text:
|Publication number
|Publication type
|Application number
|Publication date
|Mar 30, 2004
|Filing date
|Apr 13, 2001
|Priority date
|Nov 9, 2000
|Fee status
|Also published as
|Publication number
|Rolf Dieter Schraft, Andrea Hiller, Jochen Klenk, Joachim-Gerd Rein, Alexander Paul Horke
|Original Assignee
|Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung, E.V.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (14), Referenced by (14), Classifications (26), Legal Events (8)
|External Links: USPTO, USPTO Assignment, Espacenet
This application is Continuation-in-Part of application Ser. No. 09/747,628, file May 25, 2001, pending.
The present invention refers to a device and a procedure for joining hollow organs. With devices and procedures of this kind for attaching blood vessels, the suturing process, for example, can be mechanized and consequently speeded up and simplified. This is of great importance in coronary surgery, in particular for performing operations on the beating heart. Furthermore, through the use of devices and procedures of this kind a repeatable and high-quality suturing process can be carried out, so that the risk of the vessels not being leak-free is minimized or, for example, in coronary surgery that the rear wall of the blood vessel in question is also attached.
An important area of application for devices and procedures of this kind is the suturing of end-to-side anastomoses in coronary by-pass surgery, i.e. surgically applied unions of hollow organs in which one end of a vessel is sewn laterally to another one. The devices and procedures under the invention can, however, be used for sewing vessels in all other areas of vascular surgery.
Today, about 70,000 by-pass operations are performed each year in Germany alone. Anastomoses on the coronary arteries are the most difficult discipline. They require a great deal of skill and experience on the part of the surgeon, because the blood vessels here are extremely small, with an average arterial diameter of 2 mm and an average vascular diameter of 4 mm, and where the diameter of the other transplants, arteria mammaria interna, for example, is often only 2 mm. In particular, there cannot be any leakage or attachment of the rear wall of the vessel.
The manual procedure can be divided up into the following operational steps, where the attachment at the anastomosis suture represents the task which can be taken over by mechanical devices and the appropriate procedures. First of all, a thoracotomy and a sternotomy (opening and separation of the chest wall) are performed. Parallel to this, the transplant (e.g. vein) is obtained and prepared for attachment to the artery with a suitable diagonal end cut. In the next step, an incision is made into the artery as a lengthwise opening. Next the openings of the vein and the artery are joined to each other. This can be simplified and improved by means of a mechanical device. Finally, the thorax is closed up again.
Under the present art, several types of what are called staplers are currently known, which, like a paper stapler, place a clip instead of a suture. The systems are used primarily for larger vessels or for sealing off open vessels. Leaks in particular are a major problem with end-to-side staplers. Staplers of this kind are known, for example, from U.S. Pat. Nos. 5,732,872, 4,930,674 or 5,285,945.
Coupling systems, such as those described in "Review of Facilitated Approaches to Vascular Anastomosis Surgery," Werker, P. et al., The Society of Thoracic Surgeons, 1997, follow another approach to joining vessels. Coupling systems of this kind are used mostly in the intestine, or to join the blood vessels end-to-end.
A third group of procedures for connecting vessels is based on the conventional suturing technique, which has been mechanized. A system of this kind, for example, is the ArthroSew™ Suturing System from U.S. Surgical Dynamics.
The disadvantage of all these systems known from the present art is that they often do not provide any possibility for end-to-side anastomosis, or are not suitable for small vessels with a diameter of about 2 mm. In particular, they are often also not suitable for by-pass surgery.
Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.
It is, therefore, the object of the present invention to make available a procedure and a device for closing an opening in a blood vessel or for joining hollow organs, in particular for performing anastomoses, with which two hollow organs can be joined in a way that is simple, safe and of high quality, as well as being repeatable.
This task is solved by means of the device in accordance with the invention.
With the device according to the invention or the procedure according to the invention, both proximal as well as distal anastomoses can be performed in a coronary artery bypass operation (CABG), as well as anastomoses with the arteria mammaria interna as the transplant. In addition, they can be employed for closing (sewing up) a blood vessel.
The fundamental operating principle of the device under the invention and the procedure under the invention is based on simultaneously punching several needles with sutures through a vessel, where there are similar needles at the other end of the suture, which are simultaneously punched through a second vessel. By pulling the ends of the two sutures tight, placing the ends of the sutures in the cradle and tying the ends of the sutures together, the two vessels are then securely attached to each other.
This conception of the device and the procedure solves the task of joining hollow organs, specifically performing anastomoses in a simple, safe and repeatable way. The primary field of application is by-pass surgery on the heart with coronary ischemia, but in addition operations on other organs in the case of stenoses, occlusions, strictures and thromboses, for example, in peripheral arteries.
In contrast to manual attachment or the conventional procedures, there is no risk of the rear wall of the vessel being attached or the anastomosis suffering from leakage. With the device under the invention and the procedure under the invention, most operations can not only be performed on the asystolic heart, so that any additional traumatization for the patient as the result of the use of the heart-lung machine is avoided. Specifically, the attachment of very small vessels with a diameter of about 2 mm is possible in safety.
On the basis of the mechanized suturing process, the quality of the suture is improved, the rear wall is protected, for example, by means of a needle carrier designed as a shoe, and the operation can consequently be carried out in most cases on the beating heart.
Under the invention, the device for joining hollow organs has several elements, which are an elongated holder a needle carrier, which is located at one end of the holder, where the needle carrier forming a projecting overhang extends radially beyond the elongated holder, so that a plurality of needles can be disposed in a ring on this projection pointing away from the end of the holder, for example, so that they stand vertical, while their ends are connected to sutures. In this way, the needle carrier is constructed as a shoe, which protects the rear wall of the vessel from the needles when the holder is inserted into the incision in the vessel. The needles can then be splayed out at a predetermined angle and, with the assistance of a needle seat positioned on the outside of the vessel wall, pushed through the vessel wall along the circumference of the incision.
If the other side of the sutures is connected with needles in a similar carrier, the second vessel which is to be connected to the first one can be sutured in this way along the periphery of its incision, so that the two openings are joined along their circumference when the sutures are subsequently pulled tight and tied together. With this, both hollow organs are securely joined together with their openings flush and in a sealing manner.
The holder can be implemented as a table stand, for example, for the end of a transplant, if the transplant is still unattached, or as a handle for example, for the second end of the transplant or for the mammaria. In addition, the holder can be equipped with an insertion aid for the transplant, for example, the vessel undergoing anastomosis. This insertion aid can be an enlargement of the elongated holder, or be mounted in the elongated holder in such a way that after the transplant is pulled over the holder and the insertion aid, this insertion aid is expanded so that the transplant has a larger circumference. In this way the transplant can be expanded to a circumference which extends beyond the periphery of the array of needles, so that by means of axial movement in the direction of the holder, the needles can be then pushed through the vessel wall of the transplant.
Instead of being pulled over an insertion aid, the holder can also be connected to a sleeve, for example, a cylindrical hollow body. The sleeve can be furnished with a suction device. When the transplant is inserted/introduced into the sleeve, its outer wall is pulled against the inner wall of the sleeve by suction and held in position there.
In the next step the end of the transplant is cut to shape. To do this, the sleeve can have a cutting surface which is a surface not oriented parallel to the direction of its internal passage, for example perpendicular or diagonally at a predetermined angle.
Set off from this cutting surface, the sleeve has adjustable pressure pads along its circumference by means of which the transplant can be squeezed together. Then the transplant has a larger cross section in the area of the cutting surface than in the area of the pressure pads and it narrows down in the transition to the area of the pressure pads, for example, like a funnel.
If the diameter of the needle array is selected in such a way that it lies between the diameter of the two cross sections, the needles can be moved in the direction of the transplant in the axial direction of the sleeve, starting from the inside of the transplant, until they push through the wall of the transplant in the funnel-shaped area and they can be located on the outside of the transplant by a needle seat.
Since only the outside of the transplant is touching the inside of the sleeve, the endothelial layers on the inside of the transplant cannot be damaged. Consequently, both distal as well as proximal anastomoses can be performed, as well as anastomoses with the mammaria.
With respect to the artery also, it can be held by annular suction by means of a suction device before the incision is made. Kept in position like this, the incision is then made inside the suction-held area at a length matching the circumference of the transplant, and then the shoe with the needles is inserted, without the possibility that the arterial walls could collapse into the artery after performing the incision.
To protect the needles when they are being inserted, or rather to protect the vessel from the needles, a needle cap can be pulled over the needles and the needle tips, which is removed from the needles immediately before the needles are deployed, or before the needles are pushed through the vessel wall. In this way, the vessel is protected for as long as possible from the sharp-pointed needles and injuries resulting from them.
The needles can be extended in the direction of the lateral vessel wall immediately before being pushed through the vessel wall, while a sleeve is inserted between the needles and the elongated holder and the needles are splayed outwards.
All the movements of the needle cap or the sleeve, for example, or the two-part seat for pushing the needles through the vessel wall, can be carried out by simply pressing buttons, for example by using a handle which is attached to the holder and has the appropriate controls with mechanical means of movement.
Once the two openings of the vessels are sutured and the sutures drawn tight, the needle seats with the needles and the sutures attached to them can be placed in a cradle, where as the result of proper design of the cradle and proper placement of the needle seats, the sutures coming from the transplant or from the artery are correctly sorted out automatically. The matching ends of the sutures can then be tied together correctly.
Tying the sutures together can be done, for example, by means of an auxiliary instrument which takes up the parallel sutures in the cradle from the two sides (artery, transplant) and encloses them with clips. The auxiliary instrument can be designed in such a way that several clips can be placed simultaneously, or only one clip is placed at a time. If several clips are placed simultaneously, it is advantageous if the end effector of the auxiliary instrument is designed in such a way that the distance between the clips on the auxiliary instrument is equal to the distance between the sutures in the cradle.
As an alternative to the auxiliary instrument, conventional knots can continue to be made or other procedures such as bonding, thermal forming, etc. can continue to be used. In addition, clips made of nitinol, such as those produced by the Coalescent Surgical Co. Inc., can be used to join the sutures coming from the two hollow organs.
In addition to straight needles, curved needles are also conceivable.
For sewing on a arteria mammaria interna (an artery which is already on the heart and is only being sutured unilaterally), it is conceivable to design the instrument as a minimally invasive surgical instrument and to introduce it into the body through small incisions and to suture without opening the sternum. To do this, the part of the instrument for the artery and the transplant side would be introduced into the body by means of a trocar and handled endoscopically.
The handles of the tool can also be designed in such a way that they can be manipulated by a robot. In the first step, the procedure for the transplant could continue to be performed by hand and only the procedure for the artery be carried out by the robot. To do this, a flange, which is attached to a robot flange, would be installed for the artery side instead of the hand grip. The movement of the needle cap, the sleeve and the two-part seat are then controlled electrically, hydraulically or pneumatically or by other drives.
