An electromechanical Braille cell assembly includes a plurality of parallel bimorph reeds. A first plurality of bimorph reeds is mounted to a first side of a printed circuit board by a first plurality of clips and a second plurality of bimorph reeds is mounted to a second side of the printed circuit board by a second plurality of clips. A frame has a top wall, a bottom wall, a first side wall in the form of an angle wall and a second side wall in the form of a flat wall. Pinholes are formed in the angle wall to accommodate Braille pins and the flat wall is slotted to accommodate a plurality of printed circuit boards. A monolithic cap covers all of the Braille pins. Pinholes formed in the cap receive the respective tips of the Braille cells when actuated bimorph reeds cause displacement of the Braille pins.

1. Field of the Invention
This invention relates, generally, to Braille readers. More particularly, it relates to a Braille reader that captures information displayed on a computer screen and transforms the information into Braille.
2. Description of the Background
Electronic devices that capture written information on a computer screen and transform the information into Braille are known. The known devices incorporate Braille cells that may include a plurality of hollow housings of parallelepiped construction, each of which houses either six (6) or eight (8) Braille pins. In the alternative, the housings may be solid and provided with bores for receiving the Braille pins. The pins are arranged in two (2) columns of three (3) or four (4) pins each.
When in repose, each pin is fully positioned within the hollow interior of its housing) or its bore. One of the walls of the housing has six (6) or eight (8) openings formed therein through which the uppermost tips of the pins selectively extend when activated.
The pins are selectively extended by actuator means to represent Braille characters. For example, when the letter "A" is detected on a computer screen, an electrical signal is sent to an actuator and the combination of pins that represents that letter in Braille is activated so that the combination of pins representing that letter are actuated so that they physically extend outwardly of tie housing so that they can be felt by a person reading Braille.
A bimorph reed, sometimes simply called a bimorph or a bimorph actuator, has s common center conductor sandwiched between two piezoceramic transducers. Series polled bimorph reeds are in common use in Braille cell actuators. Prior art Braille cell actuators incorporate series x-polled bimorph reed technology whereby the top and bottom elements are not electrically isolated from one another. The common center point is grounded and a high voltage is applied to one of the outer strips. A simple circuit drives the center conductor and fixes the outer conductor. This arrangement drives only one piezo element and the opposing element performs as a mechanical drag. Hence a bend is formed in the bimorph reed due to the difference in voltage-dependent expansion rates of the two parts of the bimorph reed, just as a bend is formed due to the difference in temperature-dependent expansion rates of the two parts of a bimetallic strip of the type commonly found in analog thermostats
A special metallic plating is applied to the outer piezo-ceramic contacts to enable soldering of the leads to a printed circuit board (PCB). The need for such special metallic plating increases the manufacturing costs associated with each bimorph reed.
Accordingly, there is a need for an improved bimorph reed construction that does not require such special metallic platting.
Sixteen (16) hand-soldered wires requiring thirty-two (32) solder joints are necessary to establish the electrical connections.
Thus there is a need for an improved means for connecting the leads to the PCB. Tie improved means would reduce the number of solder joints required and thus lower the manufacturing costs while increasing the reliability of the Braille cell.
Prior art Braille cells employ one individual cap per individual Braille cell. This results in a reading surface that is rough because it includes grooves, gaps and steps between the individual caps. The individual tolerances of each Braille cell results in a gap between the Braille cells and their surrounding enclosure. Moreover, the assembly of each Braille cell cap drives up the cost of manufacturing.
More particularly, prior art Braille cells employ one individual tactile pin cap per individual Braille cell. The tactile pin cap serves to position and align the pins and further provides cursor control buttons. The Braille cells and associated tactile pin caps positioned adjacent to each other collectively form the tactile surface. The use of individual cell caps for each Braille cell increases the manufacturing cost as aforesaid as well as the cost of materials. Additional stabilizers are required to position and align the individual cell caps. Strict tolerances are required to provide an acceptable tactile feel for the reader. The reader is sensitive to the separation that is inherent between each cell with this design. This unevenness between each cell is a limitation of all Braille displays heretofore known. To tactile users, the tactility of the grooves and cell-to-cell unevenness is comparable to the noise or flicker on a computer monitor experienced by a sighted user. Additionally, maintenance and replacement of the individual tactile pins is often necessary. Contaminants that build up on the pins must be removed or the pins must be replaced upon excessive wear.
Accordingly, there is a need in the art for an improved electromechanical tactile cell for use in a refreshable Braille display. Improvements in manufacturability and reparability are necessary in addition to enhancements in the tactile experience of the user.
The time required to manufacture a plurality of caps, each of which must be within certain tolerance limits, and to individually cap each Braille cell drives up the cost of manufacturing. Prior art cell caps produce a gap between the Braille module and the opening in the Braille display case. Each gap is a result of the accumulation of dimensional tolerances on a per cell basis. The art teaches use of an extra frame to correctly space each cell at a centerline. This approach is unsatisfactory because it further accentuates the unevenness of the display and provides additional area for contaminates.
It would therefore be advantageous if a better way could be found to cover the Braille cells.
The mounting of bimorph reeds has also been a source of problems. Some Braille cell assemblies employ adhesives to adhere the bimorph reeds to a printed circuit board. Some use clamps which themselves must be adhered or otherwise attached to a suitable mounting surface.
Thus there is also a need for an improved means for mounting a bimorph reed to a Braille cell assembly.
However, in view of the prior art considered as a whole at the time the present indention was made, it was not obvious to those of ordinary skill in this field that the identified improvements should be made nor would it have been obvious as to how to make the improvements if the need for such improvements had been perceived.
The longstanding but heretofore unfulfilled need for an improved Braille cell and Braille cell cap assembly is now met by a new, useful, and non-obvious invention. The electromechanical Braille cell assembly of the present invention and the improved Braille cell cap of this invention provides manufacturing cost reductions and substantial improvements in utility and reliability over prior art Braille cell and Braille cell cap assemblies. The present invention also reduces the labor required to manufacture the Braille cell and Braille cell cap assemblies, thereby further reducing the cost of the device.
More particularly, the present invention obviates the need for thirty-two (32) hand-soldered joints and for the routing of sixteen (16) jumper wires, thereby facilitating the manufacturing process and improving the reliability of the product. Additional manufacturing improvements are realized through improved alignment between the Braille pins and the bimorph reeds, also known as bimorph strips or bimorph actuators or simply bimorphs.
The novel Braille cell assembly includes a universal mounting means forming a part of an Original Electronic Manufacturer (OEM) solution. The novel Braille assembly therefore defines a standard for interfacing with the assembly.
More particularly, the novel Braille cell assembly includes a plurality of parallel polled bimorph reeds. Each bimorph reed or strip includes a top plate, a bottom plate, and a center conductor strip sandwiched therebetween. A virtual bimorph ground is provided by grounding the center conductor, by electrically isolating the top and bottom plate from each other, and by applying a high voltage to both the top and bottom plates so that neither plate is a mechanical drag on the other as in prior art bimorph strips.
A novel clip mounts each bimorph reed to a printed circuit board. Each clip includes a horizontal top wall soldered to the printed circuit board and a horizontal bottom wall soldered to the PCB. A top arm formed integrally with the horizontal top wall has a linear contact area formed by a part that extends downwardly to the linear contact area and upwardly therefrom. A bottom arm formed integrally with the horizontal bottom wall has a linear contact area formed by a part that extends upwardly to the linear contact area and downwardly therefrom. The linear contact areas are spaced apart from one another by a distance that is slightly less than a thickness of a bimorph reed. A bimorph reed is slid between the two linear contact areas and is clampingly engaged by the inherent bias of the top and bottom arms.
Each clip, including its horizontal top and bottom walls and its top and bottom arms, is formed of an electrically conductive flexible and resilient material. The arms are inherently biased toward one another so that a bimorph when disposed in sandwiched relation therebetween, is clampingly engaged thereby.
The clips are positioned about mid-length of their associated PCB. Each bimorph reed is engaged near its trailing end by its associated clip. The respective leading ends of the bimorph reeds extend beyond the leading ends associated PCBs.
The Braille cell assembly of this invention includes a plurality of Braille cells, each of which preferably includes eight (8) Braille pins in a housing. Each pin is actuated to extend out of the housing by a bimorph reed. Thus, there are eight (8) bimorph reeds for each Braille cell. A first set of four (4) bimorphs are clippingly engaged to a first side of a printed circuit board to actuate a first column of four (4) Braille pins and a second set of four (4) bimorphs are clippingly engaged to a second side of the printed circuit board to actuate a second column of four (4) Braille pins.
In a preferred embodiment, twenty (20) printed circuit boards are mounted in a hollow frame structure, more particularly known as a chassis or backplane. As above-mentioned, each printed circuit board provides a mount for eight (8) bimorph reeds. Accordingly, each PCB drives one (1) Braille cell. In a preferred embodiment, known as a double decade, there are two (2) sets of ten (10) Braille cells mounted on the novel frame structure. Thus, there are twenty (20) PCBs and one hundred sixty (160) bimorph reeds mounted in the chassis/backplane. In a preferred embodiment, such collection of twenty (20) PCBs is considered a module. Each module is interconnectable with another module. Thus, a user may purchase one (1) module or any multiple thereof when purchasing a Braille display case. Advantageously, repairs are easily made by exchanging a good module for a broken or malfunctioning module so that a user need not purchase an entire Braille display case when a problem arises.
The chassis/backplane has a top wall, a bottom wall, a first, leading sidewall in the form of an angle wall and a second, trailing sidewall in the form of a flat wall. A horizontal section of the angle wall is disposed in abutting and coplanar relation to a leading edge of the frame top wall and the vertical section of the angle wall is disposed in abutting relation to the leading end of the frame bottom wall. The longitudinal extent of the frame top wall is thus less than the longitudinal extent of the frame bottom wall, the difference in longitudinal extents being equal to the longitudinal extent of the horizontal section of the angle wall.
The flat wall is disposed in abutting relation to the trailing edge of the top wall and the trailing edge of the bottom wall.
A plurality of sockets is mounted on the top wall of the frame, in depending relation thereto, with each socket having a trailing end disposed near a trailing edge of the top wall. Each socket is adapted to receive an upper, trailing longitudinal edge of an upstanding PCB.
A plurality of slots is also formed in the top wall to receive the respective leading ends of the PCBs.
Each PCB has a protuberance formed in its lowermost, trailing end. A corresponding plurality of slots is formed in the bottom edge of the flat wall of the frame to respectively receive the protuberances to thereby enhance the mounting of the PCBs within the frame.
A first plurality of clips is soldered to a first side of each printed circuit board and a second plurality of clips is soldered to on a second side of each printed circuit board as aforesaid. Each clip holds a bimorph reed in substantially parallel relation to the top and bottom walls of the frame and each center conductor of each bimorph reed is soldered to its associated PCB.
A plurality of sets of pinholes is formed in the horizontal section of the angle wall and each pinhole is adapted to slideably receive a Braille pin.
A first set of bimorph reeds clipped to a first side of a first PCB includes four (4) bimorph reeds having a common length. The bimorph reeds are staggered with respect to one another so that a leading end of a first, uppermost bimorph reed extends a first distance beyond a leading end of its PCB, a leading end of a second bimorph reed mounted below the first bimorph reed extends beyond the leading end of the first bimorph reed, a leading end of a third bimorph reed mounted below the second bimorph reed extends beyond the leading end of the second bimorph reed, and a leading end of a fourth bimorph reed mounted below the third bimorph reed extends beyond the leading end of the third bimorph reed.
A second set of bimorph reeds clipped to a second side of a first PCB also includes four (4) bimorph reeds having a common length. The bimorph reeds are staggered with respect to one another so that a leading end of a first, uppermost bimorph reed extends a first distance beyond a leading end of its PCB, a leading end of a second bimorph reed mounted below the first bimorph reed extends beyond the leading end of the first bimorph reed, a leading end of a third bimorph reed mounted below the second bimorph reed extends beyond the leading end of the second bimorph reed, and a leading end of a fourth bimorph reed mounted below the third bimorph reed extends beyond the leading end of the third bimorph reed.
Each bimorph reed is clipped to the printed circuit board so that a leading end of each bimorph reed is positioned beneath a Braille pin disposed in the pinholes formed in the horizontal section of the angle wall. The respective leading ends of the four (4) bimorph reeds on the first side of the PCB abut or are closely spaces apart from the lowermost ends of the pins in a first column of four (4) Braille pins in a Braille cell and the respective leading ends of the four (4) bimorph reeds on the second side of the PCB abut or are closely spaced apart from the lowermost ends of the pins in a second column of four (4) Braille pins in a Braille cell.
The Braille pins may be formed independently of one another or they may be formed in connected relation to one another so that one set of connected Braille pins is adapted to fit within one Braille cell. In the latter, eight Braille pins are releasably connected to one another so that individual pins of the set of connected Braille pins are detachable from one another after being placed into respective pinholes of a Braille cell.
Each pin of the plurality of Braille pins has a four (4) part construction. More particularly, each pin has a first, lowermost part of solid or hollow construction that may have a transverse cross-section of any predetermined geometrical configuration. A second part also has a solid or hollow construction that may have a transverse cross-section of any predetermined geometrical configuration but its breadth is greater than that of the first section. Accordingly, a first shoulder is formed where the first and second parts meet one another. A third part of the pin is of solid or hollow construction and may also have a transverse cross-section of any predetermined geometrical configuration. The breadth of the third part is less than the breadth of the second part, forming a second shoulder where said second and third parts meet. In a preferred embodiment, the third part has a non-circular cross-section such as a star-shaped cross-section, but any non-circular cross-section such as triangular, square, pentagonal, hexagonal, elliptical, oblong, crescent, and the like is within the scope of this invention.
The fourth part of each pin has a solid or hollow construction and may have a transverse cross-section of any predetermined geometric configuration. It has a breadth less than the breadth of the third part, thereby forming a third shoulder where said third and fourth parts meet. The fourth part includes a rounded free end adapted for tactile communication with a user of the inventive structure. The user feels the tip when the pin is extended, i.e., displaced from its position of repose by an actuated bimorph reed.
The tip of the first pin in the first column of pins is extended when voltage is applied to the uppermost bimorph reed in the first set of bimorph reeds. The tip of the second pin in the first column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the first bimorph reed. The tip of the third pin in the first column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the second bimorph reed and the tip of the fourth pin in the first column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the third bimorph reed.
The tip of the first pin in the second column of pins is extended when voltage is applied to the uppermost bimorph reed in the second set of bimorph reeds. The tip of the second pin in the second column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the first bimorph reed. The tip of the third pin in the second column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the second bimorph reed and the tip of the fourth pin in the second column of pins is extended when a voltage is applied to the bimorph reed mounted immediately below the third bimorph reed.
A monolithic cell cap covers each Braille cell of the plurality of Braille cells. It also covers a plurality of buttons that are dedicated to control of a cursor. More particularly, a first plurality of cursor-control buttons is mounted in upstanding to the top wall of the chassis/backplane. A first comb-like holder holds first plurality of buttons. Each button of the first plurality of buttons has a head and a stem, the head being enlarged with respect to its stem. The first comb-like holder includes parallel, contiguous teeth that are spaced apart from one another. The free end of each tooth is adapted to engage the heads of its associated button.
A second plurality of buttons is also mounted in upstanding relation to the top wall of the chassis/backplane. A second comb-like holder holds the second plurality of buttons. Each button of the second plurality of buttons has a head and a stem, the head being enlarged with respect to its stem. The second comb-like holder includes parallel, contiguous teeth that are spaced apart from one another. The free end of each tooth is adapted to engage the heads of its associated button. The first comb-like holder and the second comb-like holder are disposed in confronting relation to one another.
Each comb-like holder includes twenty (20) teeth. There being two (2) comb-like holders, there is a total of forty (40) buttons, i.e., two (2) buttons for each of the twenty (20) Braille cells in a module.
The bottom wall of the novel chassis/backplane is formed of a material that does not require additional isolation from the metal chassis to which it is mounted.
The monolithic cap that covers the first and second comb-like holders is releasably engaged to the top wall of the chassis/backplane. The monolithic cap has a first set of forty (40) openings formed therein to receive the respective heads of the buttons and a second set of one hundred sixty openings formed therein to receive the respective tips of eight (8) Braille pins of twenty (20) Braille cells when said tips are extended by actuation of their associated bimorph reeds.
The number of buttons and Braille cells may be changed to meet the requirements of various applications. The number of buttons and Braille cells of this illustrative embodiment is merely a preferred number.

