An improved high speed package printer for producing a plurality of high quality photographs of varying size, shape, and style based on one or a plurality of different film negatives. The improved package printer of the present invention accomplishes the goal of increased throughput and speed through the use of an automatic paper-loading feature, ultrasonic proximity sensors for dynamically measuring paper-slack loops, off-center printing for eliminating the need to advance the paper for punching after each exposure, a rotational prism for creating 10".times.13" photographs without physically rotating the film, a 13-UP lens deck including 12 wallet lenses and a single 5".times.7" retro-focus lens for creating 12 wallet-sized photographs and one 5".times.7" photograph from a single exposure, an automatic diffusion plate cleaner for eliminating the system down time associated with manual diffusion plate cleaning, an improved filtering arrangement for equalizing the amount of energy emitted from each lamp within a photographic lamphouse, and bi-directional film movement for producing a single composite containing a plurality of different images or poses. The high speed package printer of the present invention also boasts an improved film cleaning arrangement for increasing the quality of the prints, as well as penumbra masking for producing photographs having sharply delineated borders.

I. Field of the Invention
The present invention relates generally to a printer for selectively projecting photographic images onto a projection plane containing photographic paper. More particularly, the present invention relates to a high speed photographic package printer for producing a plurality of different sets or packages of photographs based on one or more negatives, wherein the improved package printer boasts an automatic paper-loading feature, dynamically controlled paper-slack loops, off-center printing, a rotational prism for creating 10".times.13" photographs, a 13-UP lens assembly including 12 wallet lenses and a single 5".times.7" retro-focus lens, an automatic diffusion plate cleaner, an improved dichroic lamp filtering arrangement, a focal plane shutter, bi-directional film movement, an improved film cleaner, and improved masking.
II. Discussion of the Prior Art
Photographic package printers have experienced proliferated use and widespread popularity due to their ability to generate custom made photographic packages consisting of selected photographs of varying size, shape, and style based on one or more negatives. Photographic package printers accomplish this by providing a lamphouse from which a beam of light is directed through photographic film onto a projection plane containing photographic paper for producing a print. In order to vary the shape and size of the particular prints, package printers are equipped with a plurality of movable lenses having varying magnification ratios so as to create a wide variety of exposures upon the photographic paper. By way of example and not limitation, package printers are commonly employed for processing the exposed photographic film from annual school photography sessions wherein each student within the school or class is photographed in any number of different poses using one or a plurality of different backdrops. The student may thereafter choose from among the various proofs generated during the photography session to order a custom package containing any number of different size or style photographs, such as wallet-size, 5".times.7," 8".times.10," and 10".times.13" photographs. However, the package printers of the prior art suffer from several substantial drawbacks both in terms of the speed of operation and print quality.
With specific regard to the speed of operation, the prior art package printers have several time limiting features which collectively restrict the ability of the package printers to operate at high speeds. One such drawback is that the prior art package printers typically require considerable time and energy to load the paper into the paper deck for subsequent exposure. Although several attempts have been made to automate the paper loading process, these efforts fail to provide a reliable means for guiding the paper during the loading stage such that significant system down time may be experienced to rectify the situation and reload the paper. For example, U.S. Pat. No. 5,181,066 to Ozawa et al. discloses a paper transporting device for a photographic printer which utilizes retractable bridge members to support the paper during the loading stage, a first pair of drive rollers for drawing the paper into the printer, and a second pair of drive rollers for propelling the paper to a processing section of the printer. U.S. Pat. No. 5,107,296 to Ozawa et al. discloses the use of retractable bridge members for controlling the transportation of the paper between a paper supply cartridge and a processing section. U.S. Pat. No. 4,961,093 also employs retractable bridge members so as to facilitate the loading of paper from a paper supply magazine into exposure apparatus and further to a take-up magazine. U.S. Pat. No. 5,655,583 to Kitai entails maintaining the traveling path of the photographic paper from a supply cartridge to nipping rollers in a straight manner by adjusting the height of an inner frame via elevator means. U.S. Pat. No. 4,566,784 to Nitsch discloses an apparatus for threading a new roll of paper into a photographic copier, comprising a retractable flap which, when disposed in the operative (guiding) position parallel to the paper, forms a passageway for threading the new roll of paper into the photographic copier. However, although the improvements offered in these references provide benefits over manual paper loading, their teachings are nonetheless flawed in that they merely provide guidance along a single surface of the paper, thereby allowing the paper to buckle and become fouled up during the loading process.
Another time limiting feature of the prior art package printers relates to the paper slack loops associated with the drive motors used to load and advance the photographic paper. Paper slack loops are essentially reservoirs containing a length of photographic paper which allows the paper to be advanced quickly into and out of an exposure area within the paper deck by factoring out the inertia of the paper supply spool. U.S. Pat. No. 5,181,066 to Ozawa et al. discloses a pair of loop sensors associated with each paper slack loop for detecting when the particular loop has exceeded a predetermined threshold. U.S. Pat. No. 5,107,296 to Ozawa et al. discloses a loop sensor for detecting a predetermined length of a first loop. U.S. Pat. No. 4,961,093 to Hicks also discloses the use of a pair of sensors for detecting when each particular paper slack loop exceeds a predetermined length. U.S. Pat. No. 5,159,385 to Imamura discloses a photo-lab system having a plurality of loop sensors for controlling the length of the paper within the respective paper loop reservoirs. The paper slack loop sensing arrangements within the above-identified references, however, are flawed in that they are not capable of detecting the actual length of the paper within each respective paper loop reservoirs but rather are merely capable of determining whether the particular paper loops have exceeded a predetermined limit or range. This is disadvantageous in terms of responsiveness in that a lag time exists between the instance that the sensors detect that the paper has exceeded the predetermined threshold and the time that the drive motors are activated to advance the paper, thereby limiting the overall speed at which the package printer can operate.
Another drawback stems from the manner in which 10".times.13" photographs are generated in prior art package printers. The traditional method for generating 10".times.13" photographs in package printers is illustrated in U.S. Pat. No. 5,162,843 to Clapp, wherein the photographic negative is physically rotated within the film deck in order to project a 10".times.13" image on the 10" wide paper. Although effective at producing the 10".times.13" photographs, this technique is particularly disadvantageous in that the mechanical turrets employed to rotate the negative are extremely bulky and heavy. The attendant bulk of the mechanical turret consumes a substantial amount of valuable space within the package printer, while the exorbitant weight limits the speed at which the negative can be rotated and causes substantial vibrations within the package printer which require lengthy settling time. The settling time and rotation time are additive such that the overall amount of time required to generate a 10".times.13" photograph is quite lengthy. Moreover, the mechanical turret can only support a limited amount of photographic film such that the film must be reloaded quite often. This increases the overall down time for the printer which, it will be appreciated, restricts the speed and throughput of these package printers. The mechanical turrets are also flawed in that the bearings are prone to wear out and become damaged through repeated rotation which, once again, leads to increased system down time for repair.
Another significant flaw in the prior art package printers is that they print on-center, that is, the negative is co-aligned with the approximate center of the photographic paper such that the image-bearing light projects in a directly vertical fashion from the negative to the approximate center of the photographic paper. U.S. Pat. No. 5,162,843 to Clapp, for example, discloses one such package printer which employs on-center printing. The main disadvantage of on-center printing is that it requires an extra step of advancing the photographic paper for the purpose of creating marking notches in the paper to indicate the end of each exposure and the end of each entire photographic session. Marking the paper in this fashion aids in the photograph development process in that the processing equipment can be quipped to interpret the various notches in order to automatically process, sort, and package the particular photographs within each photographic session. In order to properly mark each exposure and/or photographic session, the marking notches are preferably placed at or near the leading edge of each photographic exposure on the paper such that the processing components can accurately detect their occurrence. Typically, the marking notches are created through the use of one or more actuating cylinders disposed off-center to the negative. In that the printing is on-center, i.e. directly above the negative, the paper must be advanced after each exposure to accomplish the desired marking before advancing further to avail the next unexposed portion of paper. This is disadvantageous in that the paper must be stopped prior to performing the aforementioned marking process. It will be appreciated by those skilled in the art that the extra step of stopping to conduct punching activities consumes a substantial amount of valuable time.
Still other drawbacks with prior art package printers relate to the task of producing a plurality of differently sized photographs with a single exposure. More specifically, problems result due to the fact that this task is typically accomplished by situating a plurality of lenses having a variety of different magnification ratios on a single assembly within the lens deck. Each particular lens on the assembly has a corresponding focal point which requires the lens to be positioned a predetermined distance from the projection plane in order to produce the desired image on the photographic paper. Thus, each lens has a specific vertical height on the assembly which, in turn, causes the moment of inertia of the assembly to be far removed from the center of gravity of the assembly. This is disadvantageous in that removing the moment of inertia from the center of gravity causes the assembly to experience rocking during movement back and forth within the lens deck, thereby increasing the settling time between exposures. Still a further drawback with producing multiple images with a single exposure is that the ray traces from the various lenses tend to intersect if the number of lenses becomes too concentrated on the assembly. The intersection of ray traces is problematic in that it produces fouled or imperfect images on the photographic paper.
A still further drawback with the package printers of the prior art relates to the ability of the film to be translated during the operation of the package printer. To be more specific, the film within the package printers of the prior art are simply uni-directional, i.e. the film can only progress from the film supply spool to the film take-up spool. In this arrangement, then, the number of different composites which can be formed is very limited in that the various negatives cannot be switched back and forth into position over the lamp house. This effectively limits the range of possible composite photographs which can be accomplished with the package printers of the prior art. In order to overcome this deficiency, separate printers are specifically employed to create composite photographs using a plurality of different negatives. This is disadvantageous, however, in that the package printer and the composite printer will have different color emulsions and, therefore, resulting composites will not share the same color as the prints generated by the package printer. The need for a separate composite printer is also disadvantageous in terms of the time required to perform the custom printing and, moreover, the film and/or paper is subject to an increased risk of damage during the transportation to and from the composite printer.
Yet another drawback with the prior art package printers stems from the fact that the shutter assemblies are disposed above the focal plane. Positioning the shutter above the focal plane is problematic in that it requires a relatively large shutter opening and, therefore, a relatively large assembly to carry the shutter within the printer. The increased mass of the shutter assembly translates into decreased speed of operation in that there is more mass to move back and forth to effectuate a shutter operation. The increased mass of the shutter assembly also translates into increased settling time between shutter operations, thereby adversely affecting the reliability and operating speed of the package printer. Still another problem with positioning the shutter assembly above the focal plane is that interference may result between the shutter assembly and the lower lens assemblies within the lens deck.
Still another time limiting drawback with the package printers of the prior art pertains to the amount of energy consumed by the individual bulbs within the lamp house. To be more specific, the lamp house typically requires combining red, yellow, and green light in specific fashion to ensure for the proper exposure of the photographic paper. To accomplish this, the manufacturers of the lamp houses typically provide multiple (3 or 4) separate white light bulbs with each bulb equipped with a red, yellow, or green filer for creating the colored light. However, red is the predominant color required when creating the exposures on the photographic film and, as such, the underlying light bulb associated with the red filter is typically operated at a higher power than the light bulbs associated with the yellow and green filters. This presents a drawback in that each light bulb associated with a red filter will burn out at a higher frequency than the light bulbs used with the yellow and green filters due to the relatively large amount of power consumed by the red filtered light bulb, thereby increasing the amount of system down time when the burned out bulbs must be replaced.
Still other drawbacks exist in the prior art package printers with respect to print quality. First, the prior art package printers typically do not provide sufficient cleaning means for minimizing the amount of lint, dust, and other airborne contaminants from the surface of the film. For example, a typical film cleaning arrangement entails providing a pair of sticky rollers on the upstream or supply side of the photographic film in an effort to prepare the film for processing. However, such an arrangement is ineffective in eliminating all of the dust and related undesirables from the film so that the photographs may be marred or flawed. In the instance that such dust particles results on the film, it could translate into the ruination of an entire sitting which, as can be appreciated, results in lost profits due to wastefulness. At the very least, it will require manual touching up which, once again, adds to the overall time to create the photographs within each requested package.
Drawbacks also exist in the prior art package printers with regard to their ability to clean the diffusion plates used to equalize the light from the lamp house. For example, U.S. Pat. No. 5,181,066 to Ozawa et al. discloses a diffusion plate for diffusing and equalizing the light passing through the filter assembly of the light source wherein the diffusion plate must be cleaned manually between a predetermined number of sittings. This is flawed in that lint, dust, and other similar particles may come to rest on the diffusion plates such that spotted imperfections form on all the photographs being processed. This can be particularly damaging if the "floaters" are not discovered until after the processing of the exposed paper such that a large portion of the exposures must be repeated, consuming a substantial amount of system down time and resulting in large amounts of scrap and waste.
Yet another flaw in print quality resides in the masking used to crop the image bearing light beam to produce sharply delineated borders. U.S. Pat. No. 5,181,066 to Ozawa et al. discloses a variable mask including a length adjusting mask for adjusting the length of the exposure frame according to the print size, and a width adjusting mask for adjusting the width of the exposure frame according to the paper size and any border required in the print to be made. U.S. Pat. No. 5,287,141 to Yoshikawa also discloses a variable mask in an exposure room which masks the photographic paper in accordance with the particular print size. In similar fashion, U.S. Pat. No. 4,655,583 to Kitai discloses a trimming mask frame provided in conjunction with a press pan. However, these arrangements are incapable of adequately cropping the image bearing light beam to produce a well defined print border.
In light of the foregoing, therefore, a need exists for an improved high speed package printer which is capable of loading the photographic paper in an automatic fashion such that the paper will not be subject to buckling or become fouled in the paper transportation path. The improved high speed package printer should be capable of dynamically measuring the paper slack loops to ensure for the smooth and efficient operation of the paper drive motors. A need also exists for eliminating the need to advance the paper after each exposure to punch the paper at the leading edge of each exposure. The improved high speed package printer should also allow 10".times.13" photographs to be taken without the need for a rotating turret and should be capable of generating 12 wallet sized photographs and a single 5".times.7" photograph with a single exposure. The improved package printer should furthermore be capable of producing folio photographs comprising four different 4".times.5" photographic images, as well as automatically removing all dust particles and "floaters" from the diffusion plate so as to improve print quality. The improved high speed package printer should also be equipped with an improved lamp house filtering arrangement which reduces the degree to which the light bulbs associated with the red filter burn out so as to minimize system down time. The improved high speed package printer should also have an improved film cleaning arrangement for minimizing the amount of dust and related which are able to settle on the film, thereby reducing the amount of scrap and the amount of manual touching up required to salvage the marred photographs. The package printer should furthermore have an improved negative cropping arrangement for producing a sharply delineated print border. Lastly, the improved high speed package printer should have bi-directional film movement so as to increase the range of possibilities with respect to the various photographs included within a particular composite photograph.


