Exemplary embodiments are directed to wireless power devices. A device may include a transmit antenna and a metallic structure spaced from and configured for detuning the transmit antenna. The device may further include a circuit for tuning the transmit antenna.

1. Field
The present invention relates generally to wireless power, and more specifically, to a wireless power device for transmitting wireless power.
2. Background
Approaches are being developed that use over the air power transmission between a transmitter and the device to be charged. These generally fall into two categories. One is based on the coupling of plane wave radiation (also called far-field radiation) between a transmit antenna and receive antenna on the device to be charged which collects the radiated power and rectifies it for charging the battery. Antennas are generally of resonant length in order to improve the coupling efficiency. This approach suffers from the fact that the power coupling falls off quickly with distance between the antennas. So charging over reasonable distances (e.g., >1-2 m) becomes difficult. Additionally, since the system radiates plane waves, unintentional radiation can interfere with other systems if not properly controlled through filtering.
Other approaches are based on inductive coupling between a transmit antenna embedded, for example, in a "charging" mat or surface and a receive antenna plus rectifying circuit embedded in the host device to be charged. This approach has the disadvantage that the spacing between transmit and receive antennas must be very close (e.g. mms). Though this approach does have the capability to simultaneously charge multiple devices in the same area, this area is typically small, hence the user must locate the devices to a specific area.
As will be appreciated by a person having ordinary skill in the art, a transmit antenna of a wireless power device may be detuned by an external metal structure, which is positioned proximate the transmit antenna. Accordingly, the efficiency of wireless power transfer between the wireless power device and a receiver may be decreased. A need exists for methods, systems, and devices for enhanced wireless power transfer. More specifically, a need exists for methods, systems, and devices for a wireless power device with enhanced immunity to detuning caused by external structures.


An embodiment in accordance with the present invention enables storing in a memory, multi-bit data corresponding to analog signals read from a medium before being converted to single-bit data as recorded data. In an embodiment of the present invention, an AD converter is configured to convert analog signals from a magnetic disk to multi-bit data. A buffer circuit holds successively multi-bit data transferred from the AD converter toward a Viterbi decoder, and outputs the held plural multi-bit data in parallel. A SRAM for ECC is used for storing multi-bit data transferred from the buffer circuit.

Embodiments in accordance with the present invention relate to a media drive apparatus and a control circuit for a media drive apparatus. In particular, embodiments in accordance with the present invention relate to a technique to store a multi-bit data corresponding to signals read from a medium before converting it to a single bit data as a recorded data.
Medium drive apparatuses using various medium such as an optical disk, a magnetic tape, and a flexible magnetic disk are known in the art. In particular, a hard disk drive (HDD) has been widely used as a storage device of a computer. The HDD is one of indispensable storage devices for current computer systems. The HDD has found widespread application such as a removable memory used in a moving image recording/reproducing apparatus, a car navigation system, a cell phone, or a digital camera, in addition to the computer, due to its outstanding characteristics.
A magnetic disk in the HDD has plural concentric data tracks, each of which records plural servo data including address information and plural data sectors. A head element accesses to a desired data sector based on address information of the servo data, making it possible to write/read data to/from the data sector.
An AD converter in a channel circuit converts analog signals from the head element to multi-bit data. The multi-bit data from the AD converter are processed by a digital FIR filter and then converted to single bit data by a decoder. The single bit data are the data recorded on the magnetic disk.
It has been previously known to hold the output of the AD converter in the channel circuit and use it for an error recovery process or circuit design of a HDD. For example, Japanese Unexamined Patent Application Publication No. 2000-105901 discloses use of multi-bit data stored in a memory in a retry process for a read error. Specifically, waveform samples from an AD converter operation are stored in a memory in a channel circuit. If an ECC process is not capable of correcting user data, the HDD obtains the waveform data stored in the memory in the channel circuit and retry the subsequent process of read data.
Use of waveform data of one sector as disclosed in the above prior art document enables to re-decode the read data without accessing to the data on the magnetic disk. The technique of the above prior art reference, however, has some possible disadvantages. For one thing, the memory in the channel circuit dedicated to storing the AD converter output values increases the circuit area.
The technique of the prior art reference also has an issue regarding the transmission speed. In a typical HDD, the data transfer rate in the channel circuit is about 1 Gbit/s. This transfer rate is for the decoded single bit data, and the total amount of the AD converted data is a multiple of the bit number of the AD conversion. A typical bits of the AD conversion is 6-bit, therefore the transfer rate for storing the AD converted data is about 6 Gbit/s. A high performance memory may be necessary to store data of such a high transfer rate, resulting in higher demands on the circuit performance and higher cost.

Storing AD sampled data of read/write channel into ECC SRAM

Hitachi Global Storage Technologies Netherlands B.V.


In manufacturing a helical antenna, use is made of a cylindrical member having a peripheral surface. A helical conductor is attached to the peripheral surface and extends along the peripheral surface to make a helical fashion. The helical conductor may be obtained as follows. At first, a mask layer is formed on the peripheral surface of the cylindrical member with a helical gap left therein. Metal particles are attached onto the mask layer and onto the peripheral surface through the helical gap. Next, the mask layer is detached from the outer peripheral surface of the cylindrical member while the metal particles are left as the helical conductor on the outer peripheral surface.

This invention relates to a digital radio receiver for receiving a radio wave from an artificial satellite (which may be called a xe2x80x9csatellite wavexe2x80x9d) or a radio wave from a ground station (which may be called a xe2x80x9cground wavexe2x80x9d) to listen to digital radio broadcasting and, in particular, to an antenna for use in the digital radio receiver as well as a method of producing the antenna.
In recent years, a digital radio receiver for receiving a satellite wave from an artificial satellite or a ground wave from a ground station to listen to digital radio broadcasting has been developed and is put into practical use in the United States of America. The digital radio receiver is mounted on a mobile station such as a vehicle and is adapted to receive a radio wave having a frequency of about 2.3 GHz to listen to the digital radio broadcasting. In other words, the digital radio receiver is a radio receiver capable of listening to mobile broadcasting. It is noted here that the ground wave is a radio wave obtained by slightly shifting the frequency of the satellite wave after it is received by the ground station.
In order to receive the radio wave having the frequency of about 2.3 GHz, it is necessary to mount an antenna at a position outside the vehicle. Such antenna may have various structures but a stick type is generally used rather than a planar type (flat type). As well known, an electromagnetic wave emitted into a free space is a transversal wave having an electric field and a magnetic field vibrating in a plane perpendicular to a propagating direction of the wave. The electric field and the magnetic field are variable in intensity within the above-mentioned plane. Such electromagnetic wave in which the direction of the electric field is not random but constant or varied in some regular way is referred to as a polarized wave. The satellite wave is a circular polarized wave exhibiting circular polarization while the ground wave is a linear polarized wave exhibiting linear polarization.
Hereinafter, description will mainly be made of an antenna for receiving the satellite wave. As one of stick-type antennas, a helical antenna is known. The helical antenna comprises a hollow or solid cylindrical member and a conductor wire wound around the cylindrical member in a helical fashion and can efficiently receive the above-mentioned circular polarized wave. Therefore, the helical antenna is exclusively or mainly used to receive the satellite wave.
An existing helical antenna is produced by preparing a cylindrical member or a pole, forming an antenna pattern on a flexible substrate to obtain a patterned film, and winding the patterned film on the cylindrical member or the pole.
However, the helical antenna comprising the patterned film wound around the cylindrical member or the pole is complicated in structure, resulting in a bar to reduction in cost.
It is therefore an object of this invention to provide a helical antenna which is further simplified in structure and is reduced in cost.
It is another object of this invention to provide a method of producing the above-mentioned helical antenna.
Other objects of the present invention will become clear as the description proceeds.
According to the present invention, there is provided a helical antenna comprising a cylindrical member having a peripheral surface and a helical conductor attached to said peripheral surface and extending along said peripheral surface to make a helical fashion.
According to the present invention, there is provided a method of producing the helical antenna. The method comprises the steps of preparing the cylindrical member, forming a mask layer on the peripheral surface of the cylindrical member with a helical gap left in the mask layer, attaching metal particles onto the mask layer and onto the peripheral surface through the helical gap, and detaching the mask layer from the peripheral surface with the metal particles left as the helical conductor on the outer peripheral surface.
According to the present invention, there is provided a method of producing the helical antenna. The method comprises the steps of preparing the cylindrical member, forming a conductor layer on the peripheral surface of the cylindrical member, forming a mask layer on the conductor layer with a helical gap left in the mask layer, forming a metal plating layer on the conductor layer through the helical gap, and removing, with the metal particles left as the helical conductor on the outer peripheral surface, from the peripheral surface the mask layer and a masked part of the conductor layer which is covered with the mask layer.

