A multifunction electrode (MFE) pad, which includes a multi-strand conductor having one end in the form of dispersed carbon fibers, and another end adapted for connection to a defibrillation unit. A conductive substrate is in electrical communication with one end of the multi-strand conductor. The conductive substrate includes a conductive back side, an intermediate conductive polymer layer, and a conductive front side, the front side being a metal/metal chloride coating containing at least 25% by weight of metal chloride. The MFE pad further includes a conductive hydrogel layer covering said front side of the conductive substrate and a backing layer covering one end of the multi-strand conductor and the back side of the conductive substrate. The backing layer has a surface area that is greater than the surface area of the conductive hydrogel layer.

Multifunction Electrode (MFE) pads are widely used in the treatment and diagnosis of cardiac ailments. Health care professionals and other first-aid providers use MFE pads to monitor the electrical potential during a heartbeat, to provide high-energy electrical stimulation for defibrillation, and to provide lower level electrical stimulation for pacing. Prior to the development of such pads, care providers were required to apply multiple types of pads and possibly use other means of transferring electric current to the patient (i.e., paddles). As one can easily imagine, the use of multiple electrodes along with the use of other devices leads to potential errors and further injury when implemented during an emergency situation.
The creation of a true MFE pad requires designers to balance many factors, not the least of which is price, since the pads are single-use only. A modern MFE pad must be able to transfer short bursts of significant electrical energy while being able to dissipate such energy quickly so that monitoring remains unaffected. MFE pads must also evenly distribute energy across the surface of the pad to reduce the likelihood of burning a patient wearing the pad. Additionally, MFE pads must remain transparent to x-ray transmissions to allow for diagnostic imaging without removal of the pads.
MFE pads contain at least three layers used to effect the transfer of electrical energy between an electrical device and the patient. An electrode layer is located between a layer of protective outer foam and a layer of conductive gel. The conductive gel ensures contact between the electrode layer and the patient's body. The layer of foam, sized to be larger than the electrode layer, is added to cover the electrode and gel layers. The added size allows the foam to extend beyond the periphery of the other two layers to insulate and protect the electrode and gel layers while adding additional adhesive capacity around the periphery of the pad.
The conductive gel spans the distance between the electrode layer and the patient's body. The gel functions to wet the patient's skin making it more accepting to the flow of electrical energy. The physical properties of the gel also help to ensure contact over the entire surface of the exposed gel to distribute the energy being transferred. Lastly, the gel functions as an adhesive helping to ensure that distributed contact with the patient is maintained.
The electrode layer often includes a metal/metal chloride film adhered to a carbon-filled polymer sheet, which is typically a carbon-filled polyvinyl chloride (PVC). The sheet helps to support the metal/metal chloride film. The metal is the primary conductor of the electric energy across the pad while the chloride of the metal allows for the conduction of electrical energy from the electrode to the gel.
The ability of an MFE pad to dissipate energy quickly has come under significant scrutiny. The American National Standards Institute (ANSI) along with the Association for the Advancement of Medical Instrumentation (AAMI) publishes standards for the testing and performance of MFE pads. In particular, a standard known as ANSI/AAMI DF2:1996 was developed to standardize the performance testing of MFE pads and to provide target or allowable limits for the accumulation of DC offset potential measured across a pair of MFE pads.
A measure of an MFE pad's DC offset potential is a measure of the pad's ability to provide energy transfer while retaining the capability to monitor. Electrode pairs store energy by effectively forming a capacitor with the metal layer forming one plate of the capacitor, the human body forming another plate of the capacitor, and the hydrogel forming the dielectric material between the plates. This energy buildup can be seen as a residual voltage between periods of electric energy transfer from the electrode to the patient. This residual voltage or "DC offset potential" has a negative effect of skewing or masking electric signals being generated by the patient's nervous system being monitored through the electrode. Therefore, the lower the DC offset potential the better.
ANSI/AAMI DF2:1996 requires that the DC offset potential across a pair of MFE pads remain less than 400 mV during 60 minutes of pacing, where pacing includes 170, 20 millisecond pulses of 200 mA every minute. While most of the pads currently available continue to fail this standard, one pad, a Philips M3718A, appears to meet these requirements. The construction of this MFE pad is disclosed in U.S. Pat. No. 6,600,957, the entirety of which is incorporated herein by reference.
Current knowledge in the art indicates that the only way to meet the requirements of ANSI/AAMI DF2:1996 is to make the layer extremely thick when compared to others in the prior art. For example, U.S. Pat. No. 6,600,957, discloses that the metal/metal chloride coating of a successful MFE pad design must be "considerably thicker by a factor of six in order to enable the electrode to meet certain pacing requirements which the prior devices are unable to meet." This metal/metal chloride film of the electrode layer is very expensive to create and apply. Therefore, MFE pads containing such thick layers are very costly, especially for a disposable item.
The current financial crisis affecting the medical care systems around the world can hardly afford the use of expensive MFE pads incorporating a larger amount of expensive components, especially in a disposable product. However, heath care providers should be able to purchase MFE pads that meet the standards currently outlined in ANSI/AAMI DF2:1996 for the safety it offers to the people in need of safe cardiac treatment and care. To date, no such low-cost MFE pad is available.


A tracking apparatus which can ensure good-accuracy coincidence between a conveyed material and a tracked position thereof, even when slip occurs in the conveyed material moving across conveyance tables. A sensor is located at a boundary position of a conveyance table, of conveyance tables arranged adjacent to each other, to detect the presence or absence of a conveyed material. Head and tail end tracking data of the conveyed material is generated, and positions of head and tail ends are calculated using conveyance speed of a selected conveyance table as a speed standard. Then, occurrence or nonoccurrence of slip of the conveyed material is determined from the detection signal of the sensor and the positions of head and tail ends. When slip has occurred, head and tail end tracking data generation is stopped. Head and tail end tracking data generation is restarted considering a time delay due to removal of chattering from the detection signal.

In conventional tracking apparatus used in material conveyance and the like of rolling equipment, tracking was caused to be generated in head and tail end positions of a conveyed material, the moving distance of the conveyed material was calculated on the basis of roll rotation (conveyance table speed) signals of a conveyance table, and the head and tail end positions were tracked (refer to Patent Document 1, for example). In the tracking apparatus described in Patent Document 1, tracking corrections were performed by calculating the amount of a slip between the conveyance table and the conveyed material on the basis of the acceleration and deceleration rate of the conveyance table.
Patent Document 1: Japanese Patent Laid-Open No. 2005-15188

Toshiba Mitsubishi-Electric Industrial Systems Corporation


There are provided an optical transfer characteristic measuring method and apparatus capable of measuring an optical transfer characteristic of an optical device on optical frequency axis in wide optical frequency bandwidth with high resolution. There are provided a variable wavelength sweep type light source capable of switching the wavelength of an optical signal generated therefrom stepwise and sweeping the optical frequency of the optical signal in a predetermined frequency range, and a variable wavelength reference light source capable of switching the wavelength of an optical signal generated therefrom stepwise and not capable of sweeping the optical frequency of the optical signal. Optical signals having their wavelengths sequentially switched to corresponding specified wavelengths are generated from the variable wavelength sweep type light source, and also a sweep of the optical frequency of each optical signal having the corresponding specified wavelength is carried out over the predetermined frequency range, until the number of occurrences of the optical signals reaches a preset number of times. After the measurement of the optical transfer characteristic has been completed, the measured results of the optical transfer characteristic regarding all of the specified wavelengths are concatenated on optical frequency axis, and is analyzed/displayed.