A low cost torque transfer device capable of imparting high levels of force and torque to small diameter lead bodies and the like. The torque transfer device of the present invention may be mounted on or peeled off a lead body by the single hand of a user, and may be formed from relatively inexpensive materials using high volume manufacturing methods. An aperture disposed inside the device has inner sidewalls for engaging the outer surface of a lead body, guide wire, catheter or like device.

Endocardial pacing leads may be classified in two broad categories: permanent pacing leads and temporary pacing leads. Permanent and temporary pacing leads are generally characterized in having different physical structures, materials and configurations. Structural differences between the two general types of pacing leads are driven primarily by cost considerations and the different natures of the applications for which the two types of leads are employed. In 1996 U.S. dollars many temporary pacing leads have actual or suggested retail prices in the U.S. that vary between about $75 and $200. In contrast, many permanent pacing leads sold in the U.S. have actual or suggested retail prices exceeding $1,000. Most temporary pacing leads are used for one week or less and then disposed of, while permanent pacing leads often remain implanted and functioning in patients for five years or longer.
When a permanent pacing lead is implanted in a patient, a pacemaker and an electrical connection between the pacing lead and the pacemaker are generally embedded within the body. Permanent pacing leads are commonly implanted with the aid of stylets that increase the speed and accuracy of lead electrode placement. Moreover, once the lead has been implanted and the stylet withdrawn, the remaining lead body becomes flexible and does not retain the stiffness imparted by the stylet. Thus, stylets are highly desirable and often used in permanent leads.
When implanting a permanent pacing lead, a peripheral vein such as the left or right subclavian vein is punctured by an introducer through an incised portion of the skin. A prior art "catheter" or a lead containing a stylet is inserted through the introducer. When a prior art "catheter" is used, the "catheter's" distal end is held at the apex of the right ventricle or right atrium while a temporary lead is inserted through the prior art "catheter" until the distal end of the lead engages and is lodged or otherwise affixed to the endocardium of the right ventricle or right atrium; the prior art "catheter" is then withdrawn. If a lead having a stylet is used, the distal end of the lead is guided to the apex of the right ventricle or the atrial appendage in the atrium, the lead electrode tip is affixed to the endocardium and the stylet is removed. We use the term "catheter" above respecting the prior art because prior art catheters were generally tubes formed from rubber, neoprene or plastic tubes that had no inner braiding or other structural strengthening means that permitted the control or transfer of torque. Thus, the term "catheter," as it applies to the prior art discussed here, does not include within its scope "guide catheters" of the present invention that, contrariwise, do permit the transfer and control of torque from their proximal to distal ends.
It is notable that no permanent leads known to the inventors of the present invention have employed catheters for several decades. The are several reasons why such prior art catheters are no longer used. Prior art catheters could not provide as much torque control or transmission as stylets. The thick sidewalls and correspondingly large diameter of prior art catheters rendered such catheters large in diameter. In fact, many such catheters had such large diameters that they could not be inserted in the cephalic veins of a significant number of patients.
Temporary transvenous endocardial pacing leads are generally used prior to pacemaker implant surgery or in emergency treatment of heart arrythmias and myocardial infarction. In temporary pacing, the distal end of a temporary pacing lead is inserted transvenously in the body using some of the techniques described above for permanent leads while the proximal end is located outside the body where electrical and mechanical connections to an external temporary pacemaker are made. The positive and negative connectors at the proximal end of the temporary lead are connected to the terminals of the temporary pacemaker or patient cable provided for strain relief or extension purposes. (A patient cable is usually, in turn, then connected to a temporary pacemaker.) The temporary pacemaker provides pulses of electrical energy to stimulate the endocardium through the temporary pacing lead. The stimulation rate, output amplitude and sensitivity of the temporary pacemaker are then adjusted. Typically, a temporary pacing lead is extricated and withdrawn from a patient when a permanent, implantable pacemaker and corresponding permanent lead are implanted, or when the need for pacing no longer exists.
Epicardial pacing leads are often used in temporary pacing applications following transthoracic surgery, where the electrode is affixed to the surface of the heart. It is an advantage of endocardial leads that they typically require lower stimulation thresholds to pace the heart than those required with epicardial leads because endocardial leads provide lower stimulation thresholds overtime. Temporary pacing leads should not be reused, are designed to be disposed of after a single use, and are not designed for use over prolonged periods of time.
While low cost temporary pacing leads have been widely used for decades, low cost temporary leads known heretofore have never been used in conjunction with stylets or guide catheters. This may be because stylets and guide catheters add considerable, excessive and therefore unaffordable cost to known temporary pacing lead products, or simply because heretofore no one has previously conceived of combining temporary pacing leads and guide catheters or stylets.
Prior art low cost temporary pacing leads have never included active fixation structures at their distal ends for attaching the lead to the endocardium, despite the clear advantages and benefits of such devices.
Among other reasons, cost considerations have prevented the use of active fixation devices in temporary pacing leads. Active fixation devices generally require expensive sheathing or shrouding structures to protect venous and cardiac tissue from the device during implantation. Such sheathing structures include those retracted to expose the device when the distal end of the lead is positioned at the affixation site, as well as glycol-containing compounds disposed about the active fixation device that slowly dissolve upon being immersed in a warm, sanguine medium. Examples of mechanical sheathing structures for transvenous pacing leads include various distal end sheaths and helical electrodes retractable by stylet means.
Temporary pacing leads known in the prior art fall into two broad categories: (1) coaxial temporary pacing leads, and (2) temporary pacing leads having one, two or three lumens.
Coaxial temporary pacing leads are characterized in having inner and outer conductors separated by an electrically insulative material, where the inner conductor typically comprises three twisted or stranded wires, and the outer conductor typically comprises a woven metallic mesh formed of 16 woven wires. The outermost layer is electrically insulative and is typically formed of urethane, polyurethane or polyethylene. Coaxial temporary leads are usually 6 to 7 French in diameter, but may be as small as 4 French in diameter. Examples of coaxial temporary pacing leads include MEDTRONIC.RTM. Model Numbers 6704, 6704A, 6705 and 6705A TEMPTRON.RTM. leads described in MEDTRONIC publication reference number MC 78-PE-0086c 179562-001, the disclosure of which is hereby incorporated by reference in its entirety. FIG. 1 shows a side cutaway view of a prior art coaxial temporary lead. FIG. 2(a) shows a cross-sectional view of the lead of FIG. 1.
Single, double or tri-lumen temporary pacing leads are characterized in having one, two or three lumens for housing two or more electrical conductors. The conductors are usually electrically insulated from one another by their respective layers of electrical insulation or by lead body electrical insulation. Each conductor typically comprises up to 8 twisted or braided wires disposed within the insulation. Examples of single and double lumen temporary pacing leads include DAIG.TM. temporary pacing lead model numbers 401674, 401675, 401665 and 410666, USCI.TM. temporary pacing lead model numbers 7153, 7151, 7157, 8154, 7150, 8153, 6221, 7406 and 6222, TELECTRONICS CORDIS.TM. temporary pacing lead model numbers 370-230, 370-132, 370-330, 370-136 and 370-420, and ELECATH.TM. temporary pacing lead model numbers 11-KSS5, 11-KSS6, 11-KSS4, 22-0865 and 22-0866. PROCATH CORPORATION.TM. of Berlin, N.J. also manufactures single lumen temporary pacing leads. FIG. 2(b) shows the cross-sectional structure of a prior art single lumen temporary lead having two electrical conductors disposed side by side. FIG. 2(c) shows the cross-sectional structure of a prior art tri-lumen temporary lead having three separate conductors.
Some ideal attributes of a temporary pacing lead include: (1) small lead diameter; (2) secure placement of the tip electrode in the selected heart chamber; (3) high degree of steerability, control and torque transfer during implantation; (4) minimal damage to vein, heart valve and endocardial tissue during implantation; (5) reliable conduction of electrical impulses during use; (6) easy removal from the heart chamber with minimum tissue damage, and (7) low cost.
Small diameter leads are desirable for several reasons. A vein has a finite diameter and thus a finite cross-sectional area for receiving one or more leads. A small diameter temporary lead is accommodated more readily in, and impedes less the flow of blood through, a vein than does a large diameter temporary lead. A small diameter lead also provides minimum interference with the flow of blood through a venous vessel or a heart valve. Large diameter leads are known to adversely affect heart valve operation. Finally, some patients already have at least one implanted lead when an additional temporary pacing lead must be implanted; having a small diameter lead becomes a significant advantage under such circumstances.