Simple helical antenna and method of producing the same


A gas or diesel internal combustion engine of either a two or four stroke design uses both ends of each piston to create a combustion chamber. The piston rod rides linearly through a lower cylinder head. The lower cylinder head forms a lower combustion chamber with its own set of valves and fuel/air inlet. A second set of lower cams and camshaft operate the lower set of valves. Crankcase oil is pumped up the middle of the piston rod to an outlet in the center of the piston.

With fuel economy a global issue for all motor vehicles, any weight reduction for the engine would increase the fuel economy. It is also desirable to reduce wear and tear on the piston, the cylinder and the piston rod with a linear movement of the piston rod. See U.S. Pat. No. 5,158,046 (1992) to Rucker. Rucker's FIG. 5 shows a two piston opposed cylinder engine with linear movement of the two piston rods.
The present invention offers the power of two pistons with each piston by firing a power stroke from both the top and bottom of each piston. The power of an eight cylinder engine can be derived from the cylinder block of a four in line cylinder block. Linear piston rod movement reduces wear and tear.


In some embodiments, an apparatus and a system, as well as a method and an article, may operate to receive down hole tool environmental temperature data, axial temperature data, radial temperature data, and log data. Further activity may include applying temperature effects compensation associated with the environmental temperature data and the down hole log data using a fitting function model obtained from a trained neural network to transform the down hole log data into corrected log data. Additional apparatus, systems, and methods are described.

Understanding the structure and properties of geological formations can reduce the cost of drilling wells for oil and gas exploration. Measurements made in a borehole (i.e., down hole measurements) are typically performed to attain this understanding, to identify the composition and distribution of material that surrounds the measurement device down hole. To obtain such measurements, a variety of sensors are used. Since borehole temperature, which varies widely, can significantly affect the operation of such sensors, it is sometimes useful to adjust down hole logging data to improve measurement accuracy.

Temperature compensation apparatus, methods, and systems


A direct spread spectrum communication system in accordance with a delayed multiplex mode in which improvement in correlation and improvement in error rate can be perfectly realized in any data length. A data generating section appends addition bits so as to generate an integral multiple of information to be transmitted, from data received from an upper (MAC) layer. The symbol length of a data part is determined from information obtained from the upper layer, and the generating section knows the symbol length of a bit synchronization section, a frame synchronization section and a various information section in the system, which should be originally appended as a packet. Therefore, the number of additional bits are added so that the total number of symbols amounts to an integral multiple of the data to be multiplexed.