1. Field of the Invention
The present invention relates to a method and an apparatus for measuring an optical transfer characteristic, each of which is capable of measuring an optical transfer characteristic of an optical device in a wide optical frequency bandwidth with high resolution, on optical frequency axis or on optical wavelength axis.
2. Description of the Related Art
In case of measuring an optical transfer characteristic (characteristic of amplitude, dispersion, delay, phase, gain or the like) of an optical device such as an optical filter, an optical fiber, an optical transmission system or the like, there is currently used an apparatus for measuring an optical transfer characteristic (an optical transfer characteristic measuring apparatus) having been constructed, for example, as shown in FIG. 4. The optical transfer characteristic measuring apparatus includes two light sources one of which is a variable wavelength sweep type light source 10 for measurement (hereinafter referred to as variable wavelength sweep type measurement light source or measurement light source), and the other of which is a variable wavelength light source 20 for reference (hereinafter referred to as variable wavelength reference light source or reference light source). In the variable wavelength sweep type measurement light source 10, the wavelength of an optical or light signal generated thereby can be switched stepwise and also the optical frequency of the optical signal can be swept in a predetermined frequency range. In the variable wavelength reference light source 20, the wavelength of an optical or light signal generated thereby can be switched stepwise, but the optical frequency of the optical signal cannot be swept.
An output end of the variable wavelength sweep type measurement light source 10 is optically coupled to an input end of an optical device whose optical transfer characteristic is to be measured (optical device under measurement) DUT via a first optical coupler 30. In the illustrated example, the first optical coupler 30 has four ports, i.e., the first through the fourth ports 301, 302, 303 and 304. The first and the second ports 301 and 302 are used as input ports, respectively, and the third and the fourth ports 303 and 304 are used as output ports, respectively. The first port (the first input port) 301 is terminated in reflectionless termination, the second port (the second input port) 302 is coupled to the output end of the variable wavelength sweep type measurement light source 10 via an optical fiber, the third port (the first output port) 303 is coupled to an input end of the optical device under test DUT via an optical fiber, and the fourth port (the second output port) 304 is coupled to the second port of a second optical coupler 31 which will be discussed later. As a result, an optical signal generated from the measurement light source 10 is optically branched into two, one of which is supplied to the input end of the optical device under measurement DUT and the other of which is supplied to the second port of the second optical coupler 31.
The output end of the variable wavelength reference light source 20 is coupled to the second optical coupler 31 via an optical fiber. The second optical coupler 31 also has four ports, i.e., the first through the fourth ports 311, 312, 313 and 314. The first and the second ports 311 and 312 are used as input ports, respectively, and the third and the fourth ports 313 and 314 are used as output ports, respectively. The first port (the first input port) 311 is coupled to the output end of the variable wavelength reference light source 20 via an optical fiber, the second port (the second input port) 312 is coupled to the second output port 304 of the first optical coupler 30 as mentioned above, the third port (the first output port) 313 is terminated in reflectionless termination, and the fourth port (the second output port) 314 is coupled to an input end of a light receiving device 21 via an optical fiber. As a result, an optical signal generated from the reference light source 20 is inputted to the second optical coupler 31 via its first input port 311, and also an optical signal generated from the measurement light source 10 is inputted to the second optical coupler 31 via its second input port 312, so that the two light signals can be optically heterodyned.
Since the illustrated optical transfer characteristic measuring apparatus monitors the amount of frequency sweep (a frequency being swept) using an optical heterodyne detection, the optical signals generated from the variable wavelength sweep type measurement light source 10 and the variable wavelength reference light source 20 are first set to signals having the same frequency (the same reference wavelength), and then the frequency of the optical signal generated from the measurement light source 10 is swept within a predetermined frequency range so that both the optical signals are optically heterodyned in the second optical coupler 31. After that, an electrical signal having a frequency difference between both the optical signals, i.e., an electrical signal having an optical beat frequency is detected by the light receiving device 21 coupled to the second output port 314 of the second optical coupler 31.
As the light receiving device 21 is used, in this example, a photodetector for converting light into an electrical signal such as a photodiode, and the electrical signal having the optical beat frequency detected by the light receiving device 21 is supplied to a high frequency counter 50 after it has been amplified by an amplifier 22. Further, the light receiving device 21 and the amplifier 22 constitute a wide-band or broad-band optical receiver 29.
The high frequency counter 50 measures, based on the electrical signal having the optical beat frequency supplied from the wide-band optical receiver 29, the amount of sweep of the frequency of the optical signal generated from the variable wavelength sweep type measurement light source 10, and supplies the measured result to a measurement/analysis/display part 90. On the other hand, an optical or light signal for measurement (hereinafter referred to as optical measurement signal) inputted to the optical device under measurement DUT via the first optical coupler 30 is transmitted through the optical device under measurement DUT into the measurement/analysis/display part 90. The measurement/analysis/display part 90 carries out a measurement/analysis of the inputted optical signal, and displays the results of the measurement/analysis, if necessary. In addition, the measurement/analysis/display part 90 supplies a control signal to a variable wavelength light source control part 80, as the case may be.
Control terminals of the measurement light source 10 and the reference light source 20 are connected to output terminals of the variable wavelength light source control part 80, respectively, and the reference wavelengths of both the optical signals generated respectively from these light sources 10 and 20 are determined on the basis of wavelength setting signals supplied from the variable wavelength light source control part 80 to the control terminals of both the light sources, respectively. In addition, the variable wavelength light source control part 80 supplies a frequency sweep instruction or command signal to the control terminal of the variable wavelength sweep type measurement light source 10 at a predetermined timing, thereby to cause the frequency of the optical signal generated from the measurement light source 10 to be swept within the predetermined frequency range.
Incidentally, an optical frequency bandwidth that can be covered by one sweep is determined by the performance of the variable wavelength sweep type measurement light source 10, and this bandwidth is approximately several 10 GHz or so in the current technology level. Accordingly, the wavelength of the optical signal generated from the measurement light source 10 will be changed, by sweep of the frequency, from a set reference wavelength which is the minimum (or the maximum) wavelength within the sweep wavelength range corresponding to the optical frequency bandwidth of the several 10 GHz or so, until the maximum (or the minimum) wavelength within that sweep wavelength range.
The optical transfer characteristic of the optical device under measurement DUT is first measured at the set reference wavelength of an optical measurement signal generated from the variable wavelength sweep type measurement light source 10, and next the frequency of the optical measurement signal of the measurement light source 10 is swept within the optical frequency bandwidth of several 10 GHz or so, so that the optical transfer characteristic of the optical device under measurement DUT can be measured at the set reference wavelength as well as at each of measurement points subsequent to the set reference wavelength spaced a constant distance or interval apart, which are determined by the resolution of the measuring apparatus (in other words, at each of optical frequencies corresponding to these measurement points). Therefore, the variable wavelength sweep type measurement light source 10 can perform its sweep operation with sufficiently high resolution in respect of that optical frequency bandwidth of several 10 GHz or so.
Further, as the variable wavelength reference light source 20, it is preferable to use a high precision light source which is capable of generating an optical signal having more precisely controlled reference wavelength as compared with the reference wavelength of the optical measurement signal generated from the variable wavelength sweep type measurement light source 10.
The operation of the optical transfer characteristic measuring apparatus constructed as mentioned above will be described with reference to a flow chart shown in FIG. 5.
First, in step SP1, a wavelength setting signal is supplied to both of the light sources 10 and 20 from the variable wavelength light source control part 80, thereby to set the wavelengths of the optical signals to be generated respectively from these light sources 10 and 20 to a specified identical reference wavelength, for example, xcex0 so that optical signals each having this reference wavelength xcex0 are outputted from both light sources.
The optical signal of the reference wavelength xcex0 generated from the variable wavelength sweep type measurement light source 10 is inputted to the optical device under measurement DUT and the second optical coupler 31 via the first optical coupler 30. The optical signal inputted to the optical device under measurement DUT is transmitted through this optical device under measurement DUT to the measurement/analysis/display part 90 so that an optical transfer characteristic of the optical device under measurement DUT is measured. On the other hand, the optical signal inputted to the second optical coupler 31 does not optically interfere with the optical signal generated from the variable wavelength reference light source 20 because the wavelength of the optical signal inputted to the second optical coupler 31 is the same, at this point in time, as the wavelength xcex0 of the optical signal outputted from the variable wavelength reference light source 20. As a result, the difference frequency between both the optical signals is zero, and hence no detected output is generated from the wide-band optical receiver 29. Accordingly, the amount of sweep on the optical signal outputted from the high frequency counter 50 is zero.
Next, the process proceeds to step SP2 in which the variable wavelength light source control part 80 supplies a frequency sweep instruction signal to the variable wavelength sweep type measurement light source 10, thereby to sweep the frequency of the optical signal outputted from the variable wavelength sweep type measurement light source 10 within a predetermined frequency range (optical frequency bandwidth of several 10 GHz or so).
When the sweep of the optical frequency is started, a detected output is outputted from the wide-band optical receiver 29. Accordingly, in step SP3, the detected output from the wide-band optical receiver 29 is measured by the high frequency counter 50. Based on the measured result, the measurement/analysis/display part 90 measures the amount of sweep of the optical frequency. Next, in step SP4, a decision is rendered whether the amount of sweep of the optical frequency has reached a limit of the ending side of sweep or not, that is, whether the frequency of the optical signal has been swept up to the upper limit (or the lower limit) of the predetermined frequency range or not.
During the time period that the amount of sweep of the optical frequency has not reached that limit (during the time period that the decision indicates xe2x80x9cNOxe2x80x9d), in step SP5, the optical transfer characteristic of the optical device under measurement DUT is measured at each of measurement points spaced a constant distance or interval apart starting at the set reference wavelength xcex0 (measured at each of optical frequencies corresponding to these measuring points), the constant distance being determined by the resolution of the measuring apparatus. The measurement at each of the measuring points is performed by repeating the steps SP2, SP3, SP4 and SP5.
On the contrary, in the step SP4, when the amount of sweep of the optical frequency has reached the limit of the ending side of sweep (YES), the process proceeds to step SP6 in which the sweep of the optical frequency of the optical signal having the reference wavelength xcex0 generated from the variable wavelength sweep type measurement light source 10 has been ended.
Next, the process proceeds to step SP7 in which the measurement/analysis/display part 90 analyzes the optical transfer characteristics of the optical device under measurement DUT at the reference wavelength xcex0 as well as at the measurement points (at each of the optical frequencies) ranging from the reference wavelength xcex0 to the upper limit or the lower limit within the predetermined frequency range, and displays or outputs the results of the measurement/analysis, if necessary. By this process, the measurement of the optical transfer characteristic of the optical device under measurement DUT has been completed.
