A means and method are disclosed for multiplexing a plurality of samples from multiple sprayer devices to be efficiently transferred to a mass analyzer for subsequent analysis. Sample sprays are formed from a plurality of sprayers, which are desolvated to form the sample ions. The sample ions are then selected from one of the sprayers for transportation into a mass analyzer. To accomplish this, the apparatus of the invention comprises a multi-part capillary wherein a first section thereof is connected to a motor which is able to move this first section from one sprayer to the next. This first section may be a flexible tube-like structure loosely mounted in an aperture of a cone-shaped end of a motor which rotates such that the sampling orifice may be aligned with different sprayers at different times to sequentially and repetitively sample ions produced by each of the plurality of sprayers.

Mass spectrometry is an important tool in the analysis of a wide range of chemical compounds. Specifically, mass spectrometers can be used to determine the molecular weight of sample compounds. The analysis of samples by mass spectrometry consists of three main steps—formation of gas phase ions from sample material, mass analysis of the ions to separate the ions from one another according to ion mass, and detection of the ions. A variety of means exist in the field of mass spectrometry to perform each of these three functions. The particular combination of means used in a given spectrometer determine the characteristics of that spectrometer.
To mass analyze ions, for example, one might use a magnetic (B) or electrostatic (E) analyzer. Ions passing through a magnetic or electrostatic field will follow a curved path. In a magnetic field the curvature of the path will be indicative of the momentum-to-charge ratio of the ion. In an electrostatic field, the curvature of the path will be indicative of the energy-to-charge ratio of the ion. If magnetic and electrostatic analyzers are used consecutively, then both the momentum-to-charge and energy-to-charge ratios of the ions will be known and the mass of the ion will thereby be determined. Other mass analyzers are the quadrupole (Q), the ion cyclotron resonance (ICR), the time-of-flight (TOF), and the quadrupole ion trap analyzers.
Before mass analysis can begin, however, gas phase ions must be formed from sample material. If the sample material is sufficiently volatile, ions may be formed by electron impact (EI) or chemical ionization (CI) of the gas phase sample molecules. For solid samples (e.g. semiconductors, or crystallized materials), ions can be formed by desorption and ionization of sample molecules by bombardment with high energy particles. Secondary ion mass spectrometry (SIMS), for example, uses keV ions to desorb and ionize sample material. In the SIMS process a large amount of energy is deposited in the analyte molecules. As a result, fragile molecules will be fragmented. This fragmentation is undesirable in that information regarding the original composition of the sample—e.g., the molecular weight of sample molecules—will be lost.
For more labile, fragile molecules, other ionization methods now exist. The plasma desorption (PD) technique was introduced by Macfarlane et al. in 1974 (Macfarlane, R. D.; Skowronski, R. P.; Torgerson, D. F., Biochem. Biophys. Res Commun. 60 (1974) 616). Macfarlane et al. discovered that the impact of high energy (MeV) ions on a surface, like SIMS would cause desorption and ionization of small analyte molecules, however, unlike SIMS, the PD process results also in the desorption of larger, more labile species—e.g., insulin and other protein molecules.
Lasers have been used in a similar manner to induce desorption of biological or other labile molecules. See, for example, Van Breeman, R. B.: Snow, M.: Cotter, R. J., Int. J. Mass Spectrom. Ion Phys. 49 (1983) 35; Tabet, J. C.; Cotter, R. J., Anal. Chem. 56 (1984) 1662; or Olthoff, J. K.; Lys, I.: Demirev, P.: Cotter, R. J., Anal. Instrument. 16 (1987) 93. Cotter et al. modified a CVC 2000 time-of-flight mass spectrometer for infrared laser desorption of involatile biomolecules, using a Tachisto (Needham, Mass.) model 215G pulsed carbon dioxide laser. The plasma or laser desorption and ionization of labile molecules relies on the deposition of little or no energy in the analyte molecules of interest. The use of lasers to desorb and ionize labile molecules intact was enhanced by the introduction of matrix assisted laser desorption ionization (MALDI) (Tanaka, K.; Waki, H.; Ido, Y.; Akita, S.; Yoshida, Y.; Yoshica, T., Rapid Commun. Mass Spectrom. 2 (1988) 151 and Karas, M.; Hillenkamp, F., Anal. Chem. 60 (1988) 2299). In the MALDI process, an analyte is dissolved in a solid, organic matrix. Laser light of a wavelength that is absorbed by the solid matrix but not by the analyte is used to excite the sample. Thus, the matrix is excited directly by the laser, and the excited matrix sublimes into the gas phase carrying with it the analyte molecules. The analyte molecules are then ionized by proton, electron, or cation transfer from the matrix molecules to the analyte molecules. This process, MALDI, is typically used in conjunction with time-of-flight mass spectrometry (TOFMS) and can be used to measure the molecular weights of proteins in excess of 100,000 daltons.
Atmospheric pressure ionization (API) includes a number of methods. Typically, analyte ions are produced from liquid solution at atmospheric pressure. One of the more widely used methods, known as electrospray ionization (ESI), was first suggested by Dole et al. (M. Dole, L. L. Mack, R. L. Hines, R. C. Mobley, L. D. Ferguson, M. B. Alice, J. Chem. Phys. 49, 2240, 1968). In the electrospray technique, analyte is dissolved in a liquid solution and sprayed from a needle. The spray is induced by the application of a potential difference between the needle and a counter electrode. The spray results in the formation of fine, charged droplets of solution containing analyte molecules. In the gas phase, the solvent evaporates leaving behind charged, gas phase, analyte ions. Very large ions can be formed in this way. Ions as large as 1 MDa have been detected by ESI in conjunction with mass spectrometry (ESMS).
ESMS was introduced by Yamashita and Fenn (M. Yamashita and J. B. Fenn, J. Phys. Chem. 88, 4671, 1984). To establish this combination of ESI and MS, ions had to be formed at atmospheric pressure, and then introduced into the vacuum system of a mass analyzer via a differentially pumped interface. The combination of ESI and MS afforded scientists the opportunity to mass analyze a wide range of samples. ESMS is now widely used primarily in the analysis of biomolecules (e.g. proteins) and complex organic molecules.
In the intervening years a number of means and methods useful to ESMS and API-MS have been developed. Specifically, much work has focused on sprayers and ionization chambers. In addition to the original electrospray technique, pneumatic assisted electrospray, dual electrospray, and nano electrospray are now also widely available. Pneumatic assisted electrospray (A. P. Bruins, T. R. Covey, and J. D. Henion, Anal. Chem. 59, 2642, 1987) uses nebulizing gas flowing past the tip of the spray needle to assist in the formation of droplets. The nebulization gas assists in the formation of the spray and thereby makes the operation of the ESI easier. Nano electrospray (M. S. Wilm, M. Mann, Int. J. Mass Spectrom. Ion Processes 136, 167, 1994) employs a much smaller diameter needle than the original electrospray. As a result the flow rate of sample to the tip is lower and the droplets in the spray are finer. However, the ion signal provided by nano electrospray in conjunction with MS is essentially the same as with the original electrospray. Nano electrospray is therefore much more sensitive with respect to the amount of material necessary to perform a given analysis.
Furthermore, High performance liquid chromatography ("HPLC") in combination with mass spectrometry has become an important tool in the analysis of a wide range of chemical and biological samples. When using conventional HPLC the time typically required for the elution of a given sample component (i.e., the time from when it starts to come out of the column to when it finished coming out of the column) is typically a few seconds. However, the time required to mass analyze a compound is much shorter (0.1 seconds or less). When using TOF mass analysis, the time needed to produce a mass spectrum may be as little as 0.01 seconds. As a result, one may, in principle, analyze the effluent from a number of columns simultaneously.
For example, FIG. 1 depicts a method and apparatus for multiplexing four spray needles 12, 14, 16 & 18 in an electrospray ionization source according to Kassel et al. U.S. Pat. No. 6,066,848 ("Kassel"). As described in Kassel, effluent from four HPLC columns 2, 4, 6 & 8 is injected into spray needles 12, 14, 16 & 18. The electrospray and subsequent ions produced by sprayers 12, 14, 16 & 18 are accelerated towards plate 36 by a potential between spray needles 12, 14, 16 & 18 and plate 36 and plate 38. Plate 36 includes aperture 32 located in an off-center position. During use plate 36 is rotated about its center (as indicated by arrows 34) and aperture 32 is aligned sequentially with spray needle 12, spray needle 16, spray needle 18, and spray needle 14, in turn. Ions produced by the sprayer aligned with aperture 32 pass through aperture 32 and on to orifice 20. These ions pass through orifice 20 and into mass spectrometer 10. In mass spectrometer 10, the ions are analyzed to determine their mass and abundance. As disk 36 is rotated, ions from the different sprayers (and the different HPLC columns) are sampled and mass spectra are produced—one mass spectrum for each spray needle 12, 14, 16 & 18 per each rotation of disk 36. The mass spectra may then be labeled electronically so as to associate the mass spectra with the sprayer (and HPLC column) from which they originate.
