Source: http://www.google.com/patents/US8151022?dq=6,219,045
Timestamp: 2014-04-17 16:50:29
Document Index: 135345093

Matched Legal Cases: ['art 510', 'art 520', 'art 510', 'art 520', 'art 510', 'art 520', 'art 520', 'art 510', 'art 520', 'art 520']

Patent US8151022 - Compression and storage of projection data in a rotatable part of a computed ... - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsA method and apparatus compress projection data and store the compressed projection data in a rotatable part that is mounted for rotation within a stationary part. The data acquisition source, compressor and storage device are connected to the rotatable part. The compressor compresses projection data...http://www.google.com/patents/US8151022?utm_source=gb-gplus-sharePatent US8151022 - Compression and storage of projection data in a rotatable part of a computed tomography systemAdvanced Patent SearchPublication numberUS8151022 B2Publication typeGrantApplication numberUS 12/352,322Publication dateApr 3, 2012Filing dateJan 12, 2009Priority dateNov 26, 2008Also published asCN102264299A, CN102264299B, CN201551325U, CN201578258U, DE112009003525T5, DE112009003532T5, US8045811, US20100128949, US20100128998, WO2010062464A2, WO2010062464A3, WO2010062465A1Publication number12352322, 352322, US 8151022 B2, US 8151022B2, US-B2-8151022, US8151022 B2, US8151022B2InventorsAlbert W. Wegener, Carl R. Crawford, Yi LingOriginal AssigneeSimplify Systems, Inc.Export CitationBiBTeX, EndNote, RefManPatent Citations (58), Non-Patent Citations (14), Classifications (16), Legal Events (2) External Links: USPTO, USPTO Assignment, EspacenetCompression and storage of projection data in a rotatable part of a computed tomography systemUS 8151022 B2Abstract A method and apparatus compress projection data and store the compressed projection data in a rotatable part that is mounted for rotation within a stationary part. The data acquisition source, compressor and storage device are connected to the rotatable part. The compressor compresses projection data samples provided by the data acquisition source to form compressed packets. The compressed packets are stored in the storage device, for example one or more solid state drives mounted on the rotatable part. A data access array contains information related to the location of the stored compressed packets. Compressed packets are retrieved and transferred across the interface to the stationary part. A decompressor at the stationary part decompresses the received compressed packets to form decompressed samples of the corresponding projection data. This abstract does not limit the scope of the invention as described in the claims.
We claim: 1. A method for data compression and storage in a rotatable part, the rotatable part mounted for rotation within a stationary part and having an interface between the stationary part and the rotatable part, wherein a plurality of sets of projection data are provided by a data acquisition source connected to the rotatable part, wherein each set of projection data corresponds to a view angle of rotation of the rotatable part and includes an array of samples acquired for a corresponding view during a data acquisition period, the method comprising:
compressing the samples of each set of projection data to form compressed samples, wherein the compressed samples for each set are arranged in at least one compressed packet, wherein each compressed packet contains the compressed samples of a corresponding portion of the projection data;
storing a plurality of the compressed packets for the plurality of sets of projection data in a storage device connected to and rotating with the rotatable part, wherein each of the compressed packets is stored at a corresponding location in the storage device that is accessible based on a packet location parameter during a controllable time period;
maintaining an access array containing a plurality of data access parameters corresponding to the plurality of compressed packets, wherein at least one index parameter is associated with the corresponding portion of the projection data for each of the plurality of compressed packets, further comprising:
generating the plurality of data access parameters based on the plurality of sizes, wherein the access array associates the data access parameter with the index parameter of the corresponding portion of the projection data;
retrieving using a data access parameter from the access array, at least one of the compressed packets from the corresponding location in the storage device in accordance with the packet location parameter in response to a data access command;
mapping the compressed packet retrieved from the storage device to at least one data transmission packet, wherein one or more data transmission packets contain the compressed samples of the compressed packet; and
transmitting the data transmission packet from a transmitter on the rotatable part to a receiver on the stationary part over a communication channel of the interface.