As mentioned above, in the optical transfer characteristic measuring apparatus and method currently used, there are prepared, in order to measure the optical transfer characteristics of the optical device under measurement with high resolution on optical frequency axis or on optical wavelength axis, two types of light sources, one being the variable wavelength sweep type measurement light source 10 and the other being the variable wavelength reference light source 20, and the optical transfer characteristics of the optical device under measurement are measured while the sweep frequency on the optical measurement signal generated from the variable wavelength sweep type measurement light source 10 is being monitored by use of the optical heterodyne detection in which the optical signal generated from the variable wavelength reference light source 20 is used as a reference light.
However, the frequency bandwidth of the variable wavelength sweep type measurement light source 10 that can be covered by one frequency sweep is that of several 10 GHz or so, and hence there is a limitation in the sweep frequency bandwidth. Since a measurable optical frequency bandwidth is determined by this limitation in the sweep frequency bandwidth, the current optical transfer characteristic measuring apparatus and method cannot measure an optical transfer characteristic in wide optical frequency bandwidth with high resolution.
That is, as discussed above, the sweep frequency bandwidth of the optical signal generated from the variable wavelength sweep type measurement light source 10 is a bandwidth of only several 10 GHz or so. On the contrary, an operating frequency bandwidth of an optical device used in, for example, optical communications is much wider than the frequency bandwidth of several 10 GHz or so. Accordingly, there is a serious drawback that if an optical transfer characteristic of such optical device is measured by one frequency sweep of the variable wavelength sweep type measurement light source 10 and the optical transfer characteristic thereof is evaluated, the measured and evaluated results are unreliable. In other words, it is desirable to measure an optical transfer characteristic of an optical device on optical frequency axis or on optical wavelength axis in a wide sweep frequency bandwidth comparable to the wide frequency bandwidth of the optical device.
Moreover, in the technology of wavelength division multiplexing transmission (WDM) in recent years, there is a tendency that a distance between wavelengths is becoming more and more narrow. Therefore, the resolution on optical frequency axis must sufficiently be ensured. In addition, in case of performing a computation or operation such as a differential or the like and/or an analysis on the optical frequency axis, if the sweep frequency bandwidth is narrow, the amount of data in one time operation or computation (frequency bandwidth) determined at the time of the operation becomes discontinuous in the starting area or the ending area of the optical frequency axis. As a result, an operation or computation process error (measurement error) occurs in the starting area or the ending area of the optical frequency axis.
It is an object of the present invention to provide a method for measuring an optical transfer characteristic which is capable of measuring an optical transfer characteristic of an optical device on optical frequency axis or on optical wavelength axis in wide optical frequency bandwidth with high resolution.
It is another object of the present invention to provide an apparatus for measuring an optical transfer characteristic which uses the aforesaid optical transfer characteristic measuring method.
In order to accomplish the above objects, in a first aspect of the present invention, there is provided a method of measuring an optical transfer characteristic comprising the steps of: sequentially shifting an optical frequency band such that any discontinuous point in frequency does not occur, performing a sweep of an optical frequency over each of the respective optical frequency bands, and measuring an optical transfer characteristic of an optical device under measurement a plurality of times; and concatenating the measured data of the plurality of times on optical frequency axis.
The optical frequency bands sequentially shifted have an overlapped portion between two adjacent optical frequency bands, the overlapped portion being composed of a frequency band portion in the sweep ending side of one optical frequency band which is swept earlier in time and a frequency band portion in the sweep starting side of the other optical frequency band which is swept next time.
In a preferred embodiment, the sweep of the other optical frequency band which is swept next time is started at an optical frequency in the proximity of the sweep ending side of the one optical frequency band which is swept earlier in time.
In a second aspect of the present invention, there is provided a method of measuring an optical transfer characteristic comprising the steps of: (A) generating an optical signal having a specified first wavelength from a variable wavelength sweep type light source which is capable of switching stepwise the wavelength of an optical signal generated thereby and sweeping the optical frequency of the optical signal in a predetermined frequency range; (B) measuring an optical transfer characteristic of an optical device under measurement at the specified first wavelength; (C) sweeping the optical frequency of the optical signal having the specified first wavelength; (D) measuring the optical transfer characteristic of the optical device under measurement at each of the respective wavelengths corresponding to a predetermined plurality of optical frequencies during the sweep of the optical frequency of the optical signal; (E) ending the sweep of the optical frequency of the optical signal when the sweep optical frequency of the optical signal has reached a frequency corresponding to a specified second wavelength to be generated next time from said variable wavelength sweep type light source; (F) measuring the optical transfer characteristic of the optical device under measurement at the specified second wavelength to be generated next time; (G) sweeping the optical frequency of the optical signal having the specified second wavelength; (H) measuring the optical transfer characteristic of the optical device under measurement at each of the respective wavelengths corresponding to a predetermined plurality of optical frequencies during the sweep of the optical frequency of the optical signal; (I) ending the sweep of the optical frequency of the optical signal when the sweep optical frequency of the optical signal has reached a frequency corresponding to a specified third wavelength to be generated next time from said variable wavelength sweep type light source; (J) repeating the steps (F) to (I) with regard to each of specified wavelengths to be generated from the variable wavelength sweep type light source until the specified wavelengths to be generated therefrom have been completed; and (K) concatenating, on optical frequency axis or optical wavelength axis, the measured results of the optical transfer characteristic regarding all of the specified wavelengths generated from the variable wavelength sweep type light source.
A distance between the plurality of specified wavelengths generated from the variable wavelength sweep type light source and switched stepwise is chosen such that it is shorter than a distance corresponding to the sweep frequency bandwidth of the optical signal.
In a preferred embodiment, by sweep of the optical frequency of the optical signal, a wavelength range is swept, which starts at a predetermined wavelength in the side of a specified wavelength generated earlier in time than the associated specified wavelength, and extends therefrom through this associated specified wavelength to a specified wavelength generated next time.
By sweep of the optical frequency of the optical signal, a wavelength range may be swept, which starts at the associated specified wavelength, and extends therefrom through a specified wavelength generated next time to a predetermined wavelength beyond this next generated specified wavelength.
Alternatively, by sweep of the optical frequency of the optical signal, a wavelength range may be swept, which starts at a predetermined wavelength in the side of a specified wavelength generated earlier in time than the associated specified wavelength, and extends therefrom through this associated specified wavelength and a specified wavelength generated next time to a predetermined wavelength beyond this next generated specified wavelength.
The amount of sweep of the optical frequency of the optical signal is monitored by an optical heterodyne detection of an optical signal generated from the variable wavelength sweep type light source.
In a third aspect of the present invention, there is provided an apparatus for measuring an optical transfer characteristic comprising: a variable wavelength sweep type light source capable of switching stepwise the wavelength of an optical signal generated thereby and sweeping the optical frequency of the optical signal in a predetermined frequency range; light source control means for setting the wavelength of an optical signal generated from said variable wavelength sweep type light source to a specified wavelength as well as causing a sweep of the optical frequency of the generated optical signal having the specified wavelength over said predetermined frequency range to be carried out; first optical coupling means for inputting the optical signal generated from the variable wavelength sweep type light source into an optical device under measurement; measuring means optically coupled to said optical device under measurement for receiving an optical signal outputted from the optical device under measurement to measure an optical transfer characteristic of the optical device under measurement; counting means for counting the number of occurrence times of optical signals generated from the variable wavelength sweep type light source, the wavelength of each of said optical signals having been set to a specified wavelength; and means for ending the measurement of the optical transfer characteristic of the optical device under measurement, in response to a count signal outputted from said counting means when the number of occurrence times of optical signals each having a set specified wavelength has reached a preset number of times; and wherein said light source control means causing the variable wavelength sweep type light source to generate optical signals having their wavelengths sequentially switched and set to corresponding specified wavelengths as well as causing a sweep of the optical frequency of each of the generated optical signals having the corresponding specified wavelengths over said predetermined frequency range to be carried out, until the number of occurrence times of the optical signals each having a set specified wavelength reaches the preset number of times; and said measuring means concatenating, on optical frequency axis or optical wavelength axis, the measured results of the optical transfer characteristic regarding all of the specified wavelengths after the measurement of the optical transfer characteristic has been completed, and analyzing/displaying it.
In a preferred embodiment, the measuring apparatus further comprises: a variable wavelength reference light source capable of switching stepwise the wavelength of an optical signal generated thereby and incapable of sweeping the optical frequency of the optical signal; second optical coupling means into which are inputted an optical signal generated from said variable wavelength reference light source and an optical signal generated from said variable wavelength sweep type light source, and outputting an optical signal which has been optically heterodyned; and optical detecting means for detecting the optical signal outputted from said second optical coupling means to detect an electrical signal having an optical beat frequency; and wherein the wavelength of an optical signal generated from said variable wavelength reference light source is set to the same wavelength as the specified wavelength of an optical signal generated from the variable wavelength sweep type light source by the light source control means; said second optical coupling means optically heterodynes an optical signal of a specified wavelength generated from the variable wavelength reference light source and an optical signal. the wavelength of which is varied by a sweep of the optical frequency thereof, generated from the variable wavelength sweep type light source, and inputs the heterodyned optical signal into said optical detecting means; and the amount of sweep of the optical frequency is monitored on the basis of the electrical signal having an optical beat frequency detected by said optical detecting means.
In addition, the second optical coupling means optically heterodynes the optical signal generated from the variable wavelength sweep type light source and optically branched by the first optical coupling means, and the optical signal generated from the variable wavelength reference light source, and inputs the heterodyned optical signal into the optical detecting means.
Moreover, the measuring apparatus further includes: high frequency counting means for measuring the amount of sweep of the optical frequency on the basis of a detected output from the optical detecting means, and supplying the measured result to said measuring means; frequency-to-voltage converting means for converting a detected output from the optical detecting means into a voltage signal; a memory in which wavelength switching data are previously stored, the number of the wavelength switching data being equal to the number of specified wavelengths of optical signals generated from the variable wavelength sweep type light source, and the specified wavelengths being switched in one measurement; and voltage comparing means for comparing a voltage signal outputted from said frequency-to-voltage converting means with data read out of said memory; and wherein said counting means counts the number of occurrence times of optical signals generated from the variable wavelength sweep type light source, the wavelength of each of the optical signals having been set to a specified wavelength, by counting comparison result signals outputted from the voltage comparing means.