This patent is subject to a terminal disclaimer.


Embodiments may relate to a graphical user interface (GUI). The GUI may include a first portion that displays an image related to images of a location. The GUI may also include a second portion that displays an image related to detection and ranging information of the location. The two images may be linked such that an interaction with an object in one portion of the GUI causes changes in the other portion of the GUI. Other embodiments may be described or claimed.

Images at a given location may be taken using a variety of image capture technologies. One such technology may include cameras such as visible-light cameras, infrared cameras, etc. Use of this technology may include capturing a variety of images taken at various angles from the capturing device. The images may then be combined to form a panoramic view of the location. Another such technology may include light detection and ranging (LIDAR), radio detection and ranging (RADAR), or some other similar technology. LIDAR may include illuminating the location with one or more bursts of laser light, and then measuring the reflections of those bursts to identify distances between the capturing device and objects at the location. Each technique may have different advantages and disadvantages. For example, image capture may provide the benefit of allowing a user viewing the resultant images to see details such as color, shape, etc., which may not be apparent in images based on LIDAR information. By contrast, LIDAR may allow for distance measurements between the capturing device and an object that reflects the bursts of laser light.


In a picture encoding and decoding method and apparatus, an object contour can be chain coded precisely even in the case where noise exists in the vicinity of object contour, and the object contour branched off can be coded with small quantity of codes. In the case where the branched part occurs in a feature point chain, by multiplexing branch code D1 to chain codes S23 and S22 and expressing as a tree structured feature point chain including the branch part of the object contour, an increase in number of chains can be controlled and the efficient chain coding can be conducted. Moreover, since the terminal branch chains having no branch point in the chain become the objects of thresholding, only noise elements can be effectively eliminated without cutting off the feature point chain showing the object contours.