3. The method of claim 2, wherein the step of calculating a plurality of differences further comprises:
4. The method of claim 3, wherein the alternative difference types include a sample-by-sample difference type, a line-by-line difference type and a projection-by-projection difference type, wherein the step of calculating differences corresponding to at least two alternative difference types applies at least two of the following steps to the array of samples:
5. The method of claim 2, wherein the step of compressing further comprises attenuating the samples prior to the step of calculating a plurality of differences, the attenuating further comprising:
attenuating the samples of the array in accordance with the attenuation profile to form attenuated samples having magnitudes less than or equal to original magnitudes of the samples, wherein the step of calculating a plurality of differences is applied to the attenuated samples.
9. The method of claim 1, wherein the step of retrieving commences at a point in time after the data acquisition period.
receiving the data access command at a point in time after the data acquisition period.
receiving the data access command over a control channel of the interface.
12. The method of claim 1, wherein the step of compressing applies lossless compression or lossy compression in accordance with a compression control parameter selectable by a user.
13. The method of claim 1, wherein a compression control parameter provides an option for no compression selectable by a user, wherein the step of compressing is bypassed when the option for no compression is selected.
14. The method of claim 1, wherein the step of retrieving retrieves two or more compressed packets from the storage device, the step of mapping further comprising:
mapping two or more compressed packets to one data transmission packet.
15. An apparatus for data compression and storage in a rotatable part, the rotatable part mounted for rotation within a stationary part and having an interface between the stationary part and the rotatable part, wherein a plurality of sets of projection data are provided by a data acquisition source connected to the rotatable part, wherein each set of projection data corresponds to a view angle of rotation of the rotatable part and includes an array of samples acquired at a corresponding view during a data acquisition period, the apparatus comprising:
a compressor located on the rotatable part coupled to receive the samples from the data acquisition source, the compressor forming compressed samples arranged in at least one compressed packet for each set of projection data, wherein each compressed packet contains the compressed samples of a corresponding portion of the projection data;
an access array containing a plurality of data access parameters corresponding to the plurality of compressed packets based on sizes of the compressed packets, wherein at least one index parameter is associated with the corresponding portion of the projection data for each of the plurality of compressed packets, and the access array associates data access parameters with the at least one index parameter of the corresponding portion of the projection data;
a storage device located on the rotatable part and coupled to the compressor, wherein a plurality of the compressed packets for the plurality of sets of projection data are stored during a controllable time period, wherein each of the compressed packets is stored at a corresponding location in the storage device that is accessible based on a packet location parameter, the storage device retrieving using a data access parameter from the access array, at least one of the compressed packets stored therein in accordance with the packet location parameter in response to a data access command; and
a transmitter coupled to receive the compressed packet retrieved from the storage device, the transmitter mapping the compressed packet to at least one data transmission packet and transferring the data transmission packet over a communication channel of the interface to the stationary part.
a controller coupled to the storage device, wherein the controller provides the data access command in a format compatible with an industry standard protocol for storage device access.
17. The apparatus of claim 15, wherein the storage device responds to the data access command in accordance with an industry standard protocol for storage device access.
19. The apparatus of claim 18, wherein the compressor applies lossless or lossy compression in accordance with the compression control parameter.
20. The apparatus of claim 18, wherein the compression control parameter provides an option for no compression selectable by the user input, wherein operations of the compressor are bypassed when the option for no compression is selected.
21. The apparatus of claim 18, wherein the compression controller measures a characteristic of the compressed samples and adjusts the compression control parameter based on the measured characteristic.
a controller located on the rotatable part and connected to the storage device, the controller determining the packet location parameter of the corresponding compressed packet using one or more data access parameters in the access array in accordance with the index parameter, wherein the corresponding compressed packet is retrieved from the storage device in accordance with the packet location parameter.
23. The apparatus of claim 22, wherein the access array is stored in a memory of the controller.
24. The apparatus of claim 15, wherein the access array is stored in the storage device.
25. The apparatus of claim 15, wherein the compressor is implemented in a field programmable gate array or a programmable processor.
26. The apparatus of claim 15, wherein the compressor further comprises:
a plurality of compression modules operating in parallel, each compression module receiving a corresponding subset of the array of samples for the corresponding view and forming a corresponding subset of the compressed samples.