Method and apparatus for measuring an optical transfer characteristic


A container for dispersing liquid through a dispenser is described. The container has a resealable outlet which has an outlet passageway in a tube and a stop wedged in the passageway to seal the liquid in the container. The passageway is accessible beneath the stop by a dispenser peg for insertion in the tube to push the stop inward toward the interior of the container. A means for containing the stop is adjacent the passageway inlet. The stop reseals the passageway by covering the passageway inlet after a dispenser peg is removed from the passageway.

A known container and dispensing device is shown in the Unilever N.V.'s European patent no. 0369722. The container is formed of substantially rigid plastics material and has a special cap with a slit septum. The dispensing device has a support for the container in which is arranged a hollow peg through which is pumped the liquid. The container is mounted on the dispenser by inverting the container and allowing the peg to penetrate the septum. The liquid is then pumped out and dispensed from the device as required by the user. When the container is empty, it is removed and discarded, then replaced by a new, full container.
U.S. Pat. No. 3,952,918 describes another liquid dispenser system where an upstanding puncture tube punctures a seal to supply liquid to a hand-operated pump. The pump can dispense as much liquid as desired by rapidly pumping the system. The pump piston includes a check valve which, during the fill stroke of the pump, clears liquid from the dispenser nozzle.
International PCT Application W095/23549, now owned by Unilever N.V., describes a liquid dispenser where a check valve is used to prevent product dripping from a bag hopper when the hopper is removed from the dispenser to permit cleaning of the dispenser should a leak from the pierced bag occur.
Although these systems work extremely well, there are always pressures in business to reduce the costs of products, in particular where those products are disposable. It is therefore an object of an aspect of the invention to provide a simpler and therefore potentially less expensive container with less volume and weight of plastic to dispose of.

Liquid dispenser having a container with a dispensing device


A molding device for manufacturing a molded product having an inner space bent in a circular arc shape includes: a set of molds joinable to and separable from each other, the set of molds being capable of forming a cavity having a shape corresponding to an outer shape of the molded product in a joined state at the time of molding; a core having an outer shape corresponding to an inner shape of the molded product for use in a state where the core is arranged in the inside of the cavity formed by the set of molds at the time of molding; and an ejector plate having a core through hole through which the core passes for ejecting the molded product formed around the core along the circular arc shape in a separated state where the set of molds is separated from each other.

1. Field of the Invention
The present invention relates to a molding device and a method of manufacturing a molded product.
2. Description of the Related Art
Conventionally, in the technical field of molding (various cast moldings, injection molding and the like), a technique has been well-known where molding is performed using a core for manufacturing a molded product having an inner space. When the internal shape of a molded product is simple, the molded product can be molded and removed using a simple molding device even when a core is used. However, with respect to a molded product having an inner space bent in a circular arc shape as in the case of a part used as an intake manifold or the like, for example, a core and a molded product interfere with each other so that it is difficult to mold and remove a molded product using a simple molding device.
Conventionally, there has been known a molding device for manufacturing a molded product such as the above-mentioned molded product, that is, a molded product having an inner space bent in a circular arc shape (see JP-A-8-276259 (patent literature 1), for example).
FIG. 18A and FIG. 18B are views for explaining a conventional molding device 900. FIG. 18A is a perspective view of the molding device 900 after the molding is finished, and FIG. 18B is a side view of a core 930, a support member 940 and an ejector pin 950.
The conventional molding device 900 is, as shown in FIG. 18A and FIG. 18B, formed of a set of molds which is joinable to and separable from each other. The molding device 900 includes: a set of molds 910, 920 which can form a cavity having a shape corresponding to an outer shape of a molded product P0 in a state where the molds are joined to each other at the time of molding; a core 930 which has an outer shape corresponding to an inner shape of the molded product P0 and is used in a state where the core 930 is arranged in the cavity which the set of molds 910, 920 forms at the time of molding; a support member 940 which supports the core 930 from the outside; and an ejector pin 950 which is extensible and retractable one-dimensionally along the direction perpendicular to the direction along which the set of molds 910, 920 is separated from each other and ejects the molded product P0 formed around the core 930.
According to the conventional molding device 900, one set of molds 910, 920 is separated after molding. Then, the core 930 and the molded product P0 are separated from the mold 920 together with the support member 940. Thereafter, the molded product P0 is ejected by the ejector pin 950. Accordingly, the molded product P0 having an inner space bent in a circular arc shape can be removed.

Molding device and method of manufacturing molded product


A helical scanning operation is performed while a bed is moved, so that data by one-time rotation is collected while positional relationships between a detecting system and a phantom relatively are changed. Further, data obtained by scanning an air region and data obtained by scanning a water region are discriminated on the basis of positional information obtained by positioning scanning or the difference between the air and the water in X-ray absorptance, and correction data is created on the basis of the discrimination.

1. Field of the Invention
The present invention relates to an X-ray CT apparatus having multi-column detectors and a method of creating correction data for X-ray CT, and more particularly, to a technology that is used when creating correction data before photographing a diagnosis image.
2. Description of the Related Art
Generally, X ray CT apparatuses calculate (reconstructs) an X ray absorptance index of tissues, such as internal organs, as indexes or CT values, on the basis of an X ray absorption amount by which X rays are absorbed in a subject, and obtain images (tomographic images). These CT values are generally based on the X ray absorptance of water or air, and are corrected by using correction data so as to correspond to the reference values. Examples of a method of acquiring correction data include a method of acquiring correction data by projecting images again at a plurality of projection angles data from an output image (for example, JP-A-2002-191591), a method of creating a thomographic image from data that is collected by a spiral data collecting unit (for example, JP-A-10-192272), and a method of acquiring data obtained by performing adding and averaging processes on data obtained through rotation of n times as correction data (for example, JP-A-10-248301).
However, the following problems exist in the methods of acquiring correction data according to the related art.
That is, according to the method of acquiring the correction data in the related art, with development of multi-column X-ray detectors (for example, increase in the number of detecting columns), a size of a phantom also needs to be increased. However, it is difficult to set a phantom whose size is increased in a column direction (bed longitudinal direction) to a bed, which causes a large amount of working loads. Further, in order to hold a plurality of phantoms whose diameters are different according to the number of detected columns, a large amount of storage space is required, which is not practical.
Further, according to the methods in the related art, X ray absorptance is acquired by scanning a phantom filled with water. Further, in a state where a photographic subject, such as the phantom or the like, is not disposed, scanning is carried out to obtain X ray absorptance of air. Accordingly, in order to obtain the X ray absorptance of the water or the air, it is necessary to perform a scanning operation twice in a state where the phantom is not disposed and a state where the phantom is disposed, which causes a large amount of working loads.

X-ray CT apparatus and method of creating correction data for X-ray CT


The invention provides a method for serial data transmission. First, a chip select signal is enabled to a device for serial data transmission. Data stored in a first buffer of a controller is then transmitted to a second buffer of the device. A clock signal is then halted after data stored in the first buffer is completely transmitted. The first buffer is then refreshed with data newly received by the controller while the clock signal is halted. The clock signal is the restarted to operate the device after the first buffer is refreshed. Refreshed data stored in the first buffer is then transmitted to the second buffer while the clock signal is oscillating.