Large diameter temporary leads are more likely to rub against and dislodge permanently implanted leads during lead removal than are small diameter temporary leads. Large diameter temporary leads present a greater mass of foreign material to the body, and thus present a higher risk of occlusive thrombosis, scar tissue formation and thrombotic pulmonary embolism than do small diameter temporary leads. Because large diameter leads are generally stiff, they more likely to perforate veins or cardiac tissue, are more prone to lead fatigue and subsequent failure, and may take a long time to place. A primary cause of lead failure is the crushing of large diameter lead bodies between the relatively small space between the clavical and first rib.
Despite the numerous advantages of small diameter leads described above, in practice small diameter leads have proved difficult to manufacture, and are frequently unreliable and difficult to place. For example, many prior art small diameter leads are too pliable to permit sufficient steerability and control for accurate lead placement. Additionally, the high degree of flexibility and limpness characterizing many small diameter leads may lead to excessive time and effort being required for lead placement. In consequence, the cost for the procedure rises and the patient is progressively exposed to more risk factors as the amount of time expended to complete the procedure increases. Finally, most small diameter leads do not transfer sufficient torque between the proximal and distal ends to permit the tip electrode to be affixed to cardiac tissue at a selected site with any degree of accuracy.
Secure placement of the tip electrode in the selected heart chamber is required to assure appropriate and reliable depolarization or "capture" of cardiac tissue by electrical stimuli delivered by the temporary pacemaker. Known temporary transvenous leads suffer from a relatively high rate of dislodgment from sites adjacent or on the endocardium. This is not surprising in view of the fact that no prior art temporary transvenous pacing leads utilize active fixation devices to positively secure the electrode tip to the endocardium. Instead, known temporary pacing leads rely on force provided by a bent or curved lead body as a means of pushing the distal electrode tip against endocardial tissue. If the pacing lead body or tip shifts position as a result, for example, of patient postural changes, the tip electrode may disengage or float away from the endocardium. This, in turn, may result in a loss of capture, or in a reduction of the degree of electrical coupling between the electrode and endocardium.
Treadmill tests can yield valuable information concerning a patient's health and diagnosis that may not be obtained in any other way. Despite their clear benefits, however, physicians rarely prescribe treadmill tests for patients having implanted temporary transvenous pacing leads because temporary pacing leads typically become dislodged easily when patients are ambulatory or otherwise move about. Furthermore, it is common that patients having implanted temporary pacing leads cannot be paced in the DDD mode because at least one of the leads dislodges or becomes poorly coupled electrically to the endocardium after the lead implantation procedure has been completed. This is because it is very difficult to maintain pacing in the atrium over any appreciable length of time when the pacing lead has no means for fixation to the atrial wall.
It is desirable that temporary pacing leads have a high degree of steerability, control and torque transfer to permit relatively quick and accurate placement of the electrode tip at the desired site within the heart, and the initiation of temporary pacing with minimum delay and tissue trauma. Speed and accuracy of lead placement become especially important when attempting to restore a patient's heartbeat under emergency conditions. In the past, there have been a limited number of sites in the atrium and ventricle where lead placement could be effected. The accuracy of where the pacing lead is placed in the atrium or ventricle thus assumes considerable importance.
There are two known means of achieving a high degree of permanent lead steerability and control: (1) placing a stylet in a lumen inside the lead body, and (2) using a guide catheter in conjunction with the lead. Stylets and guide catheters, however, impart significant additional and unaffordable cost to temporary pacing leads, and as a result are not employed in known temporary pacing leads.
Physicians often rely on the tactile feedback and "feel" provided by the lead during implantation for accurate and quick placement. Because of their limpness and excessive flexibility, known small diameter pacing leads typically provide virtually no tactile feedback or "feel" to physicians. Small diameter pacing leads are also notoriously poor at transferring torque between their proximal and distal ends. As a result of the foregoing factors, known small diameter pacing leads generally prove difficult to accurately and quickly place.
Contrariwise, and owing to their stiffness, known large diameter pacing leads often provide a high degree of tactile feedback and "feel." Unfortunately, large diameter pacing leads typically lack sensitivity in the feedback and "feel" they provide. Thus, while known large diameter pacing leads often provide good torque transfer and a high degree of tactile feedback, typically they are also incapable of providing the sensitivity required for a physician to discriminate between endocardial tissue and venous tissue. Consequently, the risk of inadvertently perforating venous or cardiac tissue is made greater with known large diameter pacing leads. Additionally, and owing to their stiffness, large diameter leads exert forces on tip electrodes which promote the growth of scar tissue which, in turn, increases pacing thresholds.
Ideally, temporary pacing leads should cause no damage to vein, heart valve and cardiac tissue during implantation. The temporary lead should have a highly flexible and soft distal tip that readily follows the direction of venous blood flow. Such directional following is often referred to as "floating" the lead or catheter through the venous system. A soft flexible distal tip on the lead or catheter may help prevent trauma to the surrounding venous and cardiac tissues as the lead is directed to the fixation site.
Temporary pacing leads should reliably conduct electrical pulses from the pacemaker even when sutures at the lead anchor suture site are drawn too tight, the lead is stressed by excessive patient movement, or when the pacemaker or attached lead is subjected to rough handling by hospital personnel. Temporary pacing leads are designed for a single use over a limited duration of time, and therefore are typically not constructed of materials that are as biostable, durable, strong or robust as those used in permanent pacing leads. Thus, known temporary pacing leads tend to fail more frequently than permanent pacing leads. Many failures of known temporary pacing leads are caused by fatigue and breaking of electrical conductor wires, electrical insulation that cracks or splits, or electrodes that become pitted or corroded.
When the need for temporary pacing no longer exists, the distal end of the temporary pacing lead should ideally be easily removable from heart chamber. Some known temporary pacing leads suffer from the disadvantage of occasionally damaging heart tissue upon being extracted from the tribiculae in which they are lodged. Other known temporary pacing leads having curved or J-shaped ends for pushing the tip electrode against the endocardium occasionally prove difficult to remove from the heart without at least some tissue trauma occurring.
Finally, temporary pacing leads should be available at low cost, especially since they are used only one time, and then for a very limited duration of time. Heretofore, providing a temporary pacing lead at low cost that has all or most of the foregoing desired attributes has proved impossible, despite the obvious and clear motivations for doing so.
Not surprisingly, no temporary pacing lead known in the prior art has most or all of the above-enumerated desirable safety, performance and cost attributes. What is needed is a low cost, yet still safe, reliable, small diameter, highly steerable, easily removable temporary transvenous endocardial pacing lead capable of reliably capturing, pacing and sensing the heart while causing minimum trauma to heart tissue during implantation and removal.
Transvenous endocardial leads and fetal scalp electrodes are well known in the art, some examples of which may be found in the issued U.S. Patents listed in Table 1 below.
TABLE 1 ______________________________________ Prior Art Patents U.S. Pat. No. Inventor(s) Issue Date ______________________________________ 3,348,548 Chardack Oct. 24, 1967 3,737,579 Bolduc June 5, 1973 3,769,984 Muench Nov. 6, 1973 3,815,611 Denniston, III June 11, 1974 3,827,428 Hon et al. Aug. 6, 1974 3,893,461 Preston July 8, 1975 3,903,896 Harmjanz Sept. 9, 1975 3,915,174 Preston Oct. 28, 1975 4,010,755 Preston March 8, 1977 4,106,512 Bisping Aug. 15, 1978 4,112,952 Thomas et al. Sept. 12, 1978 4,180,080 Murphy Dec. 25, 1979 4,214,594 Little Jul. 29, 1980 4,233,992 Bisping Nov. 18, 1980 4,271,847 Stokes June 9, 1981 4,280,512 Karr et al. Jul. 28, 1981 4,282,885 Bisping Aug. 11, 1981 4,475,560 Tarjan et al. Oct. 9, 1984 4,602,645 Barrington et al. July 29, 1986 4,699,157 Shonk Oct. 13, 1987 4,762,136 Baker, Jr. Aug. 9, 1988 4,799,499 Bisping Jan. 24, 1989 4,819,661 Heil, Jr. et al. April 11, 1989 4,886,074 Bisping Dec. 12, 1989 5,099,839 Miyata et al. March 31, 1992 5,246,014 Williams et al. Sept. 21, 1993 5,261,417 Osypka Nov. 16, 1993 5,261,419 Osypka Nov. 16, 1993 5,314,462 Heil, Jr. et al. May 24, 1994 5,356,427 Miyata et al. Oct. 18, 1994 ______________________________________
All patents listed in Table 1 hereinabove are hereby incorporated by reference herein in their respective entireties. As those of ordinary skill in the art will appreciate readily upon reading the Summary of the Invention, Detailed Description of the Preferred Embodiments and Claims set forth below, many of the devices and methods disclosed in the patents of Table 1 may be modified advantageously by using the teachings of the present invention.