27. The apparatus of claim 15, wherein the storage device comprises a plurality of storage units, the apparatus further comprising:
28. The apparatus of claim 15, wherein the storage device comprises at least one solid state drive device.
29. The apparatus of claim 15, wherein the interface comprises a slip ring interface.
In a CT imaging systems, multiple x-ray radiographic views of an object produce sets of projection data. Each line of projection data represents an integration of density values of internal structures within a plane, or slice, of the object. From the multiple sets of projection data, the CT imaging system produces two-dimensional (2D) cross-sectional images and three-dimensional (3D) images of the internal structures of the object. The images are obtained through application of well-known image reconstruction algorithms to the sets of projection data. The techniques that reconstruct cross-sectional images or three-dimensional images from multiple sets of projection data are broadly referred to as �tomography�. Performing the image reconstruction using a programmable processor-based device is broadly referred to as computed (computerized or computer-assisted) tomography. In a typical application, a source of x-ray radiation projects x-rays through an object onto an x-ray sensor (or detector) array. The x-ray sensor outputs are digitized to form a set of projection data. The set of projection data can be one-dimensional or two-dimensional depending on the geometry of the detector array. Relative movement between one or more of the object, the x-ray source and the x-ray sensor array provides multiple views having different perspectives. An image of a slice through the object, or a cross-sectional image, can be approximated by the use of mathematical transforms of the multiple views. In certain applications, the cross-sectional images may be combined to form a 3D image of the object that may be otherwise unobservable.
Another application of x-ray CT is in automated inspection of industrial products. For example, cross-sectional images reconstructed from x-ray projection data are used in quality control inspection systems for manufactured products including electronic devices, such as printed circuit boards. Tomography can be used to reconstruct images of one or more planes, or cross-sections, of an object under study in order to evaluate the quality of the object. The x-ray CT system acquires sets of projection data at various locations and views with respect to the object of interest. The system architectures for industrial inspection systems differ from medical CT scanners. However, like medical CT systems, large volumes of projection data require data transfer and storage. For automated inspection systems, higher throughput of the objects under test is desirable because it reduces the cost of the product being tested. A higher throughput increases the bandwidth demands for data transfer and data storage. Another example of automated inspection using CT scanning techniques is automatic baggage screening systems.
In the U.S. Pat. No. 7,274,765 (the '765 patent) entitled �Rotating Data Transmission Device for Multiple Channels,� issued Sep. 25, 1997, Krumme et al. describe a transmission controller on the rotatable part that compresses projection data prior to conversion to serial data for transfer across the slip ring interface. A reception controller in the stationary part decompresses the compressed projection data. The '765 patent does not describe a storage device for storing compressed data on the rotatable part for later transmission to the stationary part for image reconstruction.
In the present application, �real time� applied to compression means that a digital signal is compressed at a rate that is at least as fast as the sample rate of a digital signal. The attribute �real time� can also describe rates for processing, transfer and storage of the digital signal, as compared to the original signal acquisition rate or sample rate. The sample rate is the rate at which an analog to digital converter (ADC) forms samples of a digital signal during conversion of an analog signal. The bit rate of an uncompressed sampled, or digital, signal is the number of bits per sample multiplied by the sample rate. The compression ratio is the ratio of the bit rate of the original signal samples to the bit rate of the compressed samples. For this application, real time refers to the rate at which the ADC forms the digital samples of projection data from the output signal of the x-ray sensor.