The present invention relates to a spread spectrum communication and more particularly to a spread spectrum communication system conforming to a delayed multiplex mode transmission, and a method of communication using the system.
Spread spectrum communication systems have recently been developed, and have attracted a great deal of public attention as a new and interesting communication method. A typical modulation system used in conventional data communication systems is a narrow band modulation system which can be realized by relatively small circuitry, but which is weak to interference such as multipath interference and narrow band color noises. Such may occur indoors in offices and workplaces. On the contrary, the spread spectrum communication system is free from the above-mentioned problem since it can spread a data spectrum with a spread code and transmit the spread-spectrum coded data in a wide band.
The spread spectrum communication system, however, has a disadvantage of requiring a widened bandwidth to transmit data at a high speed. For example, a bandwidth of 22 MHz is required to realize spread-spectrum transmission of QPSK (Quadrature Phase Shift Keying) modulated data with 11 chips of spread code at a transmission rate of 2 Mbps. Namely, the bandwidth of 110 MHz is needed to transmit data at 10 Mbps. The fact that radio transmission has a restriction on bandwidth makes it more difficult to realize the high-speed data transmission by the spread-spectrum communication method.
Accordingly, a method for multiplexing spectrum signals with a delay (hereinafter called xe2x80x9cDelayed multiplex systemxe2x80x9d) has been proposed as a method of transmitting data within a limited bandwidth at a high speed, which is described in Japanese Patent Application No. 7-206159.
The use of this method can increase the data transmission rate within a limited bandwidth. For example, the data transmission rate 2 Mbps at 22 MHz (as described before) can be increased to 4 Mbps by multiplexing the data twice and further to 10 Mbps by multiplexing the data five times.
FIG. 6 shows a typical block diagram of a conventional system used for proposed delayed multiplex transmission method. In FIG. 6, data generated by a data generating section 10 is differentially coded by a differential coding section 11 and then converted to parallel sets of data to be multiplexed by a series-to-parallel (S/P) converting section 12. The parallel data sets are transferred to respective multiplying sections (13-1xcx9c13-5) whereby they are spread by multiplying by a PN code received from a PN generator 14. Then, the parallel data sets are delayed respectively by the delay elements (15-1xcx9c15-5).
The delayed parallel data sets are combined by a frequency combining section 17 to form multivalued digital signals which are then modulated with oscillation of an oscillator 18 by a modulator 17 and transmitted through a frequency converter 19 and a power amplifier 20.
The high-speed data transmission within the limited bandwidth is thus accomplished.
However, the delayed multiplex data transmission still encounters an increase in error rate from interference between multiplexed signals.
Accordingly, the inventor of the present application also proposed a method for improving the correlation and error rate for the delayed multiplex transmission (Japanese Patent Application No. 8-13963).
FIG. 7 shows a typical circuit diagram of a conventional delayed multiplex system by which improvement in error rate has been realized. This example is described below. The transmission system is the same with the system shown before in FIG. 6. In the receiving system of FIG. 7, a received frequency signal is converted to a base band signal by a frequency converting section 21 and correlated by a correlator 23. The correlation is latched by a latch section 24 at the timing of a correlating spike and, then, is recovered from the deterioration due to auto-correlation by a correlation processing section 25. This correlation output is distributed by a distributor 26. The signal is controlled by a latch controller 29 and latched by latch sections 27 and 28. According to the aforementioned actual example, the signal is latched with 2 chips or 3 chips.
The signal is differentiated by a differential section 30 and discriminated and demodulated by a discriminating section 31.
FIG. 8 is a typical construction block diagram of the correlating processing section of FIG. 7. This depicts a five-multiplex case. In FIG. 8, there is shown only one line that must be doubled for realizing the system of FIG. 7.
An input signal is input to shift registers 25S corresponding to the number of input bits. The registers hold correlation spikes by four before and after a desired demodulation timing spike. An arithmetic unit 25P with a selecting function carries-out operations on the signals at a timing signal generated by a timing signal generator 25T which matches the timings of input and output according to signals from a correlation synchronizing circuit (not shown in FIG. 8).
FIG. 9 is a block diagram showing a typical internal construction of the arithmetic unit with a selecting function, which is shown in FIG. 8.
The use of the unit of FIG. 9 can considerably decrease a change in amplitude of a signal due to the influence of an auto-correlation side-lobe, and can therefore make a great improvement in error rate. The operation of this unit is as follows:
As seen in FIG. 9, signals A and F are input to a selector 25P1, signals B and G are input to a selector 25P2, signals C and H are input to a selector 25P3 and signals D and I are input to a selector 25P4. In this instance, the selectors 25P1-25P4 select signals A, B, C and D respectively. The selected signals A-D are added together by an adder 25P5 and then divided by 11 by a divider 25P6. The resultant signal is added to Exe2x80x2 by an adder-subtracter 25P9, then latched by a latching section 25P8 and output.
In the example shown, preceding and proceeding correlation signals are used for improvement of the correlation output. When received signals are 5-multiplex signals, each signal is composed of five blocks and five correlatin outputs are used for improvement in correlation. However, five blocks cannot be obtained due to the transmitted data length.
FIG. 10 is a conceptual illustration of an exemplified state of five-multiple data. In the case shown, there is no data in the two last blocks (i.e., the two last symbols are lost) since these signals, (outputs of respective delay elements) before being multiplexed, do not have the data length of a multiple of 5. Consequently, data consisting of 128 symbols is divided into 5 groups, each consisting of 5 blocks of 5 symbols, and thus 3 symbols remain, as shown in FIG. 10. In this instance, the conventional correlation-improved circuit cannot exert a sufficient effect of improving the correlation because blocks of coded signals are partly omitted. Thus, an error rate for the last three symbols worsens. In packet communication, 1 bit error causes retransmission of data. Therefore, an increase in error rate for above-mentioned symbols decreases the throughput of the packet transmission system.
In view of the above-mentioned problems, the present invention was made to provide a direct spread spectrum communication system conforming to a delayed multiplex mode transmission and a communication method using the system, which can realize improvement in correlation and improvement in error rate in any data length by applying the above mentioned technical means featuring the present invention.
(1) In view of the above-mentioned problems, the present invention was made to provide a direct spread spectrum communication system conforming to a delayed multiplex mode transmission and a communication method using the system, which can realize improvement in correlation and improvement in error rate in any data length by applying the above mentioned technical means featuring the present invention.
(2) Another object of the present invention is a direct spread spectrum communication system conforming to a delayed multiplex mode as defined in above item (1), which is featured in that the system is further provided with means adapted for transmitting and receiving a simplex signal directly spread with a spread code.
(3) Another object of the present invention is to provide a direct spread spectrum communication system conforming to a delayed multiplex mode as defined in any of above items (1) and (2), which is featured in that the means are adapted to cause the number of additional bits to be an integer multiple of the multiplex number multiplied by the number of bits composing a unit to be processed by the system.
(4) Another object of the present invention is to provide a direct spread spectrum communication system conforming to a delayed multiplex mode for transmitting and receiving a plurality of series of signals directly spread by using a spread code and multiplexed by using multiplexing means for multiplexing signals at a delay time of any desired number of chip codes, which is further provided with means for appending an additional bit or bits before the start of a multiplex section following to a simplex section in a signal format for setting signals to be transmitted and received in a simplex mode and a multiplex mode.
(5) Another object of the present invention is to provide a communication method using any one of the direct spread spectrum communication systems mentioned above items (2) to (4) conforming to a delayed multiplex mode, which method is featured in that a length of additional bits to be inserted is set to a length corresponding to a transit period during which the operation of the system is unstable after switching the transmission mode from the simplex mode to the multiplex mode can be stabilized.
(6) Another object of the present invention is to provide a communication method, using any one of the direct spread spectrum communication systems mentioned above item (2) conforming to a delayed multiplex mode, which is featured in that an additional bit or bits having no relation to transmissive data are inserted before the start of a multiplex section following to a simplex section in a signal format for setting signals to be transmitted and received in a simplex mode and a multiplex mode.
(7) Another object of the present invention is to provide a communication method, using any one of the direct spread spectrum communication systems mentioned above items (5) and (6) conforming to a delayed multiplex mode, which is featured in that error correction such as convolutional coding in the multiplex section is applied to a format of data to be transmitted in the multiplex mode according to the signal format in such a way that the appendable additional bit or bits are given specific data according to the error correction scheme to use for training of error correction processing.
(8) Another object of the present invention is to provide a communication method, using any one of the direct spread spectrum communication systems mentioned above items (5) to (7) conforming to a delayed multiplex mode, which is characterized in that the system uses a specific data format that allows error checking such as CRC to be conducted on only the data omitting the additional bit or bits appended thereto.
(9) Another object of the present invention is to provide a communication method, using any one of the direct spread spectrum communication systems mentioned above items (5) to (8) conforming to a delayed multiplex mode, characterized in that the number of additional bits is an integer multiple of the multiplex number multiplied by the number of bits composing a unit to be processed by the system.
In the communication system according to the present invention, every packet may contain complete blocks with no omitted symbol, even in the last section thereof, by appending additional bits so as to form a packet consisting of, e.g., five blocks when the number of multiplexed signals is 5. This may solve the problem of increasing an error rate due to lack of or omission of a last symbol when multiplexing signals, which is required in prior art systems.
In the communication system for transmitting data having a simplex section and multiplex section, the transmission error rate of the whole system and the packet throughput of the system can be improved by selectively appending additional bits to the multiplex sections.
The additional bits interposed between a simplex section and a multiplexed section can prevent the transmit data from being affected by the unstable operations of digital and analog circuits during a transitional period after switching from a simplex section to a multiplexed section, consequently increasing the throughput of the communication system of the present invention. In detail, the additional bit section is placed between a simplex section and a multiplexed section in such a way that {circle around (1)} the number of the bits included the additional bit section corresponds to a time longer than that required for stabilizing the operation of the system (i.e., the length of transitional section plus the unstable section) and {circle around (2)} a total number of added symbols (bits) and symbols in the multiplexed section is an integer multiple of the multiplex number. The data format thus defined enables the additional bits to protect data against the influence of unstable period of the system and improve the transmission error rate of the system due to a lacking of a block.
The content of additional bits is controlled so as to cause the bits to function as the preprocessed section for convolutional coding of the data. Thus, the transmit data from the head (effective bit) can be effectively corrected for possible error in the format when conducting error correction with the convolutional codes.
CRC (Cyclic Redundancy Checking) can be conducted on only the effective data, omitting the additional bits and the calculation with the additional bits. This assures effective error detection and the improved throughput of the whole system.
The number of additional bits is selected to be equal to a common multiple of the multiplex number and a unit of bits (e.g., 8 bits) to be processed by the system, whereby the transmission length can be represented in a byte unit. Thus, calculation using fractions is not needed, thereby facilitating communication processing.

Direct spread spectrum communication system corresponding to delayed multiplex mode, and method of communication using the system


A column-mounted shift control assembly includes a gate and mounting bracket, a shift lever unit rotatably mounted on the bracket, a shift handle pivotally mounted on the shift lever unit, and resilient means for urging the terminal end of the shift handle toward the bracket. The latter includes a planar gate portion having detents formed on an edge thereof for selective cooperation with the shift handle terminal end to select a desired transmission shift position. An ignition interlock mechanism cooperates with the terminal end of the shift handle to prevent its movement out of the Park detent position unless the ignition switch key is turned on, and further prevents the ignition switch from being turned back to Lock unless the terminal end is in Park position, thus preventing key extraction.

A known ignition interlock mechanism for a column-mounted shift control assembly is disclosed in Dzioba U.S. Pat. No. 4,821,605. This mechanism includes a latch plate pivotally mounted on an end of an arcuate shaped detent plate. The latch plate has a locking surface which is selectively positioned via the interaction of a key cylinder slot, a lock pin, a ramped plunger, and a cable to prevent removal of an operator lever positioning arm from the Park position prior to the key cylinder being unlocked. The latch plate also includes a positioning surface which, when engaged by the positioning arm upon its return to Park position, will pivot the latch plate to thereby move the plunger and permit the lock pin to leave the key cylinder slot and permit the key to be returned to its lock and remove position.

Ignition interlock mechanism for a column-mounted shift control assembly


An insulating wafer-storing container for storing substrates inside the container is provided in which at least one exterior surface of the container is formed with a contact portion that is to be in contact with an object other than the container and a non-contact portion that is not to be in contact with the object when the object is brought into contact with the at least one exterior surface, and the area of the contact portion is 40% or less of the total of the area of the contact portion and the area of the non-contact portion.

In semiconductor wafer handling steps such as steps of cleaning, drying, testing, heat treatment, and CVD processing for wafers among the semiconductor wafer production processes and the subsequent semiconductor device production processes, wafers are carried in a state of being stored in a wafer-storing container (also referred to as a "cassette case"). Particularly in a sheet-fed-type wafer processing apparatus, after the container is located at a predetermined position, wafers are taken out one by one from the container using a robot or the like and various processes are performed. As disclosed in Patent Document 1, a typical wafer-storing container is formed by molding an insulating plastic such as polycarbonate (PC) or polyether ether ketone (PEEK) as a whole and comprises a box-shaped container main body that is opened at one side surface, a rack for holding wafers that is fixed in the container main body, and a lid body that is detachably attached to the opening part of the container main body.