The transplant portion can also be handled by a second robot arm for the suturing of the arteria mammaria interna. The handle with the needle carrier and the insertion aid would be flanged to a robot. The two-part seat would need to be pushed up manually or by yet another robot arm and pulled out along with the needles. The needle seat (two-part seat) is then put into the cradle by the robot, and the tightening and tying together is done manually.
Other applications of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.
The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
In what follows some examples are given of devices and procedures under the invention.
FIGS. 1a-c show an anastomosis being performed;
FIGS. 2a-c show a device under the invention;
FIG. 3 shows an artery with a needle carrier inserted;
FIG. 4 shows a needle carrier inserted with needle cap raised;
FIG. 5 shows the arrangement according to FIG. 4 in cross section;
FIG. 6 shows a cross section through an artery with a needle carrier inserted, penetrating the vessel wall;
FIG. 7 shows an artery with a vessel wall sutured;
FIG. 8 shows another device under the invention;
FIG. 9 shows the device from FIG. 8 with the vessel expanded;
FIG. 10 shows the device according to FIG. 9 with the vein pulled down over it;
FIG. 11 shows the device according to FIG. 10 with the needle seat;
FIG. 12 shows the device according to FIG. 11 with a sutured vessel wall;
FIG. 13 shows the device according to FIG. 12 with the needle seat removed;
FIGS. 14a-d show a set under the invention;
FIG. 15 shows the schematic of a set under the invention during suturing of a vessel;
FIG. 16 shows the set according to FIG. 15 with the needle seats removed;]
FIG. 17 shows a needle seat cradle;
FIG. 18 shows a section of the needle seat cradle from FIG. 17 with the needle seat in place;
FIG. 19 shows the cradle according to FIG. 18 with two needle seats in place;
FIG. 20 shows the cradle according to FIG. 19 with needle seats placed one over the other;
FIGS. 21a-b show a device for clipping the ends of sutures;
FIG. 22 shows another device for clipping sutures;
FIGS. 23a-c show an additional device in accordance with the invention;
FIGS. 24a-c show an additional set in accordance with the invention;
FIG. 25 shows the schematic of the set from FIG. 24 while the blood vessels are being sutured;
FIG. 26 shows an additional schematic of the set from
FIG. 24 while the blood vessels are being sutured and
FIGS. 27a-c show the sequence when suturing the transplant with a device in accordance with FIG. 23.
FIG. 1 shows schematically the attachment of end-to-end anastomoses. FIG. 1A shows an artery 10 and a vein 11. The vein 11 is a transplant which is to be joined to the artery 10. Here, as in all the following illustrations, similar components are identified with similar reference numbers. In FIG. 1B an incision 12 has been made in the artery 10. The end of the vein 11 has been cut on the diagonal so that a suitable opening 13 results, whose diameter approximately matches the diameter of the opening 12. FIG. 1C shows how the two openings 12 and 13 of artery 10 and vein 11 are joined to each other and sutured, so that now an end-to-end anastomosis has been performed.
FIG. 2 shows a device under the invention, which can be used when creating anastomoses shown in FIG. 1. This device has a handle 1, at the end of which a shoe 2 is formed as a needle carrier for needles. This shoe 2, along with the needles disposed vertically on it, is covered by a needle cap 9. Above the needle cap 9 there is a needle seat 3, whose function will be explained later. In addition, sections of sutures 4 are shown, which are connected to the ends of the needles.
FIG. 2B shows the lower part of the device from FIG. 2C in an enlarged view in a lateral cross section. Again, the shoe 2 can be seen, on which needles 7 are standing vertically in a ring around a holder 20. These needles 7 are connected to sutures 4 by the ends facing the shoe 2. Above the points of the needles there is a sleeve 8, which can be moved along the holder 20 by means of a sleeve linkage 23. The entire arrangement of needles 7 and sleeve 8 is covered by a needle cap 9, which can similarly be moved along the holder 20 by means of a linkage 21, and in its lowered position provides a protective covering for the needles 7 and the sleeve 8. Above this protective cover 9 there is needle seat 3, which can similarly be moved along the holder 20 by a suitable mechanism which is not shown here.
FIG. 2A now shows in a cross section rotated by 90� to FIG. 2B a needle carrier 2, which is inserted into an artery 10. The needle carrier or shoe 2 was inserted into the artery 10 through a suitable incision not shown in the cross section and then, as shown in FIG. 2A, the needle cap 9 was raised. As a result, the needle points are now exposed inside the artery, but the rear wall of the artery is protected from the needles 7 by the shoe 2.
Both the sleeve 8 and the needle cap 9 can be moved up or down by means of their corresponding linkages 23 or 21 through push buttons 5 or 6 on the handle 1, as shown in FIG. 2C.
FIG. 3 shows the same arrangement as in FIG. 2B, however in an external view of the artery 10. It can be seen clearly here that the needle seat 3 can be separated into two, where the needle seat 3 can be moved along the holder rod 20 by means of the linkage 22.
FIG. 4 shows a similar view as in FIG. 3, where however the position of the individual parts corresponds to that in FIG. 2A, i.e. the needle cap 9 has been pulled off the shoe 2 out of the opening in the artery 10 by means of its linkage 21.
FIG. 5 shows the next step during the performance of the anastomosis, where the sleeve 8 has been pushed between the needles and the holder linkage 20 by means of its linkage, so that the needles are now standing sideways at an angle and are spread out radially. If the shoe 2 is now pulled up, or the needle seat 3 is pushed down, the tips of the needles 7 are pressed through the wall of the artery 10 along the circumference of the incision and they come to a stop in the needle seat 3. This is shown in FIG. 6, where following this position, the needle seat 3 can be withdrawn upward or opened, and the two halves of the needle seat 3 a and 3 b can be withdrawn laterally.
This is shown in FIG. 7, where it is can be seen that the needles are being removed together with the halves of the needle seat 3 a and 3 b, where they are pulling the sutures, here 4 a and 4 b, which are attached to them, through the suture holes.
Not all the sutures which come from the ends of the needles are shown in FIG. 7 for the sake of clarity. But it must be made quite clear at this point that the end of each needle is provided with its own suture, which runs through the corresponding suture opening into the interior of the artery and then along the holder 20 and out of the incision.
With this step, the first half of performing an anastomosis is concluded. Next comes the suturing of the opening of the vessel to be attached, for example, of a vein.
FIG. 8 shows a suitable device, where, instead of a handle, a table stand 30 is being used, which has a center rod 31 as well as a needle carrier 32, in which needles 37 are disposed in a circle around the center rod 31. These needles 37 are connected at their ends to sutures 34. It should be noticed that matching the diagonal cut at the opening of the vein, as shown in FIG. 1, the needle carrier is beveled in the same way.
FIG. 9 shows the device from FIG. 8, where an installation aid or insertion aid 35, which is enlarged in one section, is mounted over the central rod 31. Alternatively, the insertion aid can be designed just to be dilatable, for example, by suitable inflation.
FIG. 10 shows another section from a device in accordance with FIGS. 8 and 9, where a vein 11 is now pulled over the insertion aid 35. The vein is now similarly greatly stretched in the enlarged section of the insertion aid, where the diameter of the vein in the stretched area is greater than the diameter of the needle arrangement with the needles 37. In FIG. 10 it can also be seen that one half 33 a of a two-part needle seat is placed on the vein above the enlarged area.
In FIG. 11 the needle seat 33 has been fully assembled from its two halves 33 a and 33 b.
In FIG. 12 it can be seen that the needles are now being pushed axially along the center rod 31, or the vein with the seat 33 is being pushed in the direction of the needles, so that the needle points pierce the vein wall from inside the vein and come to a stop in the seat 33.
FIG. 13 shows how the two parts of the needle seat 33 a and 33 b are pulled away upwards from the expanded part of the vein, whereby the sutures 34, which are attached to the ends of the needles 37, are pulled through the corresponding suture holes in the vein 11. This pulls the corresponding sutures through the opening 13 of the vein, so that the two openings 12 or 13 of artery 10 or vein 11 respectively can now be joined to each other.
For this, FIGS. 14A and 14B once more show a holder corresponding to FIG. 2 with a handle 1, and in FIG. 14B the overall arrangement of shoe 2 with needles and sutures 4 and the table stand 30 with needles 37 and sutures 34. As can be seen, the open ends of the sutures in both arrangements are attached to each other in each case. After the wall of both the artery and the vein have been pierced, the sutures 4 or 34 consequently run from outside the vein through a suture hole in the vein into the interior of the vein, from there into the interior of the artery and out again through a hole pierced in the wall of the artery.
FIG. 14C, and in a section from it FIG. 14D, show an alternative to the table stand 30. Here the needle holder 32 with the needles 37 is attached to a handle 40, where the handle ends in a tip over which the vein can be pulled in a suitable way. Installation aids or insertion aids, as described above, can be attached here.
FIG. 15 shows the drawing in FIG. 14B in enlarged form. The sutures are shown in two examples 4 a, 4 b or 34 a, 34 b respectively. Otherwise the drawings correspond to the illustrations in FIG. 4 or 12 respectively.
FIG. 16 shows the illustration with the divided seat 3 a, 3 b or 33 a, 33 b respectively pulled back, where again only two sutures 4 a, 34 a or 4 b, 34 b respectively are shown as examples. Otherwise the illustration in FIG. 16 corresponds to the illustrations from FIG. 7 and FIG. 13.
FIG. 17 shows a cradle 31 for the split needle seat from FIG. 16. This cradle 41 has slit-like openings 42, the distance between which matches the distance between the sutures which come from the divided seats 3 a, 3 b or 33 a, 33 b respectively.
FIG. 18 shows how one seat 33 b is placed into the cradle 41.
The slit-like openings 42 here are designated by the reference numbers 42 a through 42 e, where only suture 34 b which is running through slit 42 e, is given a reference number.
FIG. 19 shows how one half 3 b of a needle seat and one half 33 b of an additional needle seat are placed next to each other in the cradle 41.
In order to tie the ends of the respective sutures together correctly, the seat 33 b is laid in a suitable way over the seat 3 b (FIG. 20). As a result, the two ends of the same suture, shown for example as 4 b and 34 b, are automatically located in each of the slits 42.
The ends of the sutures can be clipped together by means of a auxiliary instrument. FIG. 21 shows such an instrument, where the entire instrument 45 with grip 46 and shaft 47 is shown in FIG. 21B, while FIG. 21A brings only the end of the shaft 47. A clip holder 48, which can hold up to five clips 49 is positioned at the end of the shaft 47. With the aid of these clips 49 the specific suture ends can be attached to each other.