SUMMARY OF THE INVENTION Embodiments of the present invention have been made in consideration of the foregoing conventional problems. An object of the present invention is to provide a method to compress the projection data and store the compressed projection data in a rotatable part that is mounted for rotation within a stationary part and having an interface between the stationary part and the rotatable part, wherein a plurality of sets of projection data are provided by a data acquisition source connected to the rotatable part, wherein each set of projection data corresponds to a view angle of rotation of the rotatable part and includes an array of samples acquired for a corresponding view during a data acquisition period. The method comprises:
(a) compressing the samples of each set of projection data to form compressed samples, wherein the compressed samples for each set are arranged in at least one compressed packet, wherein each compressed packet contains the compressed samples of a corresponding portion of the projection data; (b) storing a plurality of the compressed packets for the plurality of sets of projection data in a storage device connected to and rotating with the rotatable part, wherein each of the compressed packets is stored at a corresponding location in the storage device that is accessible based on a packet location parameter during a controllable time period; (c) retrieving at least one of the compressed packets from the corresponding location in the storage device in accordance with the packet location parameter in response to a data access command; (d) mapping the compressed packet retrieved from the storage device to at least one data transmission packet, wherein one or more data transmission packets contain the compressed samples of the compressed packet; (e) transmitting the data transmission packet from a transmitter on the rotatable part to a receiver on the stationary part over a communication channel of the interface; and (f) extracting the compressed packet from the received data transmission packet to form a received compressed packet. Another object of the present invention is to provide an apparatus to compress and store projection data in a rotatable part that is mounted for rotation within a stationary part and having an interface between the stationary part and the rotatable part, wherein a plurality of sets of projection data are provided by a data acquisition source connected to the rotatable part, wherein each set of projection data corresponds to a view angle of rotation of the rotatable part and includes an array of samples acquired for a corresponding view during a data acquisition period. The apparatus comprises:
a compressor located on the rotatable part coupled to receive the samples from the data acquisition source, the compressor forming compressed samples arranged in at least one compressed packet for each set of projection data, wherein each compressed packet contains the compressed samples of a corresponding portion of the projection data; a storage device located on the rotatable part and coupled to the compressor, wherein a plurality of the compressed packets for the plurality of sets of projection data are stored during a controllable time period, wherein each of the compressed packets is stored at a corresponding location in the storage device that is accessible based on a packet location parameter, the storage device retrieving at least one of the compressed packets stored therein in accordance with the packet location parameter in response to a data access command; a transmitter coupled to receive the compressed packet retrieved from the storage device, the transmitter mapping the compressed packet to at least one data transmission packet and transferring the data transmission packet over a communication channel of the interface to the stationary part; and a receiver located on the stationary part coupled to receive the data transmission packet from the communication channel of the interface, the receiver extracting the compressed packet from the data transmission packet to form a received compressed packet. An advantage of the present invention is efficient storage of the compressed projection data in a storage device on the rotatable part of the slip ring.
FIG. 2 is a simplified diagram of a medical CT system including a rotatable part 510 mounted within a stationary part 520. The rotatable part 510 carries the x-ray source 100 and the DAS 130 around the object 110 being imaged to generate a set of projection data for each view angle. Depending on the array dimensions, scan protocol and the ADC resolution, the DAS 130 can generate projection data at a rate of hundreds of megabytes per second (MBps) or more. The transmitter 540 transfers the projection data across the slip ring 530 to the receiver 550 mounted in the stationary part 520, as described below. The rotatable controller 542 is disposed on and rotating with the rotatable part 510. The stationary controller 552 is disposed on the stationary part 520. The rotatable controller 542 and stationary controller 552 control data transfer operations, such as data assembly and framing. The received projection data are stored in a storage subsystem 560, such as a RAID system that includes one or more disk drives 562. The computer 570 includes an image reconstruction processor 572 to calculate a reconstructed image from the projection data. The computer 570 also includes a data access controller 574 to retrieve the projection data from the storage subsystem 560 needed for reconstruction of the image. A file of projection data for a CT scan is typically formatted with a scan header followed by samples of the projection data set for each view of the scan. The views for a given scan will produce projection data sets having the same dimensions. The projection data set for a scan can be modeled in three dimensions, where the two-dimensional projection data array represents two dimensions and the view angle, or its temporal representation, represents the third dimension. The data access controller 574 manages file access using a standard protocol, such as the protocol for serial advanced technology attachment (SATA, or serial ATA) or serial attached small computer systems interface (SAS, or serial SCSI), to retrieve the projection data samples from the storage subsystem 560. Typically, SATA and SAS disk drive interface protocols are integrated into the chipset or on the motherboard of the computer 570. In response to commands from the data access controller 574, the projection data are transferred from the storage subsystem 560 to the image reconstruction processor 572 for image formation and display 580. In alternate embodiments, rotatable controller 542 or stationary controller 552 generate requests for projection data.