A snare drum including a drum shell having an upper head and a lower head mounted thereon and a frame for holding a plurality of snare wires. The frame arranges the snare wires to be in contact with the lower head or to be spaced from the lower head. The snare drum includes a first latched member and a second latched member respectively located at opposite ends of the frame at an outer side the drum shell. An attachment mechanism is located on the drum shell for arranging the frame on a surface of the lower head. The attachment mechanism includes a first latching member and a second latching member arranged between the drum shell and the first and second latched members for separably latching the first and second latched members, respectively.

The present invention relates to a snare drum, and more particularly, to a snare drum of a type having a plurality of snare wires held by a frame.
A snare drum having a plurality of snare wires on a lower head face is known in the prior art (see U.S. Pat. No. 1,832,227).
FIG. 19 is a perspective view showing a snare wire unit 211 of a first prior art example. FIG. 20 is a view of a snare drum 200 to which the snare wire unit 211 is attached, as seen from the lower side of the drum 200. As shown in FIG. 19, the snare wire unit 211 has a plurality of snare wires 201, and a right metal holder 202 and a left metal holder 203 for holding opposite ends of the snare wires 201. In the prior art snare drum 200, the metal holders 202 and 203 are respectively inserted into and fastened to a right connector 205 and a left connector 206, which are located on a lower hoop 204 of the drum 200. The right connector 205 has an opening in its right face so that the snare wire unit 211 can be inserted into and removed out through the opening. A threaded hole (not shown) is formed in the left face of the left metal holder 203. A bolt 207 provided in the left connector 206 is engaged with the threaded hole to fasten the left metal holder 203 and the left connector 206 together to each other. Further, a switch 210 is connected to the left connector 206 for bringing the snare wires 201 close to the lower head 209.
To remove the snare wire unit 211 from the snare drum 200, the bolt 207 is first loosened and the left metal holder 203 is pulled in the rightward direction out of the left connector 206. The right metal holder 202 is then pulled in the rightward direction out of the right connector 205. To attach the snare wire unit 211 to the snare drum 200, the left metal holder 203 is first inserted through the right connector 205 from the right side to the left side. Then, the left metal holder 203 is inserted into the left connector 206 from the right side to the left side. The bolt 207 is then tightened to fasten the left metal holder 203 to the left connector 206. This also fastens the right metal holder 202 to the right connector 205 The snare wire unit 211 is attached to the snare drum 200 in this manner.
There is a second prior art example, in which snare wires are held by a frame and the frame is supported by a string on the drum (see U.S. Pat. No. 3,113,481). To remove a snare wire unit, which includes a plurality of snare wires and the frame, from the snare drum, the string is first loosened. Then, the unit is detached from the drum.
Detachment and attachment of the snare wire unit becomes necessary when replacing, for example, a lower head or individual snare wires. In the first and second prior art examples, however, a series of tasks as described above must be performed to detach and attach the snare wire unit. These tasks are complicated and troublesome.
Further, in the first prior art example, once the snare wire unit 211 is removed, the tension of the snare wires 201 drops to zero. This means that the adjusted tension before detachment of the snare wire unit 211 cannot be maintained. Thus, tension adjustment must be performed again after the attachment. It is inefficient and troublesome to perform tension adjustment every time the snare wire unit is detached and attached. Moreover, since the fastening with the bolt 207 of the left connector 206 applies tension to the snare wires 201 in addition to fixing the left metal holder 203 to the left connector 206, the tension of the snare wires 201 is directly applied to the switch 210 and the body of the drum 200. This results in various problems, such as much strength being required to operate the switch 210 and deformation of the drum body occurring.
Further, the opposite ends of the plurality of snare wires 201 are all fixed to the metal holders 202 and 203 so that the snare wires 201 do not become scattered when the snare wire unit 211 is detached from the drum. Therefore, the snare wires cannot be replaced individually. The number of the snare wires is usually about ten to fourteen. However, when there is no need to use, for example, four to eight snare wires, the unnecessary snare wires must be cut off. However, once the wires are cut off, it is impossible to restore the cut off wires when the original number of snare wires becomes necessary.
The second prior art example differs from the first prior art example in that the snare wires are held by the frame and the tension of the snare wires is thus maintained even after detachment of the snare wire unit. However, the string fastens the frame to the drum. Thus, it is difficult to adjust the position of the string accurately. Consequently, there is a problem in that a slight difference in the position of the snare wire unit before and after the detachment occurs. Further, especially when the snare drum is used as a marching snare drum, there is a problem in that the string is often broken due to heavy vertical and horizontal swaying motions during usage of the drum.
It is an object of the present invention to provide a snare drum which eliminates the need for tension adjustment when reattaching snare wires which have been detached and which simplifies the attachment and detachment of snare wires to a drum. A further object of the present invention is to provide a snare drum that enables snare wires to be replaced individually.


A magnetic field source that produces a stepped field of greater magnitude than the remanence of the magnetic material used to construct it. The source is basically a magnetic igloo comprised of two hemispheres having different cavity flux value that are separated by a passive ferromagnet slab. The hemispheres are positioned such that they share the same radial center point. The slab has a predetermined thickness and a tunnel of predetermined radius passing through its center along the radial center point of said hemispheres such that the flux in the cavity of the hemisphere abruptly changes when passing from the first hemisphere flux to the second.

Some microwave applications require a strong magnetic field that varies in strength along the path of a radiation-generating electron beam. For example, a gyrotron-type device requires an abrupt step-like magnetic field that varies along an electron beam path. Such gyrotron-type devices comprise a tandem of coaxial chambers made of permanent magnet structures wherein each chamber generates a uniform axial magnetic field having a predetermined magnitude and direction. Since each chamber in tandem can be configured to generate a magnetic field different from the other chamber, the magnetic field at the juncture of the two chambers may be configured to have a step profile.
Many gyrotron-type devices do not require that there be a perfect step profile as a function of distance along the axis of the bi-chambered device. It has been recognized by those skilled in the art, however, that the ability to produce a gyrotron-type device having such a perfect step profile would be a useful addition to the repertoire of field forms attainable with permanent magnets.
A first step in the attainment of such a device was disclosed in an article entitled "Magnetic-field source for bi-chambered electron-beam devices," authored by the applicants in the Journal of Applied Physics No. 67 (9), on May 1, 1990. In this article it was disclosed that the broad transition in the magnetic field values between the juncture of the two chambers can be sharpened by implementing a radially magnetized permanent magnet ring at the juncture of the chambers. The ring was placed in the interior rather than on the outside of the device to prevent unwanted polarization of the iron pole pieces at the joints as the magnetic ring produces a smaller field at its exterior.
Smoothing of the field transition can also be accomplished by the addition of axially magnetized rings whose fields are equivalent to the changes resulting from an alteration in the remanence in the supply magnet at the location in question.
Such field transition sharpening techniques are effective on these devices only when the required fields are on the order of, but no greater than, one-half the coercivity of the permanent magnet materials that comprise the structure.
Consequently, those skilled in the art recognize the need for a device that can provide a stepped internal field having a magnitude greater than that of one-half the coercivity of the permanent magnet materials that comprise the shell without adding to the overall size and cost of the device.

The United States of America as represented by the Secretary of the Army


Printer head shuttles configured to control contact pressure of one or more printer head assemblies against a printing substrate and an underlying platen during a printer operation are shown and described. The printer head shuttles include a shuttle guide and a shuttle main body having one or more printer head assemblies. Each printer head assembly includes an axel attached to the shuttle main body, an assembly main body pivotably attached to the axel, a mounting plate attached to the assembly main body, a printer head attached to the mounting plate, and a drive mechanism for pivoting the head assembly between a substrate compressing position and a substrate non-compressing position.