As described in Kassel, plate 36 serves as a "blocking" device, which moves in order to block the sample spray from all but one of spray needles 12, 14, 16 & 18 at any given time. Such a method and apparatus for multiplexing sample sprays has disadvantages. First, sampling orifice 20 is maintained in a fixed position with respect to spray needles 12, 14, 16 & 18. In such an arrangement, optimum conditions cannot be satisfied for each individual sprayer position with respect to the sampling orifice. Rather, an optimum geometry between sampling orifice 20 and all sprayers as a whole is optimized. Second, because plate 36 merely serves as a "blocking" device, significant portions of the sample spray is wasted (or lost) during each analysis (i.e., any sample spray that is blocked by plate 36 and does not pass through aperture 32).
Other techniques to sample ions from multiple ion sprayers are also known. One such method, similar to Kassel, as shown in FIG. 2, is an eight-way multiplexed electrospray inlet as disclosed by Robert Bateman et al., "Multiple LC/MS: Parallel and Simultaneous Analyses of Liquid Streams by LC/TOF Mass Spectrometry Using a Novel Eight-Way Interface", American Society for Mass Spectrometry, 1998 ("Bateman"). Bateman discloses sampling cone 66 surrounded by rotating cylinder 68 (e.g., in a manner shown by arrow 74) having apertures 64 & 65 and sprayers 42, 44, 46, 48, 50, 52, 54 and 56 evenly spaced in an arc around cylinder 68. When sprayed, the sample droplets travel through aperture 64 or 65 (i.e., depending on which aperture is positioned in front of the spraying sprayer) to sampling cone 66, which is at the center of cylinder 68. Unlike Kassel (FIG. 1), rather than using a blocking plate (or disk), Bateman teaches a rotating cylinder 68 having apertures (64 & 65) for allowing the sample spray to pass therethrough and into sampling cone 66. Sampling cone 66 then transfers ions from atmospheric pressure region of source block 40 into a vacuum system of mass spectrometer 70, as indicated by arrow 72. Again, as disclosed in Kassel, the method and apparatus disclosed by Bateman uses a "blocking" device to prevent unwanted sample from entering the mass analyzer at a given point in time.
Also, methods for sampling solutions from different sprayers without using a multiplexing technique are known. For example, FIG. 3 depicts a multi-ESI-sprayer, multi-nozzle time-of-flight mass spectrometer as disclosed in Longfei Jiang and Mehdi Moini, "Development of Multi-ESI-Sprayer, Multi-Atmospheric-Pressure-inlet Mass Spectrometry and Its Application to Accurate Mass Measurement Using Time-of-Flight Mass Spectrometry", Anal. Chem. 72,20 (2000) ("Jiang"). An elevated pressure ion source always has an ion production region (wherein ions are produced) and an ion transfer region (wherein ions are transferred through differential pumping stages and into the mass analyzer). Typically, the ion production region is at an elevated pressure—most often atmospheric pressure—with respect to the analyzer. Disclosed in Jiang is the use of a multitude of sprayers 14 with two differential pumping stages 90 & 96. Ions from different solutions (e.g., ESI samples such as reference compound 76, CE sample 78 and LC samples 80 & 82) are transferred from atmospheric pressure to a first differential pumping region 90 by gas flow via quadruple nozzle 84. Quadruple nozzle 84 comprises multiple sprayers at its exit end to eject ions from the different solutions in paths 86, 88, 92 & 94 aimed at an aperture in pressure restriction 98 (e.g., a skimmer), which transfers the ions from first pumping region 90 to second pumping region 96. An electric field applied across the exit end of quadruple nozzle 84 and restriction 98 as well as gas flow assist in the transfer of ions between these regions. Second differential pumping region 96 includes multipole 101 (comprising rods 102, 104, 106 & 108) which accepts ions of a selected mass/charge (m/z) ratio and guides them through second pressure restriction 100 and into TOF mass spectrometer 110.
Turning next to FIG. 4, shown is a prior art multiple needle electrospray apparatus for a mass spectrometer according to PCT Application No. PCT/CA99/00264 by applicant Synsorb Biotech, Inc., entitled "Electrospray Device For Mass Spectrometer" ("Synsorb"). As depicted, Synsorb's multiple needle electrospray apparatus includes a plurality of electrospray needles 120 mounted on a rotatable plate 112 for sequential injection of multiple sample streams. The rotatable electrospray apparatus allows collection of data from multiple sample streams by a single mass spectrometer 128 in a short time by rotating the electrospray apparatus to sequentially monitor the stream from each of the needles 120 for a brief duration before rotating the plate 112 to another of the needles.
According to one method for screening compound libraries which involve analysis of multiple sample streams by electrospray mass spectrometry, a compound library is prepared, such as by combinatorial chemistry techniques. Multiple sample streams each of which contain a compound library or sub-library are passed through a plurality of frontal chromatography columns. Each stream is passed through a single column to analyze the interaction of members of that sample stream with a target receptor within the column. The columns include a solid support or inert material on which the target receptor is bound or coupled. As the sample stream is continuously infused through the chromatography column. those compounds within the sample stream having a higher affinity for the target receptor (i.e., lipands) will be more strongly bound to the target receptors. When a compound has reached equilibrium with the column. it will break through and begin to pass out of the column with those compounds having the lowest affinity passing out of the column first. The sample streams exiting the chromatography columns are analyzed by electrospray mass spectrometry to determine the break through time for each compound. Mass spectrometry is particularly useful for this process because it allows for both detection and identification of the library members present in the sample streams exiting the columns.
FIG. 4 illustrates a prior art electrospray device for delivery of multiple liquid sample streams to a mass spectrometer according to Synsorb. The electrospray device includes electrospray chamber 114 for charging the droplets of a sample stream delivered by electrospray needles 120 and delivering the charged ions in a beam to mass spectrometer 128.
Electrospray needles 120 each have an upper end mounted on rotatable plate 112 in the circular arrangement. The lower ends of the electrospray needles may be rotated into a reproducible delivery position within electrospray chamber 114. The delivery position is at a precise location with respect to orifice 122 of mass spectrometer 128 which allows the sprayed droplets to be focused into a beam passing through orifice 122. The delivery position is within about ±0.5 mm of an ideal position in fluid connection with each of the electrospray needles 120 is a sample source such as chromatography columns 118 illustrated in FIG. 1. The chromatography columns 118 are mounted on the top of the rotatable plate 112 or are connected to the needles 120 with flexible lines.
Electrospray chamber 114 surrounds orifice 122 of the mass spectrometer and is open to atmospheric pressure, while surrounding needles 120 for containment purposes. Only needle 120 placed closest to a delivery position experiences a sufficiently high electric field and proximity for the efficient transmission of gas phase ions into the mass spectrometer 128. Further, electrospray needles 120 are coaxial needles which deliver the sample stream through an inner needle lumen and deliver a nebulizer gas, such as nitrogen, coaxially around the sample stream to break up the flow of the sample stream into a spray of droplets. Alternatively, the needles 120 may be single lumen needles delivering only the sample stream. The electrospray chamber 114 includes a charged sampling plate 116 surrounding the mass spectrometer entry orifice 122. The electrospray chamber 114 can also include an electrode 126 in the form of a half cylindrical member. The charged sampling plate 116 and half cylindrical electrode 126 are charged with an electric potential preferably of about 0 to 6000 volts. The electric field established by the sampling plate 116 and the electrode 126 surrounds the grounded needle 120 and imparts a charge to the sprayed droplets.