Because of the complexity of the image reconstruction computations, the image reconstruction processor 572 cannot process the projection data as fast as it is generated. A typical image reconstruction processor 572 processes the projection data at a rate of about 30 to 50 MBps. Currently, image reconstruction rates in CT systems are typically two to twenty times slower than data acquisition rates. The rate mismatch between generating projection data at hundreds of megabytes per second and processing projection data at tens of megabytes per second makes it necessary to store some or all of the projection data prior to image reconstruction. The bottlenecks for transferring the projection data in the CT system of FIG. 2 are illustrated by the following example. Assume that DAS 130 includes an array with dimensions of 100 rows with 1000 sensors per row and 2 bytes per sample. Each view generates 200 kilobytes (kB) of projection data. When the CT scanner measures 3,000 views per second, the DAS 130 outputs projection samples at a rate of 600 megabytes per second (MBps). Typically, the transmitter 540 applies 8 bit/10 bit (8B10B) encoding or 4 bit/5 bit (4B5B) encoding to the projection data prior to transfer across the slip ring 530, so that each byte of data is represented by ten bits during the transfer. For projection data generated at 600 MBps, the slip ring 530 must be capable of data transfer at a rate of at least 6 Gbps. The slip ring 530 is the first bottleneck for transport of the projection data. At the stationary part 520, the 600 MBps of projection data are transferred to the storage subsystem 560. Access to the storage subsystem 560 at a rate of at least 600 MBps for writing the projection data is the second bottleneck. The computer 570 retrieves projection data needed for reconstruction of the image at a rate of 30 MBps, which is twenty times slower than the rate of data acquisition, creating the third bottleneck. Increases in sensor array dimensions and number of view angles per scan will require greater data transfer rate and storage capacity, increasing the cost of the system.
The communication channel of the slip ring interface 530 includes one or more physical transmission channels. The physical channels can provide electrical, optical or RF transmission of projection data from the rotatable part 510 to the stationary part 520. For optical transmission, an electro-optical transducer, such as a laser diode, converts the electrical signal representing the samples to an optical signal carried via optical fiber to the slip ring interface 530 for transmission. An optical receiver on stationary part 520 includes a photodiode to convert the optical signal to an electrical signal representing the received samples. Currently an optical link provides a bandwidth of 2.5 Gbps. For an electrical transmission channel on a slip ring 530, an electrically conductive strip, or ring, usually on the rotating part is in close proximity to a secondary electrically conductive strip on the stationary part. Capacitive coupling across the small air gap between the two electrically conductive strips or rings together comprise a capacitively coupled transmission channel. Common transmission rates per capacitively coupled channel are 2 to 6 Gbps. To achieve higher data rates, multiple optical or capacitively coupled transfer units are arranged in parallel on the rotatable part and the stationary part.
Calculate difference: e_diff = n_exp(i) − n_exp(i − 1)
Encode e_diff as follows:
mean ⁡ ( 2 ) = mean ⁡ ( 1 ) + r ( 14 ) ⁢ = [ Y ⁢ ⁢ max ⁡ ( 1 ) + Y ⁢ ⁢ min ⁡ ( 1 ) + 2 ⁢ ⁢ r ] / 2. ( 15 ) Equation 15 shows three alternatives for adjusting Ymax and/or Ymin to increase the mean by an amount r:
1) Set Ymax(2)=Ymax(1)+2r and Ymin(2)=Ymin(1); (16a)2) Set Ymax(2)=Ymax(1)+r and Ymin(2)=Ymin(1)+r; (16b)3) Set Ymax(2)=Ymax(1) and Ymin(2)=Ymin(1)+2r; (16c)
The compressed packets resulting from a single scan can be stored in one or more files in storage device 502. For this description, it is assumed that all the compressed packets produced for one scan are stored in a single file. The storage device 502 can store the compressed data file for the scan until a command is received to access the compressed data. The storage device 502 can respond to a command to provide the compressed data on demand for image reconstruction processing. The compressed data can be retrieved and transferred across the slip ring interface 530 at a rate that supports the image reconstruction processing. For the example describe above, the data transfer rate for supporting image reconstruction processing is 30 MBps. Alternatively, the storage device 502 can respond to a command to provide the compressed data to a stationary storage device at a data transfer rate that accommodates the write speed of the stationary storage device. The user can determine the period of time that the compressed data for the scan is stored in the storage device 502 and the destination of the retrieved compressed data.