The present disclosure relates generally to printer head shuttle and printer head assemblies for supporting and operating a printer head. In particular, printer head shuttles and printer head assemblies configured to control contact pressure of printer head assemblies against a printing substrate are described.
Printers (e.g., thermal printers, toner-based printers, liquid inkjet printers, solid ink printers, dye-sublimation printers, etc.) are peripheral computer devices that are used to create a printed graphic or text on a printing substrate (e.g., paper, plastic sheets, etc.). In general, a printer includes a printer head for transfer of the printed graphic or text on the substrate. Position and/or operation of the printer head is controlled by a printer head assembly and a printer head shuttle, which move the printer head across the printing substrate.
Known printer head shuttles and printer head assemblies are not entirely satisfactory for the range of applications in which they are employed. In one example, existing printer head shuttles and printer head assemblies can propagate "waves" in the printing substrate as they move across the substrate surface. In other words, a small fold may form in the substrate and the printer head shuttle and/or printer head assembly may sustain and/or increase the fold across the substrate causing a blank space on the final printed surface.
In another example, conventional printer head shuttles and printer head assemblies provide uneven pressure of the printer head on the substrate, causing uneven coloration (i.e., saturation) in the printed graphic and/or text. Additionally, known printer head shuttles and printer head assemblies have high power requirements that are often subject to overheating, which can cause misprinting.
Thus, there exists a need for printer head shuttles and printer head assemblies that improve upon and advance the design of known printer head shuttles and printer head assemblies. Examples of new and useful printer head shuttle and printer head assemblies relevant to the needs existing in the field are discussed below.
Disclosure addressing one or more of the identified existing needs is provided in the detailed description below. Examples of references relevant to printer head shuttles and printer head assemblies include U.S. Patent Reference: patent publication 20020033874. The complete disclosures of the above patent application is herein incorporated by reference for all purposes.

Printer head shuttle and printer head assembly systems


An apparatus and method for testing rutting susceptibility of test specimens. The apparatus includes a specimen holder having cavities for receiving one or more test specimens having an exposed surface for testing. A load bearing surface is positioned above the specimens to prevent friction from effecting the rutting analysis. A load device including at least one loading wheel is positioned adjacent the specimen holder wherein the loading wheels matingly engage the load bearing device. A motive sources provides relative rotational movement between the specimen holder and the loading wheels whereby a load is repeatedly applied to the test specimens under a constant velocity. The method includes testing rutting susceptibility of test specimens by providing a rotational load thereupon whereby the load reflects a linear or constant load across the predetermined path of travel of the loading wheels over the exposed surface of the test specimens.

Rutting on asphaltic pavement has been a significant concern of highway commissions in the United States. Rutting is caused by a load passing repeatedly across the surface of pavement and results in lateral spreading of the pavement from the location of load application, thereby producing a rut or groove. This problem has increased in severity as the wheel loads and truck traffic on highways have increased. Rutting may cause roads and highways to become non-serviceable and dangerous. If excessive, rutting may produce hazardous conditions, such as increasing the likelihood of vehicle hydroplaning due to water accumulating in the formed rut.
Because of these problems and dangers, highway commissions in the United States and throughout strive to install the safest and most economical pavement available. Hence, test specimens of the prospective pavement material must be tested during the developmental stages, i.e., prior to construction, to determine the susceptibility of a given material to damage by rutting.
Various devices and test methods have been proposed for testing asphalt pavement. For instance, U.S. Pat. No. 3,119,257 to Speer is directed to a traffic simulator apparatus and method. The test track of that apparatus is polygonal and is formed of plural elongated, substantially rectangular paving strips joined end to end. A central column including a turntable apparatus from which radially arms extend therefrom are provided wherein each arm retains a wheel, preferably an actual rubber tire. The central column is rotated so the wheels traverse the upper surface of the polygonal track. The apparatus of Speer is extremely large, making it impractical in a laboratory environment.
The Georgia Loaded Wheel Testing Apparatus, developed by James S. Lai, Professor School of Civil and Environmental Engineering, Georgia Institute of Technology with the cooperation of the Georgia Department of Transportation, was initially developed in 1985 and modified in 1992. The Georgia Loaded Wheel Testing Apparatus is a two part system. A compactor creates a compacted hot mix asphalt specimen and a wheel tracking system repeatedly applies a load to the specimen. The wheel tracking system includes a slidable tray for retaining a beam sample tray for holding the samples. The slidable tray is associated with a reciprocating drive assembly. An inflated tube is positioned over the specimen and a weighted wheel is positioned thereover wherein the specimens are rotated to create rutting. The wheels are thus passed in a reciprocating or side to side manner, whereby the time and velocity of the load application across the specimen is sinusoidal. This type of load, however, is dissimilar to actual loads applied to pavement. Furthermore, the reciprocating motion of the specimen is an inefficient use of energy when the motion is driven by a rotating motor.
Other attempts related to asphaltic pavement testing include the Hamburg Wheel Tracking Device manufactured by Helmut-Wind, Inc. of Hamburg, Germany. The Hamburg Device is used to measure moisture sensitivity as well as rutting susceptibility. A weighted steel wheel is rolled back and forth over a compacted specimen which is immersed in water. The rate of deformation is used to determine the susceptibility to water damage, stripping, and rutting. Stripping results from the direct contact of the steel wheel against the surface of the specimen. Like the Georgia Loaded Wheel Tester, the wheels of The Hamburg Device are reciprocated across the surface of the test specimen resulting in a load wherein the time and velocity of the load application upon the specimens is sinusoidal.
These and other prior art approaches have many shortcomings or limitations which significantly restrict their usefulness or practicality as a laboratory test instrument for achieving accurate and reproducible evaluations of the susceptibility of a test specimen to rutting.

Apparatus and method for measuring rutting susceptibility


A system and method for efficiently and economically providing a sufficient number of air changes per hour to satisfy government recommended standards for proper ventilation of industrial manufacturing facilities. The system is applicable to a building, housing manufacturing facilities and forms an enclosure within the building including the ceiling, floor and certain walls. The ventilation system may include an air-impervious curtain attached to the ceiling and to one or more walls, with a lower edge spaced above the floor to form the enclosure; and includes further an air supply assembly including ceiling mounted fans, vertical and horizontal ductwork for forcing outside unconditioned air into the enclosure at appropriate air flow rates and through a discharge slot formed in the horizontal ductwork at a level spaced above the floor, generally equal the height of the curtain lower edge above the floor; air heating units mounted within the building for forcing heated air from exterior the building into the enclosure; a plurality of ceiling mounted fans for withdrawing air trapped within the enclosure and exhausting it into the atmosphere; and a control unit for controlling the air supply assembly, the air heating units and the air exhaust fans for effecting a predetermined number of air changes within the enclosure.

The prior art is replete with ventilating systems designed for operation in an effective, efficient manner to condition the air within a given building structure. The problem is exacerbated when the air to be conditioned exists within buildings of varying size and wherein industrial machinery is used. Industries, such as foundries, for example, and fabrication or welding plants use machinery which produces contaminated air which may pose a health hazard to the workers within the industrial areas.
Although various methods and systems have been devised for cleaning industrial air, such as filters, dust collectors, electrical precipitators, water wash and the like, there is still a need in the industry for an effective, efficient system to meet contemporary government O.S.H.A. PEL (Permissible Exposure Levels) requirements.
The problem is further compounded by the present cost of heat. Certain present day systems appear to achieve the PEL requirements, however, require abnormally high energy, (heating) costs, particularly for the make-up air, thus rendering those systems cost ineffective. It is to the provision of a method and system of cleaning air within a given industrial area to comply with industry standards and to achieve a marked energy saving that the present invention is directed.

Method and system of cleaning industrial air

Brockway Mechanical and Roofing Company, Inc.


A method of device initialization in a network is provided. An explicitly routed management cell is received at a device. The management cell includes initialization information, such as an address or a forwarding database. The management cell also includes information specifying an explicit route for the cell to traverse to reach the device. The device is initialized based on the initialization information in the received management cell. One or more subsequent cells are routed through the device using the more efficient destination address routing technique after the device is initialized.

