway or off-road location. This damage may result in the tire's tread, for example, a tread block, having a large portion cut or torn away. This area of localized damage may propagate due to the void in the ground-contacting portion of the tread.
When irregular wear or tire tread damage is recognized early, and has not propagated through the entirety of the tread, the tire tread may be repaired to extend the life of the tire and delay or prevent propagation of wear. What is needed is a method for repairing a tire tread that experiences uneven wear or damage.

Bridgestone Americas Tire Operations, LLC


Rare earth activated alkaline earth metal fluorohalide stimulable phosphors of tetradecahedral type are disclosed. The stimulable phosphors of tetradecahedral type are represented by the following formula (I): EQU Ba.sub.1-x Ca.sub.x FBr.sub.1-y I.sub.y :aEu,bK,cCs (I). in which 0<x.ltoreq.0.03, 0<y.ltoreq.0.30, 0.0001.ltoreq.a.ltoreq.0.01, 0<b.ltoreq.0.001 and 0.ltoreq.c.ltoreq.0.001, respectively; or the following formula (II): EQU Ba.sub.1-x Ca.sub.x FBr.sub.1-y I.sub.y :aEu,bK,cLi (II). in which 0<x.ltoreq.0.03, 0.ltoreq.y.ltoreq.0.30, 0.0001.ltoreq.a.ltoreq.0.01, 0<b.ltoreq.0.001 and 0.ltoreq.c.ltoreq.0.01, respectively. A radiation image storage panel employing the above phosphor is also disclosed.

As a method replacing a conventional radiography, radiation image recording and reproducing method utilizing a stimulable phosphor is proposed and has been practically employed. In the method, a radiation image storage panel comprising a stimulable phosphor (i.e., stimulable phosphor sheet) is employed, and the method comprises the steps of causing the stimulable phosphor of the panel to absorb radiation energy having passed through an object or having radiated from an object; sequentially exciting the stimulable phosphor with an electromagnetic wave such as visible light or infrared rays (hereinafter referred to as "stimulating rays") to release the radiation energy stored in the phosphor as light emission (stimulated emission); photoelectrically detecting the light emission to obtain electric signals; and reproducing the radiation image of the object as a visible image from the electric signals. The radiation image storage panel thus treated is subjected to a step for erasing a radiation image remaining therein, and then is stored for the next radiation image recording and reproducing procedure. Thus, the radiation image storage panel can be repeatedly employed.
In the radiation image recording and reproducing method, a radiation image is obtainable with a sufficient amount of information by applying a radiation to an object at considerably smaller dose, as compared with the conventional radiography using a combination of a radiographic film and a radiographic intensifying screen. Further, the method is very advantageous from the viewpoint of conservation of resources and economic efficiency, because the radiation image storage panel can be repeatedly used in the method, while the radiographic film is consumed for each radiographic process in the conventional radiography.
The stimulable phosphor gives a stimulated emission (i.e., light emission) when it is irradiated with stimulating rays after it is exposed to radiation. In a general radiation image storage panel, a stimulable phosphor giving a stimulated emission of a wavelength in the range of 300 to 500 nm when it is irradiated with stimulating rays of a wavelength in the range of 400 to 900 nm is employed. One of the typical examples of such generally used stimulable phosphors is a rare earth activated alkaline earth metal fluorohalide phosphor.
The radiation image storage panel employed in the above-described method generally comprises a support and a stimulable phosphor layer provided on one surface of the support. However, if the phosphor layer is self-supporting, the support may be omitted.
As the stimulable phosphor layer, there are known not only a phosphor layer comprising a binder and a stimulable phosphor dispersed therein but also a phosphor layer composed of only an agglomerate of a stimulable phosphor, containing no binder, which is formed through deposition process or firing process. Besides them, a phosphor layer in which voids of stimulable phosphor agglomerate are impregnated with a polymer material is also known. In any of the above-described phosphor layers, the stimulable phosphor emits light (stimulated emission) when excited with stimulating rays such as visible light or infrared rays, after having been exposed to a radiation such as X-rays. Accordingly, the radiation having passed through an object or radiating from an object is absorbed by the phosphor layer of the panel in an amount proportional to the applied radiation dose, and a radiation image of the object is produced in the panel in the form of a radiation energy-stored image. The radiation energy-stored image can be released as stimulated emission by sequentially irradiating the panel with stimulating rays. The stimulated emission is then photoelectrically detected to give electric signals, so as to reproduce a visible image from the electric signals.
A transparent protective film of polymer material or deposited inorganic material is generally provided on the free surface (surface not facing the support) of the phosphor layer to keep the phosphor layer from chemical deterioration or physical shock.
A radiation image storage panel employing the above-mentioned rare earth activated alkaline earth metal fluorohalide phosphor exhibits high sensitivity and gives a reproduced radiographic image with high sharpness, and therefore the stimulable phosphor is very suitable for practical use. However, according as the radiation image recording and reproducing method is getting more practically used, it is desired to further develop stimulable phosphors of high performance.
U.S. Pat. No. 5,534,191 proposes that the conventional rare earth activated alkaline earth metal fluorohalide stimulable phosphor has some problems caused by the fact that the phosphor is in the form of plate-shaped particles. In order to improve the stimulable phosphor, the U.S. Patent proposes a rare earth activated alkaline earth metal fluorohalide stimulable phosphor in the form of tetradecahedral particles represented by a certain elemental composition formula. In the publication, a radiation image storage panel employing the stimulable phosphor of tetradecahedral type is also disclosed.

Rare earth activated alkaline earth metal fluorohalide stimulable phosphor of tetradecahedral type