In an active-matrix driving type electro-optical apparatus including an increased number of image signal lines corresponding to an increased number of phases obtained by serial-to-parallel conversion, a liquid crystal apparatus includes a liquid crystal layer disposed between two substrates, pixel electrodes formed in a matrix fashion on a substrate, and TFTs serving for switching and controlling the pixel electrodes for suppressing the intrusion of high-frequency clock noise into an image signal. Image signal lines extend on the substrate at both sides of a data line driving circuit. The image signal lines are electrically shielded from clock signal lines, for example, by shielding lines formed on the substrate, and maintained at a constant voltage.

1. Field of the Invention The present invention relates to a technical field of an electro-optical apparatus such as an active matrix driving liquid crystal apparatus driven by thin film transistors (hereinafter also referred to as TFTs) or the like, and also to an electronic device using the same. More particularly, the present invention relates to an electro-optical apparatus in which data lines are driven at a high frequency by a data line driving circuit provided on a TFT array substrate in response to a control signal such as a clock signal, and also an electronic device using the same.
2. Description of Related Art
In conventional electro-optical apparatuses such as an active-matrix driving TFT liquid crystal apparatus, a great number of scanning lines and data lines are formed in horizontal and vertical directions, respectively, on a TFT array substrate, and a great number of pixel electrodes are formed at respective intersections of the scanning lines and the data lines. In some cases, in addition to the above elements, other elements are also formed on the TFT array substrate, such as data signal supply means including a data line driving circuit and a sampling circuit or the like and serving to supply a data signal to the data lines, and also a scanning signal supply means including a scanning line driving circuit or the like and serving to supply a scanning signal to the scanning lines.
In this case, a control signal such as a data line side reference clock signal which activates a data line driving circuit indicating a time reference for supplying a data signal, an image signal which corresponds to the content of images to be displayed and which is used as a basis on which the data signal is produced, and positive and negative constant electric potential power-supply or the like are supplied to the data signal supply means via external input terminals and wiring provided on the TFT array substrate, respectively. Similarly, a scanning line side reference clock signal which activates a scanning line driving circuit indicating a time reference for supplying a scanning signal, and positive and negative constant electric potential power-supply are supplied to the scanning signal supply means via external input terminals and wiring provided on the TFT array substrate. In the scanning signal supply means, for example, the scanning line driving circuit supplies a scanning signal over the scanning lines on the line-by-line basis in accordance with the scanning line side reference clock signal In response, in the data signal supply means, the data line driving circuit drives the sampling circuits, which serve to sample the input image signal, one by one in accordance with the timing indicated by the data line side reference clock signal. As a result, a data signal is supplied from the sampling circuits over the data lines. The respective TFTs whose gate is connected to one of the scanning lines turn on in response to receipt of the scanning signal supplied via the scanning lines. As a result, the data signal is supplied to the pixel electrodes via the corresponding TFTs and thus an image is displayed on the respective pixels.
In recent liquid crystal apparatuses, in particular in those for use in a liquid crystal projector, the frequency of serial image signals becomes increasingly high with the increase in the resolution of the image displayed. For example, the dot frequency of the image signal in the XGA display mode or SXGA display mode employed in recent high-resolution displays for personal computers is about 65 MHZ and 135 MHZ, respectively, which are much higher than the dot frequency in the conventional VGA mode (about 30 MHZ). As a result, a very high frequency is also required for the data line side reference clock signal supplied to the data signal supply means.
The increase in the frequency of the reference clock signals results in generation of high-frequency clock noise, which cannot be neglected, to achieve a high-quality display image. With the conventional technique of supplying a relatively low-frequency data line side reference clock signal to the data line driving circuit to drive the sampling circuit, if the frequency of the clock signal is simply increased, high-frequency clock noise intrudes into the image signal input to the sampling circuit or into the data signal output from the sampling circuit, and thus the data signal supplied to the data lines is degraded by the noise. The degradation in the data signal input to the respective pixels results in degradation in the image displayed by the respective pixels. For example, when a halftone image is displayed by the respective pixels, if noise as small as about 10 mV intrudes into the image signal, then visual noise appears in the displayed image. This is because, in the case of the halftone image, unlike the two-level display in which only white and black levels are displayed by applying a highest or lowest driving voltage (for example, 5 and 0 V) to a liquid crystal, the transmittance of the liquid crystal is very sensitive to the change in the voltage applied to the liquid crystal. Therefore, high-frequency clock noise is an important problem which has to be solved to realize a high-precision multi-level gray scale display.