The invention generally relates to data networks and in particular to a technique for initializing or configuring devices or switches in a network.
In computer networks, data cells are generally routed using one of two methods. The first method involves the insertion of a xe2x80x9cdestination addressxe2x80x9d in the cell. Each switch or device within the network contains a forwarding database (also known as a routing table). This forwarding database contains an entry for each known destination address along with information related to how the cell is to be routed. The forwarding database usually lists an output port corresponding to each known destination address. This method requires that the forwarding database be configured before cells can transit the network. This configuration may be accomplished by a central configuration device or by various algorithms that permit each of the devices, with the cooperation of adjoining devices, to learn routes throughout the network.
The second method is explicit routing. In this method, the entire route that a cell is to transverse is explicitly stated within the cell. Each switch or device forwards the cell based on the information within the cell. Consequently, the devices within the network are not required to maintain forwarding databases.
A major limitation of destination address routing is the requirement of each device within the network to contain a configured forwarding database before data communication can take place. To achieve this, complex algorithms are required that allow each device to learn the topology of the network and to make appropriate forwarding database entries. Alternatively, a central device can configure the network; however, this is complicated by the fact that methods must be provided for the central device to learn the topology of the network without the network functioning. A second limitation is additional network complexity (redundancy) to provide network fault tolerance. Many networks are configured with multiple paths between points on the network. In this way, if a link fails, cells maybe routed along alternate paths maintaining communication in the presence of the fault. With destination address routing, complex algorithms must be provided to detect such faults, and to determine alternate routes around the faults. The time required to perform these functions, referred to as network convergence time, may be unacceptably long for certain applications.
Explicit routing eliminates the need to configure devices within a network to enable communication. However, explicit routing requires significantly increased processing by the communicating devices. This is due to the fact that an originating device must maintain information regarding the entire route between itself and the final destination. Furthermore, network efficiency is reduced since the entire route must be carried within the cell. And finally, network performance may be reduced since the intervening devices must examine more data within the cell before a forwarding decision can be made.
Therefore, a need exists for a more flexible technique for routing cells through a network which provides the advantages of both the destination address routing and explicit routing techniques.

Device initialization and operation using directed routing


A navigation method and system determines a more accurate position of a street address number with use of building footprint information or latitude/longitude information of POI (point of interest), thereby accurately defining a position of a destination. When a user specifies a street address number as his destination, the navigation system retrieves the street segment that should include the location of the specified address number therein. The navigation system also checks the map data as to whether there is any building footprint data or POI position data associated with the street segment. The navigation system selects absolute locations on the street segment based on the building footprint data or the POI position data and determines the location of the specified address number by interpolating between two absolute locations.

A navigation system performs travel guidance for enabling a user to easily and quickly reach the selected destination. A typical example is a vehicle navigation system where a vehicle carries a navigation function. Such a navigation system detects the position of the user or user's vehicle, and reads out map data pertaining to an area at the current vehicle position from a data storage medium in the navigation system. The navigation system displays a map image on a monitor screen while superimposing a mark representing the current location of the user on the map image. When a destination is set, the navigation system starts a route guidance function for setting a guided route from the start point to the destination and guides the user to the destination.
FIGS. 1A-1H show an example of overall procedure and screen display involved in the navigation system. FIG. 1A shows an example of locator map screen of the navigation system typically used when the destination is not specified. The navigation system displays a street on which the vehicle (current vehicle position VP) is running on a map image and a name of the street. Other information such as a north pointer NP, a map scale and a current time may also be illustrated on the display screen.
FIGS. 1B-1F show an example of process for specifying a destination in the navigation system. When selecting a "Destination" menu on a main menu screen of FIG. 1B, the navigation system displays an "Find Destination By" screen as shown in FIG. 1C for specifying an input method for selecting the destination. The "Find Destination By" screen lists various methods for selecting the destination. This example includes the methods of "Address", "Intersection", "Point of Interest", "Recent Route", "Address Book", and "Today's Plan" which are well known in the art.
When selecting, for example, the "Address" method in FIG. 1C, the navigation system displays a keyboard screen in FIG. 1D. Suppose the user inputs an address "2525 W. Carson" of a "Del Amo" shopping mall, the navigation system displays a "Confirm Destination" screen such as shown in FIG. 1E. If the name and address on the screen shows the correct destination, the user enters an "OK to Proceed" key to proceed to the next procedure.
In FIG. 1F, the navigation system calculates and determines a route to the destination, i.e., the address "2525 W. Carson". The navigation system determines a route to the destination based on, for example, the quickest way to reach the destination, the route using many free ways as possible or the route without using toll road, and the like. In this example, the navigation system displays a progress scale of the calculation of the route.
Once the route to the destination is determined, the navigation system starts the route guidance as shown in FIG. 1G for guiding the user to the destination. Typically, the navigation system shows the intersection which is highlighted to show the next turn and a direction of the turn. Such route guidance by the navigation system is also accompanied by voice instructions. By approaching every intersection to turn, the navigation system automatically displays the intersection guidance diagram to instruct the user which direction to turn at the intersection.
The navigation system measures a distance to the current destination to detect whether the destination is within a predetermined range such as within 100 meters. When the user approaches the destination within such a predetermined distance, the navigation system indicates that the destination "Dest" is ahead as shown in FIG. 1H. The navigation system detects the actual arrival based on various factors such as the engine stop.
In the foregoing process, the point which the navigation system indicates as the destination may not exactly be an actual position of the destination intended by the user. For example, in the conventional navigation system, the position of the destination calculated by the system sometimes does not match the actual position of the street address. This is because the map information usually shows only the address number and absolute position of each end of a street segment. Thus, the map data does not always include an accurate position of street address for each and every address number on the street.
Such a situation is shown in FIGS. 2A-2C. FIG. 2A shows the address distribution on a street segment of a particular street "2525 Carson W. Street" in FIGS. 1A-1H which is assumed by the navigation system. FIG. 2B shows an example of actual address distribution on the street segment of FIG. 2A. For example, as shown in FIG. 2A, the map data provides the street address number and its position of each end of a street segment. Thus, although the address number and position at each end (1000 and 4000) of the street segment are accurate, positions of intermediate addresses are not always accurate. This is because they are spread evenly by the navigation system, i.e., with a constant interval, along the street between the lowest address number and the highest number of the street segment. Thus, the address number "2525 Carson W. Street" in FIGS. 1A-1H is assumed to be at the location shown in FIG. 2A.
However, since the actual address numbers are assigned irregularly as shown in FIG. 2B, the actual position (arrival position) of the destination is different from the position of FIG. 2A by a distance d. Therefore, a user may be confused when the navigation system announces the arrival at the incorrect position on the street. FIG. 2C shows another example of actual address distribution where address numbers on the street in a residential area is proportionally assigned with relatively small interval while the address numbers on the street in a park, field or vacant land are assigned unevenly, i.e., by an irregular interval with relatively large interval.
Therefore, there is a need of a new navigation method system which is able to improve the performance in interpreting an address number of a destination based on the other information contained in the map database so that the actual position of the destination can be determined more accurately.

Navigation method and system for accurately estimating positions of street address numbers


A fabrication method of a semiconductor stack structure mainly includes: singulating a wafer of a first specification into a plurality of chips; rearranging the chips into a second specification of a wafer so as to stack the chips on a substrate of the second specification through a plurality of blocks; forming a redistribution layer on the chips; and performing a cutting process to obtain a plurality of semiconductor stack structures. Therefore, the present invention allows a wafer of a new specification to be processed by using conventional equipment without the need of new factory buildings or equipment. As such, chip packages can be timely supplied to meet the replacement speed of electronic products.

1. Field of the Invention
The present invention relates to semiconductor stack structures and fabrication methods thereof, and more particularly, to a semiconductor stack structure having a plurality of wafers of different specifications and a fabrication method thereof.
2. Description of Related Art
Along with the rapid development of electronic industries, planar packaging technologies have reached their limits and hence integrating technologies are developed to meet the miniaturization requirement of electronic products. For the purpose of multi-function, a plurality of homogeneous or heterogeneous wafers are stacked.
However, a set of process equipment in a wafer packaging factory is specially used for processing a certain specification of wafers. To process a different specification of wafers, a different set of process equipment is required. For example, 8-inch equipment is used for processing 8-inch wafers and 12-inch equipment is used for processing 12-inch wafers. As such, newly developed electronic products need new equipment and even new factory buildings for processing, which adversely affects timely supply of chip packages and cannot meet the replacement speed of electronic products.
Therefore, there is a need to provide a semiconductor stack structure and a fabrication method thereof so as to overcome the above-described drawbacks.