1. Field of the Invention
This invention relates to a video signal coding apparatus and method, and a video signal decoding apparatus and method, and more particularly, relates to the video signal coding apparatus and method, and the video signal decoding apparatus and method which reduce the amount of generating code by detecting feature points of motion picture and chain coding the data of the feature points.
2. Description of the Related Art
Heretofore, in a system for transmitting a picture under the limited transmission band and a system for recording a picture in the recording media having the limited storage capacity, the low bit rate coding method to efficiently compress the picture data with fewer code is employed. As the method for coding video signal efficiently, a method in which input video signal is orthogonally transformed using DCT (Discrete Cosine Transform) and then suitably quantized according to the human visual characteristics in each frequency band, and the other method in which a picture is divided into subbands by the Wavelet base (the Wavelet transform) and each subband is weighted and coded have been used. According to these methods, the visual distortion is not conspicuous and high compression rate can be obtained.
However, in these coding methods, as the compression rate is increased, the block starts distorting and visually undesirable effects become obvious. Thus, a structure extraction coding system which extracts feature points of the picture structure (for example, points constructing edges (pixels)) and efficiently encodes the picture data at the feature points by picture feature point detection has been introduced as the coding system which does not produce visually undesirable distortion due to the high compression rate. The structure extraction coding system has been proposed in the specification and drawings of the U.S. patent Ser. No. 08/457,830 filed in Jun. 1, 1995 by this applicant.
FIG. 1 shows the construction of one example of a picture encoding apparatus for compressing a picture by the structure extraction coding method. In the picture encoding apparatus 1, input video signal S1 is input to a quantizer 2 and a two-dimensional change point detection circuit 3. The quantizer 2 quantizes the input video signal S1 and forms quantized coefficient S2. The quantized coefficient S2 is supplied to a chain coding circuit 4. The two-dimensional change point detection circuit 3 detects whether or not the input video signal S1 is feature point. The two-dimensional change point detection circuit 3 outputs feature point signal S3 of which value is "1" for example to the chain coding circuit 4 if the input video signal S1 is the feature point, and outputs the feature point signal S3 of which value is "0" for example to the chain coding circuit 4 if the input video signal S1 is not the feature point.
After the quantization by the quantizer 2 and the feature point detection by the two-dimensional change point detection circuit 3 have completed on one whole screen (one frame), the chain coding circuit 4 chain codes the position information on the point at which the feature point signal S3 is "1" (pixel) (the position of the feature point (coordinates)) in accordance with the quantized coefficient S2 and the feature point signal S3. Further, after multiplexing the quantized coefficient at the position of the feature point (the quantized coefficient of picture data at the pixel detected as feature point) to the position information, the chain coding circuit 4 outputs this as chain coding signal S4.
The chain coding signal S4 is supplied to a chain threshold circuit 5. The chain threshold circuit 5 removes the chain having the chain length of a threshold value T and below, and the removed chain coding signal is supplied to a buffer memory 6 as threshold chain coding signal S5. The threshold chain coding signal S5 is supplied to the buffer memory 6 to be stored once and then recorded in a recording media (not shown) or outputted to a transmission line. Output signal S6 of the buffer memory 6 is recorded in the recording media (not shown) as output signal of the picture encoding apparatus 1, or outputted to the transmission line. In addition, the buffer memory 6 is stored once the signal, so that the data size of the output signal S6 is smoothed. Therefore, the output signal of the picture encoding apparatus 1 is outputted to the recording media or the transmission line with the approximately constant data rate.
Here, the chain coding circuit 4 is constructed as shown in FIG. 2. The chain coding circuit 4 stores the quantized coefficient S2 in a coefficient frame buffer 10, and the feature point signal S3 in a mask frame buffer 11 respectively.
At this point, a X-coordinate register 12, a Y-coordinate register 13 and a status register 14 are initialized to "0" at the head of each frame. Moreover, a direction search device 15 holds the 0th to 2nd status referring to the content of the status register 14 until the X-coordinate register 12 and Y-coordinate register 13 point out the final coordinates of the frame, and repeats the following functions depending on the aforementioned 0th to 2nd status.
More specifically, at the 0th status, the direction search device 15 stores the coordinates of the point next to the coordinates presently stored in the X-coordinate register 12 and Y-coordinate register 13 observing in the order of line scanning, and makes this as the point coordinates to be processed. The direction search device 15 inputs the mask value of this point coordinates from the mask frame buffer 11, however, in the case where the mask signal is "0", it performs nothing.
On the other hand, if the mask signal S10 is "1", the direction search device 15 stores this point coordinates in a search X-coordinate register 16 and a search Y-coordinate register 17, and simultaneously initializes a counter 18 to "0" and then as well as outputting X, Y-coordinates of this point to a selector 19 as start point coordinates output S11, outputs "1" to a multiplexer 20 and a latch circuit 21 as effective data selection signal S12, and then inputs "1" to the status register 14.
After the above processing is complete, the direction search device 15 sets the mask value of the coordinates of this point in the mask frame buffer 11 to "0".
In this connection, the counter 18 is formed by three bit counter and adapted to output "0" to "7" as the count values.
When the direction search device 15 confirms that "1" is inputted in the status register 14, it becomes the first status. Under this first status if the mask value S10 of the coordinates specified by address signal S13 in the mask frame buffer 11 is "0", the direction search device 15 inputs "0" to the status register 14 when count value of the counter 18 is "7", and increments the count value of the counter 18 when the count value is less than "7".
On the other hand, in the case where the mask signal S10 is "1", the direction search device 15, as well as outputting "1" as effective data selection signal S12, sets the mask value of the point to which the mask frame buffer 11 corresponds to "0" and then inputs "2" to the status register 14.
The direction search device 15, upon confirming that "2" is inputted in the status register 14, becomes the second status. Under this second status if mask signal S10 of the coordinates specified by the address signal S13 in the mask frame buffer 11 is "0", the direction search device 15 inputs "0" to the status register 14 when the count value of the counter 18 is "7", and increments the count value of the counter 18 when the count value is less than "7".
On the other hand, in the case where the mask signal S10 is "1", it outputs "1" as effective data selection signal S12, and makes the mask value of the point to which the mask frame buffer 11 corresponds to "0".
A search X-coordinate ROM 23 and a search Y-coordinate ROM 24, making counter output S14 as address signal input, output X differential signal S15 and Y differential signal S16 to adders 25 and 26 respectively. Also, a direction ROM 27 outputs direction signal S17 to a latch circuit 21, a direction change signal generator 28, and a selector 19 making the counter output S14 as the address signal input.
An example of contents of the search X-coordinate ROM 23, search Y-coordinate ROM 24, and direction ROM 27 is shown in FIG. 3. Here, direction codes C0 to C7 used in the direction ROM 27 show each direction divided into eight, centering around A as shown in FIG. 4.
The address generator 22 receives search X-coordinate signal S18 which is the sum of the contents of search X-coordinate register 16 and X differential signal S15, and search Y-coordinate signal S19 which is the sum of the content of search Y-coordinate register 17 and Y differential signal S16, and the address generator 22 outputs address signal S13 to specify the readout address of (X, Y) coordinates in the coefficient frame buffer 10 and the mask frame buffer 11.
The latch circuit 21 holds the direction signal S17 when the effective data selection signal S12 is "1", and keeps holding it until the effective data selection signal S12 becomes "1" at the next time, and then obtains previous direction signal S20 by delaying for one sample and outputs this to the direction change signal generator 28.
The timing relation of effective data selection signal S12, direction signal S17, and the previous direction signal S20 is shown in FIG. 5. For explanation, direction codes of the direction signal S17 are lined up in numerical order of C0 to C38 in FIG. 5. However, in practice, direction codes are arranged according to the detected result of feature points.
The direction change signal generator 28 is inputted direction signal S17 and previous direction signal S20, and then outputs direction change signal S21 according to tables shown in FIG. 6 and FIG. 7. More specifically, the direction change signal generator 28 outputs direction change codes D0 to D5 or D6 corresponding to the direction change, such that if the present direction has not changed with respect to the previous direction, D0 is outputted as the direction change code, and if the present direction has changed by 45.degree., D1 is outputted, and if it has changed by 90.degree., D2 is outputted, and so on. In practice, as shown in FIG. 8, the code words having a small number of bits are allocated to the direction change codes having high occurrence probability, such as D0 and D1, and the code words having a large number of bits are allocated to the direction change codes having small occurrence probability, such as D3 and D6, i.e., the entropy coding is conducted in order to reduce the volume of information.
At the time when the effective data selection signal S12 is "1", the selector 19 refers the value of status register 14. In the case where the value of said status register 14 is "0", the selector 19 outputs the starting point coordinates output S11 to the multiplexer 20 as the position signal 22, in the case where the value of said status register 14 is "1", it outputs the direction signal S17, and when the value is "2", it outputs direction change signal S21.
At the time when the effective data selection signal S12 is "1", the multiplexer 20 multiplexes coefficient output S23 from the coefficient frame buffer 10, and position signal S22, and outputs these to the following chain threshold circuit 5 (FIG. 1) as the chain code signal S4.
With this arrangement, after the chain coding circuit 4 detects the feature point of the head of chain under the 0th status, it detects pixels around the feature point at the head of chain under the first status, and in the case where the feature point exists in the surrounding area, connects this feature point to the feature point at the head of chain by showing this feature point with direction signal S17, and then proceeds to the second status and searches pixel around the feature point detected at the first status. And in the case where the feature point exists in the surrounding area, connects this feature point to the feature point detected under the first status by showing this with direction change signal S21. Under the second status, if feature points are detected again around the feature points previously detected, the chain coding circuit 4 connects these feature points sequentially by showing these feature points with direction change signal S21.
Furthermore, under the first or the second status, in the case where no feature point exists around the feature point detected previously, this chain will be cut off and it returns to the 0th status and searches for the feature point to become the head of next chain in order of line scanning.
In the conventional chain coding system, edge chains having less than the fixed length T have been removed as noise by the chain threshold circuit 5 (FIG. 1) of the later stage, assuming that the contour of an object would be coded by one edge chain.
However, in the case where noise exists in the vicinity of contour of the object, there have been a problem that the contour of one object would be coded as multiple chain edges and coding efficiency became worse.
In the picture encoding apparatus using the structure extraction coding system described above, on status that the edge of one object is coded with one edge chain, the chain having the length of the predetermined length T and below is removed as noise by the chain threshold circuit 5 (FIG. 1) at the latter stage of the chain coding circuit 4.
However, there has been a problem that, by using such method, the edge of one object is encoded as plural edge chains if noise exists in vicinity of the object, so that the coding efficiency became worse.
Furthermore, if the thresholding are conducted by the length T on the chain coded edge, the edge chain of the object contour would be cut off as shown in FIG. 9.
Moreover, in the case where the object contours were branched, independent multiple chains would be formed, and as a result, coding efficiency has decreased.