The transmitter 540 transmits the retrieved compressed packets across the slip ring interface 530 to the receiver 550. The implementations of the transmitter 540 may include the formation of data transmission packets. One implementation of data transmission packets is described by Popescu et al. in the U.S. Patent Application Publication entitled �Method and Device for Data Transmission between Two Components Moving Relative to One Another,� publication number US 2008/0205446, Aug. 28, 2008. The rotatable controller 542 or other processer associated with the transmitter 540 inserts the compressed packets, including compressed packet headers, into the data portion of the data transmission packet. The mapping of the compressed packets to the data transmission packets depends on the format parameters of the data transmission packet. FIG. 11 shows alternative mapping schemes for the compressed packets to form the data transmission packets. The data transmission packets each include a header portion, indicated by �H�, and a footer portion, indicated by �F�. An example of the header portion includes fields for synchronization (sync) data and transmission packet identification. An example of the footer portion includes fields for forward error correction (FEC) and cyclic redundancy check (CRC). In one alternative mapping, the compressed packet Pi is divided and inserted into the data portions of multiple data transmission packets, Ti1 and Ti2. In another alternative mapping, the entire compressed packet Pj is inserted into the data portion of a single data transmission packet Tj. In another alternative, multiple compressed packets P1 to PN are combined and inserted into a single data transmission packet TN. The transmitter 540 can apply 8 B10 B or similar encoding to the data transmission packets prior to transfer over the slip ring interface 530. The receiver 550 can apply 8 B10 B or similar decoding of the data transmission packets. The stationary controller 552 or other processor associated with the receiver 550 can extract the compressed packets from the data portion of the received data transmission packets and reassemble the sequence of compressed packets.
1) For each view, SerDes 602 transmits rows 1 to 50 and SerDes 604 transmits rows 51 to 100; 2) For all 100 rows in a view, SerDes 602 transmits sensor values 1 to 500 and SerDes 604 transmits sensor values 501 to 1000; 3) For each view, SerDes 602 transmits odd-numbered rows and SerDes 604 transmits even-numbered rows; or 4) SerDes 602 transmits the projection data for odd-numbered views while SerDes 604 transmits even-numbered views. The FPGA input SerDes transceivers 610 and 612 deserialize and apply 8B10B decoding to the data streams to regenerate the respective sequences of projection data samples. The compression modules 620 and 622 operate in parallel on separate input sample streams to produce the compressed samples for each input data stream at the sample rate of the DAS 130. For example, suppose that the DAS 130 produces projection data samples at 400 Msps to both SerDes transceivers 602 and 604 and that each compression module 620 and 622 has a processing rate of 200 Msps. The compression modules 620 and 622 operating in parallel process the projection data samples at 400 Msps, or in real time. The compressed sample streams output from the compression modules 620 and 622 are each divided to match the write access bandwidth of the SSDs. For example, suppose the SSDs each have a write access bandwidth of 100 MBps and the original projection data samples have two bytes per sample. In this case, the compression modules 620 and 622 each provide a compression ratio of 2:1 to produce compressed sample streams at a rate of 200 MBps. The bandwidth of the compressed samples must be divided in half to accommodate the limited write access bandwidth of the SSD. The demultiplexers 630 and 632 divide the respective streams of compressed samples for storage in the storage modules SSD1, SSD2, SSD3 and SSD4 in accordance with control information from the executive controller 640. Preferably, each demultiplexer 630 and 632 divides the respective compressed samples on packet boundaries so that an entire compressed packet is stored in a single SSD. For example, the demultiplexer 630 can direct alternate packets to SSD1 and SSD2 in a ping-pong arrangement. The SATA controllers C1, C2, C3 and C4 manage the storage and retrieval of data in accordance with the SATA protocol.
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No. 12/208,839 entitled "Adaptive Compression of Computed Tomography Projection Data," filed on Sep. 11, 2008, 36 pages.14Young, Susan S., et al., "Statistically lossless image compression for CR and DR," SPIE Vo. 3658, Feb. 1999, 406-419.Classifications U.S. Classification710/68, 382/248, 382/232, 382/239International ClassificationG06K9/36, G06F13/38, G06F13/12, G06K9/46Cooperative ClassificationH04N19/00187, H04N19/0026, H04N19/00369, G06T9/00European ClassificationH04N7/26A4P, H04N7/26J2, H04N7/26A8R, H04N7/26A6E4GLegal EventsDateCodeEventDescriptionFeb 8, 2014ASAssignmentFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SAMPLIFY SYSTEMS, INC.;REEL/FRAME:032177/0872Owner name: MOOG INC., NEW YORKEffective date: 20131216Jan 12, 2009ASAssignmentOwner name: SAMPLIFY SYSTEMS, INC., CALIFORNIAFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WEGENER, ALBERT W.;CRAWFORD, CARL R.;LING, YI;SIGNING DATES FROM 20081224 TO 20090104;REEL/FRAME:022093/0182RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google