Torque transfer device for temporary transvenous endocardial lead


The present invention provides an optically active poly(diphenylacetylene) compound represented by the following formula (I):

Organic compounds include many optical isomers having completely the same physical, chemical properties, for example, properties such as boiling point, melting point, solubility but showing different physiological activities. In the technical field of medicaments, differences in the pharmacological activity depending on the easiness of binding with a particular receptor in the body have been studied much, and it is widely known that remarkable differences in drug efficacy and toxicity are often found between optical isomers. Guideline for drug production by the Ministry of Health, Labour and Welfare also describes that it is desirable to study absorption, distribution, metabolism and excretion kinetics of each isomer when a racemate is used as a drug.
As described above, since optical isomers show completely the same physical and chemical properties, they cannot be analyzed by general separation means. Thus, the study of techniques for easily and precisely analyzing optical isomers of a wide variety of organic compounds has been extensively conducted. Of such techniques, particularly, the optical resolution method by high performance liquid chromatography (hereinafter sometimes to be also referred to as HPLC) separates optical isomers by using a substance having an ability to separate optical isomers, i.e., an optical isomer separating agent, per se, or a chiral stationary phase supporting an optical isomer separating agent on a suitable carrier by a chemical bond or coating. For example, a packing material comprising an optically active crown ether compound, which is a low-molecular-weight compound, coated on a carrier (patent document 1), a packing material comprising an optically active triphenylmethyl methacrylate polymer, which is a synthetic polymer, coated on a carrier (patent document 2), a packing material comprising cellulose triacetate, which is a polysaccharide derivative, coated on a carrier (patent document 3), a packing material comprising cellulose benzoate coated on a carrier (patent document 4), a packing material comprising cellulose phenylcarbamate coated on a carrier (patent document 5), a packing material comprising a cellulose or amylose derivative (non-patent document 1), ovomucoid which is a protein (patent document 6) and the like have been developed and, in view of their high optical resolution ability, commercialized and widely used.