1. Field of the Invention
The invention relates to data transmission, and more particularly to Serial-Peripheral-Interface (SPI) data transmission.
2. Description of the Related Art
FIG. 1 is a block diagram of a conventional system 100 for Serial-Peripheral-Interface (SPI) data transmission. System 100 includes an SPI controller 110 and an SPI slave 120. The SPI controller 110 is also referred to as an SPI master. After the SPI controller 110 receives data from a Peripheral Component Interconnect (PCI) bus, the SPI controller 110 transmits the received data to the SPI slave 120 according to SPI standard.
A data signal, a clock signal, and a chip select signal are transmitted between the SPI controller 110 and the SPI slave 120. The data signal comprises data transmitted from the SPI controller 110 to the SPI slave 120 according to SPI standard. The SPI slave 120 operates according to the clock signal, and operation of the SPI slave 120 is suspended if the clock signal is halted. The SPI controller 110 may control multiple SPI slaves and must specify the SPI slave 120 as the transmission target in advance. Thus, the SPI controller 110 enables the chip select signal to select the SPI slave 120 before data transmission between the SPI controller 110 and the SPI slave 120 is started.
The SPI controller 110 includes a buffer 112, and the SPI slave 120 includes a buffer 122 and a memory 124. FIG. 2 is a schematic diagram of signals communicated between the SPI controller 110 and the SPI slave 120 of FIG. 1. The SPI controller 110 first enables the chip select signal corresponding to the SPI slave 120, as shown by mark 210 of FIG. 2. The SPI controller 110 first stores data received from a PCI bus in the buffer 112. The SPI controller 110 then transmits an access command 202 and an address 204 through the data signal, wherein the access command 202 may be a write command and the address 204 specifies the writing address of data.
The SPI controller 110 then outputs data stored in the buffer 112 to the SPI slave 120 through the data signal 206. When the SPI slave 120 receives the data output by the SPI controller 110, the SPI slave 120 temporarily stores the received data in the buffer 122. When the SPI controller 110 estimates that the buffer 122 of the SPI slave 120 is full or when the SPI controller 110 wants to end the transmission, the SPI controller 110 disables the chip select signal, as shown by mark 220 in FIG. 2. When the chip select signal is disabled, the SPI slave 120 moves data stored in the buffer 122 to a memory 124 thereof. Thus, a data-transmission cycle between the SPI controller 110 and the SPI slave 120 is complete.
The SPI slave 120 stores data of the buffer 122 into the memory 124 when the SPI controller 110 disables the chip select signal. Storing data into memory 124, however, requires time and delays data transmission. Thus, the SPI controller 110 disables the chip select signal when the buffer 122 of the SPI slave 120 is full to save the transmission time. To fill the buffer 122 of the SPI slave 120 in one data-transmission cycle, the size of the buffer 112 of the SPI controller 110 is the same as that of the buffer 122 of the SPI slave 120. The buffer sizes of the buffers 112 and 122 are both assumed to be 256 bytes. If the SPI controller 110 disables the chip select signal when 1-byte data is transmitted, the transmission of 256-byte data requires 211.98 seconds. If the SPI controller 110 disables the chip select signal after 256-byte data is transmitted to fill the buffer 122 of the SPI slave 120, transmission of 256-byte data only takes 2.58 seconds.
Although the buffer sizes of the buffers 112 and 122 are the same, the conventional SPI data transmission still presents some drawbacks, such as the larger the memory 124 of the SPI slave 120 is, the larger the buffer 122 is required. It means an SPI controller 110 should comply with a buffer of the same size. In other words, SPI slaves with buffers of different sizes require different SPI controllers with buffers of different sizes for data transmission, and an SPI controller with fixed buffer size cannot control multiple SPI slaves with buffers of different sizes. If an SPI controller 110 controls an SPI slave 120 with a buffer size exceeding that of the SPI controller, the SPI controller 110 enables the chip select signal when data of the buffer 112 is completely transmitted, but the transmitted data cannot fill the buffer 122 of the SPI slave 120, causing extra delays in data transmission. Thus, a method for solving the problem of SPI data transmission is required.

Method, system, and integrated chip for serial data transmission


A joint prosthesis includes a shaft part insertable into a tubular bone and a head part joining the shaft part and including a joint connection element. The head part includes a sleeve region having a through bore adapted to a cross section of a shaft of the joint connection element. The longitudinal axis of the shaft part and the joint connection element form an obtuse angle when the joint connection element is introduced into the through bore of the head part.

The invention relates to a modular joint prosthesis having a shaft part insertable into a tubular bone and a head part, adjoining the shaft part, and having a joint connection element, the longitudinal axes of the shaft part and joint connection element forming an obtuse angle.
Shaft prostheses of this kind are produced in various shapes and sizes, to assure that the needs of a given patient can be optimally met.
International Patent Application WO 85/05027 discloses an artificial joint system, in particular a hip joint prosthesis for cementless implantation, which has a shaft part that can be introduced into the upper thigh of the patient and a joint connection element connected to this shaft part. In the proximal region of the shaft part, a threaded sleeve is provided, into which the joint connection element is screwed; the longitudinal axis of the shaft part and the longitudinal axis of the joint connection element are inclined relative to one another. Accordingly, the joint connection element has a threaded peg, which on its proximal end is connected to a conical shaft part for receiving the ball of the joint. The process of screwing the prosthesis in is concluded once the conical shaft part of the joint connection element rests firmly on the proximal region, prepared for the implantation, of the upper thigh bone.
However, the above-described version has the disadvantage that only a complete replacement of the joint, including the ball of the joint, can be done with it.


A pixel architecture comprises: an absorption layer, which is configured to generate charges in response to incident light; a semiconductor charge-transport layer, which is configured to transport the generated charges through the charge-transport layer, wherein one or more doped regions are arranged in the charge-transport layer, wherein the charge-transport layer comprises a bias region and a charge-dispatch region being associated with the bias region; an electric connection connecting to and providing a selectable bias voltage to the bias region; and at least one transfer gate, wherein the doped regions and the bias region are differently biased for driving transport of the generated charges towards the charge-dispatch region, and for controlling, together with the at least one transfer gate, transfer of charges from the charge-dispatch region to a charge node.

In some imaging applications, it is important to acquire information in a very short time period. For instance, this may be important for imaging of high speed events, which may e.g. be used in fluorescence microscopy to detect a timing of induce fluorescence.
In depth or distance sensing applications, there is also a need to acquire information in a very fast manner. Such applications may make use of time-of-flight (TOF), i.e. by determining a point in time when a light pulse reflected by an object is received by an image sensor a distance to the object may be determined. TOF applications may make use of a light pulse that has a very sharp edge. The light pulse or an edge of the light pulse may have a very short duration, such as in the order of nanoseconds or even shorter, which implies that a high resolution of the depth or distance sensing may be obtained.
For TOF applications, a sequence of light pulses may be provided. The acquiring of information may be synchronized with the sequence of light pulses, such that charges generated by the pulses are accumulated so that an integration of information may be performed over a plurality of light pulses in the sequence, so-called lock-in sensing. This may enable an improved signal-to-noise ratio of the TOF sensing.
However, in order to enable acquiring of image information in a fast manner, as desired for TOF applications, an image sensor needs to have pixels that may transfer charges within pixels in a very fast manner in order to acquire information and quickly make the pixel ready for sensing new information.
In US 2011/0187908, there is disclosed a high-speed charge-transfer photodiode encompassing a first conductivity type semiconductor layer serving as a charge-generation region; and a second conductivity type surface-buried region serving as a charge-transfer region of charges generated by the charge-generation region, wherein a specified direction in the surface-buried region provided along a plane parallel to a surface of the semiconductor layer is assigned as a charge-transfer direction of the charges, and at least one of a variation of widths of the surface-buried region measured in an orthogonal direction to the charge-transfer direction and a variation of impurity concentration distributions of the surface-buried region, which are measured along the charge-transfer direction, is determined such that an electric field distribution in the charge-transfer direction is constant.
The structure of US 2011/0187908 however requires an accurate control of the widths of the surface-buried region or the variation of impurity concentration distributions of the surface-buried region in order to achieve the constant electric field distribution, which imposes accurate control requirements on a manufacturing process for producing the structure. Further, a strength of an electric field that can be induced, for driving transport of charges, is limited and hence a speed of collection of charges in a charge-collection region is limited.


A twin well forming method for a semiconductor device includes the steps of forming a first insulation layer on a semiconductor substrate, selectively etching the first insulation layer to obtain a first insulation layer pattern and a first buffer insulation, ion-implanting first impurities through the first buffer insulation layer into the semiconductor substrate, forming a second insulation layer on the first insulation layer pattern and the first buffer insulation layer, spreading a planarizing material on the second insulation layer and applying the planarizing material to an annealing treatment to obtain a planarizing material layer, etching back the planarizing material layer and the second insulation layer to expose an upper surface of the first insulation layer pattern, forming a second buffer insulation layer by partially etching the first insulation layer pattern, ion-implanting second impurities through the second buffer insulation layer into the semiconductor substrate, removing the second insulation layer, the first buffer insulation layer and the second buffer insulation layer, and annealing the semiconductor substrate. The method prevents the upper surface of the semiconductor substrate from being stepped or becoming uneven during the twin well formation, thereby improving a product reliability.