If the number of phases into which the original image signal is serial-to-parallel converted is increased, it is possible to reduce the frequency of the image signals supplied to the sampling circuit. However, in this case, it is required to increase the number of external input terminals, which are provided on a substrate of a liquid crystal apparatus so as to input an image signal, depending on the number of phases of the serial-to-parallel-converted image signal. For example, when the serial-to-parallel conversion is performed into six phases, six external input terminals for inputting the image signal are required. In the case where the serial-to-parallel conversion is performed into twelve phases, twelve external input terminals are required. Furthermore, it is also required that there be as many wirings for transferring the image signal, input via the external input terminals, to the sampling circuit as there are serial-to-parallel conversion phases. As a result, the wirings for the image signal occupy a large area on the substrate of the liquid crystal apparatus. This makes it difficult to allocate a proper area on the substrate for forming the data signal supply means including the sampling circuit, the data line driving circuit, or the like. If wirings for control signals such as a clock signal are formed on a substrate in such a manner that they extend from an edge of the substrate where external input terminals are formed to one side of the data line driving circuit, and many wirings for image signals are formed on a substrate in such a manner that they extend to the other side if the data line driving circuit as is employed in the conventional technique, then the number of wirings extended to each side becomes very different between two sides of the data line driving circuit, so that the wiring balance in the surrounding of the data line driving circuit becomes quite bad (that is, wirings are concentrated on only one side). It is possible to increase the size of the substrate of the liquid crystal apparatus so that the wiring area and the data line driving circuit are disposed in the increased area. However, the increase in the size does not meet the requirement in the art of the liquid crystal apparatus for achievement of a large image display area using a limited size of substrate.
In view of the above, it is an object of the present invention to provide an electronic device including an electro-optical apparatus capable of displaying a high-quality image according to an input image signal or a data signal generated from the image signal with suppressed high-frequency clock noise.
It is another object of the present invention to provide a liquid crystal apparatus capable of displaying a high-quality image and also an electronic device provided with such a liquid crystal apparatus, in which a great number of wirings and a great number of external input terminals corresponding to a great number of serial-to-parallel-converted phases of an image signal are disposed in a well-balanced fashion and negative effects of high-frequency clock noise arising from control signals, such as a high-frequency clock signals, on the image signal are suppressed.
According to a first aspect of the present invention, to achieve the above objects, there is provided an electro-optical apparatus comprising a substrate and elements formed on the substrate, the elements including: a plurality of scanning lines; a plurality of data lines intersecting the plurality of scanning lines; a plurality of switching elements connected to the plurality of scanning lines and data lines; a plurality of pixel electrodes connected to the plurality of switching elements; data signal supply means for supplying, in response to a clock signal, a data signal corresponding to an image signal to the plurality of data lines; an image signal line for supplying the image signal input via a first external input terminal to the data signal supply means; a clock signal line for supplying the clock signal input via a second external input terminal to the data signal supply means; and an electrically conductive line maintained at a constant electric potential for shielding the image signal line from the clock signal line.
In accordance with these features of the invention, the image signal is input via the first external input terminal and supplied to the data signal supply means via the image signal line extending on the substrate. In parallel to the image signal, the clock signal is input via the second external input terminal and supplied to the data signal supply means via the clock signal line extending on the substrate. In response to this clock signal, the data signal supply means including, for example, a data line driving circuit and a sampling circuit or the like provided on a first substrate supplies the data signal corresponding to the image signal on the basis of the clock signal to the plurality of data lines. Herein, the image signal line is electrically shielded from the clock signal line by means of the electrically conductive line extending on the substrate and maintained at the constant electric potential, so that intrusion of high-frequency clock noise from the clock signal line to the image signal line is suppressed even when the clock signal has a high frequency.
On the other hand, a scanning signal is supplied to the switching elements via scanning lines by scanning signal supply means including a scanning line driving circuit formed on or connected to the substrate. Data signals corresponding to the image signals, whose clock noise is suppressed in the above-described manner, are supplied to respective switching elements via corresponding data lines. The voltages applied to the respective pixel electrodes by the data signals supplied via the switching elements vary in accordance with the applied data signals, and liquid crystals corresponding to the respective pixel electrodes are driven by the applied voltage. As a result, a high-quality image with a high resolution is displayed in accordance with the serial high-frequency image signal under the control of the high-frequency clock signal without having any or significant degradation in the image quality caused by high-frequency clock noise.
In this first aspect of the invention, the electrically conductive line preferably includes a part made up of a constant electric potential line for supplying a constant electric potential power-supply to the data signal supply means.