Alternatively, the charging of the sample stream droplets exiting electrospray needle 120 may be accomplished by use of a charged electrospray needle, biased sampling plate 116, and no electrode 126. The needle 120 may be continuously charged or may be charged only when the needle reaches the delivery position within electrospray chamber 114 by an electrical contact.
A counter current drying gas. such as nitrogen, is delivered to the electrospray chamber 14 through passageway 124 between charged sampling plate 116 and entry orifice 122 to assist in desolvating or evaporating the solvent from the sample stream to create fine droplets. Optionally, the drying gas may be delivered to electrospray chamber 114 in manners other than through passageway 124. In addition, the nebulizer gas may be delivered to the electrospray chamber 114 separately rather than by a co-axial flow through the electrospray needle. Both the nebulizer gas and the drying gas are introduced into the electrospray chamber 14 to obtain fine droplets of the sample stream. However, depending on the flow rate of the sample stream, the fine droplet size may be achieved without the need for a nebulizer gas and/or a drying gas.
The rotatable plate 112 is rotated by a motor connected to a drive shaft. The motor is interfaced with a controller to control the rotation of the plate and the dwell times for each of the needles.
During operation, multiple sample streams are continuously delivered to each of the chromatography columns 118 from sample sources by, for example, a pump, such as a syringe pump. The sample streams exiting columns 118 may be combined with a diluent in a mixing chamber or mixing tee 138 positioned between the column and needle 120. The sample streams pass continuously through electrospray needles 120 with a nebulizer gas delivered around the sample streams to break up the flow into droplets. In one disclosed embodiment, sample streams pass through all of the needles 120 simultaneously with only one of the streams from a needle positioned at the delivery position being analyzed by the mass spectrometer at a time. The sample streams from the remaining needles 120 are optionally collected by a tray 130 for delivery to waste.
To perform analysis of the multiple sample streams, Synsorb provides that rotatable plate 112 is stepped in one direction (e.g., counter clockwise), through approximately half of the needles 120. When a quadrupole mass spectrometer is used, a dwell time for each electrospray needle 120 ranges from about 0.5 to 10 seconds, preferably about 1 to 5 seconds before switching to the next column. After analysis of approximately half the sample streams, the rotatable plate 112 then returns clockwise to a home position and begins stepping in an opposite direction (e.g., clockwise), through the remaining half of needles 120. Finally, rotatable plate 112 returns again to the home position and repeats the procedure. The system operates continuously for a preset period of time related to the chromatographic requirements. Step times for rotation between successive needles is preferably less than about 100 msec, more preferably less than about 10 msec. The rotation of plate 112 in one direction followed by reversing the rotation is preferred to prevent the feed lines for feeding the sample streams from the pump to columns 118 from becoming twisted.
Alternatively, the sample source, the pump or alternative, and the feed lines for delivery of the sample streams to columns 118 may be mounted on plate 112. With this embodiment, plate 112 may be rotated continuously in one direction to sequentially analyze the flows from each of the needles without requiring the plate to reverse direction and return to a home position.
This multiple needle electrospray apparatus is described for use with any of the known mass spectrometers including a quadrupole mass spectrometer, quadrupole ion trap mass spectrometer, Penning or Paul ion trap mass spectrometer, FTICR (Fourier transform inductively coupled resonance) mass spectrometer, TOF mass spectrometer, and the like. A TOF mass spectrometer is preferred due to its high spectral acquisition rate (>100 spectra per second). However, the slower quadrupole mass spectrometer may also be used which can record spectra at a rate of approximately 0.5 to 1 per second. The dwell times for analysis of each sample stream will vary depending on the spectral acquisition of the mass spectrometer used.
Synsorb also discloses the use of different numbers of electrospray needles depending on the number of sample streams which are to be analyzed. The spacing of the multiple electrospray needles 120 is important to the operation of the electrospray device. In particular, electrospray needles 120 should be spaced sufficiently to prevent cross over effects resulting from the sample stream from one columns influencing the analysis of the sample stream of an adjacent column. In addition, electrospray needles 120 should be spaced as close together as possible to minimize the step times for rotation between adjacent needles. Preferably, the spacing between columns should be about 0.5 cm to 10 cm, depending on the mass spectrometer used. Alternatively, physical blocking members may be used to prevent cross over effects and allow closer needle placement.
Next, FIG. 5 shows a top view of another rotatable electrospray apparatus for delivery of sample streams to a mass spectrometer 140 according to Synsorb. The electrospray apparatus includes a plurality of electrospray needles 142 mounted in a radial arrangement on a rotatable plate 144. Each of the needles 142 are in fluid connection with a chromatography column 146. The radial arrangement of the electrospray needles 142 allows more columns 146 to be positioned on a rotatable plate 144 of a smaller diameter. According to this embodiment, the discharge ends of the needles 142 are preferably spaced a distance sufficient to prevent a cross over effect between adjacent needles. However, the columns 146 can be arranged close together around the periphery of the rotatable plate 144.
The present invention is distinguished from prior art by providing two distinct advantages. First, the preferred embodiment allows the use of heated drying gas and an endcap for efficient drying of sprayed droplets. Second, the sampling orifice of the multiple part capillary is, in the preferred embodiment, moved to an optimum position for the sampling of ions from a given sprayer, while in prior art designs, the sampling orifice was in a fixed position (not necessarily the optimum for any given sprayer). A result of this configuration (i.e., having a movable "sampling orifice") is that the sampling orifice may be positioned closer to the sprayer, allowing use of a wider variety of spray devices, such as nanosprayers, microsprayers, which cannot be used with the prior art multiplexing devices.
The present invention further distinguishes itself from prior art by providing a means and method for simpler, more efficient, multiplexed sample introduction into an ESI mass spectrometer. According to prior art multiplexing apparatuses and methods, first, a sample spray is formed from the plurality of sprayers. Second, the device selects the specific sprayer from which to accept the sample spray. Third, the droplets from the sample spray are desolvated in an electric field wherein sample ions are formed. Fourth, the sample ions are transported into a mass spectrometer. This sequence of spraying, selecting, desolvating, and then transporting the sample ions has significant limitations and disadvantages. For example, the prior art multiplexing devices cannot be used adequately with nano- or micro-electrospray sources because the sampling orifice cannot be brought close enough to the sprayer(s). Also, the prior art cannot utilize different types of sprayers (i.e., electrospray, pneumatic spray, etc.) simultaneously. That is, electrospray (specifically, nanospray) cannot be used with drying gas while drying gas is needed for pneumatic sprayers. The prior art multiplexing designs do not function such that drying gas may be used with only some of the plurality of sprayers—it must be used with all or none. Further, in the prior art multiplexing devices, optimum conditions for maximum performance cannot be obtained for each sprayer independently—only a compromised arrangement may be obtained.
In contradistinction, the present invention uses a multiple section capillary device, which allows the orifice of the entrance to a mass analyzer to be moved (e.g., rotated) so as to sequentially sample ions from a series of ESI sprayers. The use of such an apparatus to multiplex samples from a plurality of sprayers necessarily provides a distinct and improved method of such sampling. Some of the distinct advantages provided by the present invention include use with nano- or micro-electrospray sources since the sampling orifice may be positioned at any distance from the sprayer(s) desired, the ability to simultaneously utilize any number of different types of sprayers (i.e., electrospray, pneumatic spray, etc.), and the ability to optimize the conditions for maximum performance and resolution for each sprayer, independently—a significant improvement over the prior art devices. Also, optionally, the use of an endcap electrode and drying gas in conjunction with a multiplexed sampling apparatus may be used to enhance the performance of an ESI/HPLC source for a mass spectrometer.