Picture encoding method and apparatus and picture decoding method and apparatus


A semiconductor device is manufactured by the use of a glass substrate which has previously been heated. An amorphous semiconductor layer is formed on the previously heated glass substrate and then crystallized by heat. By virtue of the previous heating, shrink of the glass substrate after the crystallization process is reduced. Accordingly, internal stress is not generated in the crystallized semiconductor layer. The semiconductor device thus manufactured is superior in electrical property.

1. Field of the Invention
The present invention relates to a method for manufacturing a semiconductor device.
2. Description of the Prior Art
A technique of forming a non-single crystal semiconductor layer on a glass substrate by reduced pressure CVD or plasma CVD followed by heating the substrate at about 600.degree. C. to thereby crystallize the layer into a polycrystal semiconductor layer has been well-known in the field of manufacture of semiconductor devices. Explaining the process of this thermal crystallization, first the temperature is raised from room temperature (i.e. initial stage), second the temperature is maintained at about 600.degree. C. (i.e. intermediate stage) for a few hours to several tens hours, and finally the temperature is lowered to room temperature (i.e. last stage). If a cheap glass substrate utilized for a large-sized liquid crystal display device and so on is subjected to the thermal crystallization process at about 600.degree. C., since a cheap glass substrate has its strain point at about 600.degree. C., the glass substrate shrinks (that is, the volume of the glass at the last stage becomes smaller than that at the initial stage) and thereby internal stress is caused in a semiconductor layer provided on the substrate. Further, photolithography pattern to be used in the subsequent process is deformed due to the shrink of the glass substrate, so that mask alignment in the further subsequent process becomes difficult to carry out. According to an experiment, interface state in the semiconductor layer formed on the substrate was high due to the internal stress, therefore electrical property of the semiconductor layer was bad. For the above reason, a technique for obtaining on a glass substrate a semiconductor layer of excellent electrical property has been required in the field of manufacture of semiconductor devices.

Method for manufacturing a semiconductor device

Semiconductor Energy Laboratory Co., Ltd.


A continuous-conveyance bulk-cargo ship unloader in which a boom is provided with an elephant trunk that can swing from one end of the boom. The trunk has a hollow cylindrical shaft which accommodates an upright conveyor. At the bottom of the elephant trunk, is a free-sweeping cargo-intake unit that is provided with a cargo pickup, a lower section of the conveyor, and a conveyor loader for transferring cargo from the pickup to the conveyor section. Squeeze rollers are mounted in horizontal frames and positioned at varied heights along the upright conveyor, and these frames have an uppermost frame attached to the shaft. The remaining ones of the frames are suspended from a frame above at three or more points. A lowermost frame is releasably fastened to the cargo-intake unit and pivots along with the cargo-intake unit about a vertical axis at the bottom of the shaft. The trunk is arranged inclined to swing in both directions.

The invention concerns a continuous-conveyance bulk-cargo ship unloader. It has a boom. An elephant trunk swings from one end of the boom. The elephant trunk has a hollow cylindrical shaft. The shaft accommodates an upright conveyor. There is a free-sweeping cargo-intake assembly at the bottom of the elephant trunk. The intake assembly comprises a cargo pickup, the lower section of the conveyor, and a conveyor loader that transfers the cargo from the pickup to the conveyor section.
A continuous-conveyance bulk-cargo ship unloader is known from the as yet unpublished German patent application no. 4 125 109.1. At the bottom is a cargo pickup in the form of a scooper head or bucket wheel that rotates around an upright axis.
The cargo pickup transfers the cargo radially to another upright conveyor. The second conveyor can be a belt-sandwich conveyor and more specifically a foam-belt conveyor, a U-section conveyor, or a rippled-edge conveyor. Foam-belt conveyors are described in German Pat. Nos. 2 236 102, 2 333 100, and 2 261 115, U-section conveyors in Swedish Pat. Nos. 705 052-2 and 8 800 315-7, and rippled-edge conveyors in the as yet unpublished German application No. 4 121 996.1.
The screw conveyor and cargo pickup and the opening into the conveyor loader are positioned in relation to the axis of the belt-sandwich conveyor such that all the material will be flung as intended into the throat of the conveyor's intake slot.
The upright section of the belt-sandwich conveyor is inside the elephant trunk.
Belt-sandwich conveyors are upright conveyors that convey a bulk material by compressing it between two belts. At least one belt is driven. If only one is driven, the other is entrained by friction.
To allow flow rates ranging from zero to the maximum possible, the space between the belts must be variable within certain limits. The squeeze rollers, or at least the squeeze rollers resting against one of the belts, the pressure belt, can accordingly be mounted resiliently. Alternatively the pressure belt itself can be resilient, made of foam for example, and travel through a trough between the sets of rollers.
In the section of the conveyor in which the bulk material is conveyed upward, many directly adjacent rollers squeeze the ascending strand of the pressure belt against the ascending strand of the counterpressure belt. The rollers that squeeze the descending strands can be farther apart. The descending strands can also be squeezed by a farther-apart roller or roller trough against one of the rollers or troughs that squeezes an ascending strand.

Suspension and guide of a vertical conveyor in the discharge trunk of a ship unloader


A valve train for driving an engine valve in an internal combustion engine. A pump having a pressure chamber compresses and supplies fuel to the engine. An intake camshaft has valve cams for selectively opening and closing the intake valves and a pump cam for driving the pump. The intake camshaft has a torque fluctuation as a result of driving the intake valves and as a result of compressing fuel by the pump. A timing belt connects a crankshaft to the intake camshaft. The pump cam has a phase with respect to the intake camshaft to reduce a composite of the torque fluctuation (the net torque fluctuation) generated in the intake camshaft by the intake valves and the pump. This improves the life of the timing belt.

The present invention relates to a valve train having a camshaft for actuating intake valves or exhaust valves in an internal combustion engine. More particularly, the present invention pertains to a valve train that actuates a fuel pump by rotation of a camshaft.
In a typical engine, rotational force of a crankshaft is transmitted to camshafts, for example, by a timing belt. The camshafts are rotated, accordingly. Valve cams on the camshafts selectively open and close intake valves and exhaust valves. Fuel injected from fuel injection valves is mixed with air. When the intake valves are opened, the air-fuel mixture is introduced to combustion chambers of the engine. The air-fuel mixture then fills the combustion chambers and is combusted. The combustion of the mixture generates power of the engine. After combustion, exhaust gas is discharged from the combustion chambers when the exhaust valves are opened.
In the above described engine, fuel is pressurized and is supplied to the fuel injection valve by a fuel injection pump. Several types of mechanisms for actuating the fuel injection pump have been proposed (see "Fuel Pump Actuating Mechanism in Engine" disclosed in Japanese Unexamined Utility Model Publication No. 7-22062). In a mechanism of this type, a pump cam is provided on a camshaft for actuating a fuel injection pump. The pump cam contacts a piston of the injection pump thereby converting rotation of the camshaft to reciprocation of the piston. The reciprocation of the piston introduces fuel from a fuel tank into a pressurizing chamber of the pump. The piston then pressurizes the fuel and supplies the fuel to the fuel injection valves.
The torque of a camshaft fluctuates when it selectively opens and closes intake valves or exhaust valves. The intake valves and the exhaust valves are constantly urged by valve springs in a closing direction. When the valves are opened against the force of the springs, torque opposite to the direction of rotating of the camshaft acts on the camshaft. On the other hand, when the valves are closed, torque in the rotating direction of the camshaft acts on the camshaft. These torques fluctuate the torque of the camshaft. Also, the inertia of each valve is another cause of the torque fluctuation in the camshaft.
A fuel injection pump, which is actuated by a camshaft, applies a reactive force on the camshaft. The magnitude of the reactive force during its suction stroke is different from the magnitude during its compression stroke. In other words, the magnitude of the reactive force fluctuates. Therefore, the torque of the camshaft is fluctuated not only by actuation of the intake or exhaust valves, but also by actuation of the fuel injection pump. When the torque fluctuation caused by the intake or exhaust valves and the torque fluctuation caused by the fuel injection pump overlap and are additive, the resultant torque fluctuation in the camshaft results in an excessive tension of the timing belt. This shortens the life of the belt.
Wide torque fluctuation of the camshaft causes the tension of the timing belt to also widely fluctuate. Wide tension fluctuation of the belt vibrates the belt and causes the belt to resonate. The resonance of the belt further increases the tension of the belt. This further shortens the life of the belt.
Some engines use a timing chain or gears to transmit rotational force of a crankshaft to camshafts. In these types of engines, torque fluctuation of camshafts increases the tension of the chain and the load on the teeth of the gears. This shortens the life of the chain or the gears.
Replacing the valve springs with springs having weaker force or changing the cam profile of the intake or exhaust cams will reduce the torque fluctuation of the camshaft caused by actuation of intake or exhaust valves. As a result, the tension of the timing belt will be decreased and resonation of the belt will be prevented. However, weaker valve springs and changed cam profiles degrade the performance (for example, the power) of the engine.