FIG. 22 shows another auxiliary instrument 45, which, however, has a clip holder for only one clip 49. Instead, the instrument 45 from FIG. 22 has a tong-like anvil 50, so that two ends of the same suture can be clipped together in a simple fashion with this instrument 45.
It must be noted in the case of the procedures under the invention that before the ends of the sutures are clipped together the sutures from the artery side and the transplant side are pulled tight, so that the opening in the vein lies completely and in a sealing manner on the incision in the artery. Then the sutures can be clipped together in this tightly approximated position.
As an alternative to an auxiliary instrument, such as the one shown in FIGS. 20 and 21, the ends of the sutures can, of course, be knotted in the conventional manner or other procedures such as adhesive bonding, thermal forming and similar methods can be employed. Clips made of nitinol (Coalescent Surgical Co., Inc.) can also be used.
FIG. 23 shows a further embodiment for a device which corresponds to the one from FIG. 8. This device has a handle 40 to which a base 61 is attached. The base 61 acts as a holder for the needle carrier 32 in which needles 37 are disposed in an annular arrangement. A needle seat 62 is positioned in an axial direction to this annular arrangement 37, with passages which extend in the axial direction of the individual needles and through which the needles are passed during an axial movement of the needle array 37.
Another needle seat 33A and 33B is located adjacent to the seat 62, into which the needles are introduced with the axial movement. This seat 33 is a divided seat, which can be subsequently separated into two halves 33 a and 33 b and removed with the needles 37 sticking in them.
Both the seat 62 and the needle seat 33 are formed as hollow bodies with passages extending in the axial direction of the needle array 37.
The seat 62 and the needle seat 33 are attached to the base 61 by means of an external bar-shaped bracket 65.
As can be seen from FIGS. 23B and 23C, the seat 62 and the needle seat 33 are shaped in such a way that the cross-section of their passage can be made narrower. This can be achieved, for example, by creating air cushions. FIG. 23B shows how a transplant 11 is inserted into the passage of the seats 62 and 33. FIG. 23C shows how, by means of the pressure cushions the seats 33 and 62, the cross section of the passage and along with it the diameter of the transplant 11 is constricted locally, so that the cross section of the transplant remains unchanged only at the surface of the seat 62. The transplant narrows down consequently starting from this surface 67 in a funnel shape in the axial direction of the needles 37. The largest diameter of the passage of the seat 62 is now adjusted so that it is larger than the diameter of the ring of the needle array 37. The constriction by means of the pressure cushions in the seats 33 and 62 continues down to a diameter that is smaller than the diameter of the needle array 37. This creates a transition zone for the transplant in which the transplant tapers down in a funnel shape. If the needles are now punched through the transplant in an axial direction, they penetrate the transplant in the expanded area along the edge of the incision 67 and are pushed through the transplant in the funnel-shaped area 70.
It is advantageous if the seat 62 and/or the needle seat 33 are furnished with a device to apply a vacuum to the inner surface of their passage. In this case the transplant 11 can have suction applied on its outside and be held in position in this way. By holding the transplant in position by means of suction applied to the outside, damage to the inside of the transplant, particularly the endothelium, is avoided.
FIG. 24 shows the set up of the device for suturing the transplant and the artery.
The needles in both devices are connected to each other by means of sutures 34, where, just as in FIG. 14, only a part of the sutures is shown. For a further explanation, reference is made to the appropriate FIG. 14, where only the device shown there for suturing the transplant has been replaced by the device from FIG. 23 for suturing the transplant.
FIG. 25 shows this arrangement of the two devices according to the invention, the ends of whose needles are connected in each instance by sutures 4A, 34 a or 4B, 34 b.
FIG. 26 shows the same arrangement after the needles 7 or 37 have been pulled through the artery 10 or the transplant 11. The needles 7 or 37 are then pushed into the needle seats 3 or 33 respectively and held in position there. The needle seats are now separated into two needle seat halves 3 a, 3 b or 33 a and 33 b respectively and removed with forceps 69 whose ends are adapted to the seat. Then the needle seats 3 a, 3 b, 33 a, 33 b can be set down in suitable seat cradles, and by pulling the sutures tight the transplant can be attached to the artery and thus sutured to it.
FIG. 27 shows in the subillustrations A through I the exact sequence of suturing the transplant. Here a device in accordance with FIG. 23 is used, where the same reference numerals are used for the same elements. FIG. 27A shows the device immediately prior to the suturing process. FIG. 27B shows how the transplant 11 is introduced into the needle seat 33 and the seat 62. FIG. 27C shows the transplant being held by suction against the inner walls of the passage of seats 33 and 62. In step 27D the transplant is cut off using a knife 66 along the diagonal surface 67 of the seat 62, so that it already has a diagonal aspect which matches the opening in the artery to which the transplant is to be sutured. In FIG. 27E the transplant 11 is being constricted behind its opening and the cutting surface 67 by means of pressure pads in the seats 33 and 62.
FIG. 27F shows how the needle array 37 is now displaced in an axial direction and thereby the individual needles 37 are pushed through the transplant 11 from the inside to the outside in the funnel-shaped constricted area.
FIG. 27G shows how, after the needles have been passed through the transplant, the needle seat 37 is withdrawn in an axial direction over the transplant and is then separated, and the two parts of the seat 33 a and 33 b are removed from the transplant.
FIG. 27H shows a cradle 41 for the needle seats 33 a and 33 b, while FIG. 27I shows how the needle seat 33 b is placed in the cradle in such a way that one suture 34 is deposited in each of the slits 42 of the cradle 41.
The remainder of the process of attachment is performed as described in the previous examples.
In a further example, the instruments and devices presented could be designed as minimally invasive surgical instruments, so that it is not necessary to open the chest wall and the instrument is introduced into the body through small incisions, for example using a trocar.
In additional examples the handles 1 can also be designed in such a way that they can be manipulated by a robot. In this way, extensive automation of the suturing procedure would be possible.
In summary, it can be said that through the device under the invention, or through sets under the invention having two or more of such devices, at least one in each case for the artery side and one for the vein side, it is possible to join hollow organs together in a simple and safe manner.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.
|Cited Patent
|Filing date
|Publication date
|Feb 24, 1989
|Jun 5, 1990
|Abiomed, Inc.
|Surgical stapler
|Dec 30, 1992
|Feb 15, 1994
|Ethicon, Inc.
|Surgical anastomosis stapling instrument
|Nov 10, 1992
|Jun 14, 1994
|Harald Heidmueller
|Surgical suturing apparatus
|Mar 21, 1994
|Apr 4, 1995
|United States Surgical Corporation
|Instrument for closing trocar puncture wounds
|Dec 2, 1994
|Sep 10, 1996
|Delange; Gregory S.
|Method and device for surgically joining luminal structures
|May 3, 1995
|May 6, 1997
|Lasersurge, Inc.
|Trocar wound closure device
|Feb 6, 1996
|Mar 31, 1998
|Heartport, Inc.
|Surgical stapling instrument
|Jun 14, 1994
|Jul 14, 1998
|Perclose, Inc.
|Device and method for the percutaneous suturing of a vascular puncture site
|Jun 26, 1997
|Oct 12, 1999
|Automated Medical Products, Inc.
|Laparascopic suturing device and suture needles
|Sep 14, 1999
|Mar 19, 2002
|Abbott Laboratories
|Device and method for performing end-to-side anastomosis
|Nov 20, 2001
|Jun 20, 2002
|Arcia Rovil P.
|Device and method for performing end-to-side anastomosis
|Title not available
|Feb 16, 1999
|Aug 19, 1999
|Heartport, Inc.
|Devices and methods for performing vascular anastomosis
|Mar 31, 2000
|Oct 12, 2000
|Bjerken David B
|Vacuum-assisted remote suture placement system
|Citing Patent
|Filing date
|Publication date
|Nov 18, 2005
|Dec 2, 2008
|Cardica, Inc.
|Vascular closure system utilizing a staple
|Jan 11, 2008
|Jun 1, 2010
|Cardica, Inc.
|Method for closing an opening in tissue with a splayable staple
|Jun 29, 2010
|Cardica, Inc.
|System for closing a tissue structure from inside
|Sep 14, 2010
|Cardica, Inc.
|Compliant anastomosis system
|Dec 3, 2004
|Nov 5, 2013
|Cardica, Inc.
|Compliant anastomosis system utilizing suture
|Jun 7, 2013
|Oct 6, 2015
|P Tech, Llc
|Robotic system for engaging a fastener with body tissue
|Mar 20, 2002
|Oct 13, 2015
|P Tech, Llc
|Robotic systems and methods
|May 7, 2013
|Nov 24, 2015
|P Tech, Llc
|Robotic fastening system
|Aug 8, 2013
|Mar 1, 2016
|P Tech, Llc
|Robotic ultrasonic energy system
|Aug 13, 2013
|Mar 1, 2016
|P Tech, Llc
|Methods of using a robotic spine system
|Jul 20, 2007
|Jan 24, 2008
|Cardica, Inc.
|System for Closing a Tissue Structure from Inside
|Jan 11, 2008
|May 15, 2008
|Cardica, Inc.
|Method for Closing an Opening in Tissue With a Splayable Staple
|May 25, 2006
|Aug 21, 2008
|Texas Heart Institute
|Surgical System and Method For Attaching a Prosthetic Vessel to a Hollow Structure
|May 7, 2013
|Oct 17, 2013
|P Tech, Llc
|Robotic fastening system
|U.S. Classification
|606/144, 606/153
|International Classification
|Cooperative Classification
|European Classification
|Dec 31, 2001
Owner name: FRAUNHOFER-GESELLSCHAFT ZUR FORDERUNG DER ANGEWAND
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Owner name: IP VERWERTUNGS GMBH, GERMANY
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FRAUNHOFER-GESELLSCHAFT ZUR FORDERUNG DER ANGEWANDTEN FORSCHUNG E.V.;REEL/FRAME:022928/0417
Effective date: 20090617
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Effective date: 20120330


text:
"Building and Strengthening our Community Through the Arts!"
The Rosemount Area Arts Council
About Us
Upcoming Events
Get Involved
Art Classes
Senior Theater
Art Blast 2016
Website Designed
Create a Website
List Your Business
The One Tile One Rosemount Community Art Project is now on display in the Robert Trail Library! Find your tile on the art piece by going to the Information Desk in the library and requesting the directory.
Welcome to the Rosemount Area Arts Council website! Now that we've met, or if you're an old friend, please call us RAAC...as you may know, we were established in 2007 as a non-profit with a shared passion and mission:
"Building and Strengthening our Community Through the Arts."
RAAC is committed to bringing a broad spectrum of Arts to the community.We want to foster that "front-porch" mentality that we feel is important in a thriving community.