1. Field of the Invention
The present invention relates to a semiconductor device, and more particularly to an improved twin well forming method for a semiconductor device which prevents an uneven surface of a semiconductor substrate during a twin well formation, thereby enhancing a product reliability.
2. Description of the Background Art
FIGS. 1A through 1H are cross-sectional views sequentially illustrating a twin well forming method for a semiconductor device according to the conventional art.
As shown in FIG. 1A, on a semiconductor substrate 1 there is formed a first silicon oxide layer 2. A silicon nitride layer 3 is formed on the first silicon oxide layer 2.
In FIG. 1B, a photoresist pattern 4 is formed on the silicon nitride layer 3. Using the photoresist pattern 4 as a mask, the silicon nitride layer 3 is etched to form a silicon nitride layer pattern 3a. At this time, an upper surface portion of the first silicon oxide layer 2 is externally exposed through the etched hole.
Then, in FIG. 1C, phosphorus ions 5 are implanted through the exposed first silicon oxide layer 2 into the semiconductor substrate 1.
As illustrated in FIG. 1D, the exposed first silicon oxide layer 2 is selectively oxidized at a high temperature to obtain a second silicon oxide layer 6. At this time, the phosphorous ions 5 implanted into the semiconductor substrate 1 drive-in downwardly in the semiconductor substrate 1.
Referring to FIG. 1E, the silicon nitride layer pattern 3a is removed by an etching.
Next, as shown in FIG. 1F, using the second silicon oxide layer 6 as a mask, boron ions 7 are implanted through the first silicon oxide layer 2 into the semiconductor substrate 1.
As shown in FIG. 1G, the semiconductor substrate 1 is annealed to drive-in the boron ions 7 downwardly in the semiconductor substrate 1. At this time, the phosphorous ions 5 are further diffused downwardly in the semiconductor substrate 1.
Finally, as shown in FIG. 1H, the first silicon oxide layer 2 and the second silicon oxide layer 6 are removed from the semiconductor substrate 1 to realize the conventional twin well formation for a semiconductor device.
However, the conventional twin well forming method for a semiconductor substrate causes an uneven, stepped surface on the semiconductor substrate, thereby deteriorating a reliability of the semiconductor device.

Twin well forming method for semiconductor device


A cylindrical standard shank is provided for rotating cutting tools for locating a standard shank in a cylindrical location opening, precisely produced with regard to shape and true-running accuracy, in the work spindles of so-called transfer lines or of, for example, steep-taper adaptors. The cutting tool is, in turn, fixed by a cylindrical press connection in the standard shank serving as an adaptor between the tool shank and standardized location opening. The standard shank has, at the front, a longitudinally slotted clamping sleeve accurately machined on the inside and outside. The clamping sleeve is clamped by an accurately machined shrink collar of shape-memory alloy which is approximately the same length and has at least the same wall thickness, is present in the austenitic structural state at room temperature and in the process is reduced in diameter on account of suitable pretreatment, and bears tightly against the periphery of the clamping sleeve. The shrink collar can be transformed into the martensitic structural state by undercooling and can thereby be widened in diameter, as a result of which the clamping sleeve is relieved and the cutting tool located in the standard shank can be exchanged.

The present invention relates to a cylindrical standard shank and method for rotating cutting tools and, more particularly, to a cylindrical standard shank used in industrial large-scale machining production with transfer lines.
In industrial large-scale machines applications of this type, the many work spindles to be tooled are preferably provided with standardized location openings for direct location of the cutting tools in order to avoid expensive chucks, a loss of clamping accuracy and avoid true-running errors. A high true-running accuracy is important in order to be able to achieve long tool life of the cutting tools. However, so that the cutting tools, which vary quite a lot in size, can be inserted into the standardized location openings, a standard shank serving as an adaptor must in each case be attached to the tool shank of each cutting tool. In such arrangement, the mutual connection must, of course, be realized with the greatest possible true-running accuracy and high clamping force and in a low overall volume.
In the case of conventional standard shanks, the cutting tool must be brazed or adhesively bonded into place in the location bore of the standard shank. Neither the brazed nor the adhesively bonded connection can be released again in such a way that the standard shank could be reused. Alternatively, the cutting tool must be pressed by a very tight press fit into the standard shank location bore, which is produced undersize, or the location bore of the standard shank must be shrunk onto the shank of the cutting tool by heating and subsequent cooling, so that the cutting tool can no longer be non-destructively removed therefrom.
The abovementioned locating techniques for a cutting tool are certainly very space-saving and have sufficient true running accuracy if the working surfaces of the cutting tool are ground in the tool grinding machine only after the cutting tool is inserted and fixed in the standard shank and upon location of the entire tool on the joining cylinder of the standard shank. In all these cases, however, the standard shank must also be scrapped after complete wear or fracture of the cutting tool. In addition, brazing the cutting tool in place can only be realized in the case of certain tool materials, namely carbides, and even in the case of these materials only by tolerating certain structural impairments.
Clamping the cutting tools in the standard shank with a collet, although conceivable, would not be suitable in practice, since such clamping can reproduce only too low a true-running accuracy, produces inadequate fixing of the cutting tool in the standard shank, and could be realized at adequate stability only with a large overall volume, especially radially.
The same reasons also apply in principle to the clamping of the cutting tools in a standard shank with a metal collar which can be acted upon hydraulically (cf., e.g., German Offenlegungsschrift 3,909,630 or German Patent No. 2,639,320), where the disadvantages of a large overall volume and a cutting tool mounting arrangement, floating within limits, especially becoming apparent. Furthermore, uniformly maintaining the hydraulic clamping pressure at a high level over the entire life of the cutting tool is here very problematic and is not truly achieved in practice.
It would also be conceivable to effect the clamping of the cutting tool in place in the standard shank with a so-called whistle-notch connection, as is also provided for clamping the standard shank in place in the work spindle of the machine tool. Such a whistle notch is formed by a sloping face on the shank periphery, which sloping face is slanted by about 2.degree. to the inside and on which a grub screw acts which is arranged orthogonally thereto in the wall of the work spindle. This joining technique is, however, only suitable for larger shank diameters. Besides, for spindle-side clamping, it represents, on one hand, an unavoidable compromise between the demands for high true-running accuracy, here only just justifiable, and quicker as well as simpler releasability of the clamping using, on the other hand, available conventional workshop techniques.
Using a whistle-notch connection once again in the same tool-clamping arrangement would allow the unavoidable true-running errors to accumulate to an inadmissibly large degree. In addition, the connection between cutting tool and standard shank is not to be releasable with simple workshop techniques. For these reasons, the use of so-called whistle-notch connections between the cutting tool and standard shank is not suitable.
An object of the present invention is to improve the standard shank and to provide a method to the effect that the cutting tool can certainly be easily located, in a releasable manner, to be clamped, and consequently the standard shank can easily be used again repeatedly. Nonetheless, with a small overall volume of the clamping device, the cutting tool can be held in position with high retaining force and at a high, reproducible true-running accuracy in accordance with the present invention. In addition, the tool life is on no account to be impaired by the nature of the novel tool clamping but is to be advantageously influenced if at all possible.
This object has been achieved according to the invention by providing that unitarily connecting the standard shank having a thin-walled clamping sleeve in the front axial area of the location bore to a remaining portion of the standard shank and provided at a periphery thereof with a cylindrical outer surface of defined outside diameter, pushing a shrink collar of a shape-memory alloy configured to be onto the clamping sleeve, an axial length of said shrink collar approximately corresponding to, at most, an axial length of the clamping sleeve wherein the shape-memory alloy is selected with regard to its composition (alloy type) such that an its austenite finishing temperature thereof is below a working temperature, and passing the shrink collar through manufacture-induced states to achieve an intended function thereof. These states include working an inner surface of the shrink collar facing the clamping sleeve starting from an austenitic structural state to a clear undersize relative to an outside diameter of the clamping sleeve so that high pre-tension theoretically results when the shrink collar is paired with the outer surface of the clamping sleeve, expanding the shrink collar, subsequently transformed by undercooling into a martensitic structural state, in the peripheral direction such that the diameter of the inner surface of the shrink collar in the martensitic structural state has a slight oversize relative to the clamping sleeve, and selectively displacing the shrink collar on the clamping sleeve.
Accordingly, the releasability of the cutting tool from the standard shank is provided through the use of the collet principle, which is known per se but for several reasons is inadequate in conventional design, for the present tool clamping. Nonetheless, the high clamping force which can thereby be achieved and the reproducibly high clamping accuracy at a small radial overall volume surprisingly result from the use of a shrink collar of known shape-memory alloy. On account of the high clamping pressure uniformly effective over the entire intrados (inner arch) surface of the clamping sleeve, the accuracy of the intrados surface can become fully effective during the tool clamping.
During transformation, produced by heating, of the material structure of the shrink collar from martensitic (undercooled) into austenitic (room temperature), the shrink collar shrinks in diameter on account of the shape memory of the alloy. In the course of this shrinkage, the collar bears on the outside of the clamping sleeve with high force. Due to the high true-running accuracy, residual out-of-balance effects and thus the excitation of out-of-balance vibrations of the tool are very slight, which has an advantageous effect on the machining accuracy and the tool life.
In addition, the tool clamping arrangement according to the present invention has proved to have an astonishingly good vibration-damping characteristic, which likewise improves the machining accuracy and the tool life. The vibration-damping effect comes about, on one hand, through the two concentric, cylindrical fitting-surface pairs on account of a clamping hysteresis and, on the other hand, on account of the good damping property of the shrunk collar shape-memory material itself.
When the invention is widely used in large-scale machining production of a large company, a great number of advantages are obtained. For instance the standard shank can easily be used again upon fracture or after complete utilization of the regrinding reserve of the cutting tool located therein. On account of the standard shank roughly twice as expensive by itself compared with the unit price of the cutting tool and on account of the reusability of the standard shank, there is a great savings potential when there are a large number of standard shanks in a large-scale production. Despite the releasability of the cutting tool, it can be clamped in place in the standard shank or held in position therein at a reproducibly high true-running accuracy and high retaining force. Since the tool clamping takes place at temperatures at which the material structure of all conventional cutting-tool materials remains completely unchanged (i.e. low temperatures) and also no phases of high thermal expansion are passed through, tools made of all conceivable materials, in particular the relatively inexpensive high-speed cutting steel or the especially wear-resistant cutting ceramics, can be clamped with the standard shank according to the present invention.
Compared with conventional change clamping tools, the standard shank of the present invention provides (1 ) an unequalled high retaining force; (2 ) an unequalled high true-running accuracy (<15.mu.m) which can be reproduced even after repeated clamping; (3) an unequalled low overall volume, particularly in a radial respect, which is especially important for machining in restricted surroundings of a workpiece; (4) high damping action of the shrink collar, made of shape-memory alloy, against radial vibrations; (5) independently thereof, a damping effect through two joining surface pairs, lying concentrically one inside the other, on account of a clamping hysteresis; (6) on account of the high damping effect of the tool-clamping arrangement against radial vibrations of the tool, longer tool life can be achieved with this tool-clamping arrangement than with known tool-clamping arrangements having less effective damping; (7) the clamping connection between cutting tool and standard shank can be released relatively simply undercooling by placing in dry ice (CO.sub.2) or immersing in liquid nitrogen, but it cannot be released, not even inadvertently, by the machine operator of a transfer line using the conventional workshop techniques in-situ there, so that there is a tool-clamping arrangement which is reliable for a long period; (8) standardized cutting tools, which are thus less expensive and can subsequently be delivered at short notice, can be located and fixed in the already finish-ground state in the standard shank by the customer or user of the tools so that costly stock-keeping, planned for the long term, of expensive special tools at the user's can be dispensed with; and (9) the standard shank, if it is hollow-drilled, permits reliable and loss-free conduction of cooling and lubricating emulsion without a separate seal through the clamping arrangement of the cutting tool.
German Offenlegungsschrift 3,007,307, for example, certainly discloses reversibly releasable shrink connections with the use of shrink collars of shape-memory alloy, but here this concerns the connection of abutting cylindrical parts, in particular tubes, which are connected by a shrink collar resting directly on the two tube ends and bridging the joint. In view of the high accuracy requirements for tool-clamping arrangements, it could not be foreseen by the person skilled in the art and active in this field that the shrink connection known from the field of steel construction, when applied to a collet, which does not produce the necessary clamping accuracy for the present use, is nonetheless completely satisfactory here with regard to all requirements to be met. Therefore, application to a completely different field in a modified use of the shrink collars of shape-memory alloy must be considered to be original, technically unconventional and outstanding.
By the length restriction of the longitudinal slots of the clamping sleeve, the clamping arrangement of the tool shank of the present invention is to be effectively sealed off against loss or premature escape of cooling and lubricating emulsion.