Semiconductor stack structure and fabrication method thereof


There is provided a surface treated product that moves relatively in a fluid, wherein a surface of the surface treated product has continuous dimples, each dimple having a diameter of 10 to 2500 μm and a depth of 50 μm or less. The surface treated product significantly reduces resistance of a fluid to an object in the fluid, and significantly improves a flow state of the fluid.

The present invention relates to a surface treated product that moves relatively in a fluid.
A technique of improving a flow state of a fluid is known such as providing dimples on a surface of an object on which a fluid flows to reduce resistance of the fluid. It is well known that a golf ball with dimples provides a long carry, and such a technique is disclosed in several patent documents.
For example, Japanese Patent Laid-Open No. 11-304300 (Patent document 1) proposes an efficient and noiseless refrigeration cycle in which a plurality of dimples are formed on a surface of a part through which a coolant passes. Japanese Patent Laid-Open No. 8-247343 (Patent document 2) discloses a heat exchanger tube in which many dimples are provided on an inner peripheral surface to improve heat transfer efficiency. Japanese Patent Laid-Open No. 10-28314 (Patent document 3) discloses a pipe type jumper apparatus in which dimples are formed on a surface to reduce air resistance and reduce rolling caused by wind pressure loads. Further, Japanese Patent Laid-Open No. 11-190471 (Patent document 6) proposes a pipe with low pipe line resistance in which pipe line resistance is reduced for use as a horizontal pipe line, and Japanese Patent Laid-Open No. 2000-55014 (Patent document 7) proposes a fluid resistance reducing apparatus in which dimples are arranged orderly to significantly reduce fluid resistance.
The applicant of the present invention proposes an intake pipe for an engine in which a wall surface of an intake passage is uneven with many small protrusions and recesses in Japanese Patent Laid-Open No. 5-149204 (Patent document 4), and proposes an exhaust pipe for an engine in which a wall surface of an exhaust passage is uneven with many small protrusions and recesses in Japanese Patent Laid-Open No. 5-149132 (Patent document 5), and achieves certain advantages.

Surface-treated product, surface-treatment method, and surface-treatment apparatus


An isolator for supporting an exhaust component from a portion of a vehicle via a hanger includes elastomeric isolator element having at least one aperture adapted to receive the hanger and an isolator or bracket for receiving and supporting the elastomeric isolator element. The isolator bracket includes a mounting structure including a first aperture and a second aperture. The isolator bracket is adapted to be fixed to the vehicle by a single fastener extending through the first aperture. The second aperture extends through the isolator bracket and includes an internal wall shaped as a polygon. A target orientation of the isolator bracket relative to the vehicle is obtained when the internal wall of the second aperture is angularly oriented and coaxially aligned with a corresponding aperture in the portion of the vehicle having an internal surface with the same polygon shape as the second aperture.

Automotive vehicles may be equipped with an internal combustion engine for providing motive power to driven wheels of the vehicle. An engine exhaust system may include one or more exhaust pipes, catalytic converters, mufflers, and tailpipes in receipt of exhaust gas emitted from the internal combustion engine. The engine exhaust system functions to minimize the noise and release of undesirable constituents of the exhaust gas to the atmosphere.
The exhaust system may be supported by exhaust mounts or isolators that interconnect the exhaust system and the vehicle. More particularly, the isolators are often times mounted to a body or a frame of the vehicle in order to prevent engine movement and or vibrations from being transmitted to the components of the exhaust system or vice versa. The isolators may incorporate flexible mounting members or elastomeric internal components to isolate the vehicle's body from the exhaust system.
In present-day vehicles, many components are positioned under the vehicle body and packaging space for the exhaust system as well as the isolators is limited. Access to fasteners used to attach the isolators to the vehicle may also be limited. Many exhaust isolators are configured to cooperate with a hanger that is attached to the vehicle's frame or some other support structure of the vehicle's body. Alternatively, the hanger may be fixed to one of the components of the exhaust system such as a muffler or an exhaust pipe.
The hanger may be shaped as a cylindrical rod and the isolator may include an aperture in receipt of the rod. To provide the desired vibration isolation function, it may be important to maintain alignment between a centerline of the rod and a geometrical feature of the isolator. Based on the limited packaging space and limited access to fasteners coupling the isolator to the vehicle, it may be challenging for an installer of the isolator to the vehicle to maintain a desired relative position of the isolator to the hanger and/or the vehicle body. Accordingly, it may be desirable to provide an improved isolator having an alignment feature used during the installation process.

Exhaust isolator bracket with alignment feature


A radiation polarizer, controller, and a method of radiation polarization and beam control, are disclosed. The radiation polarizer includes a substrate, at least one anti-reflection coating layer communicatively coupled to the substrate, at least two nanostructures communicatively coupled to the at least one anti-reflection coating layer, and at least two groove layers, wherein each one of the at least two groove layers is interstitial to a respective one of the at least two nanostructures. The method may include the steps of communicatively coupling at least one anti-reflection coating layer to a substrate, communicatively coupling at least two nanostructures to at least one of the at least one anti-reflection coating layer, providing interstitially to a respective one of the at least two nanostructures at least two groove layers, coupling the at least two groove layers and the at least two nanostructures to provide a pass wavelength in the range of about 250 nm to less than about a microwave wavelength, and allowing for examining of radiation having a wavelength in a range of about 250 nm to less than about a microwave wavelength, and having an electric field orthogonal to the at least two groove layers, by allowing for a passing of the radiation through said coupling of the at least two groove layers and the at least two nanostructures.

A light wave may be formed of electrical field vectors, i.e. peaks and troughs, radiating out in all directions from the direction of propagation of the light wave. A polarizer may be, in essence, a screen that allows only a narrow segment of the vectors to pass, namely those vectors that are oriented in a specific plane.
A polarizer may be used for beam splitting, combining, polarization, or like-functions, and may be formed of a series of extraordinarily thin conductive "ribbons", each running parallel to each other of the "ribbons". This is known as a wire-grid, or grating, polarizer. In an instance wherein radiation, such as visible or infrared light, strikes the wire-grid of the polarizer, some of that radiation is reflected, while that portion of the radiation that is selectively polarized by the wire grid may pass. Such a wire grid polarizer polarizes the radiation wave incident on the parallel conductors perpendicularly to the length of the conductors.
The grid, or grating, of a grid polarizer may be highly dense, due, in part, to the fact that the "ribbons" must be closer together than the wavelength of the radiation to be polarized, controlled, or analyzed. Thus, the smaller the wavelength of the radiation to be operated on is, the more dense the wire grid must be in order to operate on the subject radiation. This has been, as is known in the art, a limitation on the types of radiation that may be polarized using such a polarizer. For example, wire grid polarizers/beam splitters have historically been used in the microwave region, in which longer wavelengths make the construction more feasible.
The polarization of radiation may be used to control the radiation that is the subject of the polarization, such as in a splitter or combiner, and to analyze the polarization characteristics of an object, such as by examining the light reflected from, or by, an object. Polarization characteristics may provide for extraction of significant information about the physical and chemical makeup of an object and of a surface. A polarizing beam splitter may thus act as an analyzer, for example, reflecting unwanted light, and passing desired light.
Exemplary optical and electro-optical polarizer applications may include lasers, glare-reduction, lens coating, display enhancement, and exploitation of limited bandwidth availability, to name a few. For example, through "frequency reuse," an antenna may simultaneously transmit adjacent beams at the same frequency, and, by polarizing each beam differently, nonetheless maintain useful beam isolation.
In the fields of optics, telecommunications, optical and electro-optical applications and photonics, it may be highly desirable to enhance device performance and reduce fabrication, packaging and assembly costs, such as by providing polarization capabilities that provide improved performance through a broader range of radiation, but that can be fabricated at low cost. For example, it may be desirable to provide a improved photonic component, which may be incorporated into a Photonic Integrated Circuit (PIC), or with another photonic device.
Accordingly, it is desirable to provide a polarization controller, system, device, and method that employs nanostructures to perform polarization, thereby providing improved performance through a broader range of radiation wavelengths at a low fabrication cost.