Optically active poly(diphenylacetylene) compound, preparation method therefor, and use thereof as optical isomer separating agent

Abstract: [wherein each symbol is as described in the DESCRIPTION], and a production method thereof, an optical isomer separating agent containing the poly(diphenylacetylene) compound, and a packing material for a chiral column, containing the optical isomer separating agent coated on a carrier. According to the present invention, a practical optical isomer separation agent having a high optical resolution ability for a wide variety of racemic compounds and an optical isomer separation method can be provided.

NATIONAL UNIVERSITY CORPORATION KANAZAWA UNIVERSITY


Decorative laminates having an open-cell foam layer are disclosed herein. An example decorative laminate includes a decorative layer, an open-cell foam layer coupled to the decorative layer and an adhesive layer coupled to the open-cell foam layer.

Vehicles (e.g., mass transit vehicles, tractor-trailers, personal automobiles, etc.), buildings and/or other structures (e.g., billboards) include surfaces that are visible to people. These surfaces often include decorative images for aesthetic, informational and/or advertising purposes. For example, some interior surfaces of aircraft and/or other mass transit vehicles (e.g., buses, trains, ships, etc.) include decorative images that identify the mass transit provider (e.g., an airline carrier) and/or advertise for another entity, product or service. In some instances, the decorative images are formed by a decorative laminate that is coupled to a surface of the vehicle, building and/or other structure.


A semiconductor device comprises a semiconductor substrate including a diffusion area, a capacitor provided above the semiconductor substrate and including a lower electrode, a dielectric film, and an upper electrode, a plug provided between the semiconductor substrate and the capacitor and having a lower end connected to the diffusion area and an upper end connected to the lower electrode, and a dummy plug provided between the semiconductor substrate and the capacitor and having a lower end not connected to the diffusion area and an upper end connected to the lower electrode.

1. Field of the Invention
The present invention relates to a semiconductor device including a capacitor provided above a semiconductor substrate and a plug which connects the capacitor and a diffusion area on a surface of the semiconductor substrate and a method for manufacturing the same.
2. Description of the Related Art
In recent years, much effort has been made to develop ferroelectric random access memories (FeRAM) that are nonvolatile memories utilizing a ferroelectric thin film. As a capacitor dielectric film in the FeRAM, a ferroelectric thin film is used which comprises a material such as PZT (Pb (Zrx, Ti1-xO3), BIT (Bi4Ti3O2), SBT (SrBi2T2O9), or the like.
For capacitor structures, much effort has been made to develop COP (Capacitor On Plug) structure having a capacitor placed on a plug (for example, Jpn. Pat. Appln. KOKAI Publication No. 2002-289810). In the COP structure, a plug connected to an active area of a transistor is placed immediately below the capacitor. Thus, the employment of the COP structure enables a reduction in cell size as in the case of a stacked capacitor structure for a DRAM.
In a process of manufacturing an FeRAM, thermal treatment is carried out in an oxygen-containing atmosphere in order to recover from damage to the capacitor dielectric film. On this occasion, the plug under the capacitor is oxidized. The oxidized capacitor may increase the contact resistance between the plug and a lower electrode of the capacitor or cause the lower electrode to peel off.
To prevent an increase in contact resistance and peel-off of the lower electrode, attempts have been made to use a noble metal such as iridium, as a material for the lower electrode. This is because the noble metal does not allow oxygen to pass through easily and remains conductive even after oxidation.
On the other hand, silicon is often used as a material for the plug. In this case, since the noble metal is likely to react with silicon, a metal silicide film such as a titanium silicide film is provided between the plug (Si) and the lower electrode (noble metal) as a barrier film.
An oxide film is prone to be formed on a surface of the metal silicide film. Thus, an oxide film formed on the surface of the metal silicide film is removed by, for example, a process using a diluted fluoric acid before the lower electrode is formed.
In this case, the metal silicide film is etched at a lower etching rate than a surrounding silicon oxide film in which the plug is buried. As a result, as shown in FIG. 13, an upper part of a metal silicide film 81 on a plug 80 projects from a surface of a silicon oxide film 82. When there is such a projection of the metal silicide film 81 (a plug structure with a step) below an area in which the lower electrode is formed, the lower electrode is prone to peel off. Further, the projecting part of the metal silicide film 81 may be cracked. In this case, oxygen passes through the crack and reaches the inside of the plug 80. As a result, the plug 80 is oxidized to increase the contact resistance.

Semiconductor device and method for manufacturing the same


Disclosed is an inexpensive fluid dynamic bearing device exhibiting high bearing performance and long life. A fluid dynamic bearing device (1) is mainly composed of a shaft member (2), and a bearing member (7) equipped with a cylindrical radial bearing surface (A) opposed to an outer peripheral surface (2a) of the shaft member (2). The bearing member (7) is formed by injection molding with an electroformed portion (10) inserted, and the radial bearing surface (A) is formed on the electroformed portion (10). Further, a thrust bearing surface (B) is formed on an upper end surface (7b) of the bearing member (7), and the shaft member (2) is supported in a thrust direction by a dynamic pressure action of a lubricating fluid generated in a thrust bearing gap opposed to the thrust bearing surface (B).

1. Field of the Invention
The present invention relates to a fluid dynamic bearing device and a motor equipped with the same.
2. Description of the Related Art
A fluid dynamic bearing device rotatably supports a shaft member by means of a fluid film formed in a bearing gap. Such fluid dynamic bearing devices are roughly classified into ones equipped with a dynamic pressure generating portion for generating dynamic pressure in a lubricating fluid in the bearing gap (so-called dynamic pressure bearings), and ones equipped with no dynamic pressure generating portion. Both types exhibit superior characteristics in terms of high speed rotation, high rotational precision, low noise, etc. In view of those characteristics, a fluid dynamic bearing device is widely suitable for use in, apart from a fan motor mounted in a personal computer (PC), etc., small motors for information apparatuses, for example, a spindle motor mounted in a magnetic disk apparatus such as an HDD and an FDD, an optical disk apparatus such as a CD-ROM, CD-R/RW, and DVD-ROM/RAM, and a magneto-optical disk apparatus such as an MD and an MO, and a polygon scanner motor mounted in a laser beam printer (LBP) or the like.
For example, in a fluid dynamic bearing device for a fan motor, which is among the various motors mentioned above, a rotor with vanes is supported radially by a radial bearing portion so as to be rotatable. Further, a reaction force (thrust force) of the blowing action generated by the vanes is supported by an axial component of a magnetic force generated between a stator coil and a rotor magnet, and a thrust load due to a difference between the magnetic force and the thrust force is supported by a thrust bearing portion. In many cases, in a bearing device for a fan motor, a dynamic pressure bearing is adopted as the radial bearing portion, and a so-called pivot bearing in which the axial end of a rotation shaft is held in contact with a receiving member, is adopted as the thrust bearing portion (see, for example, JP 2000-46057 A).
As an example of a fluid dynamic bearing device for a spindle motor, a structure as shown in FIG. 25 is known. In this fluid dynamic bearing device, there is provided, between the outer peripheral surface of a shaft member 100 and the inner peripheral surface of a bearing member 200 opposed thereto through the intermediation of a radial bearing gap, a radial bearing portion 400 supporting the shaft member 100 radially in a non-contact fashion. Further, there are provided, between the end surfaces of a flange portion 110 provided on the shaft member 100 and members opposed thereto through the intermediation of thrust bearing gaps (bearing member 200 and cover member 300), thrust bearing portions 500 supporting the shaft member in the thrust direction in a non-contact fashion.
In recent years, in particular, in information apparatuses with disk apparatuses incorporated therein, with the rapid progress in performance, a reduction in size and thickness is also being aimed at, and there is an increasingly strict demand for a reduction in the size of a fluid dynamic bearing device. However, in the fluid dynamic bearing device construction as shown in FIG. 25, in which the radial bearing portion and the two thrust bearing portions are stacked together in the axial direction, the axial dimension of the bearing device is generally large, and there are limitations in a reduction in size.
In view of this, there has been disclosed, for example, a construction in which the shaft member is formed in a truncated-cone-like configuration, with a bearing member of a sintered metal being arranged in the outer periphery thereof; there is formed between the shaft member and the bearing member a bearing gap (inclined bearing gap) whose diameter is large on one axial side and small on the other axial side, and a thrust bearing gap is formed between an end surface of the shaft member and a closing member opposed thereto. With this construction, there is no need to provide the flange portion 110 of the shaft member 100 shown in FIG. 25, so it is possible to make the axial dimension of the bearing device so much the smaller (see, for example, JP 2002-276649 A).
In the fluid dynamic bearing device disclosed in JP 2000-46057 A, grooves (dynamic pressure generating portions) for generating fluid dynamic pressure in the radial bearing gap is formed simultaneously with the formation of the bearing member. In this system, however, it is rather difficult to secure a sufficient degree of precision for the dynamic pressure generating portions. Further, since the thrust bearing portions are formed by pivot bearings, wear due to long-term use of the bearing device is inevitable, and there is a fear of this wear adversely affecting the rotational accuracy. Further, the pivot bearing is disadvantageous also from the viewpoint of securing the requisite load capacity (moment rigidity) with respect to moment load.
In the fluid dynamic bearing device disclosed in JP 2002-276649 A, in order to form the inclined bearing gap, it is necessary to form the outer peripheral surface of the shaft member and the inner peripheral surface of the bearing member as conical surfaces. However, it is by no means easy to form the conical surfaces by machining accurately and efficiently. In particular, as compared with the outer peripheral surface, the inner peripheral surface is more difficult to form, so, with the current state of the art, it is rather difficult to finish the conical inner peripheral surface of the bearing member with high accuracy and at low cost; thus, it goes without saying that it is very difficult to secure the requisite precision for the dynamic pressure generating portions when providing the dynamic pressure generating portions such as dynamic pressure grooves, in the conical inner peripheral surface of the bearing member. The bearing performance of a fluid dynamic bearing device, including rotational accuracy, greatly depends on the precision of the bearing gap. Thus, it is impossible to obtain in a stable manner a high precision bearing gap, so a satisfactory bearing performance may not be attained depending upon the design condition, etc.