Standard shank and method for directly locating rotating cutting tools in a machine tool work spindle


An optical line terminal transmitter front-end, an optical network terminal receiver front-end and a bit-interleaved passive optical network (BIPON). In one embodiment, the transmitter front-end includes: (1) a bit interleaver configured to group and interleave a plurality of user bit-streams to yield a combined single bit-stream, (2) an encoder coupled to the bit interleaver and configured to encode multiple bits of the single bit-stream into a multi-level code corresponding to a 2m-level multi-level signal and (3) a multi-level modulator coupled to the encoder and configured to modulate the multi-level code into the 2m-level multi-level signal.

Optical telecommunication networks have been widely built out in recent years and are gaining in popularity. Optical fibers are capable of carrying a high volume of traffic at a reasonable cost. Although previously the "last mile" between an optical communication network and the end user was still spanned with copper wire, now fiber optic cables are often run directly up to houses, apartment complexes, and business locations. One arrangement for spanning this portion of the communication link is referred to as a PON.
Generally speaking, a PON includes an optical line termination (OLT), typically located in a central office, which communicates via a fiber-optic cable system with one or more optical network units (ONUs), with each ONU being located on or near a customer premises. An optical network termination (ONT) is an ONU that typically serves a single user and may, for example, be located at the user's residence. A multi-dwelling unit (MDU) is an ONU that serves a multi-dwelling unit such as an apartment complex or small business. Each ONU is capable of segregating the downstream signals from the OLT and directing them to the proper user, and of transmitting upstream signals back to the OLT. In addition to forming a part of one or more PONS, the OLT is also connected to the larger telecommunication system through which the various services such as telephony, Internet access, and broadcast media are accessible so that they can be made available to the users associated with the OLT.
Standards have been promulgated for PON operations. For example, many current implementations are configured in accordance with a family of specifications including ITU-T G.984 and related standards. Such systems currently provide for transmission speeds of up to (approximately) 2.5 Gbps in the downstream direction and 1.24 Gbps upstream. The directional difference in transmission speeds is due in part to practical consideration of the cost of facilitating higher upstream transmission speeds, coupled with the fact that, as a general rule, more content needs to be transmitted downstream than back to the OLT.
With increased utilization of optical network services, however, a need exists to increase existing aggregated date rate, at least in the downstream direction and eventually in both directions. One solution, of course, is simply to replace or upgrade all PONs and related equipment with the components necessary to accommodate the higher aggregated date rate. This, however, may be too expensive or difficult, especially in the near term.
For example, the best existing solution in supporting a higher aggregated date rate is a tunable wavelength division multiplexing (TWDM) PON, e.g., ITU-T NGPON2. Unfortunately, this solution requires a WDM filter at the OLT and/or array waveguide gratings (AWGs) in the optical distribution network (ODN) and tunable lasers in the ONT. Apart from the high component cost of each AWG, the WDM filter and the tunable laser, replacing conventional optical power splitters with AWGs in the ODN is costly.

Circuit and method for optical bit interleaving in a passive optical network using multi-level signals


According to the present invention, there is provided a semiconductor device fabrication method comprising:                forming a first insulating film on a semiconductor substrate;        forming a first conductive layer on the first insulating film;        forming a second insulating film on the first conductive layer in a first processing chamber isolated from an outside;        performing a modification process on the second insulating film in the first processing chamber, and unloading the semiconductor substrate from the first processing chamber to the outside;        annealing the second insulating film in a second processing chamber; and        forming a second conductive layer on the second insulating film.

The present invention relates to a semiconductor device and a method of fabricating the same.
Conventionally, a NAND flash memory has been developed as a nonvolatile semiconductor memory. A memory cell transistor of this NAND flash memory has a structure in which a floating gate electrode formed on a semiconductor substrate via a tunnel insulating film and a control gate electrode formed on this floating gate electrode via an inter-electrode insulating film are stacked.
Recently, to decrease the cell size, a method of using an alumina (Al2O3) film, instead of the conventional ONO film (a stacked film in which a silicon oxide film, silicon nitride film, and silicon oxide film are stacked), as an inter-electrode insulating film is proposed (reference 1).
Since the alumina (Al2O3) film is a high-dielectric-constant film having a relative dielectric constant higher than that of the ONO film, the area of the inter-electrode insulating film can be reduced. As a consequence, the cell size can be decreased.
The NAND flash memory stores "1" data in the memory cell transistor by discharging electrons from the floating gate electrode to the semiconductor substrate, and stores "0" data in the memory cell transistor by injecting electrons into the floating gate electrode from the semiconductor substrate.
Unfortunately, the density of a high-dielectric-constant film is low. Therefore, if a high-dielectric-constant film is used as the inter-electrode insulating film, electrons injected into the floating gate electrode from the semiconductor substrate by applying an electric field of a predetermined level between the control gate electrode and semiconductor substrate penetrate through the inter-electrode insulating film. This increases a leakage current flowing through the control gate electrode.
To prevent this, therefore, it is necessary to suppress the leakage current by performing a predetermined heating process (annealing) for a high-dielectric-constant film deposited on a conductive layer serving as the floating gate electrode, thereby modifying the high-dielectric-constant film.
The reference concerning the use of the alumina (Al2O3) film as the inter-electrode insulating film is as follows.    Reference 1: Symposium on VLSI Technology Digest of Technical Papers, p. 117, 1997

Method of fabricating a semiconductor device


An exercise apparatus is provided. The exercise apparatus includes first and second base assemblies, each having a plurality of riser segments. A first rail is connected to and spans the first and second base assemblies. The first rail has a plurality of horizontal segments interspersed with a plurality of vertical segments. A second rail is spaced apart from the first rail and is connected to and spans the first and second base assemblies. The second rail has a plurality of horizontal segments interspersed with a plurality of vertical segments. The horizontal and vertical segments of the second rail correspond to the horizontal and vertical segments of the first rail. Adjacent horizontal segments of each of the first and second rails are vertically spaced apart.

Conventional floor-based gymnastic apparatus can include the non-limiting examples of pommel horses, balance beam, parallel bars, uneven bars, rings and the like.
A conventional parallel bar apparatus includes two parallel, linearly arranged bars that are held parallel to, and elevated above, the floor by a metal supporting framework. The bars are composed of wood or other material, with an outer coating of wood. The supporting framework typically includes vertical members that may be adjustable in order that the height of the two parallel bars above the floor and the distance between the two parallel bars can be set optimally for each gymnast.
It would be advantageous if floor-based exercise apparatus could be developed for improved strength, stamina, flexibility and coordination.