Means and method for multiplexing sprays in an electrospray ionization source


The current in a conductor is measured by exploiting the Faraday effect in a sensing fiber. The light returning from the sensing fiber is split into at least two parts, at least one of which is analyzed by a first circular analyzer for generating a first signal. A second part may e.g. be analyzed by a second circular analyzer, and a third part may be analyzed by a linear analyzer. By combining the signals obtained in this way, the current induced phase delay in the returning light can be measured efficiently and accurately.

The measurement of currents using light waves in an optical fiber wound around a conductor has e.g. been described in EP 856 737.
In this device, two orthogonal, linearly polarized light waves are sent through an electro-optic phase modulator for introducing an ac phase modulation and then over a polarization maintaining fiber (PMF) to a site of measurement, where they are converted by a retarder to two circularly polarized light waves of opposite orientation. These circularly polarized light waves pass through a measuring fiber wound around a conductor. At the end of the measuring fiber, a reflector sends the light waves back to the retarder, where they are converted back to two linearly polarized light waves. The returning light from the retarder is separated from the original light in a beam splitter and sent to a detector.
Alternatively, devices based on fiber gyro modules can be used.

Fiber-optic current sensor with polarimetric detection scheme


The content items presented to a user account as part of a media station can be recorded in a content history index, which can be requested and presented to the user account. The content history can enable a user to revisit the content items included in the content history and/or provide feedback regarding the content items. The version of the content item returned to the user can be based on the client device used to request the content item. For example, a user that was presented a content item on their mobile device, can later request to revisit the content item on their PC and receive a version of the content item best suited for presentation by the PC, rather than the version presented on the mobile device.

Invitational content items such as advertisements have commonly been presented alongside traditional media, such as television and radio. Due to the nature of traditional media, the advertisements presented have not provided an interactive experience in which a user can engage with the advertisement to select further information or to make an immediate purchase.
The internet, in contrast, allows for media rich interactive advertisements that allow a user to request further information, access secondary information, etc. While these advertisements provide much greater functionality, a user is not always in an appropriate setting to interact with the advertisement to fully appreciate everything that is offered. For example, a user streaming a media stream while driving may not be able to interact with their mobile device to properly engage with the advertisement. Likewise, a user on a mobile device with a smaller display may wish to interact with the advertisement when using their desktop, laptop or tablet Personal Computer (PC) that provides a much larger display.
Currently, a user has no way of re-accessing an advertisement that was presented to the user. For example, a user unable to interact with an advertisement presented while driving cannot access the advertisement at a more convenient to engage with the advertisement. As a result, users miss out on information that they are interested in and advertisers get less value from their marketing efforts.


A chair for an aerial transport installation comprises a pivoting protective cover actuated by an operating mechanism with automatic latching of the cover in the closed position. An operating lever is pivotally mounted on a first pivoting spindle of the cover and operates in conjunction with a latch actuated by a cable transmission device between a latched position and an unlatched position. The latch comprises a first arm equipped with a latching nose and a second arm designed to come up against a first stop corresponding to the latched position or a second stop corresponding to the unlatched position. The latching zone is situated at the base of the shell, preferably in a gap situated between the first spindle and the second spindle.

The invention relates to a chair for an aerial transport installation, in particular a chair-lift, comprising:                a support bow connected to a hanger arm,        a pivoting cover for protection against inclement weather, which cover is formed by a shell made of transparent plastic material mounted swivelling around a first spindle of the bow between a raised open position and a lowered closed position,        and an operating mechanism with automatic latching of the cover in said lowered closed position, said mechanism comprising an operating lever associated by a transmission device to an operating means controlled by actuating means provided in the terminal.

Operating mechanism with latching of a pivoting cover for a chair-lift


A system and method for determining telephone status over a network. The system and method provides for off hook status to be determined by a switch or other monitor that then provides that information to a telephone status file. The telephone status file is accessible over the Internet by computer so that a calling party can first determine if the called party is on the telephone. Thus wasted time in making calls that cannot be completed is avoided. The system operates over normal PSTN's, over cable systems, and over the Internet.

This invention relates generally to electronically determining the status of a telephone over a network. More specifically, the present invention provides a method and apparatus for obtaining the status of a telephone (whether on-hook or off-hook) over a network in order to maximize the probability of reaching a desired party. It also provides a method and apparatus for sending an e-mail to the desired party for storage as a voice mail message.
Literally millions of times per day, parties attempt to contact one another, only to find that the party initiating the telephone call receives a busy signal or is put into the phone mail of the receiving telephone when that telephone is off-hook. Not only is this experience frustrating for the caller, but also can result in lost business or social opportunities on the part of the receiving party who is on the line speaking with someone else. In addition, receiving busy signals and the inability to complete telephone calls results in the loss of millions of dollars in revenue both from the time expended by the caller in trying to reach the desired party, as well as lost opportunities for commerce or other social contact.
Telephone line activity monitoring has been the subject of invention in the past. A form of line activity monitoring has been proposed for the purpose of obtaining information regarding statistics of line usage. This proposed system detects the usage of the line, but does not transmit status information to others in any current fashion. For further details, refer to U.S. Pat. No. 4,559,416 to Theis et al.
Another monitoring system has been described whose purpose is to notify an operator that a telephone line is open so that a desired message can be delivered by the operator to a receiving party. This system comprises an automatic dialer that attempts to reach individuals on a repetitive basis until a connection is made. Again, status of the telephone at any given point of time is not provided. For further details, refer to U.S. Pat. No. 3,989,899 to Norwich.
An integrated calling directory has been described that utilizes a personal computer that stores information about the numbers being called. It does not address the problem associated with the called party telephone being in an off-hook condition. This condition is not reported in any fashion to the initiator of the telephone call. For further details, refer to U.S. Pat. No. 4,734,931 to Bourg et al.
A communication system has been proposed that uses a voice message system for storing and retrieving voice messages and faxed data and for converting text into voice messages. This proposed system does not deal with the issue of how to contact the party receiving the phone call but only leaves a message for that party in the event that the phone is in an off-hook condition. For further details, refer to U.S. Pat. No. 5,530,740 to Irribarren et al.
Another information processing system has been described as having a telephone and an informational processing device. This system does not address the issue of whether a called party telephone is in an on-hook or off-hook condition. For further details, refer to U.S. Pat. No. 5,500,893 to Onosaka.
A system for synchronization of mail boxes over a network has been proposed. This system is designed to ensure that information in electronic mail is complete in a series of different mailboxes. The issue of providing information to a caller regarding the status of a called party's telephone is not dealt with. For further details, refer to U.S. Pat. No. 5,647,002 to Brunson.
What is desired is a system whereby a calling party can pre-determine the status of a called party's telephone (on-hook or off-hook) so as to maximize the opportunity for completing a telephone call to the desired party.

Method and apparatus for obtaining telephone status over a network


A liquid crystal display (LCD) that may include: a plurality of transistors groups forming a pixel array of said LCD, wherein the transistors groups are independently controllable; a plurality of backlight units, forming a backlight surface of said LCD, wherein the backlight units are independently controllable; a data refresh module configured to periodically refresh data at said groups of transistors, at a specified order, over a refresh cycle time; and a backlight control module configured to periodically dim the backlight units at said specified order over a backlight cycle time which is substantially shorter than the refresh cycle time.

Typically, a liquid crystal display (LCD) includes a backlight surface that is configured to produce the backlight that passes through the pixel array which is usually comprised of transistors such as thin film transistors (TFT) and the like. While most LCDs utilize backlight modules that are always being uniformly lit as a single unit, some backlight units are known to be partially lit or locally dimmed, usually based on the data being inputted to the pixels array.
One motivation for local dimming is a case in which a specified region of the display is required to present a very dark (or black) scene, ambiance, or object. By dimming specific backlight units, better representation of the very dark data is achieved. One characteristic of the aforementioned solution is that it is clearly data-aware and the local dimming is carried out based on values of data applied to the pixels upon refreshing.
One known artifact in LCDs is that a backlight which illuminates beyond a specified intensity might photo activate pixel transistors as they as being refreshed. The photo activation may lead to transistors saturation and undesirable results affecting the quality of the image presented.

Liquid crystal display having a rolling backlight


The exercise device of the present invention includes an elongated rigid bar having a handle disposed at one end and a joint projection disposed at the opposite end. The joint projection is pivotably received by the joint collar of an exercise attachment. In an alternate embodiment, a second joint projection is provided at the opposite end of the exercise device to pivotably receive a second exercise attachment. The pivoting connection between the exercise attachments and the rod mimics normal biomechanical movement to decrease the chance of injury or re-injury to the user. The exercise device is telescopically extendable to selectively change its usable length.