Valve train in internal combustion engine


A method and system for two and three dimensional mapping of tissue density and/or structural changes from image data and/or spatial reflected or transmitted signal maps, and correlating the maps to changes in collagen density. The method and system includes the steps of: receiving an image or spatial maps of acoustic-derived RF signal data from tissue comprised of multiple pixels, segregating the image into groups of pixels, each group of pixels having characteristics within a defined class, establishing a baseline set of classes corresponding to initial conditions of the imaged/mapped tissue, measuring a differential in the set of classes for a group of pixels, the differential corresponding to a change in pixel values for the group of pixels, correlating said measured differential to a density change for the tissue corresponding to the group of pixels, and overlaying an indication of collagen density over the tissue image or mapped signal responses correlated with thermal dose indicating a change in collagen density for the tissue.

Collagen is the major insoluble fibrous protein in the extracellular matrix and in connective tissue. There are at least nineteen types of collagen, but 80% to 90% of the collagen in the body is composed of the conventional well-known Type I, Type II, and Type III forms. The collagen molecule is a triple helix, each helical coil a biological polypeptide polymer constructed from glycine (C2H5NO2), alanine (C3H7NO2), proline (C5H9NO2), and hydroproline (C5H9NO3). As the three helices wrap around each other, hydrogen bonds form between each helix to maintain the structure. Collagen molecules pack together to form long, thin fibrils. The most prominent collagen types are:    Type I. The primary component of tendons, ligaments, and bones.    Type II. The primary protein constituent (more than 50%) in cartilage.    Type III. Strengthens the walls of hollow structures like arteries, the intestine, and the uterus.    Type IV. Forms the basal lamina (also called the basement membrane) of epithelia.
As a support structure, collagen fibrils are found in many environments within the body. The strength and relative elasticity of the collagen structure allow tendon and ligament structures to function in their role which requires great strength to manipulate skeletal structures. Up to 90% of the dry weight of tendons is collagen (at least 30% of the total weight), up to 50% of the dry weight of articular cartilage and synovial tissue is collagen (5% to 30% of total weight). Collagen comprises 75% of the dry weight of skin.
The helical structure and the nature of the hydrogen bond cross-linking of the collagen molecule cause it to react when heated. The cross-linking bonds break and the helix, which is a type of spring structure, collapses somewhat. The result is a shrinkage, not unlike the process which occurs when a woolen garment is washed in hot water and heated in a dryer. The amount of shrinkage is a function of time and temperature [see FIG. 1] and is well known.
Several therapeutic remedies have been developed which utilize the thermal response of collagen to affect shrinkage and/or for treating disease and, thereby, therapy. Among these are capsulorrhaphy, or the shrinkage of the tendon and capsular properties of the joints, shrinkage of the endopelvic fascia to address urinary incontinence, shrinkage of the bladder neck to affect treatment for urinary incontinence, shrinkage of sub-epidermal collagen for producing tightening of tissue to affect cosmetic outcomes, thermal treatment of benign and malignant tumors, among others.
A limitation of procedures for collagen shrinkage, however, is that the cell necrosis accompanying those procedures [see FIG. 1] weakens the structural integrity of the fibrils. It is known that shrinking capsular tissue more than 20% will weaken a structure so much that it will distort more under normal forces than it would if there had been no shrinkage at all [see FIG. 2]. Treatment of tumors usually involves delivering a thermal dose that guarantees cell necrosis, thus significantly changing collagen structure.
Thermally-induced shrinkage procedures have been received with moderate success because they have often produced variable results. Collagen shrinkage is a function of both time and temperature, but relatively small variations in either time or temperature can have dramatic results on the level of shrinkage [see FIG. 3]. Structures experiencing overshrinkage are likely to have limited, or adverse results. Structures with insufficient shrinkage are likely to have limited results.
Some therapy systems measure tissue temperature during treatment using invasive probes and predict associated tissue modification, while others estimate the temperature based on power-time-temperature parametric curves established from imperical measurements. But, because thermal dose, and thus collagen shrinkage, is an integral function of both time and temperature in combination with spatial distribution, and since slight variations in temperature during a specific time period can cause dramatic changes in collagen shrinkage [see FIG. 3], temperature measurement alone is not truly sufficient. In response to the need to effectively determine dosage of the thermal treatment, a noninvasive measure of the thermal dose or its affects, including collagen changes, is badly needed.
Since optimizing collagen modification, including shrinkage, is the goal of specific procedures, what is needed is a system and method for directly measuring the shrinkage of the collagen structure, rather than temperature. A system and method which could monitor tissue properties concurrent with treatment, signaling the operator to halt thermal application when collagen shrinkage approaches 20% could produce greatly improved results [see FIG. 3], reducing the inconsistency associated with the thermal shrinkage procedures.
The limitations of the previous art for monitoring tissue treatment resulting from thermal injury are inadequate to provide information directly related to collagen changes sufficient to provide optimal control of extent of collagen structural modification, including shrinkage.
It has been demonstrated that changes in collagen content of tissue affects certain acoustic properties, namely the speed of sound in that tissue structure and the absorption of the acoustic energy as it passes through that tissue [see FIG. 4A]. It has been shown in the art that there is a linear function of both acoustic velocity and acoustic attenuation (see FIG. 4B) with variations in collagen content. Acoustic velocity changes 5 m/sec/(% change in collagen concentration) and acoustic attenuation changes 0.666 db/m/(% change in collagen concentration).
As an example, a 20% shrinkage in a collagen structure having an initial collagen content of 30% should cause a 25% increase in the % collagen by weight of the tissue structure. Since many collagen structures are 5% to 30% collagen (by weight), a 25% increase in density due to therapeutic shrinkage would cause a change in collagen content of 1.25% to 7.5%. These changes would correspond to changes in acoustic velocity of 6.25 m/sec to 37.5 m/sec, for initial collagen contents of 5% and 30%, respectively (see FIG. 5A). These changes would correspond to changes in acoustic attenuation of 0.833 db/m to 5 db/m, respectively [see FIG. 5B].
In addition to changes in acoustic velocity and attenuation, the structural patterns of the tissue change permanently as a function of thermally-induced necrosis and density changes. These patterns may be characterized in an analysis of the structures in the 2D or 3D acoustic image or in 2D spatial maps of acoustic signals that are reflected from or transmitted through the tissue in those locations. Applying pattern recognition methods and/or expert system techniques to the backscatter image or signal mapping data can yield useful information in addition to attenuation and velocity measurements alone.
Ultrasound (acoustic) imaging has been used in medical imaging for years to differentiate tissue structures. These imaging techniques have examined acoustic properties of ultrasound waves as they travel through and reflect off of tissue to distinguish tissue types and the boundaries between those types. These devices map tissue in two dimensions (along a plane in line with an imaging transducer) or three dimensions (by using multi-element imaging transducers or single-line imaging transducers whose focus or location changes during the process. Two of the acoustic properties used in these imaging techniques are acoustic velocity and acoustic attenuation. Further, structural change analyses using pattern recognition methods can provide an ability to track changes in tissue structure/collagen structure from baseline using backscattered image information.
The ability to map those changes in tissue and assign changes in collagen density to the mapped functions would allow users the ability to monitor, in real time, the therapy effect they are seeking to accomplish.

Collagen density and structural change measurement and mapping in tissue


A UV light emitting diode and a method of fabricating the same are provided. The light emitting diode includes an active area between an n-type nitride-based semiconductor layer and a p-type nitride-based semiconductor layer, wherein the active area includes a plurality of barrier layers containing Al, a plurality of well layers containing Al and alternately arranged with the barrier layer, and at least one conditioning layer. Each conditioning layer is placed between the well layer and the barrier layer adjacent to the well layer and is formed of a binary nitride semiconductor. The design of the conditioning layer can reduce stress of the active area while allowing uniform control of the composition of the well layers and/or the barrier layers.

Generally, a light emitting diode emitting UV light in a wavelength range of 200 nm to 365 nm may be used for various applications including a sterilization apparatus or an excitation source of a bio-aerosol fluorescent detection system.
A nitride-based light emitting diode capable of emitting UV light is typically grown on a growth substrate such as a sapphire substrate or an aluminum nitride substrate. In addition, fabrication of vertical type UV light emitting diodes is possible, e.g., examples disclosed in a published PCT application No. WO2008/054995 entitled "VERTICAL DEEP ULTRAVIOLET LIGHT EMITTING DIODES" in PCT application No. PCT/US2007/081634.

UV light emitting diode and method of fabricating the same


The present invention describes direct decoding of Error Correction Codes (ECC) such as, for example, FIRE and similar codes, and detecting and correcting errors occurring in burst, without requiring any pattern shift or sequential logic. According to the present invention, the syndrome of a code generated with a degree-d polynomial is split into sub-syndromes that are combined to form at least one kind of error pattern from which an error pattern is picked. If the picked error pattern does not correspond to an uncorrectable error and errors are not confined within first d bits, one of the sub-syndromes is selected according to the correction mode. The ranks of this selected sub-syndrome and picked error pattern in the Galois field generated by a factor of the degree-d polynomial are determined. Determining the rank of an error pattern vector being larger than vectors of a Galois field, in this Galois field, consists of extracting the burst of errors from the error pattern, determining the rank of the burst of errors in the Galois field and adjusting this rank on the basis of the position of the burst of errors in the error pattern. Ranks of this selected sub-syndrome and picked error pattern are subtracted to determine a group first vector. Then, the error pattern can be applied to the group determined by the group first vector so as to correct the message or data packet.