Navigation for our site is above, if you're curious about upcoming events, please click on
"Upcoming Events"
above, or certainly
"Like" us on Facebook!
As a passionate and dedicated group, we are always looking for new members. Click on "Get Involved" above to learn more. Even a donation to keep most of our events free would be most appreciated! Please look around and I bet you'll find an upcoming event that you'll want to put on your calendar…we look forward to seeing you!
Click on the image to learn about our Senior Theater and Upcoming Classes!
Click on the Links Below to Read our Newsletters!
April 2016 Newsletter
March 2016 Newsletter
February 2016 Newsletter
January 2016 Newsletter
Interested in being on the mailing list? Email firstname.lastname@example.com

subset: commoncrawl


text:
I have Windows server 2008 r2 64bit configured as a DC, Exchange 2007, Antivirus server and a DFS replication partner to the US over a sonicwall vpn connection (small office for 5 people, so everything on 1 server to cut costs).
I tried downloading wsus 3.0 and running the installer, it gets to halfway and then fails, gives an error about internal database - the microsoft help resolver mentions trying to download wyukon sp2, which I tried but still no luck. I've also tried installing the microsoft 2005 report viewer redistributable, but no luck.
Tried uninstalling wsus, rebooting and re-install, but still it fails. I then tried installing wsus as a server role, the installation works, but when I go to open the wsus admin console I get an error about not being able to connect to the wsus server (just a blank admin console, with a copy error to clipboard message).
All installations are using the default options, I've installed wsus on 2003 and 2008 previously without any problems.
Has anyone come across this before?
I know what Microsoft's official answer is, but do you think we're attempting to run too many services on the same server?
Any advice appreciated


text:
The Foxy Fall Century metric was listed as a 60.8 mile ride. However, the actual miles on my bike was 70.65.
Now that would seem to be much of a problem but the buzzards who like to fly low can figure their efforts pretty well to the length of the course and if you tell them it's 60 miles and it's really 70 they burn out at 61 miles.
Which is what happened to me. Well, not TO me but to someone else that did me in.
I was with a group that likes to ride as fast as they can for the distance which turned out to be very often above 20 mph. At first that's fun but it loses its luster pretty rapidly when you start getting close to 50 miles. I could tell that something was up with the guy really pushing the pace because he was starting to look for reasons to stop instead of just slowing down. Finally we approached a RR track in the last 10 miles and just as we arrived the signals turned on and the guy happened to be leading stopped cold.
I could see the train was still a quarter of a mile down the track and the other way was clear so I just continued on. So my group was stopped at what turned out to be a long train while I was riding at 20+ away from them.
Finally I came to the turn that signaled about 3 miles left to ride. I was passing everyone and a guy hopped on my wheel. As we got back on the UC campus there was a car stopped in the left hand lane a little short of the left turn where I needed to go. I slowed a bit and the guy on my wheel went from the left lane over in the the bike lane. I pulled over enough to pass the car and he started moving cutting me off from that lane. As I looked up the guy who passed me was making a left turn from the bike lane in front of both me and the car!
I t-boned him I think. And I was going maybe 17 or more at the time. I must have gone down on TOP of him. I had some real pain in my right side up near my armpit. But other than that I don't even have ROAD RASH! That's the first road fall I've had that didn't have road rash as an integral part.
No damage to my bike except the derailleur hanger was bent slightly out of alignment. Already fixed that.
He was busy making his getaway while I was really hurting in the street. I saw a taco'd wheel on his Colnago Master UltraLight and he was limping pretty good. I don't think he liked the comments I made at 120 dB.
I hope he's OK and didn't damage that beautiful bike. He made a dumb move but all's well that end's well.
The moral of the story is to keep your eyes open and don't do something wrong because you're tired and assuming that the car and therefore the guy next to him are all going to turn left.
I'll have some pain and probably some pithy comments for a couple of days but in the end I'll be out riding on my regular Tuesday ride. Well, I think I will.


text:
Good Technology for Disabled People-And Getting It Used-Is the Idea at the Phoenix Public Library Special Needs Center
Roatch, Mary A., American Libraries
Good technology for disabled people--and getting it used--is the idea at the Phoenix Public Library Special Needs Center
A PUBLIC LIBRARY, WHICH EXISTS FOR everyone, should be accessible to everyone. In Phoenix, with the help of technology, it is. Our Special Needs Center was developed to make the library available to handicapped people, their families, and the agencies serving them. Our high-tech aids supplement such basic resources as periodicals, newspapers, large-type books, circulating toys, braille, audio tapes, and videocassettes.
Computers and other new technology can help equalize learning opportunity for handicapped people. For example, synthetic speech and the "artificial intelligence' of the Kurzweil Reading Machine have made most of the library's books instantly available to blind users. A book is placed on the machine, an optical scanner photographs the print, and the information is sent to a computer unit to be read in a synthetic voice. The reading machine--combined with a VersaBraille paperless braille computer, Apple Ile computer with Echo II synthetic speech, and a letter-quality Diablo Printer--enables a blind person to read and write braille or printed material electronically, edit manuscripts, and print out corrected copies. The full circle is completed when the new copy is placed on the Kurzweil and the blind person can hear the revised text. Now that individual can read and write without dependence on a sighted person.
The Center's computer software programs include several word processing programs for blind users, such as Braille-Edit, Documents, Directories, and Textalker. There is also a Braille Fingerspelling program, and education software with synthetic speech. Other technological aids at the Center include a TDD (telephone device for the deaf), video print enlarger, and a microfiche enlarger.
Using these machines has been an exciting venture for both staff and disabled patrons. Our blind library users have ranged from four to 80. …


text:
Talk To Me Classic
по: Flaviu Negrean | 3.8K
Все Android приложения категории
по: Flaviu Negrean | 3.8K
Real-time speech to speech translator for Android.
Some languages were removed due to incompatibility with the new translation API. The old translation API was deprecated and is no longer available.
- compatible with SVOX high quality voices
- speech recognition in 15 languages
- output voices in multiple languages.
- home screen widget
- translation can be sent as SMS (text only) and email (text and voice)
- compatible with Android 1.6 and above.
Android 2.2 and above : Read app Help if you have problems with speech output.
Android 1.6-2.1: Update TTSExtended to the latest version available in the Android Market.
This application does not work on all devices. There are some known problems on certain devices and we are working hard to make the application work on all devices.
Uncheck "Always use my settings" from phone's TTS Settings
Uncheck "Override App Settings" in TTS Extended (Android 1.6 to 2.1)
Tags: talk to me classic , me clasic , telk to me classic , talk to me apk
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на основании 3.752 обзоров
Загрузить Talk To Me Classic
Бесплатные - V2.2 - 904K
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text: Hello friends, just wanted to know that Lenovo new ThinkPad T430u will be having Nvidia Geforce 610M graphics card on it or not? I was thinking to purchase this ultrabook, just wanted to make sure that it is having graphics card in it or not? If it is not having 610M then have Nvidia NVS 4200M? Is it having anyone of them, as I am searching for information but not getting any appropriate, so do tell me about it. Thank you.


text:
Police arrest 3 on drug chargesMarch 09,2013
BURLINGTON University of Vermont police have arrested three people from New York on suspicion of bringing about $70,000 worth of drugs by bus.
Police said they seized 1,400 bags of heroin, 1,000 oxycodone pills and 4 ounces of crack cocaine during the arrests this week of Shirley Colon, 21, and, Desean Nisbett, 21, both of the Bronx, and Sahirah Rasul, 17, of Brooklyn. More arrests are possible, police said.
UVM Police Capt. Tim Bilodeau said that campus, municipal and federal law enforcement have for months been aware of potential criminal activity where the Megabus docks at the universitys Davis Center, UVM Police Capt. Tim Bilodeau told the Burlington Free Press.
We were aware there was information in the police community that the buses had criminal activity around drugs. Weve specifically made our patrol aware of it for weeks now, he said Thursday.
Megabus.com/Coach USA spokesman Mike Alvich said his company had been notified of the drug investigation.
We cooperated 100 percent, and the authorities then moved in and made some arrests, he said.MORE IN This Just InWESTMINSTER Vermont State Police say a passenger has died in an off-road vehicle crash in... Full StoryPOMFRET More than 1,000 trees and shrubs have been planted along three rivers in New Hampshire... Full StoryWATERBURY Vermont State Police are investigating a weekend burglary at the Snowfire Auto... Full Story
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text:
|Numéro de publication
|Type de publication
|Numéro de demande
|Date de publication
|12 avr. 1994
|Date de dépôt
|9 avr. 1992
|Date de priorité
|9 avr. 1992
|État de paiement des frais
|Numéro de publication
|Alan H. Gnauck, Steven K. Korotky, Jane E. Zucker
|Cessionnaire d'origine
|At&T Bell Laboratories
|Exporter la citation
|BiBTeX, EndNote, RefMan
|Citations de brevets (4), Référencé par (107), Classifications (9), Événements juridiques (5)
|Liens externes: USPTO, Cession USPTO, Espacenet
This invention relates to lightwave communication systems and, more particularly, to modulation devices for use in such systems.
Long haul fiber transmission systems have historically been limited by such factors as fiber loss, fiber dispersion, fiber nonlinearities, and amplifier noise. With the advent of practical optical amplifiers, these systems are effectively no longer subject to loss limitations. Rather, the significant system limitation has become dispersion. Present fiber optic transmission systems use transmitters employing direct current modulation of laser diodes. When modulated, these lasers produce pulses exhibiting large, uncontrolled wavelength shifts called "chirp." In the presence of a dispersive medium such as an optical fiber, the chirped pulses can be severely distorted when they finally reach a remote receiver.
System limitations imposed by dispersion may be countered by the use of dispersion-shifted fiber, "zero-chirp" transmitters, dispersion equalization, and soliton propagation. The use of dispersion-shifted fiber attempts to minimize dispersive loss within the transmission band whereas the use of zero-chirp transmitters attempts to maintain the transmission wavelength constant, preferably at the attenuation loss minimum for the fiber. Dispersion equalization, both at the receiver and at the transmitter, has been utilized to substantially compensate for the effects of dispersion on the transmitted pulses. Soliton propagation is dependent upon the presence of small amounts of dispersion at the transmission wavelength.