Method and system for providing beam polarization


The present invention provides an apparatus for generating L-band light source and an optical signal amplifier, specifically, relates to an apparatus for generating L-band light source by increasing amplification gain against an L-band light to execute a stable resonating operation, and to an optical amplifier which amplifies L-band light signal efficiently. That is, it is possible to use the output light of the first optical fiber amplifier 10 as a pumping light of the second optical fiber amplifier 20 by connecting the first optical fiber amplifier 10 for supplying a maximum amplification gain against an input light having a wavelength of 1530 nm to 1560 nm with the second optical fiber amplifier 20 for supplying a maximum amplification gain against an input light having a wavelength of 1570 nm to 1610 nm in series, thus securing a satisfied amplification gain against a L-band light and to generate a desirable light source.

1. Field of the Invention
The present invention relates to an apparatus for generating L-band light source and an optical signal amplifier, specifically, relates to an apparatus for generating L-band light source by increasing amplification gain against an L-band light to execute a stable resonating operation, and to an optical amplifier which amplifies L-band light signal efficiently.
2. Discussion of Related Art
In general, an optical transmission apparatus uses a wavelength band of approximately 1530 nm to 1560 nm, such as commercial band C-band or middle band M-band, which is caused by characteristics of optical amplifier for amplifying optical signal transmitted mostly through optical line. At present, the optical amplifier is configured in a manner that a pumping light of 980 nm or 1480 nm is supplied with an erbium-doped-fiber EDF doped with a rare earth ion such as erbium. As shown in FIG. 1, a graph showing amplification gain characteristics of the optical fiber amplifier, the optical fiber amplifier provides an efficient amplification gain in a wavelength band of approximately 1530 nm to 1560 nm. Meanwhile, the optical transmission system using C-band needs an apparatus for generating a light source having corresponding wavelength band. In general, the light source generating apparatus uses a semi-conductor laser device or the erbium-doped-fiber EDF. The light source generating apparatus using ELF has a ring-type structure generally which returns amplified signal output from the EDF back to the EDF through a specific tunable filter.
FIG. 2 is a block diagram of a conventional light source generating apparatus having the ring-type structure. Reference numeral 1 denotes a pumping laser diode which outputs pumping light of 980 nm or 1480 nm, for example. Pumping light output from the pumping laser diode 1 is input to an erbium-doped-fiber EDF 3 through a wavelength division multiplexer WDM 2. Then, optical signal output from the EDF 3 is input to a tunable filter 5 through an isolator 4 which passes a specific wavelength light. The specific wavelength light output from the tunable filter 5 is returned back to the EDF 3 by way of a tap coupler 6, an isolator 7 and the wavelength division multiplexer WDM 2. The tap coupler 6 divides optical signal output from the tunable filter 5 in a predetermined ratio, for example 70:30, and outputs the 70% light as an output light and the 30% light to the isolator 7 as an input. In the above configuration, it is possible to form a resonating structure for a specific wavelength light by returning the amplified light output from the EDF 3 back to the EDF 3 through the tunable filter 5, and to obtain the specific wavelength light by outputting the amplified light through the tap coupler 6.
Meanwhile, as optical communication techniques have been developed rapidly, a wavelength division multiplexing WDM transmission technique for transmitting optical signal having plural wavelengths through one optical line simultaneously has been widely used so as to increase transmission efficiency of the optical line. Accordingly, the wavelength division multiplexing WDM system requires methods for transmitting a large number of wavelengths, i.e., channels through a single optical line at a time. However, as described above, it is very difficult to secure a large number of channels more than a predetermined number since the available wavelength band in the present optical transmission system is confined within 1530 nm to 1560 nm due to the amplification characteristics of the optical fiber amplifier. In consideration of the above obstacle, an advanced methods has been studied for transmitting optical signal using a L-band, i.e., a wavelength of 1570 nm to 1610 nm, no the C-band. By this means, it is considered to increase the amplification efficiency of L-band light by altering the length of the EDF 3. That is, the L-band gain of the EDF 3 is increased according as the EDF 3 is lengthened. For example, if the length of the EDF 3 is 21 m, the gain is increased against the wavelength of 1530 nm to 1560 nm, if the length is 100 m, the gain is increased against the wavelength of 1570 nm to 1610 nm. However, since it is also impossible to obtain more than a maximum xe2x88x9250 dB output power by supplying a normal pumping light even though the EDF 3 is lengthened to increase the amplification gain of L-band light, it is readily appreciated that the above method is inadequate to amplify the L-band light. Besides, in the light source generating apparatus having the ring-type structure as shown in FIG. 2, a light having a wavelength more than 1600 nm is not resonated and the gain is decreased since the amplification gain of L-band is very weak as shown in FIG. 1. Consequently, it is impossible to generating L-band light by using the EDF 3.
Accordingly, the present invention is directed to an apparatus for generating L-band light source using optical fiber, and an optical amplifier that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an apparatus for generating L-band light source using optical fiber amplification.
Another object of the present invention is to provide an optical amplifier which can amplify L-band light efficiently using optical fiber amplifiers.
Another object of the present invention is to provide an apparatus for generating L-band light source and an optical amplifier which has a single structure so as to be alternatively used as the apparatus for generating L-band light source or the optical amplifier.
To accomplish an object in accordance with a first embodiment of the present invention, there is provided an apparatus for generating L-band light source using optical fiber comprising, in accordance with a first embodiment of the invention comprising: a first optical fiber amplifier for supplying a maximum amplification gain against an input light having a wavelength of 1530 nm to 1560 nm; a second optical fiber amplifier, connected with the first optical fiber amplifier, for providing a maximum amplification gain against an input light having a wavelength of 1570 nm to 1610 nm; and a tunable filter for passing an input light having a specific wavelength from the light output from the second optical fiber amplifier, the output light of the tunable filter is input to the first optical fiber amplifier, a tap coupler is established on an optical line through which the output light of the second optical fiber amplifier is forwarded to the first optical fiber amplifier.
To accomplish an object in accordance with a second embodiment of the present invention, there is provided an optical amplifier comprising: a first optical fiber amplifier, connected with an optical line in series, for supplying a maximum amplification gain against an input light having a wavelength of 1530 nm to 1560 nm; and a second optical fiber amplifier, connected with the first optical amplifier, for providing a maximum amplification gain again an input light having a wavelength of 1570 nm to 1610 nm.
To accomplish an object in accordance with a third embodiment of the present invention, there is provided an apparatus for generating L-band light source and an optical amplifier comprising: a first optical fiber amplifier for supplying a maximum amplification gain against an input light having a wavelength of 1530 nm to 1560 nm; a second optical fiber amplifier, connected with the first optical fiber amplifier, for providing a maximum amplification gain against an optical signal having a wavelength of 1570 nm to 1610 nm; a tunable filter for passing an input light having a specific wavelength from the light output from the second optical amplifier; a switching means for inputting the output light of the tunable filter or a specific input light selectively to the first optical fiber amplifier; and a tap coupler for receiving the output light of the second optical fiber amplifier and outputting a predetermined amount of light as an output light.
According to the above configuration of the present invention, the first optical fiber amplifier supplying a maximum amplification gain against an input light of a wavelength of 1530 nm to 1560 nm and the second optical fiber amplifier providing a maximum amplification gain against an optical signal of a wavelength of 1570 nm to 1610 nm are connected with each other in series so as to use the output light of the first optical fiber amplifier as a pumping light of the second optical fiber amplifier. Accordingly, it is possible to supply a satisfied amplification gain and a stable resonating operation against a L-band signal light, thus generating a good light source.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Apparatus for generating L-band light source using optical fiber, and optical amplifier