1. Field of the Invention
The present invention relates to exercise and rehabilitation devices, and more particularly to a telescopically adjustable exercise device that pivotably removably receives one or more exercise attachments for the manual exercise of an individual's upper extremities.
2. Description of the Prior Art
An injury to an individual's upper extremity, which may include the individual's shoulder, arm, elbow, wrist and/or the supportive tissue between the joints, typically requires some form of rehabilitation. Such rehabilitation generally involves the reestablishment of several physical aspects of the involved upper extremity. For example, depending on the particular injury sustained, an individual's range of motion is often significantly reduced after an upper extremity injury. Varying magnitudes of neuromotor inhibition and muscle atrophy are also experienced as a result of such injuries. Accordingly, the appropriate level of kinetic neuromotor control must be reestablished. The patient may also experience a measured loss in kinesthetic awareness, which must be reestablished in order to minimize the level of altered limb coordination and reaction time experienced by the patient. It is also important to reestablish the patient's functional activity so that they are able to return to a desired pre-morbid activity level without an unreasonable risk of re-injury or further degeneration. Ultimately, the patient is rehabilitated through the stages of healing beginning with the inflammatory stage, progressing through the proliferation stage, and completing the rehabilitation with the remodeling stage.
When reestablishing a patient's range of motion, it is important to initially limit the patient's muscle activity in the injured upper extremity. The introduction of passive range of motion at this stage of rehabilitation limits the risk of re-injury or irritation to the upper extremity. This is typically achieved through the passive movement of the injured arm by an external force such as an automated machine, a physical therapist, or the patient's unaffected arm. Those methods that allow the patient to self-articulate the injured upper extremity allow for a greater flexibility in the patient's rehabilitation program. Without the requirement of expensive machinery or a physical therapist, the patient is able to work on the exercises in the comfort of the patient's home at a time convenient for the patient.
One prior art method for allowing the patient to self-articulate the injured upper extremity typically involves the use of a broom handle. Using this method, the patient grasps opposite ends of the broom handle with both hands. The patient then uses his healthy arm and shoulder to move the broom handle reciprocally in vertical, horizontal or diagonal directions. These motions cause the patient's injured arm to move responsively through the upper extremities' available range of motion. This prior art method suffers from two serious problems. First, the rigid nature of the broom handle tends to force the injured arm in particular directions, irrespective of the natural range of motion provided by the joints and accompanying soft tissue. Forcing the injured upper extremity to travel in unnatural or undesired ranges of motion typically causes the patient to re-injure the upper extremity rather than rehabilitate it. Aside from its inability to mimic normal biomechanics, the broom handle method is also problematic in that it requires the active use of the muscles of the injured upper extremity to grip the broom handle, which works against the definition of passive range of motion.
An example of a prior art device that was developed in an effort to address the problems encountered when a patient uses an exercise device such as a broom handle is disclosed in U.S. Pat. No. 4,395,039. The device itself is comprised of an elongated bar having opposite ends. One end is adapted to be gripped by the patient's healthy arm. The opposite end of the bar is attached to one end of an elastic cord that has a gripping handle disposed at the opposite end. In use, the patient grips the gripping handle with his injured arm. The patient then uses his healthy arm to articulate the exercise bar in a manner similar to that using the broom handle. The device improves upon the broom handle method by providing some passive range of motion that is not as rigidly dictated by the exercise bar as a patient will experience with the broom handle. However, this device can achieve a range of motion in the injured upper extremity that is too independent of the movement of the exercise bar. Due to the flexible nature of the elastic cord, the device lacks an element of precision when directing the injured upper extremity through a desired range of motion. Moreover, this device, much like the broom handle, must be actively gripped by the patient's injured arm. Again, this is inconsistent with the goals of passive range of motion exercises.
The next stage of the rehabilitation process is the reestablishment of kinetic neuromotor control at specific sequences throughout the injured upper extremities' range of motion. This goal can be attained through graded isotonic muscle activity of synergistic-specific muscles or muscle groups within the injured upper extremity while providing a measured level of graded force from the healthy upper extremity. None of the prior art exercise devices can provide this necessary element while simultaneously allowing multi-plane joint-independent range of motion without the necessity of active motor work at the distal end of the injured upper extremity.
In the next stage of rehabilitation, the patient engages in restrictive range of motion exercises to regain the strength necessary to achieve an active range of motion in the injured extremity, independent of any external assistance. In order to safely transition a patient to functional active ranges of motion independent of assistance, it is preferred that the exercise device used by the patient support both open kinetic chain and closed kinetic chain exercises. Moreover, an exercise tool used in this stage of rehabilitation should support agonist, antagonist, isometric and isotonic muscle activity through graded forces applied through both the injured and healthy upper extremities. None of the prior art exercise devices are capable of such a flexible utility. Accordingly, multiple exercise tools must be used in an attempt to safely attain an active range of motion.
Accordingly, what is needed is a single exercise device that supports the rehabilitation of an injured extremity through normal biomechanics. More importantly, the exercise should safely benefit the patient's rehabilitation from the passive range of motion stage through the achievement of active independent ranges of motion by the injured upper extremity.


The present invention provides a spread type processed food using foie gras (duck liver, goose liver) and chicken breasts, a composition thereof and a method for manufacturing the same, and more particularly, a spread type processed food using foie gras and chicken breasts, which is manufactured using foie gras and chicken breasts in a spread form such as butter or jam that can be simply spread on a preferred food such as bread and easily eaten, wherein fishy smell and peculiar smell (odor) of foie gras are effectively removed to allow people of all ages and both sexes to easily eat without repulsion, and the processed food is rich in protein and contains diverse vitamins to promote brain development of growing children and protect various diseases, thereby planning promotion of public health, as well as a composition thereof and a method for manufacturing the same.

Typically, foie gras is a French term referring to a duck or goose liver and known as one of the world's three major delicacies. Diverse dishes and processed foods containing the foie gras as a main raw material have been introduced in Europe including France because of butter-like soft taste and excellent flavor.
Generally, the duck liver is mostly used as the foie gras in terms of price. The duck liver contains amino acids and abundant protein acting as a catalyst material for various chemical reactions in cells, thereby planning health promotion, and contains vitamin A, E, etc. for enhancing resistance to diseases, as well as reducing a harmful LDL cholesterol level while raising a beneficial HDL cholesterol level, and thereby preventing cardiovascular disease. Further, the duck liver contains a large amount of iron and manganese, such that deficiency anemia may be prevented while reducing a degradation in the resistance to disease, fatigue, and headaches, etc., and calcium and manganese necessary for the growing children may also be provided to strengthen bone, thereby enabling formation of a stable bone structure.
As such, a variety of recipes for haute cuisine including foie gras has been developed due to potency and flavor thereof, and foie gras itself has renown as one of the three dishes around the world along with caviar and truffles. However, despite of various developed recipes, the foie gras has a limitation in applying to diverse processed foods as favorite foods for children as well as general dishes because it is difficult to effectively remove the fishy smell and peculiar smell of the duck liver.
Accordingly, methods for removing peculiar smell or odor of the liver by adding spices thereto have been proposed in, for example, Korean Patent Laid-Open Publication No. 10-2009-0114804, Korean Patent Laid-Open Publication No. 10-2002-0053210, Korean Patent Registration No. 10-1334087 and the like. In particular, Korean Patent Registration No. 10-1334087 discloses a method for removing fishy smell or odor of a duck liver by introducing medical herbs, for example, Angelica gigas NAKAI, hawthorn and Maximowiczia chinensis, etc. into the duck liver, instead of such spices.
However, the methods proposed in Korean Patent Laid-Open Publication No. 10-2009-0114804, Korean Patent Laid-Open Publication No. 10-2002-0053210 and Korean Patent Registration No. 10-1334087 are all a simple method of mixing a loaf of duck liver with the medicinal herbs or spices in order to remove the fishy smell and odor, which involves a problem in which distinctive aroma of the spices and/or medicinal herbs may not deeply penetrate into the duck liver but only exist on an outer surface thereof after cooking.
For this reason, the processed foods produced by the conventional manufacturing methods have a problem in which the fishy smell and odor latent in the duck liver come out to cause displeasure and repulsion during chewing the same, thereby degrading food texture or mouthfeel, in particular, children and women very sensitive to the smell may be repulsed by the fishy smell and odor of such a liver, hence causing limits in applying foie gras to any processed food in a spread form such as butter or jam, which is spread on and eaten along with bread.