Fluid dynamic bearing device and motor equipped with the same


A method for preparing a melamine salt of pentaerypolyol phosphoric acid is provided. The method comprises the following steps of: ball milling a mixture of pentaerypolyol and phosphorus pentoxide (P2O5) under a solvent-free reacting environment to obtain a pentaerypolyol phosphoric acid, and ball milling a mixture of a pentaerypolyol phosphoric acid and melamine without organic solvent reacting environment to obtain a melamine salt of pentaerypolyol phosphoric acid.

1. Field of Invention
This invention relates to a method for preparing a flame retardant material and in particular to a method for preparing a melamine salt of pentaerypolyol phosphoric acid.
2. Related Art
Conventional processes for manufacturing flame retardant materials or flame retardant additive materials, applied for electric wire, connect wire, wiring board or hot melt glue, such as a polyolefin flame retardant material containing phosphorous, oxygen and carbon, are all involving chemical processes using a large amount of organic solvents as reaction medium and catalysts.
For example, in U.S. Pat. No. 6,833,467 to Ma issued Dec. 21, 2004 and in U.S. Pat. No. 6,737,526 to Ma issued May 18, 2004, a large amount of toluene solvent, together with pentaerythritol and phosphorus pentoxide reactants, was used to run the two step esterification followed by the next step of neutralization with melamine to form melamine salt of bis-(pentaerythritol phosphate) phosphoric acid and melamine salt of pentaerythritol phosphoric acid. Also used in the two-step esterification process is a metal halide catalyst.
The main concept of the above inventions is to introduce a ball milling mechanochemical manufacturing process. However, since a large amount of organic solvents is used in that reaction, the environment requirements are hard to satisfy. In order to satisfy the environment requirements, the costs for pollution control must increase and will thus lead to an economically unsuccessful production. Besides, the use of a catalyst will also increase impurities of the products.
U.S. Pat. No. 4,454,064 discloses a method for preparing pentaerythritol phosphate regarding a reaction between pentaerythritol and phosphorus oxychloride reactants in a dioxane solvent under a temperature of 75 to 125° C. This is a useful intermediate in the preparation of flame-retardant materials, polyurethanes, and plasticizers.
U.S. Pat. No. 4,478,998 discloses a method for preparing an amino-s-triazine salt containing phosphoric acid, which is represented by the following formula,
in which the X and X′ are ammonium groups, therefore the salt will be a melamine salt of bis-(pentaerythritol phosphate) phosphoric acid. The salt can be used as a flame retardant additive for some specific polymer compositions.
However, the preparing methods as mentioned above all involve the usage of a large amount of solvents and will generate hydrochloric acid vapor, for which a large amount of water is required to wash away HCl from the product mixture, and solution containing excess POCl3 (phosphorus oxychloride) during the reaction, which will hardly ever satisfy the environment requirement and will increase the cost when taking the expenses for the environment requirement in mind.

Method for preparing melamine salt of pentaerypolyol phosphoric acid

Chung Shan Institute of Science and Technology


A fan chassis includes: a wall panel; and an upper panel that is connected to an upper end of the wall panel, and a lower panel that is connected to a lower end of the wall panel. A cross sectional shape of the upper panel and the lower panel is substantially U-shape. The wall panel includes a plurality of projections to be inserted into mounting holes of a fan. At least either one of the upper panel and the lower panel includes a through hole into which an upper end part or a lower end part of the fan is to be fitted. An inner dimension between the upper panel and the lower panel is shorter than an outer dimension of the fan in a vertical direction. The upper panel and the lower panel deform elastically in a direction in which the upper panel and the lower panel move apart from each other.

Heretofore, when operating an electronic device such as a server or a communication device that has a plurality of built-in printed circuit boards in the interior of the casing, a fan, in which a fan and an electric motor are integrated (also referred to as a fan motor), is generally used to discharge heat within the casing. For example, Patent Document 1 discloses a method of attaching a fan to a communication device. In this method, unitization is realized by attaching a fan to a chassis that is formed by means of sheet metal working. Then, this fan unit is inserted and fixed in a slot provided in the front surface of the casing of the communication device.
The fan unit is provided with a control circuit board for supplying electric power and for control, and a connector that is provided on this control circuit board to electrically connect the communication device body and the control circuit board. The type of this connector is generally a type that completes connection to the mother board of the casing by inserting the fan unit into the slot (hereunder, referred to as plug-in unit type). The slot includes a guide structure for connecting the fan unit to the mother board. Moreover, between the inner wall of the slot and the fan unit, there is required a clearance necessary for absorbing manufacturing tolerances of each component.
[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. H10-178291

Fan chassis, fan unit, and communication device


Disclosed herein is an X-ray imaging apparatus including: an X-ray generator including a first X-ray source configured to irradiate a first X-ray onto an object, and at least one second X-ray source spaced apart from the first X-ray source and configured to irradiate at least one second X-ray onto the object; an X-ray detector configured to detect the first X-ray which has propagated through the object and the at least one second X-ray which has propagated through the object; and an image processor configured to produce a first X-ray image of the object based on the detected first X-ray, to produce at least one second X-ray image of the object based on the detected at least one second X-ray, and to produce a stereoscopic image of the object based on the first X-ray image and the at least one second X-ray image.

1. Field
Exemplary embodiments relate to an X-ray imaging apparatus which is configured for irradiating X-rays onto an object to produce an X-ray image, and a control method thereof.
2. Description of the Related Art
An X-ray imaging apparatus is used to check, diagnose, or detect the internal materials, tissue, or structure of an object, such as a human body, an animal, or a baggage case, using X-rays (also called Roentgen rays). Specifically, the X-ray imaging apparatus is used to detect an abnormal tissue or material, such as a human body's inside lesions, in order to understand the inside structure of an object or a component, or to scan baggage at an airport.
The X-ray imaging apparatus visualizes the inside of an object, such as a human body, by placing the object on a stand or at a predetermined location, irradiating X-rays onto the object in a specific direction, for example, in a vertical direction or in a horizontal direction, then detecting the X-rays which propagate through the object, and producing an X-ray image based on the detected X-rays.
The X-ray imaging apparatus visualizes the inside structure of an object based on a phenomenon that X-rays show different transmission or absorption characteristics based on the properties (for example, densities) of materials constituting an object.
The X-ray imaging apparatus includes Computed Tomography (CT), Full Field Digital Mammography (FFDM), and an X-ray imaging apparatus for angiography, which produce X-ray images by using different kinds of X-rays.
When the X-ray imaging apparatus for angiography is used, an intervention specialist makes an incision of about 3 mm in a target area of a patient's skin, inserts a thin tube of about 2 mm called a catheter into the patient's blood vessel, and injects a medication such as a contrast medium so that the patient's blood vessels (veins and arteries) are shown through an X-ray image. An X-ray imaging apparatus for angiography, which is generally used for angiography at hospitals, provides two-dimensional (2D) X-ray images in real time using a single X-ray source and an X-ray detector. Accordingly, when a specialist performs a procedure with operation tools (e.g., catheter) while seeing complicated blood vessel images, the specialist may have difficulty in distinguishing the front and rear locations of the blood vessels and the front and rear locations of the tools and the blood vessels.