In the prior art, zero-chirp transmitters have been developed to ameliorate the problem caused by chirped pulses transmitted at high bit-rates over dispersive optical fiber. Generally, the term chirped pulses refers to pulses those whose wavelength swings dynamically about a central wavelength. The amount of chirp varies randomly as the transmitter operates thereby causing the chirped pulses to incur penalties in such systems. These penalties involve additional loss which limits the maximum transmission length or maximum transmission bandwidth due to intersymbol interference in the transmitted data pulses. In conventional optical fiber, the wavelength at which the fiber loss minimum occurs does not necessarily coincide with the wavelength at which zero dispersion occurs. Thus, when the lightwave transmitter produces optical pulses at a particular wavelength corresponding to the loss minimum of the fiber, wavelength chirping of the pulses causes pulse spreading because different wavelength components of the pulses experience different amounts of dispersive delay. Dispersion is higher for wavelength components of the pulses not at the zero dispersion wavelength. By removing chirp from the transmitted pulses, it has been thought possible to produce pulses with the minimum spectral width substantially at a single desired wavelength using a zero-chirp transmitter and thereby assure that only a small amount of pulse spreading is experienced. In general, such zero-chirp transmitters include an external modulator coupled to a laser. One external modulator which has been proposed is a lithium niobate, Mach-Zehnder interferometer using push-pull drive signals on the separate arms of the interferometer. See, for example, Koyama et al., J. Lightwave Technol., Vol. 6, No. 1, pp. 87 et seq. (1988) and Namiki et al., Proc. of Seventh International Conf. on Integrated Optics and Optical Fiber Communication, paper 19D4-2 (1989).
While the zero-chirp transmitter offers a potentially attractive solution for high bit-rate transmission at a wavelength "in the" optical fiber exhibiting non-zero dispersion, better performance has been predicted by using pulse compression techniques in the transmitter to achieve a dynamically varying chirp in a broad negative region. See Koyama et al., J. Lightwave Technol., Vol. 6, No. 1, FIG. 8, p. 91 (1988). Subsequent to this prediction, however, the art continues to express the need for lowering the transmitter chirp to zero as the method for combatting dispersion when communicating away from the zero dispersion wavelength of the optical transmission fiber. See, Okiyama et al., J. Lightwave Technol., Vol. 6, No. 11, p. 1686, 1691 (1988).
External modulation of lightwave signals is controlled in order to minimize the transmission power penalty caused by chromatic dispersion in an optical fiber transmission system by adjusting a modulation chirp parameter to any substantially fixed value in a predetermined, controllable manner. External modulation is accomplished, for example, in a dual waveguide device wherein substantially identical input optical beams are supplied to the waveguides and wherein each waveguide is subject to its own individual, mutually exclusive control. Modulation signals are applied to each waveguide via the separate control. Moreover, control signals are applied to each waveguide for adjusting the modulation chirp parameter to a desired non-zero, substantially fixed value. Typically, the desired value of the chirp parameter is one which provides the lowest fiber dispersion penalty for the system. Modulated lightwave signals emerging from the waveguides are combined to form a single output signal suitable for transmission over an optical fiber.
In one embodiment, a Mach-Zehnder interferometer having separately controllable waveguides has its input coupled to a CW laser. Drive signals to the electrodes over each of the waveguides are generated to create a sufficient depth of modulation, a proper operating point for the modulator, and a desired value for the modulation chirp parameter. By using peak-to-peak voltage differences on each waveguide, it is possible to represent the value of the modulation chirp parameter as the sum divided by the difference of the individual peak-to-peak voltage differences. Both III-V semiconductor and Ti:LiNbO3 Mach-Zehnder interferometers have been realized.
A more complete understanding of the invention may be obtained by reading the following description of specific illustrative embodiments of the invention in conjunction with the appended drawing in which:
FIG. 1 shows a simplified lightwave transmission system including the transmitter realized in accordance with the principles of the present invention;
FIG. 2 shows a simplified schematic diagram for the controller in FIG. 1;
FIG. 3 shows a simplified perspective view of an exemplary external modulator for use in the system shown in FIG. 1;
FIGS. 4-7 show exemplary drive voltage waveforms and intensity waveforms for the controller and external modulator in FIGS. 1-3; and
FIGS. 8 and 9 show simplified perspective and cross-sectional diagrams of a semiconductor embodiment for the external modulator shown in FIG. 1.
Electrooptic external modulators for optical signals are known to operate with a very low amounts of chirp. In fact, Mach-Zehnder interferometer waveguide modulators have recently been designed to operate chirp-free. Chirp-free modulation has been thought desirable to overcome the transmission limitations imposed by fiber dispersion. However, it has been shown by us that the lowest fiber dispersion penalty is not necessarily obtained for a chirp parameter identically equal to zero. For example, we have shown this to be true for systems operated at 1.5 μm. using a fiber having a zero dispersion wavelength of approximately 1.3 μm. As described below, it is shown that choosing a non-zero modulation chirp parameter αm dependent on the fiber dispersion coefficient and fiber transmission distance is advantageous because of the pulse compression provided.
A lightwave transmission system is shown in FIG. 1 including a transmitter, a receiver, and a transmission medium connecting the transmitter to the receiver. The transmitter includes laser 10, lensed optical fiber 13, isolator 14, external modulator 16, controller 24, and data source 22. The transmission medium is shown as lengths of optical fiber 19 interconnected with optical amplifiers 20, so that the combinations of fibers and amplifiers are sufficient to span the distance between the transmitter and receiver 21.
In the lightwave transmitter shown in FIG. 1, laser 10 produces optical signals 12 at a predetermined transmission wavelength for the lightwave transmission system. Laser 10 is operated in a continuous wave (CW) mode or pulsed mode by applying the proper signal to terminal 11 of the laser. For long wavelength systems, laser 10 is typically an InGaAsP/InP semiconductor single mode laser operating nominally at 1.5 μm, for example. Output optical beam 12 from the laser is coupled into a lensed optical fiber 13 usually called a fiber pigtail. Lensed optical fiber 13 facilitates coupling of the optical beam from the laser to the external modulator.
Isolator 14 is positioned between lensed optical fiber 13 and the external modulator as an in-line element to reduce reflections toward the laser from the rest of transmission system. Isolator 14 can also be combined with a polarizer (not shown) to assist in further reduction of reflections back toward the laser. While isolator 14 is shown in the transmitter arrangement of FIG. 1, it should be noted that the isolator is an optional, rather than a necessary, element in the realization of the transmitter.
External modulator 16 receives optical signals 12 from the laser via input fiber 15. The external modulator includes two separate waveguides which are independently controllable via controller 24. At the input of the external modulator, optical signals from the laser are coupled into each of the waveguides labeled as waveguide A and waveguide B in FIG. 1. At the output of external modulator 16, the modulated optical signals from each waveguide are combined into a single optical signal for transmission over the optical fiber transmission medium. Modulation performed by modulator 16 on optical signals 12 is either amplitude modulation or intensity modulation.
Controller 24 receives a digital data signal from data source 22 via lead 23. Controller 24 generates modulation control signals output to external modulator 16 via leads 17 and 18. Modulation control signals from controller 24 are supplied via leads 17 and 18 to control characteristics of waveguides A and B, respectively, so that the data from data source 22 is properly modulated onto the optical signals at the transmission wavelength in the waveguides and so that the desired modulation chirp parameter value is generated in the resulting modulated optical signals. For example, the control signals can adjust the relative propagation velocities of each of the waveguides to permit the desired modulation chirp parameter value to be achieved in accordance with the principles of the invention.
The transmission medium includes a plurality of lengths of optical fiber together with optical amplifiers 20. Optical amplifiers 20 are, for example, erbium doped optical fiber amplifiers for amplifying the modulated optical signals as the propagate along the optical fibers 19. Optical fiber 19 is either a standard silica-based fiber having a loss minimum in the vicinity of 1.3 μm. or a dispersion shifted fiber having its loss minimum in the vicinity of 1.5 μm. The transmission medium is of sufficient length to span the distance from the transmitter to lightwave receiver 21.
Lasers, lensed fiber couplers, isolators, polarizers, data sources, externals modulators, optical fibers, optical amplifiers, and lightwave receivers are commercially available and well known to persons skilled in the art.
In an example from experimental practice, a waveguide Mach-Zehnder interferometer (FIG. 3) is used for external modulator 16 and an amplifier arrangement (FIG. 2) is utilized for controller 24. As shown in FIG. 2, exemplary controller 24 comprises gain-adjustable amplifiers 241 and 243 whose inputs are coupled together to receive the digital data on lead 23. Each amplifier can vary the peak-to-peak amplitude swing of the digital data at its output. Amplifier 241 is shown as an inverting amplifier. Such a function is not necessary to the practice of the invention. Moreover, phase control elements (not shown) such as adjustable delay lines are contemplated for use with one or both of the amplifiers, either preceding or following a particular amplifier. Such phase control elements permit the modulation control signal output on lead 17 to have a different phase relative to that of the modulation control signal on lead 18.
Exemplary external modulator 16 shown in FIG. 3 utilizes titanium in-diffused waveguides 162, 163, 164, and 170 in a 1×1 Y-branch Mach-Zehnder interferometer configuration on a lithium niobate substrate 161. Ground planes 165, 166, and 167 are disposed to maintain electrical isolation between drive electrodes 168 and 169 and to insure that the drive electrodes control their respective waveguides independent of each other. As a result, waveguides 164 and 163 are individually addressable via drive electrodes 168 and 169, respectively. The drive electrodes are of the travelling-wave or lumped-element type. Drive electrode 168 connected to lead 17 is disposed over a portion of waveguide 164 (waveguide "A") whereas drive electrode 169 connected to lead 18 is disposed over a portion of waveguide 163 (waveguide "B"). In the interferometer waveguide structure, an input Y-branch couples the optical signal in waveguide 162 into both coplanar strip waveguides 163 and 164 while output Y-branch couples the optical signals from coplanar strip waveguides 163 and 164 into a single waveguide 170.
Each optical waveguide is designed using standard techniques for single mode operation at the transmission wavelength (e.g., 1.5 μm). For the external modulator shown in FIG. 3, the waveguides were produced by diffusion of titanium z-cut LiNbO3 so that the two arms of the interferometer are separated by a distance of 250 μm, which is approximately 15 times the gap spacing used between the coplanar waveguide electrodes. The electrodes are formed using standard metallic plating techniques (e.g., gold plating). Although not shown, a silicon dioxide buffer layer is deposited or grown between the waveguides and the corresponding electrodes. Thicknesses of the buffer layer and electrodes, width of the electrodes, and size of the interelectrode gap are selected using standard techniques to realize a modulator having broad bandwidth and low V.sub.π, where V.sub.π is the voltage necessary to achieve a π-phase shift. For a discussion of design techniques for these types of devices, see Optical Fiber Telecommunications II, pp. 421-65 (S. Miller et al. ed. 1988) and S. K. Korotky, Technical Digest, Workship on Numerical Simulation and Analysis in Guided-Wave Optics and Optoelectronics, paper SF2 (1989). Impedance of the electrodes 168 and 169 has been measured as approximately 43Ω where the active length of the electrode is approximately 4 cm. An end-to-end center conductor resistance has been measured as approximately 7.9Ω.