Foie gras using the liver of duck without force-feeding method, its composition and manufacturing method


An apparatus for facilitating avoidance of a vehicle collision with an object, comprises a vision sensor providing image data, and an image analyzer, operable to provide an estimated time to collision of the vehicle with the object. The estimated time to collision is determined from a rate of expansion of an image element corresponding to the object within the image data, and the apparatus provides a warning if the estimated time to collision is less than or approximately equal to a predetermined time.

Optical flow is a measure of image movement across a visual field. It is the apparent motion of image brightness patterns in a sequence of images. In an image each pixel corresponds to the value obtained by the projection of a three-dimensional image onto an image plane. When an object moves, the corresponding projection, or image element within the image data corresponding to object, changes position in the image plane. Optical flow is the vector field showing the direction and magnitude of such changes from one image to the other.
In conventional stereo vision based collision avoidance approaches, the actual distance to a remote object is calculated. However, such distance measurements may be difficult in changing environmental conditions. Hence, an improved collision warning system would not necessarily determine the actual distance to a remote object.


Disclosed is a method for manufacturing the polysilsesquioxane (PSSQ) within the carbon dioxide solvent through the control of the pressure and temperature within a reactor by the state changes, e.g., a liquid state or supercritical state, of carbon dioxide as a solvent which is environmentally friendly and pollution-free, that is to say, by making use of the fact that the solubility of reactant and product is changed according to the pressure and temperature in manufacturing the polysilsesquioxane (PSSQ).

While carbon dioxide (CO2) solvent is environmentally friendly and pollution-free, it has very much lower solvency than other polar solvents and has a problem in dissolving a polar compound or inactive compound. However, it has been known that a polymer of a kind of silicon like polydimethylsiloxane and a partially fluorinated compound have a good solubility for liquid carbon dioxide and supercritical carbon dioxide.
When the temperature and pressure are higher than those of a critical point, a state where densities of the two states become the same as each other and there is no distinction between the two states is referred to as a supercritical state, and is also called supercritical fluid (SCF) because the state has the characteristics of a fluid which is easy to transform unlike a solid body and freely flows.
The molecule in the supercritical state has a density close to that of liquid and a viscosity lower than that of liquid, and thus, it has properties close to gas. The molecule in the supercritical state is rapidly diffused to have high thermal conductivity, so that it can be usefully used in chemical reactions. The carbon dioxide has a low critical temperature (31.1° C.) and a low critical pressure (73.8 bar). Therefore, the carbon dioxide is able to easily reach the liquid state and the supercritical state. Also, due to the high compressibility of the carbon dioxide, the density or solvent strength of the carbon dioxide is easy to change according to the change of the pressure. The carbon dioxide is changed into gas carbon dioxide by reducing the pressure.
Also, the carbon dioxide is nonpoisonous, nonflammable, inexpensive and environmentally friendly. Under the condition of a temperature and a pressure higher than those of the critical condition (TC=31.1° C., PC=73.8 bar) of the carbon dioxide, the carbon dioxide becomes the supercritical state. The carbon dioxide in the supercritical state has unique properties different from those of the liquid or gas carbon dioxide. The supercritical carbon dioxide has a density similar to that of the liquid carbon dioxide, a viscosity as low as that of the gas carbon dioxide, and is rapidly diffused.
Meanwhile, a large number of organic or halogen solvent are annually used as a polymer polymerization solvent all over the world. All of the solvents being used are dangerous to health and safety, and are harmful to the environment. In particular, petroleum-based solvents are flammable and generate smog. When a non-volatile solvent such as an aqueous solution is used instead of the volatile solvent, wastewater is produced and there is a big disadvantage that a lot of time and energy is required for drying after cleaning.
Also, most functionalizations in the siloxane structure have been performed through POSS up to now. However, since the siloxane has a low molecular weight and has a relatively low glass transition temperature and melting point, the siloxane is not suitable for the application to the thin film within an electronic material such as OLED and organic solar cell, so that there is a problem in practicability.
As compared with an existing linear siloxane, a ladder type silicon polymer structurally secures the safety. Accordingly, the trapezoidal silicon polymer has a high thermal stability, and the use of the trapezoidal silicon polymer is expanding very rapidly due to high compatibility with the organic solvent. Also, since the improvement of characteristics of the polysilsesquioxane (PSSQ) results from a highly regular ladder-form structure, research has been variously devoted to both the development of a new starting material capable of easily forming the ladder-form structure and a method for condensing the new starting material.
Polyorganosilsesquioxane, a kind of the polyorganosilsesquioxane, is easily typically manufactured as follows. A precursor hydrolyzate is obtained by hydrolyzing trichlorosilane or rialkoxysilane, and the precursor hydrolyzate is dehydrocondensed under an alkali/acid catalyst, so that polymer having a low molecular weight (Mn is from about 20,000 to 30,000, and Mn/Mw is from about 3 to 5) can be easily manufactured.
First, a method for manufacturing the polyorganosilsesquioxane by using the trichlorosilane will be described as follows. In the hydrolysis of the trichlorosilane, oligomer (Mn is from 1,000 to 2,000, and PDI is from 2 to 5) produced by the condensation reaction performed simultaneously with the hydrolysis has a complex and various structures instead of silanetriol of a single structure, and when it becomes to have a high molecular weight by using this, it is easy to form a 3-dimensional network structure due to the structural defect (inter-hydroxy group) of the oligomer, which is caused by the existence of hydroxy group within the molecule, and any structure of its own. Therefore, the following disadvantages are caused. That is, 1) it is impossible to control the structure of the produced polymer 2) it is difficult to control the molecular weight of produced polymer and to obtain the polymer having a high molecular weight, therefore 3) the produced polymer loses high regularity, so that the solubility in the solvent is reduced 4) in particular, the low molecular weight residues have a bad influence on the thermal resistance and mechanical properties of the polymer.
Second, a prior method for manufacturing the polyorganosilsesquioxane by using the trialkoxysilane has also the advantage of being easier to handle, for example, hydrolysis rate control, than the trichlorosilane. However, due to both the molecular defect of the oligomer, which is caused by the existence of the hydroxyl group within the structure of the produced polymer, and the existence of alkoxy group, the following disadvantages are caused. That is, 1) the polymer having a branch-form instead of the ladder-form is produced 2) there are requirements for the selection and amount of the catalyst to be used, the selection of the reaction solvent, and a precise pH adjustment of the reaction solution, however, the adjustment is not easy 3) the method using the trialkoxysilane is not suitable for the manufacture of the highly regular silicon ladder-form polymer, for example, a micro gel is formed by forming a network structure which is 3-dimensional to some degree, and the like. Also, according to both various synthesis methods known up to now, for example, a sol-gel method, a ring opening polymerization method, an equilibrium polymerization method, etc., and what is known through the research on their structures, the condensation process is very complex and various and the structure of the polymer is not sufficiently controlled, so that products now being marketed does not comply with various conditions for being used as industrial new material. This problem acts as a certain limit to practicalization.
In the publication of Korean patent application No. 10-2009-0056901, disclosed is a polyalkylsilsesquioxane particle and a method for manufacturing the same. More specifically, the patent application provides a method for manufacturing the polyalkylsilsesquioxane through the first reaction in which, after an acid homogeneous aqueous solution is prepared by adding an acid catalyst to an aqueous medium, the hydrolysis is performed by adding alkyltrialkoxysilane to the aqueous solution, the second reaction in which a polycondensation is performed under an alkali catalyst, and the third reaction in which end-capping is performed by adding alkoxytrialkylsilane including triorganosilyl group, and provides the polyalkylsilsesquioxane particle manufactured by the method. According to the invention, by adding diol having 3 or more than carbon atoms before supplying the alkyltrialkoxysilane, polyalkylsilsesquioxane particle can be obtained which has a large diameter and a narrow distribution of particle sizes, while maintaining the property equal to or greater than the existing property. However, since the final result is limited to the polyalkylsilsesquioxane and the acid catalyst is used, the range is limited. Also, there are requirements for the selection and amount of the catalyst to be used, the selection of the reaction solvent, and a precise pH adjustment of the reaction solution, however, the adjustment is not easy. Further, there still remains a problem that the produced polymer loses high regularity, so that the solubility in the solvent is reduced. In particular, the invention does not disclose the structure and shape of the final result, so that structural stability is not obtained.