While a PCI master on an external bus is executing a transaction on an internal PCI bus, if a bus access request signal (REQ#) output from a PCI device on the internal PCI bus, priority of which is higher than that of the PCI master, is asserted, a PCI bus arbiter deasserts a bus access enable signal (GNT#) corresponding to the PCI master. A request and grant manager informs the PCI master of GNT# by using a serial GNT# through an external PCI bus bridge connected to the internal PCI bus and the external PCI bus. Before the transaction executed by the PCI master ends, when the external PCI bus bridge recognizes that a device on the external PCI bus is a target specified by a transaction of the PCI device as a new bus master, it informs the PCI device of a target retry.

Standard system buses, such as ISA (Industry Standard Architecture) and EISA (Extended ISA) buses, are conventionally used in personal computers. Another standard bus, PCI (Peripheral Component Interconnect) bus, is commonly employed in desktop-type personal computers to increase the speed of data transfer and organize system architecture, independently of the kind of processors.
Substantially all data transfer using a PCI bus is block transfer, where each block is transferred by burst transmission. For example, data can be transferred at a transfer speed of 133 megabytes/sec. on a data bus having a width of 32 bits.
Therefore, when a PCI bus is used, data transfer between I/O devices and between a system memory and an I/O device is executed at high speed. As such, system performance is high.
Recently, PCI buses have been used not only in desktop-type personal computers, but also in portable personal computers, such as notebook-type computers.
In desktop type personal computers, option cards for function expansion, such as PCI expansion cards and ISA expansion cards, are directly mounted in an expansion slot on the system board. In such cases, a plurality of pairs of DMA request signal (DREQ) lines and DMA acknowledgment (DACK#) lines corresponding to a plurality of types of DMA channels are defined for each ISA expansion slot to which an ISA expansion card is connected (one pair of lines per slot). As a result, because each ISA expansion card uses a specific DMA channel corresponding to one combination of DREQ and DACK#, the DMA transfer function of a DMAC (direct memory access controller) core on the system board is executed.
Moreover, each PCI expansion slot to which the PCI expansion card is connected (one pair of lines per slot) defines a pair of arbitration control lines composed of a bus access request signal (REQ#) line and a bus access enable signal (GNT#) line. In this case, a PCI bus arbiter on the system board can arbitrate bus accesses of the PCI expansion cards as well as those of PCI devices on the system board.
Consequently, devices that do not require a DMA transfer function, such as PCI bus masters, and devices that do require a DMA transfer function, such as ISA devices, are easily combined in a desktop-type personal computer.
However, even in portable personal computers, it is necessary to mount option cards, such as PCI expansion cards and ISA expansion cards, via an expansion unit known as a desk station. In such a case, it is necessary to reduce as much as possible the number of signal lines leading out from the portable personal computer to the desk station. This is because an increased number of signal lines leading out to the desk station leads to an undesirable increase in the number of pins of the LSI circuit mounted on the system board for interfacing with the desk station, as well as an undesirable increase in the number of pins of the connector for connecting the portable personal computer and the desk station. These increases, in turn, result in an increase in the cost of the portable personal computer and reduction of system mounting efficiency.
As a result, computer systems are not commercially implemented with a plurality of pairs of DMA request signal (DREQ) lines and DMA acknowledgment (DACK#) lines and also a plurality of pairs of bus access request signal (REQ#) line and bus access enable signal (GNT#) lines leading out to the desk station. However, if control lines for DMA transfer are not provided to the desk station, option cards, such as ISA cards, cannot perform DMA transfers. Further the PCI expansion cards cannot serve as a bus master.
A computer system has been recently proposed that utilizes a protocol for transmitting and receiving DMA request signals (DREQ) and DMA acknowledgment (DACK#) signals between an ISA expansion card installed in the desk station and the DMAC core on the system board, and also for transmitting and receiving REQ# and GNT# between a PCI expansion card and the PCI bus arbiter, without using a plurality of pairs of DMA request signal (DREQ) lines and DMA acknowledgment (DACK#) lines and a plurality of pairs of bus access request signal (REQ#) lines and bus access enable signal (GNT#) line.
This protocol uses a pair of signals consisting of a bus access request signal (REQ#) and a bus access enable signal (GNT#) on a PCI bus, to recognize the transferring of DREQ and DACK# between an ISA expansion card and the DMAC core, and also the transferring of REQ# and GNT# between a PCI expansion card and the PCI bus arbiter. Thus, this protocol supports DMA requests (DREQs) for a plurality of channels and requests (REQs#) from PCI bus master in the pair of signals. Hereafter, REQ# and GNT# used for a serial transfer are designated serial REQ# and serial GNT#.
When the above-mentioned DMA serial channel protocol, which serially transfers a plurality of DMA requests and a plurality of PCI bus master requests in this way, is implemented in a bridge interface in the desk station to couple an external PCI bus and an external ISA bus, the bridge interface needs only signal lines corresponding to a PCI bus leading out to the desk station. Hence, it is possible to use both PCI expansion cards and ISA expansion cards.
However, the bridge within the desk station needs a process for serializing DMA request signals (DREQ) of a plurality of channels and PCI bus master request signals (REQs#), and a process for converting in parallel the serialized DREQ channel information transmitted by a serial transfer way in the DMAC core, and inputs the converted information to the ISA expansion cards and the PCI expansion cards in the desk station, with respect to the notification of the DMA acknowledge (DACK#) and the bus access enable signal (GNT#). Therefore, substantial time is required from generation of a DMA request signal (DREQ) and a PCI bus master request signal (REQ#) from the ISA and PCI expansion cards to reception of the DMA request signal and the PCI bus master request signal by the DMAC core and the PCI bus arbiter.
Similarly, the DMAC core needs a process for serializing DACK# signals of a plurality of channels and GNT# signals transmitted by a serial transfer way, and a process for converting in parallel the serialized information transmitted by a serial transfer way to two or more DACK# signals and GNT# signals, and inputs the converted information to the DMAC core and the PCI bus arbiter, with regard to notification of DMA request signals (DREQ) and PCI bus master request signals (REQ#). Therefore, similarly, substantial time is required from generation of a DMA acknowledgment signal (DACK#) and a PCI bus access enable signal (GNT#) from the DMAC core and the PCI bus arbiter to reception of the DMA request signal and the PCI bus master request signal by the ISA and PCI expansion cards, respectively.
The time lag in such serial transfer causes various problems. This is illustrated by the foregoing description of a conventional mechanism receiving transactions from two bus masters that collide due to the transmission delay of the bus access enable signal (GNT#).
(1) A PCI expansion card on an external PCI bus asserts a bus access request signal (REQ#) to request the PCI bus access on an internal PCI bus.
(2) If a bridge in a desk station, coupled to the internal PCI bus and the external PCI bus, receives the REQ#, the bridge transfers the REQ# to a PCI bus arbiter on a system board in a serial transfer way.
(3) The PCI bus arbiter transfers a bus access enable signal (GNT#) corresponding to the bus access request signal (REQ#) to the bridge in a serial transfer way, based on the result of the bus arbitration.
(4) The bridge accesses GNT# out of serial information transferred in a serial transfer way, and transmits it to the PCI expansion card, which is requesting the PCI bus access on the internal PCI bus.
(5) After the PCI expansion card receives GNT# from the bridge, it serves as a bus master to begin the transaction.
(6) When a PCI device on the internal PCI bus, the priority of which is higher than that of the PCI expansion card, asserts a bus access request signal (REQ#) during the execution period of the transaction, the PCI bus arbiter deasserts the bus access enable signal (GNT#) of the PCI expansion card, and transmits it to the bridge in a serial transfer way. The PCI bus arbiter asserts a bus access enable signal (GNT#) of the PCI device with high priority active.
(7) The bridge accesses the information that shows inactive GNT# from serial information transferred in a serial transfer way, and transmits it to the PCI expansion card. When the PCI expansion card recognizes that the GNT# is deasserted, it processes a present cycle of the transaction as the final cycle.
(8) On the other hand, the PCI device on the internal PCI bus, the GNT# of which a PCI device is asserted, begins the operation as a bus master. At this time, if the access of the PCI device is a target on the external PCI bus, the transaction executed by the PCI device is sent to the external PCI bus by way of the bridge.
(9) As mentioned above, the serial transfer of GNT# requires a lot time for a delay by the processing of the parallel-serial conversion and the serial-parallel conversion. Hence, the transaction of the PCI device on the internal PCI bus is transmitted to the external PCI bus by way of the bridge before the PCI expansion card ends the operation as a bus master.
(10) In this case, there is a collision between the transaction executed by the PCI expansion card and the transaction executed by a PCI device of which GNT# is newly asserted. The bridge cannot respond to the transaction from the PCI device of which GNT# is newly asserted until the transaction of the PCI expansion card ends. Therefore, the PCI device that began the transaction determines that there is not a target on the external PCI bus. This causes a master abort. If a master abort occurs at this time, the same transaction executed by the PCI device is not reexecuted.
Therefore, the conventional computer system, to which the DMA serial channel protocol is applied, contains a delay in the GNT# transmission to the PCI expansion card. Thus, the situation results in the transactions colliding.

Method and apparatus for controlling a master abort in a computer system