In order to assure low optical return loss below approximately -60 dB, waveguide ends in external modulator 16 were polished in plane at an angle of 6° from the normal with respect to the waveguide longitudinal axis. Fibers 15 and 19 had their mating end faces polished at the corresponding Fresnel angle of 8° 52'.
In accordance with the principles of this invention, a modulation chirp parameter for modulator 16--rather than being allowed to be randomly varying or attempted to be made zero as in the prior art--is adjusted to a substantially fixed, non-zero value in a predetermined, controllable manner. The desired value of the modulation chirp parameter is typically one which provides the lowest fiber dispersion penalty for the system. Herein, modulation chirp parameter αm represents the ratio of phase modulation to amplitude modulation as performed by external modulator 16. The modulation chirp parameter may be expressed as follows: αm =(dφ/dt)/(dI/dt)/2I, where t denotes time and φ and I are the instantaneous phase and intensity of the optical output from external modulator 16. Generally, the modulation chirp parameter is a function of the type of modulation, the modulation depth, and the operating point of the optoelectronic transducer being used for the transmitter. For the Mach-Zehnder external modulator shown in FIG. 3, which is (1) based on the linear electrooptic effect, (2) biased midway on its switching curve, and (3) driven by mathematically similar drive waveforms, αm is written in terms of modulated optical phase velocities for the optical signals in each arm (waveguide "A" or waveguide "B") of the interferometer. The phase velocities are written as ΔβA and ΔβB for the two different arms of the interferometer. As a result, modulation chirp parameter is equal to (1+r)/(1-r), where r=ΔβB /ΔβA. It is the function of controller 24 to adjust the ratio r so that a particular value of the modulation chirp parameter is achieved. As such, the controller adjusts the modulation chirp parameter by choosing unique peak-to-peak applied drive voltages so that in the small signal limit αm =(ΔVA +ΔVB)/(ΔVA -ΔVB). While this expression is derived for the Mach-Zehnder configuration in the small signal regime, it is accurate for relatively large values of modulation depth. From the description above, it is now understood that, by modifying the digital data signal appropriately in the controller to generate drive signals having the proper relative magnitude and sign of their amplitudes, it is possible to achieve modulation chirp parameters in the range from -∞<αm <+∞.
The capability of obtaining controlled and arbitrarily adjustable values of the modulation chirp parameter is demonstrated in FIGS. 4-7. With respect to these figures, a shorthand notation has been introduced for the waveguides and electrodes in which the subscript A refers to waveguide 164 or the drive signals applied to electrode 168 and the subscript B refers to waveguide 163 or the drive signals applied to electrode 169. The curves shown in each of these figures represent the drive waveforms, VA and VB, generated by controller 24, the approximate voltage difference between the drive waveforms, and the optical intensity of the modulated signal output by external modulator 16. In each of FIGS. 4 through 7, the drive waveforms are at approximately 2.5 GHz in various voltage ratios.
In FIG. 4, pure phase modulation is obtained with r=1 (αm =∞). In order to obtain pure phase modulation with a modulation index of unity, electrodes 168 and 169 receive drive voltages from controller 24 which were in phase and which individually exhibited a peak-to-peak voltage swing corresponding to a π phase shift. Curve 41 shows the drive signals to the two waveguides being substantially in phase and having the appropriate voltage swings so that ΔVA =ΔVB =V.sub.π. Curve 42 shows a negligible oscillation in the voltage difference between the drive voltages as approximately VB -VA. As expected, curve 43 shows a substantially constant output intensity due to pure phase modulation in the external modulator.
Pure amplitude modulation is shown in FIG. 5 wherein the ratio r is equal to negative one and the modulation chirp parameter is approximately zero. Pure amplitude modulation is achieved with the drive waveforms being the negative (complement) of each other, as shown by curves 51 and 52. This corresponds to the condition where ΔVA =-ΔVB =V.sub.π /2. The voltage difference between the drive waveforms oscillates in a periodic manner as shown in curve 53. Curve 54 shows the optical intensity oscillating between a high level and a low level corresponding, for example, to an alternating pattern of binary zeroes and ones.
FIG. 6 depicts the case of combined amplitude and phase modulation where the ratio r is approximately equal to 1/3 and the corresponding modulation chirp parameter is approximately 2. The drive waveforms are substantially in synchronism but exhibit different peak-to-peak voltages as shown by curves 61 and 62. The drive waveforms generated by controller 24 satisfy the following conditions: ΔVA =3V.sub.π /2 and ΔVB =V.sub.π /2. The optical intensity shown in curve 64 is dominated by amplitude modulation as the intensity switches between a logically high state and a logically low state.
FIG. 7 also depicts the case of combined amplitude and phase modulation. The resulting curves 71 through 74 are similar to those shown in FIG. 6. In FIG. 7, the ratio r is approximately equal to 3/5 so that the modulation chirp parameter value is approximately 4. The drive waveforms generated by controller 24 satisfy the following conditions: ΔVA =5V.sub.π /2 and ΔVB =3V.sub.π /2.
In a different experiment, the same external modulator was responsive to a 5 Gb/s pseudorandom non-return-to-zero (NRZ) digital data signal from the data source. The modulation chirp parameter value was varied by having the controller change the relative peak-to-peak drive signal voltages and their relative polarities. Particularly, it was determined that chirp values between -2.0 and +2.0 were desirable. In order to achieve chirp values in this range and simultaneously permit a modulation depth of approximately 100%, |ΔVA -ΔVB | is held constant to a value of approximately 4 V while |ΔVA +ΔVB | is varied between 0 V and 8 V. It was found that positive values of the chirp parameter led to additional dispersion penalty for transmission at 1.53 μm over 256 km of standard optical fiber (zero dispersion wavelength of 1.3 μm). As the controller varied the drive signals to produce negative values of the modulation chirp parameter, pulse broadening was mitigated at the dispersion penalty was minimized. Over 128 km of fiber, transmission using a chirp parameter of approximately -0.8 reduced the dispersion penalty by 0.7 dB as compared with chirpless modulation. It is contemplated that this technique may be used with return-to-zero (RZ) pulses. In the latter case, the technique is expected to provide identical chirp for each data time slot.
A semiconductor rib waveguide embodiment of the Mach-Zehnder interferometer external modulator is shown in FIG. 8. FIG. 9 shows details of one period for the quantum well structure within the waveguide. This external modulator is suitable for use in the system of FIG. 1 in accordance with the principles of the present invention.
The rib waveguide structure is grown by molecular beam epitaxy on a semi-insulating Fe-doped InP substrate 81 prepared by silicon ion implantation (350 keV, 5×1014 cm-2 activated at 775° C. for 15 sec.). Using standard etching techniques, a 2000 Å deep wet chemical etch is performed on the substrate to provide an n-type ground plane 82 approximately 1000 Å thick for easy isolation of individual devices and for reduction for parasitic capacities.
The rib waveguide structure includes silicon doped InAlAs cladding layers 87 and 89 and an electrooptically active waveguide core region 88. Upper cladding layer 87 has a thickness of approximately 4000 Å whereas lower cladding layer 89 has a thickness of approximately 2500 Å. Core region 88 comprises eight periods of a barrier, reservoir, and quantum well electron transfer structure (BRAQWETS) which is stackable. One period of the BRAQWETS is shown in FIG. 9 comprising electron reservoir 93, spacer layer 94, quantum well layer 95, and a barrier region. Electron reservoir 93 is a 280 Å thick layer of silicon doped InGaAlAs; spacer layer 94 is a 105 Å thick layer of InGaAlAs; quantum well layer 95 is a 70 Å thick layer of InGaAs; and the barrier region comprises InAlAs layer 96 having a thickness of 70 Å, Beryllium doped InAlAs layer 97 having a thickness of 140 Å, and InAlAs layer 98 having a thickness of 105 Å.
The Mach-Zehnder rib waveguide interferometer structure shown in FIG. 8 is defined by a wet chemical etching to have a rib width of approximately 5 μm and a height of approximately 1.465 μm. The transition region between the input waveguide 83 and either of the straight active portions of sections 84 and 85 is approximately 133.75 μm long. A similar dimension applies to the transition region between output waveguide 86 and the straight active portions of sections 84 and 85. The transition is accomplished via a 1 mm (radius of curvature) s-shaped waveguide bend to achieve a Y-branch angle of approximately 4° and a 9 μm center-to-center separation between parallel arms of the interferometer.
Electrical isolation is provided by helium ion implantation of a 5 μm region between the straight active portions of sections 84 and 85 and the adjacent Y-branch. An isolation of approximately 64MΩ between the two arms of the interferometer is accomplished by implanting a dose of 5×1013 cm-2 at 250 keV followed by annealing for 30 seconds at 450° C. Metallic contacts 91 and 92 fabricated from compositions such as standard chromium/gold are evaporated as shown over the straight active portions of sections 84 and 85. In addition, a metallic contact is formed over n-type layer 82 to contact the bottom groundplane.
The present invention is well suited for applications including optical fiber dispersion compensation, optical pulse compression, spread spectrum communications, and optical frequency and pulse generation. While the description above pertains wholly to a Mach-Zehnder interferometer structure for the external modulator, it is contemplated that other external modulator structures, either known now or developed in the future whose chirp parameter is controller, may be used. Certainly, other coplanar waveguide structures can be used for external modulation. Moreover, it is contemplated that a separate laser be associated with each waveguide to provide its CW output beam for subsequent modulation. In such an application, the optical beams produced by the separate lasers would be required to be at substantially the same optical frequency and be in a fixed phase relationship with respect to each other. Phase locking of the separate lasers provides the fixed phase relationship of the output optical beams.
In the example above, the output of the single laser source is split into two beams for the interferometer by a Y-branch splitter. Other apparatus such as a beam splitter or a directional coupler switch are contemplated for use in splitting a single output optical beam into multiple optical beams.
The waveguides employed in the external modulator have been described in the exemplary embodiment as single mode waveguides. It is contemplated that the separate waveguides can be replaced by a single waveguide supporting at least two modes, for example, a fundamental mode and a higher order mode. Generally, multimode waveguides are suitable for such an application.
The output of the individual waveguides is shown in the exemplary embodiments as being combined with a Y-branch combiner. It is contemplated that the combining of the optical beams can also be accomplished by using a 3 dB directional coupler switch or an ordinary beam splitter. It is further contemplated that the input beam splitting function and output beam combining function may be accomplished by any combination of beam splitting device and beam combining device, respectively, as described above.
While the embodiments described above employ waveguides which are substantially parallel, it is contemplated that any geometric relationship of the waveguides can be employed to achieve external modulation.