Method for manufacturing polysilsesquioxane by using carbon dioxide solvent and polysilsesquioxane manufactured using the same

KOREA INSTITUTE OF INDUSTRIAL TECHNOLOGY


A die bonding apparatus and a bonding method are provided wherein the apparatus comprises a bond head movable between a supply of semiconductor dice and a die bonding site, a pick-up tool attached to the bond head for holding a die to be bonded at the die bonding site and an optical assembly positioned for viewing an orientation of the die bonding site. The bond head is configured such that an orientation of the die being held by the pick-up tool between the optical assembly and the die bonding site is viewable by the optical assembly, whereby the orientation of the die may be aligned with the orientation of the die bonding site.

During the production of semiconductor dice or chips, many semiconductor dice are formed together on a single wafer. The wafer is then cut to separate the individual dice. Each of these semiconductor dice should then be individually mounted onto a support surface for further processing by utilizing a die bonding process. Thereafter, electrical connections are created between the dice and external devices, and the dice are later encapsulated with a plastic compound to protect them from the environment.
In prior art die bonders utilized in the said die bonding process, each individual die is usually picked up by a bond arm from the wafer and then transported to a substrate to perform attachment of the die onto the substrate. FIG. 1 is an isometric view of a die bonder 100 of the prior art. The die bonder 100 generally comprises a die bond head 102 which has an air nozzle 104 for creating a suction force to pick up a semiconductor die 106 from a wafer platform 108 holding the die 106. The die 106 is then transported and bonded onto a substrate 110.
In order to place the die 106 correctly and accurately onto the substrate 110, visual alignment is conducted with a vision system, usually comprising a first optical system 112 located over the wafer platform 108 and a second optical system 114 located over the substrate 110. Visual alignment is performed to capture images of the die 106 on the wafer platform 108 and the substrate 110. Positioning of the bond head 102 and air nozzle 104 will be performed according to the image captured of the die 106, which references an alignment pattern or fiducial mark on the die 106 for this purpose. Since the alignment pattern or fiducial mark of the die 106 is located on an upper side of the die facing the first and second optical systems 112, 114, these die bonders 100 allow the first optical system 112 to capture an image of the die 106 before the bond head 102 is moved into position to pick up the die 106, and to adjust the orientation of the die 106 according to the image taken of the substrate 110, before placing the die 106 onto the substrate 110.
A problem with this approach is that any error or unexpected movement of the die 106 that may be introduced during the die pick-up process after the image of the die 106 has been captured cannot be corrected or compensated for by the vision system. For example, an attraction surface of the air nozzle 104 and the die 106 may not be co-planar as a result of this error. The co-planarity between the air nozzle 104 and the die 106 is one of the major concerns during the pick-up process. When such co-planarity is not achieved, the position and angle of the die 106 will likely be shifted and rotated during the pick up process. It would be desirable to perform visual alignment of a die 106 after it has been picked up by the bond head 102 and before placement onto a substrate 110 to avoid errors introduced during die pick-up.
Furthermore, said prior art die bonders 100 that recognize the die 106 and the substrate 110 using two individual optical systems at two different locations require calibration. Calibration is needed to relate the coordinates as viewed by the optical systems with the coordinates of a bond head table (not shown) controlling positioning of the bond head 102. Any calibration error will have a direct adverse effect on the accuracy of the coordinate relationship existing between the two optical systems 112, 114 and the bond head table, and this will affect die bonding placement accuracy.
Also, during machine operation, the temperature of the bonding apparatus typically varies. Hence, the bond head table and optical systems 112, 114 may be heated up by their respective motors when the machine is running fast and may be cooled down when the machine is running slow or stopped. Thermal expansion or contraction will change the aforementioned relationship established between the optical systems and bond head table during calibration, thus affecting the placement accuracy as well. Generally, the further the two optical systems 112, 114 are separated, the worse the calibration error. This is because the calibration method usually involves the use of the bond head table to translate a calibration pattern from one optical system to the other. The distance of this movement should thus be accurately defined. The longer the distance, the larger is the effect of thermal error and table motion error.
Some die bonders may instead employ a movable optical system which can move from the location of the wafer platform 108 to the location of the substrate 110. The advantage of this design is that the images of both the die alignment pattern and the substrate alignment pattern can be captured with just one optical system, so that calibration for two individual optical systems need not be performed. Nevertheless, any motion error of such a movable optical system that is introduced when the optical system is moving between the location of the platform 108 to the location of the substrate 110 will also affect the placement accuracy.
When handling dice that are large or long in length, it will generally be better to employ an optical system with a small field of view. This means that if the optical system cannot capture the image of the whole die, it will need to capture the alignment pattern at one corner of the die 106 first and then move to capture the alignment pattern at an opposite corner of the die 106. In this way, the die centre position and the angle of rotation of the die can be calculated. A small field of view will provide the vision system with a higher resolution and thus higher pattern recognition (PR) accuracy. However, the motion accuracy of the optical system will also play an important part in the overall placement accuracy during die bonding. As explained above, another potential source of error may be introduced if positioning of the optical system is not sufficiently accurate. It would be desirable to minimize motion of the optical system used for visual alignment to avoid inaccuracy introduced from motion of the optical system.


A monomer of the formula: ##STR1## wherein R5, R6 and R7 are independently hydrogen, alkyl, cyano, alkyloxycarbonyl or carbamoyl; Z is a spacer or a direct link; and R is hydroxyalkyl having a protected terminal hydroxy, can produce a polymer useful for producting a resist composition.

The present invention relates to novel polymers useful, for example, for preparation of resist compositions used for production of semiconductor devices, etc., and novel acrylic or methacrylic acid derivatives usable as materials for said polymers.
Novolak resins and polymers comprising acrylic acid units or methacrylic acid units have been known as alkali-soluble resins. of these, various polymers have been put to practical use as materials for photolithography or materials for electronics industry, such as resist materials. Particularly in the lithography field, g-line light sources (wavelength 436 nm), i-line light sources (wavelength 365 nm) for ultraviolet light, and recently excimer lasers (KrF excimer laser: wavelength 248 nm, ArF excimer laser: wavelength 193 nm) are used as a light source for exposure. As the base polymer of a resist material suitable for each of these light sources, novolak resins are mainly used in resists for i-line or g-line light and phenolic resins are mainly used in resists for KrF excimer laser beams. Both the novolak resins and the phenolic resins have phenolic hydroxyl groups (pk.sub.a : about 12) as functional groups which permit development with an alkali developing solution.
On the other hand, acrylic acid derivative or methacrylic acid derivative resins are leading base polymers used in resist materials for ArF excimer laser beams which are under development (for example, JP-A 7-199467, JP-A 8-82925, JP-A 7-234511, etc.).
The reason is that conventional resins having aromatic rings have a low transparency in the deep ultraviolet region and are quite opaque at 193 nm, the wavelength of ArF excimer laser beams.
The resist materials obtained by using the acrylic or methacrylic resin as the base polymer, however, have a high acidity (pk.sub.a : about 5) because of their carboxylic acid groups as soluble groups and hence have a much rapider dissolution rate in alkali development than do the conventional polymers having phenolic hydroxyl groups as soluble groups. Therefore, they are disadvantageous in that when a 2.38% aqueous tetramethylammonium hydroxide (TMAH) solution, a conventional alkali developing solution is used without dilution, film peeling or dissolution of non-exposed portion occurs in the formation of a fine pattern, so that no satisfactory pattern can be obtained.
Moreover, the above-mentioned 2.38% TMAH is a leading alkali developing solution employed at present in an actual production line of semiconductor devices, so that it is very difficult to use a diluted developing solution in a production line in which there is used a combination of resist materials of different generations, such as a combination of a resist for i-line light and a resist for KrF excimer laser beams or a combination of a resist for KrF excimer laser beams and a resist for ArF excimer laser beams.