X-ray imaging apparatus and control method thereof


A process for thermoforming a sheet of poly(methyl methacrylate) which has a reduced viscosity of at least 1.5, protected on at least one of its faces, by a film, in intimate contact with it. The film is an ethylene polymer which has undergone a corona discharge treatment. The ethylene polymer film is coated with a layer of acrylic adhesive after the ethylene polymer film has undergone the corona treatment.

Traditionally, the surface of the thermoplastic sheets, such as PMMA sheets, has been protected during their transport and their handling before the thermoforming by sticking sheets of paper on them. The adhesives used for this purpose have been generally water-soluble adhesives applied in solution form. However, it was necessary to apply these adhesives very uniformly to the surface of the sheet.
Since an application of an adhesive is very difficult to implement on an industrial scale, it was then proposed to replace the paper with an ethylene polymer film. This eliminates the need to use the adhesive. In the case of the protection of cast PMMA sheets, the ethylene polymer film is applied with the aid of hot rolls. However, when the PMMA sheet is freed from its ethylene polymer film before the thermoforming, the high static charge present on the sheets introduces the disadvantages that the people handling these sheets may be subjected to an electric shock. Also, dust is attracted more strongly into contact with the sheets.
To overcome these disadvantages, it has been proposed, in accordance with French Patent No. 2,349,425, to keep the polyethylene protection on the PMMA sheet during the thermoforming. This also provides the additional advantage of keeping this same protection on the wrought product. In many cases, and especially in that of the products intended to form sanitaryware, it was essential to apply a new protective coating because of the many handling operations which still remain to be performed before the fixture is installed on the consumer's premises.
This known process relates, therefore, to the thermoforming of a PMMA sheet, defined as having a reduced viscosity of at least 1.5 and, preferably, of at least 3.0, such as determined at 25.degree. C. on a chloroform solution containing 1 g of the polymer in 1000 cm.sup.3 of solution. The PMMA sheet is protected, on at least one of its surfaces, by a film, in intimate contact therewith, of a polyethylene which has been subjected to a corona discharge treatment (or corona treatment) at least on the face adhering to the PMMA sheet. In accordance with this known process, the protected PMMA sheet is heated to a temperature of at least 140.degree. C., until it is softened by the heat. The heating is not sufficiently long for the sheet to be damaged by the changes induced in the polyethylene by the heat treatment to which it is subjected. The assembly, consisting of the sheet and its protection, is then deformed until the desired final shape is obtained. The polyethylene is still in intimate contact with the sheet. In accordance with this French patent, it is recommended to employ a film of polyethylene which has a melt flow index, determined according to ASTM Standard 1238-70, ranging from 1 to 4 g/10 min., the preference being given to the range from 2 to 3 g/10 min.
Apart from the conditions which it must fulfil to be capable of being used in the process indicated above, and which are sometimes the result of a compromise to satisfy at the same time the requirements of protection of the PMMA sheet, of temporary adhesiveness and of thermoforming, the ethylene polymer film must be capable, after the thermoforming, of retaining its integrity of appearance and of color until the time when it is to be pulled off. At that time, it must be capable of being pulled off easily, even after prolonged storage. Once pulled off, it must not have left any traces, nor have induced interfering microdeformations (micropits) on the PMMA sheet.

Thermoformed poly (methyl methacrylate) sheets with protective film and adhesion layer


The subject invention pertains to novel materials and methods for use in delivering and sequestering substances, such as pharmacological agents, within a patient. One aspect of the invention is directed towards core-shell particles having a core encapsulated within a calcium carbonate shell, with an intermediate layer composed of an amphiphilic compound surrounding the core. When the particles of the subject invention are administered to a patient, they are capable of removing lipophilic drugs by absorption of the drug through their mineral shell and into their core. The particles of the subject invention can also be administered to a patient as controlled release, drug delivery vehicles. Thus, in another aspect, the subject invention concerns a method of delivering pharmacological agents by administering the core-shell particles of the subject invention to a patient in need of such administration.