1. Field of the Invention
The present invention relates to Error Correcting Codes (ECC) in general, and more particularly applies to a class of Cyclic Redundancy Check (CRC) codes such as FIRE and similar codes capable of detecting and correcting errors occurring in bursts.
2. Background of the Invention
The rate at which data are transmitted through communications networks has dramatically increased in recent years. Fueled by advancements achieved in fiber and optoelectronic devices and techniques such as Dense Wavelength Division Multiplexing (DWDM), which allow multiplication of the bandwidth of a single fiber by merging many wavelengths on it, the telecommunications and networking industry developed devices capable of routing and switching the resulting large amount of data that converge, and thus must be dispatched, at each network node. Typically, routers and switches situated at those network nodes have now to cope with the requirement of having to move data at aggregate rates that must be expressed in hundreds of giga (109) bits per second while multi tera (1012) bits per second rates must be considered for new devices under development.
Due to the considerable progress that has been made in optoelectronics which has allowed the transport of data from node to node at such high rates, it remains that switching and routing of the data is still done in the electrical domain at each network node. This is due to no optical memory available yet that would permit the temporary storage of the frames of transmitted data while they are examined to determine their final destination. The temporary storage of data must still be done in the electrical domain using traditional semiconductor technologies and memories. However, the electrical technologies based on semiconductors have not enjoyed the same level of improvement as compared to the optoelectronic ones. Especially, the transmission of signals on printed ciruit (PC) boards and backplanes suffers intrinsic limitations due to the transmission medium (PC boards), the cables and the connectors that must be used to realize the interconnections. The state of the art for an electrical link is currently a 2.5 Gbps link while 5 and 10 Gbps links are considered for future development. However, in order to reach such a transmission rate in the electrical domain, while maintaining bit error rate (BER) at a low level, transmitted data must be encoded. To this end, a so-called 8B/10B code, developed under the auspices of the American National Standards Institute (ANSI) by a Task Group X3T9.3 of the Technical Committee in 1992, has been largely adopted. However, the use of the 8B/10B code contributes to reduce the actual link bandwidth to 2 Gbps. Hundreds and even thousands of those links need to be used to concentrate and dispatch the flows of bits entering and leaving an electrical Terabit per second switching node. Actually, at least five hundred 2 Gbps links IN and five hundred 2 Gbps links OUT would be required, per Terabit, to implement a switching node. Even though BER is low, the multiplication of those links and the huge throughput handled by the switching nodes make them susceptible to frequent errors. As an example, assuming that the BER on one link can be specified to 10−15, an already exceptionally good value, then one transmission error may happen about every 8 minutes (i.e. about 500 seconds) in a Terabit switching node (2×109×1000 links=2×1012). And, because the links are encoded, more than a single transmitted bit is likely to be affected after decoding. In the 8B/10B code mentioned hereinabove, a single transmission error can thus span over 5 decoded bits.
On the other hand, the very large scale integration (VLSI) progress of semiconductor technologies, i.e. continued miniaturization, reduced voltages, increasing memory bit counts, has revealed a type of error known as a "soft error". Soft errors are changes in the stored data of VLSI devices, that is, flip-flops, register arrays and Random Access Memories (RAMs). A soft error is caused when a high-energy particle traverses the semiconductor substrate (i.e. silicon), leaving a trail of free charges in its wake. These charges are collected in a very short time interval (about 30 ps) by logic circuitry elements. If the product of capacitance and voltage (i.e. the energy) of the circuit element is low enough, the collected charge may change the stored data. There is no permanent damage to the VLSI device. The circuit will function properly after the event; hence the name "soft error". Radiation-induced soft errors, such as the ones induced by cosmic particles, have been known in the industry for more than 20 years, for example, occuring in dynamic RAMs. It is only recently that the problem has been recognized in VSLI devices when the progress of the integration has led to store data bits in low-energy circuits that can be more easily disturbed.
The implications of soft errors occurring in the logic of a Terabit switching node, and of the errors that may occur on the numerous electrical links necessary to implement it, is that means should be taken to protect against them to keep switching function running error-free. Error correcting codes (ECC) must thus be implemented so the data packets handled at switching nodes are protected while they traverse them.
In the realm of correcting codes, FIRE codes are burst-error-correcting codes and, thus, are well adapted to cope with the kind of errors occurring on the electrical links as described hereinabove (i.e. in bursts spanning several contiguous bits after decoding). They can also take care of the soft errors of the VLSI devices used to implement the switching function since soft errors generally affect a single bit (i.e. a binary latch or a single bit of a RAM). A description of FIRE codes can easily be found in the abundant literature on ECC. Among many examples, one can refer to 'Error Control Coding', a book by Shu LIN and Daniel J. Costello, Prentice-Hall, 1983, ISBN 0-13-283796-X, herein incorporated entirely by reference, and more specifically to Chapter 9 on 'Burst-Error-Correcting Codes'.
If FIRE codes can handle the type of errors as discussed above, it remains that the correction of those errors implies the use of an ECC which must be feasible in a time compatible with the handling of data packets by a switching node. A Terabit per second class switching node of the kind considered here is concentrating and dispatching traffic through a few tenths of ports. Typically, port configurations are generally in the range of 16-port to 64-port. FIG. 1 illustrates a 16-port switch including 16 input ports 100 and 16 output ports 110. The core switching function 120 of a switching node, most often, manipulates small fixed-size data packets 130 including header 131 and data 132. A common size for a data packet is 64 bytes or 512 bits. Port speeds to consider range from 10 to 40 Gbps that is, corresponding either to an OC-192 line of the SONET hierarchy (North American Synchronous Optical NETwork; the European counterpart is called SDH, which stands for Synchronous Digital Hierarchy) for the lower value (10 Gbps) and to an OC-768 for the higher value (40 Gbps). Keeping in mind that switch ports are designed to actually sustain higher values than those quoted above (there is a speedup factor e.g., to provide for the segmentation of protocol frames in fixed-size packets), it can be seen that data packets must enter and exit switch 120 through each port at a rate of one packet every 8 nanoseconds to accommodate OC-768 communication lines with a speedup factor of 1.6 (i.e. with actual switch port speed=40×1.6=64 Gbps). This is the rate (i.e. 64 Gbps) at which ECC must be able to perform corrections in every output port adapter 140.
Very simple circuitry has long been proposed to decode FIRE and similar codes. The well-known standard technique is an error-trapping decoder, an example of which is shown in the above reference book 'Error Control Coding' in section 9.2. Also, improvements have been disclosed. For example, U.S. Pat. No. 5,936,978 dated Aug. 10, 1999 and titled 'Shortened FIRE Code Error-Trapping Decoding Method and Apparatus' describes an improved (faster) error-trapping decoder. Yet simple, error-trapping technique, including all known improvements such as the one of above mentioned patent, assumes that one can afford to shift the pattern of bits received so as to determine where the corrections to perform are (if any). Because the semiconductor technologies that can be used in practice to implement the necessary logic (i.e. CMOS) is now pushed to its limits of operation, the internal clock speed is becoming of the order of magnitude of the time left to handle a packet. Typically, the internal clock period of CMOS ASIC (Application Specific Integrated Circuits) devices can be tuned down to a 2–4 ns range for the fastest of the devices, with logic gate propagation time around 100 picoseconds, while, as stated above, the requirement is to process one 64-byte packet every 8 ns. This makes the state of the art error-trapping technique impractical to use.
Decoding FIRE and similar ECC codes that match the data packet processing speed requirement of Terabit per second switching nodes while still using relatively slow standard technologies like CMOS and not requiring any bit pattern shift is desired.

Apparatus and method for allowing a direct decode of fire and similar codes

International Business Machines Corporation


Provided is an organic EL display apparatus capable of opening and breaking a defective portion without degrading a normal portion of a pixel, and a method of producing the same. The method of producing an organic EL display apparatus in which a plurality of pixels including organic EL devices are arranged includes the steps of: forming an organic EL device formed of a light emitting layer made of an organic compound between a cathode electrode and an anode electrode (Step S1); detecting a defective pixel in which a cathode electrode and an anode electrode are short-circuited (Step 2); and repairing the defective pixel to be opened by selectively applying a voltage between the cathode electrode and the anode electrode with respect to the defective pixel (Step S3).