Acrylic or methacrylic acid derivatives and polymers obtained therefrom


A plasma display device and driving method thereof has a peak value of one frame is detected and then converted. A grayscale or a grayscale value is converted according to an original peak value and a converted peak value, and a total number of sustain pulses applied to the one frame is reset such that a brightness corresponding to the converted grayscale or grayscale value is set to be equal to a brightness corresponding to the original grayscale or grayscale value. In such a manner, the numbers of on-subfields and useable subfields corresponding to the grayscale of the input video signal are increased, so that the discharge characteristics are enhanced and the false contour is reduced.

1. Field of the Invention
Aspects of the present invention relate to a plasma display device and a driving method thereof. Aspects of the present invention relate to a plasma display device and a driving method where input grayscales are converted and the number of on-subfields and useable subfields corresponding to the grayscales of input videos are increased to enhance discharge characteristics and reduce false contours.
2. Description of the Related Art
A plasma display device is a display device that uses plasma generated by a gas discharge to display characters or images. In a plasma display device, a video signal of one frame is divided into a plurality of subfields respectively having a weight. Gray scales are expressed by a combination of the subfields of different weights. Each of the subfields include a reset period, an address period, and a sustain period. The reset period is for initializing the states of each discharge cell so as to facilitate an addressing operation of the discharge cell or cells. The address period is for selecting turn-on/turn-off of the discharge cells (i.e., discharge cells to be turned on or off) and accumulating wall charges in the discharge cells (i.e., the addressed discharge cells) that are in the turn-on state. The sustain period is for causing a discharge for displaying of an image using the addressed discharge cells.
However, when an input video signal data of the one frame is divided into a plurality of subfields and grayscales are displayed according to the on/off of the subfields as describe above, a false contour may be generated due to human vision properties. That is, when a moving image is displayed, a false contour phenomenon may occur in which a grayscale that is different from an actual one is perceived by human eyes because of the vision properties of the human eyes that follow the movement of the image.
In addition, when the number of the turned-on subfields is small when the grayscales are displayed according to the on/off of the respective subfields, a small amount of priming particles is generated. Accordingly, a discharge may not be sufficiently generated.

Plasma display device and driving method thereof


Apparatus and methods for attaching flexible or magnetic plates onto an imaging cylinder are provided. A drum apparatus of an imaging device includes an imaging cylinder having an outer surface and a magnetic foil attachable to the outer surface of the imaging cylinder. In a configuration with the magnetic foil attached to the outer surface of the imaging cylinder, at least one metal back plate can be attached to the imaging cylinder via magnetic coupling to the magnetic foil. In a configuration without the magnetic foil attached to the outer surface of the imaging cylinder, at least one flexographic plate can be attached to the imaging cylinder.

Computer-to-plate (CTP) is an imaging technology used in printing processes, in which image data is output directly from a computer to a printing plate by exposing the printing plate to light energy according to the image data. A printing plate is positioned on an imaging cylinder, e.g., the cylinder (also called a drum) of an external drum imaging device. As the cylinder rotates around its axis, an image head moves in the axial direction and focuses one or more laser beams modulated with image data onto an ablatable layer of the plate to ablate a pattern.
In general, printing plates may include any type of plate that is ablatable by light energy. Examples of printing plates include flexographic plates (sometimes referred to as "flexo plates") and metal back plates (sometimes referred to as "letterpress plates") that include a photopolymer material.
There are generally three different types of cylinder devices currently available for CTP imagers, dependent upon the types of printing plates being used. These devices include vacuum-based cylinder devices, magnetic cylinder devices and magnetic vacuum-based cylinder devices.
Conventional vacuum-based cylinder devices may be used to mount flexographic plates. They are not typically configured to mount metal back plates (such as letterpress plates). These devices include a cylinder coupled to a vacuum system. Flexographic plates are mounted to the cylinder by applying suction via the vacuum system.
Conventional magnetic cylinder devices may be used to mount metal back plates (such as letterpress plates). They are not typically configured to mount flexographic plates. The magnetic cylinder device typically includes a metal cylinder (such as aluminum) having a plurality of permanent magnets formed in the surface of the cylinder. Metal back plates are mounted to the cylinder by magnetic coupling via the permanent magnets.
Conventional magnetic vacuum-based cylinder devices may be used to mount metal back plates (such as letterpress plates) and flexographic plates. In addition to a metal cylinder having permanent magnets in the surface of the cylinder, the device includes a vacuum system coupled to the cylinder. For flexographic plates, suction is applied via the vacuum system. For metal back plates, the permanent magnets are used to magnetically couple the plates to the cylinder. When using flexographic plates on the cylinder, however, the cylinder surface (which include permanent magnets) may cause problems in an image of the flexographic plate. For example, the laser beam of a CTP imager may be reflected from the cylinder surface and may affect the image of the flexographic plate.
In general, vacuum-based cylinder devices are less expensive to manufacture than magnetic cylinder devices and magnetic vacuum-based cylinder devices. Magnetic vacuum-based cylinder devices are typically the most expensive to manufacture. The type of cylinder included with a CTP imager typically depends on the type of printing plates that will be used by a customer. For example, if only flexographic plates are to be used, the imager may be equipped with a vacuum-based cylinder device. If a user only uses metal back plates, the imager may be equipped with a magnetic cylinder device. If a user uses both metal and flexographic plates, the imager may be equipped with a magnetic vacuum-based cylinder device.
Another option for using both flexo and metal back plates on the same imager, aside from using magnetic vacuum cylinders, is to change the drums in the imager so as to use a vacuum-based cylinder device for flexographic plates and a magnetic cylinder device for metal back plates. However, this requires two drums, which is more costly than a single drum system, and may impact productivity because of the time needed to change the drums. Accordingly, there is a need for more cost effective apparatus and methods for permitting both flexo and metal back printing plates to be used on the same imager.

Method and apparatus for attaching flexographic and metal back plates on an imaging cylinder


The present disclosure relates to a method and a system for collecting and managing terminal use pattern information generated during a process of controlling screen display of a user terminal for eye protection and management. The method, according to the present disclosure, comprises the steps of: measuring a distance between a user terminal and a user; measuring a use time of the user terminal; converting and processing image information displayed on a screen of the user terminal by a predetermined image processing method, when the distance and/or the use time satisfy/satisfies a predetermined condition; and collecting terminal use pattern information comprising at least one of image conversion processing information, distance, and use time when a predetermined reaction is sensed from a user.

Recently, the advancement in the information and communication technology has enabled a wide spread of mobile communication terminals. The mobile communication terminal can provide not only a telephone function, but also various services desired by a user using various applications.
However, when using the service provided by the mobile communication terminal, the user stares at the screen unconsciously and unknowingly at a short distance for a long time continuously and repeatedly, while having a greatly reduced number of blinks of the eyes.
As such, excessive use of the eye may increase eye fatigue as well as cause dry eyes. In addition, when the dryness of the eyes is increased, there is a problem that the vision is blurred and the eyesight is greatly reduced. Further, the continuing work habit of staying close to the terminal for a long time increases the probability of developing myopia. Recently, statistics have continuously indicated a steep increase in the prevalence rate of myopia in East Asia, and, in particular, high myopia increases the risk of developing ophthalmic diseases such as retinal detachment, retinal tear, myopia macular degeneration, and the like.
In recent years, as the age group using the mobile communication terminals becomes increasingly younger, infants or children with less self-control are also experiencing a deterioration in eyesight, and therefore, there is a need for a technology that can automatically stop or restrict the operation when time of continuously using the mobile communication terminals by the infants or the children exceeds a certain time.
However, the related method of simply stopping or restricting the operations according to the use time of the mobile communication terminal has not been very helpful in reducing the deterioration in eyesight.

Terminal use pattern information collection management method and system

Industry-Academic Cooperation Foundation, Yonsei University