Treatment of drug overdose in humans, whether due to therapeutic miscalculation, illicit drug use, or suicide attempt, presents a major problem to the health care industry worldwide. In the United States alone, over 300,000 patients are admitted to the emergency rooms because of drug overdose. Treatment of these patients costs the healthcare industry over ten billion dollars because of hospital expenses and lost employee productivity. This does not include the $80 billion associated with alcohol abuse (Moudgil, B. M., Seventh Year Annual Report. 2001: Engineering Research Center for Particle Science and Technology, University of Florida).
Current treatment protocols for overdosed patients vary with the drug of concern, but are focused on three objectives: prevention of drug absorption, enhancement of drug excretion, and administration of pharmacological antidotes. The first two are accomplished with techniques nonspecific to the ingested drug, such as emesis, gastric lavage, or use of activated charcoal for the former objective, and dialysis or hemoperfusion for the latter. However, since absorption of toxic drugs is very time sensitive, and since these techniques are applied only once a patient reaches the emergency room, they are not as effective as would be desired, with some techniques reported to recover only 30% of the ingested drug (Rumack, B. H., Poisoning: Prevention of absorption, in Poisoning and Overdose, M. J. Bayer and B. H. Rumack, Eds., 1983, p. 13–18). There also currently exist very few specific pharmacological antidotes to the drugs frequently associated with life threatening overdose cases (Moudgil, B. M., Seventh Year Annual Report. 2001: Engineering Research Center for Particle Science and Technology, University of Florida).
An important factor influencing drug distribution in the body is the ability of toxins to bind to blood proteins and tissues. Certain tissues have strong binding affinities for specific toxins, causing localized concentration in that tissue. This is true especially of the kidney and liver, because of their metabolic and excretory functions. Some toxins bind noncovalently to albumin, a blood plasma protein, or other proteins. While bound to protein, the complex becomes pharmacologically inert and is trapped in the bloodstream due to its large size. Only unbound drugs are able to cross lipoprotein membranes and exert an effect. A drug's free molecule concentration is likely to increase during an overdose, since protein-binding sites are more readily saturated. Therefore, it is expected that a patient with low levels of albumin will experience higher toxicity effects than a patient with normal levels (Lu, F., Basic Toxicology: Fundamentals, Target Organs, and Risk Assessment. 3rd ed. 1996, Taylor and Francis: Washington; Fenton, J. J., Toxicology: A Case-Oriented Approach. 2002, CRC Press: Boca Raton; Stine, K. E. and T. M. Brown, Principles of Toxicology. 1996, CRC Press: Boca Raton).
Micron-scale and nano-scale core-shell particulate systems, either hollow or fluid-filled, have become of recent interest. Core-shell particles find important applications in encapsulation of a variety of materials for catalysis and controlled release applications (e.g. drugs, enzymes, pesticides, dyes, etc.); for use as filler in lightweight composites, pigment, or coating materials; and in biomedical implant materials (Putlitz, B. Z. et al., Adv. Mater., 2001, 13:500-+; Walsh, D. and Mann, S., Nature, 1995, 377:320–323; Walsh, D. et al., Adv. Mater., 1999, 11:324–328; Zhong, Z. et al., Adv. Mater., 2002, 12:206–209; Caruso, F., Chem.-Eur. J., 2000, 6:413–419).
Recently, the use of particulate systems as a treatment for patients overdosed on lipophilic drugs has been proposed (Moudgil, B. M., Seventh Year Annual Report. 2001: Engineering Research Center for Particle Science and Technology, University of Florida). Several particulate systems, including microemulsions, polymer microgels, silica nanotubes and nanosponges, and silica core-shell particles, are currently being investigated for this detoxification purpose. It has been proposed that, when intravenously administered to an overdosed patient, such particles will effectively detoxify the patient's circulatory system of the particular lipophilic toxin by either: (a) absorption, from the selective partitioning of the drug molecules from the blood to the hydrophobic core of the particle; or (b) adsorption of the drug molecules onto surfaces of surface-functionalized particles. Furthermore, in order to catalyze the toxin metabolism, and hence its removal from the blood, the immobilization of toxin-specific catabolic enzymes on or within particles is being pursued (Moudgil, B. M., Seventh Year Annual Report. 2001: Engineering Research Center for Particle Science and Technology, University of Florida).
Fabrication of hollow sphere particles has been accomplished using various methods and materials. In general, three fabrication classes are currently employed: sacrificial cores, nozzle reactor systems, and emulsion or phase separation techniques (Caruso, F., Chem.-Eur. J., 2000, 6:413–419; Wilcox, D. L. and Berg, M., in Materials Research Society, 1994, Boston: Materials Research Society). The first involves the coating of a core substrate with a material of interest, followed by the removal of the core by thermal or chemical means. In this manner, hollow particles of yttrium compounds (Kawahashi, N. and Matijevic, E., J Colloid Interface Sci., 1991, 143:103–110), TiO2 and SnO2 (Zhong, Z. et al., Adv. Mater., 2002, 12:206–209), and silica (Caruso, F., Chem.-Eur. J., 2000, 6:413–419) have been synthesized. Nozzle reactor systems make use of spray drying and pyrolysis, and their use has successfully led to the fabrication of hollow glass (Nogami, M. et al., J. Mater. Sci., 1982, 17:2845–2849), silica (Bruinsma, P. J. et al., Chem. Mater., 1997, 9:2507–2512), and TiO2 (Iida, M. et al., Chem. Mater., 1998, 10:3780) particles. Emulsion-mediated procedures, or hollow particle synthesis, is a third common method. This has been used to form latex (Putlitz, B. Z. et al., Adv. Mater., 2001, 13:500-+), polymeric (Pekarek, K. J. et al., Nature, 1994, 367:258–260), and silica core-shell particles (Underhill, R. S. et al., Abstracts of Papers of the American Chemical Society, 2001, 221:545).
Calcium carbonate coated core-shell particles have also been synthesized. By coating polystyrene beads with calcium carbonate, followed by removal of the polymer core, hollow particles in the 1 μm to 5 μm size range have been generated (Walsh, D. and Mann, S., Nature, 1995, 377:320–323; U.S. Pat. No. 5,756,210). Core-shell particles have also been synthesized using water-in-oil (Walsh, D. et al, Adv. Mater., 1999, 11:324–328; Enomae, T., Proceedings of the 5th Asian Textile Conference, 1999, 1:464–467), and water-in-oil-in-water (Hirai, T. et al, Langmuir, 1997, 13:6650–6653; Hirai, T. and Komasawa, I., Kagaku Kogaku Ronbunshu, 2001, 27:303–313) emulsions as templates for calcium carbonate nucleation. In other processes, Lee et al. (Lee, I. et al., Adv. Mater., 2001, 13:1617–1620) and Qi et al. (Qi, L. M. et al., Adv. Mater., 2002, 14:300) respectively use monolayer-protected gold particles and double-hydrophilic block copolymer (DHBC)-surfactant complex micelles as templates for calcium carbonate deposition, resulting in core-shell particles up to 5 μm in diameter.
Some of the calcium carbonate core-shell systems discussed in the scientific literature are generated by using a biomimetic process (Walsh, D. and Mann, S., Nature, 1995, 377:320–323; Walsh, D. et al., Adv. Mater., 1999, 11:324–328; Hirai, T. et al., Langmuir, 1997, 13:6650–6653; Hirai, T. and Komasawa, I., Kagaku Kogaku Ronbunshu, 2001, 27:303–313; Qi, L. M. et al., Adv. Mater., 2002, 14:300). Mineralization in biological systems has been the focus of intense research because their successful mimicry has important implications for the synthetic design of superior materials. Exquisite control of mineral deposition in biosystems is thought to occur partly due to the presence of an insoluble organic matrix, along with modulation of the crystal growth process via soluble macromolecular species, such as acidic proteins and polysaccharides (Lowenstam, H. A. and Weiner, S., On Biomineralization, Oxford University Press: New York, 1989).
As can be understood from the above, there remains a need for a particulate system that is capable of neutralizing or eliminating toxic levels of drugs within a patient in a short period of time, and which can be produced with the high degree of control associated with biomimetic processes.

Materials and methods for drug delivery and uptake


To match the output frame rates to the input frame rates, a display clock signal is generated that has a frequency locked to the frequency of a reference clock signal. To generate the display clock signal, the period of the vertical incoming data clock is measured using the reference clock signal. The number of pixels disposed in the output frames is subsequently divided by the measured period. A fractional-N phase-locked loop circuit is adapted to multiply the result of the division with the frequency of the reference clock signal to generate the display clock signal. The display clock signal is also locked to the reference clock signal.

The present invention relates to integrated circuits (ICs), and more particularly to video processor ICs adapted to provide matching rates between input and output video frames.
Incoming data received by a video processor typically has a different resolution than the data supplied by the video processor, thereby requiring format conversion. For example, incoming data frames may have a resolution of 680*480 pixels per frame, whereas the output frames may require, for example, a frame resolution of 1280*1024 pixels. In conventional systems, to attempt to match the input and output frame rates, a combination of display clock frequency, display width and display height is determined by trial and error. Pixels might be added to or subtracted from either the horizontal width or vertical height of the output frame while the output clock frequency is varied in small steps. In general, a group of such settings is predetermined to handle different combinations of input and display frame rates that a system is expected to encounter. Accordingly, in conventional systems, the matching of the input/output frame rates is approximate and susceptible to inaccuracies such as input signal deviation from standard specifications or circuit component variations. Furthermore, such matching is not automatic.

Locking display pixel clock to input frame rate


A storage node electrode formed of doped amorphous silicon is provided on a silicon substrate. Silicon crystal grains are formed on the surface of the storage node electrode by annealing it in the atmosphere including PH.sub.3. A capacitor insulating film and a cell plate electrode are formed to cover the surface of the storage node electrode including silicon crystal grains. Larger silicon crystal grains are accordingly provided on the surface of the storage node electrode, resulting in increased capacitance of the capacitor.

1. Field of the Invention
The present invention generally relates to a semiconductor memory device, and more particularly, to a semiconductor memory device improved such that it has increased capacitance of a capacitor. The present invention also relates to a method of manufacturing such a semiconductor memory device.
2. Description of the Background Art
Three dimensional structure is essential to the capacitor of Dynamic Random Access Memory (DRAM) due to the reduction of its cell size. Various capacitor structures have been proposed. For example, the capacitor structures such as fin type and crown type are known. One proposed method of increasing the surface area of a capacitor electrode (storage node electrode) formed of polysilicon is to form concave and convex parts on the surface. The polysilicon thus obtained is called rugged polysilicon for its surface structure.
A method of manufacturing a semiconductor memory device having a capacitor of the rugged polysilicon is disclosed, for example, in Applied Physics, Vol. 61, No. 11, p.p. 1147-1151. The method will be hereinafter described with reference to appended figures.
Referring to FIG. 10, an interlayer insulating film 2, is formed on a silicon substrate 1. A contact hole 2a for exposing the surface of silicon substrate 1 is provided in interlayer insulating film 2.
Referring to FIG. 11, an amorphous silicon 3 doped with phosphorus is formed on silicon substrate 1 such that it fills contact hole 2a. Doping of phosphorus is for the purpose of making amorphous silicon 3 conductive.
With reference to FIGS. 11 and 12, doped amorphous silicon 3 is patterned to form a storage node electrode 4.
With reference to FIGS. 12 and 13, by annealing storage node 4 in disilane atmosphere, silicon crystal grains 4a are formed on its surface, producing storage node electrode 4 with concave and convex portions on its surface. Silicon crystal grains 4a are derived from amorphous silicon, grown into crystal by annealing. Although not shown in figures, a capacitor insulating film is then formed on the surface of storage node electrode 4, and a cell plate electrode is further formed thereon to complete a semiconductor memory device.
The outer surface area of the storage node electrode 4 is increased because concave and concave portions are formed thereon, resulting in an increased capacitance of the capacitor.
Using the conventional method of forming rugged polysilicon described above, however, a storage node electrode with sufficiently large surface area could not be obtained.

Method of manufacturing semiconductor memory device