While the information modulated onto the optical beam is shown and described above as being substantially digital in nature, both analog and digital signals are contemplated for use with the present invention.
|Brevet cité
|Date de dépôt
|Date de publication
|27 oct. 1989
|9 juil. 1991
|Hoechst Celanese Corp.
|Cable system incorporating highly linear optical modulator
|23 janv. 1991
|31 mars 1992
|Gte Laboratories Incorporated
|Quadrature optical phase modulators for lightwave systems
|3 juil. 1986
|7 janv. 1987
|Westinghouse Electric Corporation
|Electro-optical comparator
|Titre non disponible
|Brevet citant
|Date de dépôt
|Date de publication
|18 aoűt 1993
|26 sept. 1995
|Matsushita Electric Industrial Co., Ltd.
|Analog optical transmission system
|30 avr. 1993
|19 déc. 1995
|At&T Corp.
|Optical soliton generator
|30 nov. 1994
|28 mai 1996
|Telefonaktiebolaget Lm Ericsson
|Device and method for dispersion compensation in a fiber optic transmission system
|25 mai 1995
|4 juin 1996
|Northern Telecom Limited
|Chirp control of a Mach-Zehnder optical modulator using non-equal power splitting
|2 mars 1995
|15 oct. 1996
|Lucent Technologies Inc.
|Multifrequency lightwave source using phase modulation for suppressing stimulated brillouin scattering in optical fibers
|31 mai 1995
|29 oct. 1996
|Pirelli Cavi S.P.A.
|Active-mode-locking optical-fibre pulsed laser generator having a variable instantaneous frequency
|7 juin 1995
|4 mars 1997
|Lucent Technologies Inc.
|Method and system for reducing chirp in an optical cummunication system
|7 juin 1995
|15 avr. 1997
|Lucent Technologies Inc.
|Method and system for reducing chirp in external modulation
|29 sept. 1994
|27 mai 1997
|Imra America, Inc.
|Frequency chirp control and compensation for obtaining broad bandwidth ultrashort optical pulses from wavelength-tunable lasers
|3 avr. 1996
|28 juil. 1998
|General Instrument Corporation Of Delaware
|Optical modulator for CATV systems
|30 mai 1997
|9 févr. 1999
|Sdl, Inc.
|Optimized interferometrically modulated array source
|1 avr. 1996
|23 mars 1999
|Fujitsu Limited
|Optical transmission system employing single mode optical transmission fiber
|19 juil. 1996
|20 avr. 1999
|Uniphase Telecommunications Products, Inc.
|Velocity-matched traveling-wave electro-optical modulator using a benzocyclobutene buffer layer
|24 juin 1998
|29 juin 1999
|Integrated Optical Components Limited
|Optical modulator
|20 oct. 1997
|23 nov. 1999
|Lucent Technologies Inc.
|Laser transmitter for reduced signal distortion
|20 juin 1997
|30 mai 2000
|Lucent Technologies Inc.
|Semiconductor interferometric optical wavelength conversion device
|24 juil. 1998
|20 févr. 2001
|Uniphase Telecommunications Products
|Differential drive optical modulator
|26 janv. 1999
|6 mars 2001
|Mitsubishi Denki Kabushiki Kaisha
|Mach-Zehnder modulator
|21 sept. 1999
|6 mars 2001
|Jds Uniphase Corporation
|Velocity-matched, traveling-wave electro-optical devices using non-conductive and conductive polymer buffer layers
|6 oct. 1999
|11 déc. 2001
|Codeon Corporation
|Apparatus for externally modulating two optical channels at the same time
|10 févr. 2000
|30 avr. 2002
|Codeon Corporation
|Optical modulator having coplanar electrodes for controlling chirp
|28 nov. 2000
|21 mai 2002
|Jds Uniphase Corporation
|Optimized interferometrically modulated array source
|27 mars 2000
|21 mai 2002
|Codeon Corporation
|Variable chirp modulator having three arm interferometer
|8 févr. 2001
|6 aoűt 2002
|Codeon Corporation
|Low-loss electrode structures for optical modulation applications
|17 sept. 1998
|3 déc. 2002
|Jds Uniphase Corporation
|Optimized interferometrically modulated array source
|11 janv. 2001
|10 déc. 2002
|Codeon Corporation
|Modulation systems using dual channel optical modulators
|12 févr. 2001
|7 janv. 2003
|Codeon Corporation
|Resonant optical modulators with zero chirp
|18 mars 2002
|25 févr. 2003
|Codeon Corporation
|Optical modulator having coplanar electrodes for controlling chirp
|15 mai 2001
|22 avr. 2003
|Modetek, Inc
|Optical modulator with integrated driver
|15 sept. 1997
|27 mai 2003
|Fujitsu Limited
|Optical transmission system using in-line amplifiers
|2 juil. 2001
|8 juil. 2003
|Phasebridge, Inc.
|Hybridly integrated optical modulation devices
|1 aoűt 2001
|22 juil. 2003
|The Charles Stark Draper Laboratory, Inc.
|Non-invasive pipe inspection system
|17 mai 2000
|4 nov. 2003
|Siemens Aktiengesellschaft
|Method and system for generating return-to-zero signals
|13 févr. 2001
|11 nov. 2003
|Codeon Corporation
|Loss prevention structures for optical modulation applications
|26 déc. 2001
|23 mars 2004
|Lucent Technologies Inc.
|Electro-optical modulators
|6 sept. 2000
|15 juin 2004
|The Charles Stark Draper Laboratory, Inc.
|Non-invasive pipeline inspection system
|16 oct. 2001
|6 juil. 2004
|Ando Electric Co., Ltd.
|Low coherent reflectometer
|9 oct. 2001
|21 sept. 2004
|Codeon Corporation
|Optical modulator with programmable chirp
|22 janv. 2004
|16 nov. 2004
|Lucent Technologies Inc.
|Electro-optical modulators
|28 déc. 2000
|23 nov. 2004
|Fujitsu Limited
|Optical transmission system and dispersion compensator
|13 sept. 2002
|14 déc. 2004
|Lucent Technologies Inc.
|Push-pull thermooptic switch having single control signal
|22 sept. 2003
|27 sept. 2005
|Kabushiki Kaisha Toshiba
|Apparatus and method for optical modulation
|22 nov. 2004
|7 févr. 2006
|Schleifring Und Apparatebau Gmbh
|Device for optical signal transmission between two units movable relative to each other
|28 févr. 2005
|25 avr. 2006
|Sumitomo Osaka Cement Co., Ltd.
|Optical waveguide element
|3 févr. 2004
|13 juin 2006
|Lucent Technologies Inc.
|Optical digital-to-analog converter
|6 oct. 2004
|3 oct. 2006
|Fujitsu Limited
|Optical transmission system and dispersion compensator
|30 avr. 2003
|3 oct. 2006
|Fujitsu Limited
|Optical transmission system using in-line amplifiers
|14 janv. 2002
|31 oct. 2006
|Qinetiq Limited
|Travelling-wave guide electro-optic modulator
|24 aoűt 2006
|28 aoűt 2007
|Fujitsu Limited
|Optical transmission system using in-line amplifiers
|28 sept. 2000
|18 déc. 2007
|The Regents Of The University Of California
|Integrated wavelength tunable single and two-stage all-optical wavelength converter
|19 sept. 2006
|20 mai 2008
|Fujitsu Limited
|Optical transmission system and dispersion compensator
|30 juin 2006
|28 avr. 2009
|Intel Corporation
|Circuit board-to-circuit board connectors having electro-optic modulators
|14 juil. 2009
|Photonic Systems, Inc.
|Bi-directional signal interface using photonic coupler
|30 juil. 2004
|15 déc. 2009
|Jds Uniphase Corporation
|Tunable laser source with monolithically integrated interferometric optical modulator
|28 mars 2007
|7 sept. 2010
|Emcore Corporation
|Externally modulated laser optical transmission system with feed forward noise cancellation
|16 mars 2007
|5 oct. 2010
|Photonic Systems, Inc.
|Bi-directional signal interface and apparatus using same
|2 nov. 2010
|Photonic Systems, Inc.
|Bi-directional signal interface
|2 mars 2006
|7 déc. 2010
|Emcore Corporation
|Directly modulated laser optical transmission system with phase modulation
|2 févr. 2007
|1 févr. 2011
|Emcore Corporation
|Optical transmission system with directly modulated laser and feed forward noise cancellation
|2 aoűt 2010
|20 sept. 2011
|Emcore Corporation
|Externally modulated laser optical transmission system with feed forward noise cancellation
|22 nov. 2011
|Emcore Corporation
|Method and apparatus for controlling tunable transmitter chirp
|30 avr. 2013
|Photonic Systems, Inc
|Bi-directional signal interface with enhanced isolation
|22 mai 2010
|17 juin 2014
|Photonic Systems, Inc.
|Wide-bandwidth signal canceller
|22 mai 2009
|21 oct. 2014
|Photonic Systems, Inc.
|Bi-directional signal interface
|8 aoűt 2014
|8 déc. 2015
|Photonic Systems, Inc.
|Same-aperture any-frequency simultaneous transmit and receive communication system
|22 mars 2001
|1 nov. 2001
|Fow-Sen Choa
|System and method for reducing differential mode dispersion effects in multimode optical fiber transmissions
|16 oct. 2001
|23 mai 2002
|Ando Electric Co., Ltd.
|Low coherent reflectometer
|5 mars 2001
|9 janv. 2003
|Tohru Sugamata
|Optical waveguide
|9 oct. 2001
|10 avr. 2003
|Codeon Corporation
|Optical modulator with programmable chirp
|25 nov. 2002
|17 juil. 2003
|Andrekson Peter A.
|Method and apparatus for improving performance in noise limited optical transmission systems
|30 avr. 2003
|16 oct. 2003
|Fujitsu Limited
|Optical transmission system using in-line amplifiers
|13 sept. 2002
|18 mars 2004
|Doerr Christopher R.
|Push-pull thermooptic switch having single control signal
|14 janv. 2002
|18 mars 2004
|Heaton John Michael
|Travelling-wave guide elctro-optic modulator
|22 janv. 2004
|5 aoűt 2004
|Erben Christoph Georg
|Electro-optical modulators
|22 sept. 2003
|20 janv. 2005
|Kabushiki Kaisha Toshiba
|Apparatus and method for optical modulation
|30 juil. 2004
|3 févr. 2005
|Fish Gregory A.
|Tunable laser source with monolithically integrated interferometric optical modulator
|6 oct. 2004
|3 mars 2005
|Fujitsu Limited
|Optical transmission system and dispersion compensator
|22 nov. 2004
|16 juin 2005
|Harry Schilling
|Device for optical signal transmission between two units movable relative to each other
|28 févr. 2005
|21 juil. 2005
|Sumitomo Osaka Cement Co., Ltd.