1. Field of the Invention
The present invention relates to an organic electroluminescence (EL) display apparatus, a method of producing the same, a method of repairing a defect, and a repair apparatus. In particular, the present invention relates to a method of selectively repairing a pixel having a defective portion in which a cathode electrode and an anode electrode of an organic EL device are short-circuited, so as to enhance a yield of a repair display.
2. Description of the Related Art
In recent years, an EL display apparatus (organic EL display) has been developed actively, which is capable of being made thinner than a cathode ray tube (CRT), obtaining a wider viewing angle than a liquid crystal display apparatus, and being reduced in weight and cost.
The organic EL display generally has a configuration in which an organic light emitting layer is interposed between an anode electrode and a cathode electrode, and light is emitted when a current flows between the electrodes by an external drive circuit. Hereinafter, a device including a pair of electrodes and an organic light emitting layer will be referred to as "organic EL light emitting device" or "organic EL device".
In a simple matrix system, an anode electrode and a cathode electrode interposing an organic light emitting layer are arranged so as to constitute an XY matrix electrode, and are orthogonal to each other. A crossing point of the XY matrix electrode constitutes one pixel.
According to operations of an active matrix organic EL display with a thin film transistor (TFT), a scanning pulse voltage is applied successively to a scanning line in an X-direction, and TFTs whose gate terminals are connected to the scanning line are turned on at a time. Simultaneously, a signal voltage is applied to a signal line in a Y-direction, and charge is accumulated in a capacitance of each pixel through the TFT. When scanning of one line is completed, the TFTs are turned off, and the charge accumulated in a pixel capacitance remains as it is. As a result, an arbitrary applied voltage is set.
In the organic EL display, in a case where the anode electrode and the cathode electrode interposing the organic light emitting layer are short-circuited, an organic EL device in that portion does not emit light, with the result that a non-lighting defect occurs.
The short-circuit between the electrodes is caused by adhesion of foreign matters, a pin-hole of an organic light emitting layer, or the like. Generally, the thickness of the organic light emitting layer formed between the electrodes is very small, that is, about several 10 nm to 100 nm, and a large number of non-lighting pixels are likely to be caused by the short-circuit between the electrodes. In the organic EL display, it is very difficult to prevent foreign matters of a sub-micron or less from adhering to an inside of a surface of a display, so there is a demand for the countermeasure against a non-lighting pixel.
On the other hand, it is known that such a non-lighting defect can be lit normally by burning out a short-circuited portion with a laser so as to insulate the short-circuited portion. However, it is difficult to find in which place of a pixel a short-circuited portion is present.
Japanese Patent Application Laid-Open No. 2004-199970 discloses a method of specifying the position of a heat generation portion caused by a short-circuit in a high-magnification field of view of an infrared temperature image detection microscope. However, according to the method, a step of laser repair (burning repair) is complicated and takes a long time, which increases the cost of one panel to a large extent.
As another method of burning repair, a method of repairing a short-circuited portion during aging is known. According to this method, in a manufacturing process of an organic EL device, aging processing of applying a voltage between an anode electrode and a cathode electrode is performed to open and break a film defective portion previously. The opening and breaking refers to making a defective portion non-conductive. The opening and breaking is considered to be caused by a phenomenon in which an electrode corresponding to a film defective portion is broken and opened (insulated) by Joule heat generated during aging or oxidized to be made non-conductive. The film defective portion subjected to the opening and breaking becomes a local non-light emitting state. However, the film defective portion is smaller than the whole pixels, so the film defective portion does not influence the quality of a display.
Japanese Patent Application Laid-Open No. 61-114493 discloses an aging method for an inorganic EL device as the method of performing opening and breaking by the aging. According to this method, a DC voltage is applied as a first aging step, whereby a defective portion present in a panel is broken in a small region.
Further, Japanese Patent No. 2,818,255 proposes the following method. That is, aging is performed such that an organic EL device is successively supplied with a DC forward voltage and a DC backward voltage, which are within a range of 1×104 to 1×107 (V/cm), for one second or longer, respectively, as a first aging step. After that, as a second aging step, a DC forward voltage is applied for a longer period of time than the first aging step.
Further, Japanese Patent No. 3,562,522 discloses a method in which a breakdown voltage of a defective portion and a breakdown voltage of an organic EL device are obtained, and then, an aging step is performed with a voltage range between the breakdown voltages being set to be a range of an applied voltage in the aging processing.
According to any of the above-mentioned methods, a voltage is applied to a normal pixel. Therefore, device degradation of a normal pixel is caused, which leads to inconvenience such as decrease in panel luminance and occurrence of display unevenness Further, in a case where a panel area is large, a current flowing through a panel increases. Therefore, power source wiring itself generates heat to be disconnected, and device degradation may be caused by the heat generation of a panel. Actually, it is difficult to apply the aging processing.

Organic electroluminescence display apparatus, method of producing the same, and method of repairing a defect


A system for providing efficient coupling between an elliptical mode laser source and a single mode transmission fiber is disclosed. In one embodiment, the system comprises a cruciform cylindrical lens formed as a pair of perpendicular cylindrical lenses to provide for separate magnification of the "fast" diverging component (i.e., this component passes through a "fast" cylindrical lens) and the "slow" diverging component of the beam (i.e., this component passes through a "slow" cylindrical lens). By decoupling the magnification requirements of the components of the elliptical beam, the beam may be transformed into an essentially circular beam, appropriate for coupling into a single mode fiber. In one arrangement of the present invention, a coupling efficiency of approximately 90% is possible (as compared with prior art coupling efficiency of about 44%). In an alternative embodiment, the pair of cylindrical lenses may be replaced by a monolithic lens, formed to comprise orthogonal front and rear cylindrical surfaces.

There are a variety of semiconductor lasers that emit an elliptical beam. For example, many GaAs-based lasers operating at wavelengths such as 650, 780, 810 and 850 nm all emit an elliptical beam. In particular, a conventional 980 nm InGaAs laser, often used as a pump laser source for optical amplification systems, emits such an elliptical beam. Since the associated optical systems utilize transmission fibers with a circular core, much of the launched power may be lost. In particular, conventional optical systems will capture only approximately 40% of the launched power from an elliptical beam.
One known solution to this problem is to utilize an anamorphic fiber micro-lens, which achieves a coupling efficiency of about 70%. However, the microlens requires very stringent alignment tolerances. Additionally, the ellipticity of the launched beam may vary, depending upon the manufacturer (for example, the ratio of far-field angles between the vertical and horizontal directions can vary from 2.5 to 4.5, depending upon the manufacturer). Thus, even the best anamorphic microlens design may not be suitable for all situations.
Therefore, a need remains in the art for a system of improving the coupling efficiency of elliptical beams into a single mode optical fiber.

Cruciform cylindrical lens for elliptical beam transformation


A laser pump cavity apparatus with integral concentrator provides improved thermal lensing control, cooling and fracture strength. The concentrator is formed around a doped solid-state laser medium by diffusion bonding, using a material different than the doped laser medium and with a substantially lower index of refraction, higher thermal conductivity and higher stress fracture strength than the doped laser crystal. The concentrator has a top cladding layer with a cylindrical focusing surface and a bottom cladding layer with a cylindrical focusing surface and may have edge cladding layers. Cold plates, each of which also has one cylindrical surface, are placed in thermal contact with the cylindrical surfaces of the top and bottom cladding layers. The cylindrical surfaces preferably have hyperbolic or quasi-hyperbolic shape. The laser pump cavity apparatus is preferably pumped with several laser diode arrays in directions transverse to a laser beam axis. The pumplight is injected from the laser diode arrays through the edge cladding layers in directions toward line foci of the cylindrical surfaces. The concentrator top and bottom cladding material is preferably sapphire and the doped solid-state laser medium is preferably Yb:YAG. The edge cladding layers are preferably thermally insulating to maintain a one-dimensional heat flow condition within the doped laser medium, by forming them of a material that has lower thermal conductivity than the material used for the top and bottom cladding layers. The edge cladding layers are preferably made of undoped YAG material

In integrating laser pump cavities, the pumplight is reflected more than once. Thus, pump absorption is superimposed during several passes through the slab. In integrated laser pump cavity devices with an integral concentrator such as as described in commonly assigned co-pending patent application No. 08/994,422 [Attorney docket 970508 ], pending, the doped laser crystal and the concentrator are typically both made of the same crystal type. The doped laser crystal and the undoped concentrator are generally made using diffusion bonding technology which is well known in the industry. Diffusion bonding technology produces a bond that is as strong as the host crystal and provides a good optical, mechanical and thermal interface. Conventional diffusion bonding is performed on crystals of similar type.
Diffusion bonding of dissimilar crystal types has recently been developed by Onyx Optics under a Phase I Small Business Innovative Research (SBIR) grant, funded by the U.S. government. Specifically, a 4 mm by 4 mm interface between ytrrium aluminum garnet (YAG) and sapphire (Al.sub.2 O.sub.3) was formed by the Onyx Optics diffusion bonding process that exhibited low stress birefringence (<10 nm/um wavefront retardation) without fine annealing, high bond strength (600 Mpa equivalent to bulk YAG), and high thermal shock resistance. The proposed uses to date do not include high power solid-state laser pump cavities with integral concentrators.

Laser pump cavity apparatus with improved thermal lensing control, cooling, and fracture strength and method


A method for modeling geological structures includes obtaining seismic data and using these data to derive an initial density model. Potential fields data is used to update the initial geophysical model by an inversion process using vector or tensor components of gravity and/or magnetic data. In regions having an anomalous density zone, the initial model includes a topographic or bathymetric surface and a 2D or 3D density model including the top of any zones of anomalous density. Potential fields data is then used to derive the lower boundary of the anomalous density zones by using an inversion process. The final density model from the inversion may be further refined using the seismic data in conjunction with the model obtained by inversion of the potential fields data. The model data are integrated two or three dimensions to determine an overburden stress for the subsurface that includes a proper treatment of the anomalous density zone. In an optional process, the seismic data can be processed in depth or time using the density model from the inversion to improve the quality of the velocity information adjacent to and beneath the anomalous bodies.

1. Field of the Invention
The present invention pertains to processing gravity and magnetic data using vector and tensor data along with seismic data and more particularly to the inversion of gravity and magnetic data and combining with seismic data for hydrocarbon exploration and development, and to detect abnormally pressured subterranean formations in general, and with specific application to areas underneath and around anomalies such as salt, igneous or magmatic formations.
2. Related Prior Art
In exploration for hydrocarbons in subsurface environments containing anomalous density variations has always presented problems for traditional seismic imaging techniques by concealing geologic structures beneath zones of anomalous density. Many methods for delineating the extent of the highly anomalous density zones exist.
U.S. Pat. No. 4,987,561, titled xe2x80x9cSeismic Imaging of Steeply Dipping Geologic Interfaces, issued to David W. Bell, provides an excellent method for determining the side boundary of a highly anomalous density zone. This patent locates and identifies steeply dipping subsurfaces from seismic reflection data by first identifying select data which have characteristics indicating that seismic pulses have been reflected from both a substantially horizontal and a steeply dipping interface. These data are analyzed and processed to locate the steeply dipping interface. The processed data are displayed to illustrate the location and dip of the interface. This patent, while helping locate the boundaries, provides nothing to identify the subsurface formations on both sides of the boundary.
There have also been methods for identifying subsurface formations beneath anomalous zones using only seismic data to create a model and processing the data to identify formations in light of the model. By further processing reflection seismic data, the original model is modified or adjusted to more closely approximate reality.
An example of further processing seismic data to improve a model is U.S. Pat. No. 4,964,103, titled xe2x80x9cThree Dimensional Before Stack Depth Migration of Two Dimensional or Three Dimensional Data,xe2x80x9d issued to James H. Johnson. This patent provides a method of creating a three-dimensional model from two dimensional seismic data. This is done by providing a method of ray tracing to move before stack trace segments to their approximate three-dimensional position. The trace segments are scaled to depth, binned, stacked and compared to the seismic model. The model can then be changed to match the depth trace segments that will be stacked better, moved closer to their correct three-dimensional position and will compare better to the model. This patent uses a rather extensive seismic process to modify a seismic model that is not accurate.
One source of geologic exploration data that has not been used extensively in the past is potential fields data, such as gravity and magnetic data, both vector and tensor data and using potential fields data in combination with seismic data to provide a more accurate depth model or to derive a velocity model.
Gravity gradiometry has been in existence for many years although the more sophisticated versions have been held as military secret until recently. The measurement of gravity has become more acceptable in the late eighteen hundreds when measuring instruments with greater sensitivity were developed. Prior to this time, while gravity could be measured, variations in gravity caused by the effect of a large nearby object at one location, the gravity gradient, could not be reliably measured.
It has been known since the time of Sir Isaac Newton that bodies having mass exert a force on each other. The measurement of this force can identify large objects having a change in density even though the object is buried beneath the earth""s surface or in other ways out of sight.
Exploration for hydrocarbons in subsurface environments containing anomalous density variations such as salt formations, shale diapers and high pressure zones create havoc on seismic imaging techniques by concealing geologic structures beneath zones of anomalous density. By utilizing gravity, magnetic and tensor gravity field measurements along with a robust inversion process, these anomalous density zones can be modeled. The spatial resolution obtained from this process is normally much lower resolution than that obtained from reflection seismic data. However, models obtained from gravity and magnetic data can provide a more accurate starting model for the seismic processing. Using the potential fields data models as a starting point for two dimensional and three dimensional seismic depth imaging greatly enhances the probability of mapping these concealed geologic structures beneath the zones of anomalous density.
Zones of anomalous density may also be associated with zones of anomalous fluid pressure. Typically, while drilling an oil or gas well, the density of the drilling mud must be controlled so that its hydrostatic pressure is not less than the pore fluid pressure in any formation along the uncased borehole. Otherwise, formation fluid may flow into the wellbore, and cause a xe2x80x9ckick.xe2x80x9d Kicks can lead to blowouts if the flow is not stopped before the formation fluid reaches the top of the well. If the fluid contains hydrocarbons, there is a serious risk of an explosion triggered by a spark. For this reason, wellbores are drilled with a slight excess of the borehole fluid pressure over the formation fluid pressure.
A large excess of the borehole fluid pressure over the formation fluid pressure, on the other hand, is also undesirable. Fractures in the borehole wall may result in loss of circulation of the drilling fluid, resulting in stuck drill strings. Even if drilling can be continued, it is slowed down, resulting in greater costs. Serious formation damage may also occur.
Pressure prediction is done by estimating certain key parameters that include the overburden stress or confining stress, which is defined as the total lithostatic load on a rock volume at a given depth, and the effective stress, which is defined as the net load on the grain framework of the rock at a given depth. These two relations are then used in the Terzaghi effective stress law to estimate the fluid or pore pressure. Terzaghi""s law states that:
Pc=Pe+Pp
where:
(Pc)=the confining stress
(Pe)=the stresses born by the grains, and
(Pp)=the stress born by the fluid.
Some workers treat a special case of Terzaghi""s law where the confining stress is assumed to be the mean stress as opposed to the vertical confining stress. It should be acknowledged that this difference exists, but that it does not effect the embodiments of the present invention as they will pertain to estimating the total overburden load, which can then be converted to either vertical confining stress or mean stress based on the stress state assumptions that are made. The current prior art used for estimating confining stress is to use a density log from a nearby calibration well and integrate the density data to obtain the overburden load. This calibration was then applied from the mudline down to depths usually beyond the depth of sampling to predict the overburden away from the calibration well.
It has long been recognized that velocities of seismic waves through sedimentary formations are a function of xe2x80x9ceffective stress,xe2x80x9d defined as the difference between the stress caused by the overburden and the pore fluid pressure. A number of methods have been used to measure the seismic velocities through underground formations and make an estimate of the formation fluid pressure from the measured velocities. Plumley (1980) and U.S. Pat. No. 5,200,929 issued to Bowers, (the ""929 patent) describe a method for estimating the pore fluid pressure at a specified location. The method also accounts for possible hysteresis effects due to unloading of the rock formation. The method utilized a pair of sonic velocity-effective stress relations. One relationship is for formations in which the current effective stress is the highest ever experienced. A second relationship is used when the effective stress has been reduced from the maximum effective stress experienced by the rock and hysteresis must be accounted for.
The ""929 patent uses density data from nearby wells or from a geologically similar well to obtain the overburden stress. In most circumstances, the overburden stress may be adequately described by general compaction models in which the density increases with depth, giving rise to a corresponding relation for the relation between depth and overburden. In the absence of well control, determination of the overburden stress even within a sedimentary column is problematic. Furthermore, there are circumstances in which the model of a density that increases uniformly with depth is not valid. In such cases, the assumption of increasing density with depth is violated and a different approach to estimation of the overburden stress is needed.
There are several types of situations that may arise wherein a model of density increasing with depth and compaction is not valid. In the first case, there is a region of abnormally high density in the subsurface, usually of magmatic origin. The region could consist of an extrusive or intrusive volcanic material having relative density of 2.8 or higher. When such a formation is present within a sedimentary section where the relative density is typically between 2.4 and 2.65, the result is an increase in the overburden stress underneath the formation over what would be determined by prior art calculations. On the other hand, a region of abnormally low density may occur from salt bodies (2.10) or shale diapirs. In such a case, the overburden stress is abnormally low compared to what would be determined by prior art methods. In either case, even if the effective stress could be determined from seismic velocity measurements, a formation fluid pressure determination based on a prior art density model would be invalid.
In prior art, it is common to extrapolate away from a control well to derive an initial pressure model. When abnormally pressured sediments are present having higher porosity and lower density than sediments in the control well, the model of increasing density with depth is violated and the confining pressure is overestimated. There is a need for a method to image subterranean formations which are responsive to potential fields and non-potential fields data. The present invention combines these data types to extract more useful information than either data type has provided before.
There is a need for a method for accurate determination of fluid pressures in the subsurface that (1) does not require the availability of density logs and (2) can more accurately determine the density of the subsurface in 2D or 3D away from and deeper than the limits of density from well control. Such a method should preferably be able to obtain fluid pressure even in the presence of anomalous formations that have densities significantly different from those expected in normal sedimentary columns or that predicted by density values in single or multiple wells. The present invention satisfies this need.
The present invention incorporates a robust inversion process for determining parameters and geologic structure representing subterranean formations including determining subsurface formation fluid pressures using seismic data in combination with vector and tensor potential fields data, both gravity and magnetics. One or more components of potential fields vector and tensor data are measured at a plurality of locations over a region including the anomalous formation. The potential fields may be either gravity fields or magnetic fields, vector and/or tensor. A geophysical model of the region including the anomalous formation is determined using gravity, magnetics, seismic or a combination of these. A value of the one or more components of the potential fields vector and tensor data at the plurality of locations is estimated for the model. A difference between the estimated values and the measured values at the plurality of locations is determined. The model of the region is updated based on the difference. The estimate of the value of the one or more components, the determination of the difference and the updating of the model is repeated until the difference reaches a minimum value. The updated model is used to determine the parameter of interest. Abnormal densities in the subterranean formations are commonly associated with a salt body, a shale diapir, and extrusive or intrusive igneous bodies. In one embodiment the parameter of interest can be combined with seismic data representing the same parameter for depth imaging to provide a geologic depth model and to derive a velocity model. In another embodiment, seismic data can be introduced into the inversion process to further refine the lower boundary parameter predictions. The process of inversion followed by seismic imaging followed by another inversion and seismic imaging step is repeated until the results of the gravity magnetics inversion and the seismic imaging processes converge to a single answer. The seismically determined velocities give an estimate of the effective stress while the inverted density model gives the overburden stress. The difference between the overburden and the effective stress is the fluid pressure. In an alternate embodiment of the invention, the method is used to obtain density models and subsurface imaging of anomalous zones such as salt bodies, shale diapirs, and extrusive or intrusive igneous bodies, where seismic data alone is unable to obtain accurate velocity estimates or do accurate imaging due to ray path distortions. The geometries and densities of these anomalous bodies are then used to generate improved overburden estimates compared to the prior art where only nearby well densities were used to constrain the overburden. For example, in the case of salt formations in the Gulf of Mexico, a top of a salt map derived from seismic imaging along with a density model and bathymetry, are utilized to produce a base of salt model from the inversion process. This may be used as input to the seismic data to obtain velocity (and effective stress) information underneath the anomalous zone.

Method for gravity and magnetic data inversion using vector and tensor data with seismic imaging and geopressure prediction for oil, gas and mineral exploration and production