|Optical waveguide element
|3 févr. 2004
|4 aoűt 2005
|Young-Kai Chen
|Optical digital-to-analog converter
|10 juin 2004
|29 déc. 2005
|Matsushita Electric Industrial Co., Ltd
|System, device, and method for radio frequency optical transmission
|2 mars 2006
|21 sept. 2006
|John Iannelli
|Directly modulated laser optical transmission system with phase modulation
|24 aoűt 2006
|21 déc. 2006
|Fujitsu Limited
|Optical transmission system using in-line amplifiers
|19 sept. 2006
|18 janv. 2007
|Fujitsu Limited
|Optical transmission system and dispersion compensator
|14 févr. 2006
|16 aoűt 2007
|Burns William K
|Bi-directional signal interface using photonic coupler
|22 févr. 2006
|23 aoűt 2007
|Al-Chalabi Salah A
|Secure optical communication system
|28 mars 2007
|6 sept. 2007
|Emcore Corporation
|Externally modulated laser optical transmission system with feed forward noise cancellation
|30 juin 2006
|3 janv. 2008
|Sanjay Dabral
|Circuit board-to-circuit board connectors having electro-optic modulators
|30 juin 2006
|29 mai 2008
|Sanjay Dabral
|Testing microelectronic devices using electro-optic modulator probes
|16 mars 2007
|18 sept. 2008
|Photonic Systems, Inc.
|Bi-directional signal interface and apparatus using same
|20 mars 2008
|22 janv. 2009
|Stephen Krasulick
|Method and apparatus for controlling tunable transmitter chirp
|22 mai 2009
|1 oct. 2009
|Photonic Systems, Inc.
|Bi-Directional Signal Interface
|22 oct. 2009
|Photonic Systems, Inc.
|Bi-directional signal interface with enhanced isolation
|12 juin 2009
|5 nov. 2009
|Photonic Systems, Inc.
|Bi-Directional Signal Interface
|12 mai 2009
|11 nov. 2010
|Alcatel-Lucent Usa Inc.
|Semiconductor thermooptic phase shifter
|2 aoűt 2010
|27 janv. 2011
|Emcore Corporation
|Externally modulated laser optical transmission system with feed forward noise cancellation
|4 oct. 2012
|23 oct. 2014
|Xmw Inc.
|Ka-band high power amplifier structure having minimum processing and assembling errors
|6 déc. 2012
|17 déc. 2013
|Emcore Corporation
|Directly modulated laser optical transmission system with phase modulation
|17 févr. 2006
|2 juil. 2008
|Amplitude modulation effect compensating apparatus
|28 aoűt 2002
|11 mai 2006
|Schleifring Und Apparatebau Gmbh
|Optical cable for transmission of data has transmitter at one end and receiver at other end and movable sensor device between two ends
|16 juin 1995
|17 janv. 1996
|PIRELLI CAVI S.p.A.
|Active-mode-locking optical-fibre pulsed laser generator having a variable instantaneous frequency
|2 aoűt 1995
|6 mars 1996
|Fujitsu Limited
|Optical transmission system with optimisation of transmission conditions
|22 nov. 1996
|22 oct. 1997
|Fujitsu Limited
|Optical transmission system using dispersion compensation
|9 sept. 2002
|2 avr. 2003
|Kabushiki Kaisha Toshiba
|Apparatus and method for optical modulation
|2 aoűt 1995
|3 oct. 2007
|Fujitsu Limited
|Optical transmission system
|14 janv. 2002
|25 juil. 2002
|Qinetiq Limited
|Travelling-wave guide electro-optic modulator
|13 mai 2003
|11 déc. 2003
|Schleifring Und Apparatebau Gmbh
|Device for optical signal transmission between two units that are displaced in relation to one another
|Classification aux États-Unis
|398/182, 385/8
|Classification internationale
|Classification coopérative
|Classification européenne
|22 mai 1992
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text:
What database software will open a .db5 file? Namely the Windows Live Photo Gallery Pictures.db5 database. I'd like to see the design and also the raw table data if possible.
It's not because it has a .db5 extension that it means this is a database readable by other applications? I especially think it's NOT a dBase database.
It's most probably a proprietary format. Unless it's documented somewhere on MSDN, or reverse-engineered by someone, I doubt it can be read easily.
I played with this a bit last year. Assuming they've not changed the format for the 2011 version, it's a SQL Server Compact (.sdf) database.
The latest version is 3.5, I recall I had to convert it from 2.x before I could work with it.
db5 is a database format. There was an application called dBase-5, may be that created the ending...
You should be able to open DBase-Databases with Access (MSO) or Base (OOo), or any other tool which support ODBC-like connections.


text:
Police: Man Dies After Fall From Boat in Michigan
Posted: 10/19/2011 - Authorities say he slipped or fell from his rain-slicked boat.
Posted: 10/19/2011 - Authorities say he slipped or fell from his rain-slicked boat.
Posted: 10/19/2011 - It issued a budget shortfall figure of $1.7 million last month.
Updated: 10/19/2011 - There are several different types of thermometers.
Posted: 10/19/2011 - A survey will be released Wednesday by U of M.
Posted: 10/19/2011 - It's now planned for December 4.
Posted: 10/19/2011 - The company wants to replace three 5-mile segments, including a section that passes through Marshall and under the Kalamazoo River.
Posted: 10/19/2011 - Matthew Bolick died in 2009.
Posted: 10/19/2011 - It's part of a cost-cutting effort.
Posted: 10/19/2011 - It's a $20 million project.
Updated: 10/18/2011 - The Lansing School District's dropout rate is higher than the rate in urban school districts in Detroit, Flint, Grand Rapids and any other major Michigan city.
Posted: 10/18/2011 - Candidates attack Herman Cain over "999" plan.
Posted: 10/18/2011 - Senate Majority Leader says Economic Development committee will vote on bill creating partnership with Canada.
Updated: 10/19/2011 - A female resident at Reed Manor in Jackson was found dead in her apartment on Saturday. Police have confirmed she was decapitated. A suspect, who is also a resident at Reed Manor, is in custody.
Updated: 10/18/2011 - A 23-year-old man is killed in a shooting in a parking lot of a south Lansing shopping plaza.
Posted: 10/18/2011 - Gov. Snyder signs bills that ends lifetime health care benefits for state lawmakers. The change effects senators and representatives who have not served at least six years in the Legislature before Jan. 1, 2013.
Updated: 10/18/2011 - $10,000 being offered for information leading to arrest of gunman.
Updated: 10/18/2011 - More jobs, more business, and no risks for taxpayers: that's how Governor Rick Snyder is describing a proposed new bridge from Detroit to Canada. The idea is facing strong opposition, and today the governor made his case for something he calls "critically important" to Michigan.
Updated: 10/18/2011 - Police say the man approached kids while in their yards in Jackson County's Hanover area.
Posted: 10/18/2011 - Utility says people smelled a small leak of a harmless chemical that is added to natural gas.
Posted: 10/18/2011 - Governor wants to wait until January before deciding how to spend extra money.
Posted: 10/18/2011 - Police confirm that 59-year-old Shirley Meeks' body had been decapitated when it was discovered in her Jackson apartment Saturday.
Posted: 10/18/2011 - Demand for construction and skilled trade workers is growing in Michigan
Posted: 10/18/2011 - The Antrim County man maintains his innocence and declined to speak at the sentencing.
Posted: 10/18/2011 - The owner says the Saginaw construction project kept customers away this summer, leading to his decision to close.
Updated: 10/18/2011 - Prices can start as low as zero and each bid increases the price only a penny or two, so the deals look amazing.


text:
Microreactors in organic chemistry and catalysis [electronic resource]
- Responsibility
- edited by Thomas Wirth.
- Language
- English.
- Edition
- 2nd completely rev. and enl. ed.
- Imprint
- Weinheim, Germany : Wiley-VCH, 2013.
- Physical description
- xix, 465 p. : ill.
Available online
More options
- Contributor
- Wirth, Thomas.
- ebrary, Inc.
- Bibliography
- Includes bibliographical references and index.
- Publisher's Summary
- For the second edition of 'Microreactors in Organic Chemistry and Catalysis' all chapters have been revised and updated to reflect the latest developments in this rapidly developing field. This new edition has 60% more content, and it remains a comprehensive publication covering most aspects of the topic. The use of microreactors in homogeneous, heterogeneous as well as biphasic reactions is covered in the main part of the book, together with catalytic, bioorganic and automation approaches. The initial chapters also provide a solid physical chemistry background on fluidics in microdevices. Finally, a chapter on industrial applications and developments covers recent progress in process chemistry. An excellent reference for beginners and experts alike.
(source: Nielsen Book Data)
Bibliographic information
- Publication date
- 2013
- Reproduction
- Electronic reproduction. Palo Alto, Calif. : ebrary, 2013. Available via World Wide Web. Access may be limited to ebrary affiliated libraries.
- 9783527332991
- 9783527659753 (e-book)
- 9783527659722 (electronic bk.)
- 3527659722 (electronic bk.)
- 3527659757 (e-book)


text: Knights4Christ 2 years ago 08:01 2 739 Esa Tarde nazareusrex.blogspot.com Share Like Galahad 2 months ago Hola amiga, estas aqui? I try to find your second site on internet. You had "La pagina catolica" and one other site. I would like to have some … [More] View 1 more postings. Please type your posting here


text:
- GhanaRetailFunding via ID Ghana
Comfort Tra...GhanaRetailFunding via ASA Initiative FNGO
Onua GroupGhanaRetailFunding via ID Ghana
Olga Yeyinou's Group
With the aim of increasing her buying power and expanding her business, she has requested and obtained a micro-loan from Finadev in order to provide adequate medical care to her children and to build a latrine in their house. Olga Yeyinou is on the left of the photo.
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In a group loan, each member of the group receives an individual loan but is part of a larger group of individuals. The group is there to provide support to the members and to provide a system of peer pressure, but groups may or may not be formally bound by a group guarantee. In cases where there is a group guarantee, members of the group are responsible for paying back the loans of their fellow group members in the case of delinquency or default.
Kiva's Field Partners typically feature one borrower from a group. The loan description, sector, and other attributes for a group loan profile are determined by the featured borrower's loan. The other members of the group are not required to use their loans for the same purpose.
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text: Is anyone familiar with these Carbon Drive belt systems? I have a customer who is considering this option and i am looking into it but I was wondering if anyone has experience with them, pros & cons, etc. Are they any more trouble than a regular chain driven setup, wear out faster, or harder to maintain, things as such. Any info is greatly appreciated. Thanks


text:
G15 viewfinder?
Started Jan 3, 2013 | Questions thread
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Stewart Cocker • Regular Member • Posts: 359
Re: G15 viewfinder?
You also get a green light confirming focus, previous poster makes an important point that rarely gets a mention re following fast moving subjects.
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