In accordance with these features of the invention, because the electrically conductive line includes the part made up of the constant electric potential line for supplying the constant electric potential power-supply to the data signal supplying means, it is possible to share an external input terminal and a wiring itself . In other words, it is possible to realize the electrically conductive line by extending the constant electric potential line. Thus it is possible to achieve simplification in structure and a reduction in space. Furthermore, it becomes very easy to maintain the electrically conductive line at a constant electric potential.
In another preferred mode of the first aspect of the present invention, the constant electric potential line includes first and second constant electric potential lines for supplying different constant electric potential power-supply to the data signal supply means, the part of the electrically conductive line formed of the first constant electric potential line surrounds the image signal line on the first substrate, and the part of the electrically conductive line formed of the second constant electric potential line surrounds the clock signal line on the substrate.
In accordance with these features of the first aspect of the invention, on the substrate, the image signal line is surrounded, for example, by the part of the electrically conductive line made up of the first constant electric potential line for supplying a negative power supply equal to a ground electric potential. On the other hand, on the substrate, the clock signal line is surrounded, for example, by the part of the electrically conductive line made up of the second constant electric potential line for supplying a positive power-supply. Thus, on the first substrate, the image signal line is doubly shielded, from the clock signal lines.
In still another preferred mode according to the first aspect of the invention, the data signal supply means includes a sampling circuit for sampling the image signal, and also includes a data line driving circuit which receives electric power supplied via the constant electric potential line and which drives the sampling circuit in accordance with the clock signal, and the image signal line and the clock signal line extend on the substrate in directions opposite to each other with respect to the data line driving circuit.
In accordance with these features of the invention, the image signal is sampled by the sampling circuit in the scanning signal supply means. In accordance with the clock signal, the sampling circuit is driven by the data line driving circuit which receives electric power via the constant electric potential line. The resultant sampled image signal is supplied as a data signal over the data lines. In this preferred mode, as described above, the image signal line and the clock signal line are formed such that they extend on the substrate in directions opposite to each other with respect to the data line driving circuit. In general, electromagnetic waves decay with distance, depending on the presence of an obstacle. Thus, electromagnetic waves applied to the image signal line from the clock signal line decrease depending on the distance between the image signal line and the clock signal line, and also depending on the presence of the data line driving circuit. Therefore, even when the clock signal has a high frequency, intrusion of high-frequency clock noise from the clock signal line to the image signal line is suppressed.
In a further preferred mode according to the first aspect of the present invention, the first and second external input terminals are disposed in a peripheral area of the substrate such that they are spaced from each other by a predetermined distance and a third external input terminal for inputting the constant electric potential power-supply to the constant electric potential line is disposed between the first and second external input terminals.
That is, in accordance with these features of the present invention, the first and second external input terminals are disposed in the peripheral area of the substrate such that they are spaced from each other by the predetermined distance via the third external input terminal, and more preferably, they are spaced as far apart as possible from each other within the area available for formation of the external input terminals on the periphery of the substrate. As a result of the above arrangement, the image signal line encounters less intrusion of high-frequency clock noise from the clock signal line compared with the case where the image signal line and the clock signal line are disposed close to each other.
In a yet further preferred mode according to the first aspect of the present invention, on the substrate, the electrically conductive line is extended such that the electrically conductive line surrounds an image display area defined by the plurality of pixel electrodes, and also surrounds the plurality of data lines.
That is, in accordance with these features of the present invention, because the image display area and the plurality of data lines are surrounded by the electrically conductive line on the substrate, the image display area and the plurality of data lines are shielded from the clock signal line. Thus, intrusion of high-frequency clock noise into the data signal output from the data signal supply means and to the data signal input to the switching elements or the pixel electrodes is suppressed.
In a different preferred mode according to the first aspect of the present invention, an electro-optical material is disposed between the substrate and an opposite substrate, and a light shielding frame is disposed on at least either the substrate or the opposite substrate, and furthermore the electrically conductive line includes a part formed on the substrate at a location opposite to the light shielding frame and along the light shielding frame.
That is, in accordance with these features of the present invention, because the electrically conductive line is disposed under the light shielding frame formed on the opposite substrate, the required space on the TFT array substrate is reduced. More specifically, it is possible to find a sufficient area on the periphery of the substrate for forming the scanning line driving circuit and the data line driving circuit without having a reduction in the effective image display area of the electro-optical apparatus caused by formation of the electrically conductive line.
In a different preferred mode according to the first aspect of the present invention, the electrically conductive line and the data line are formed of the same metal material with a low resistance.
In accordance with these features of the present invention, because the electrically conductive line is formed of the same metal material with a low resistance as that used to form the data lines, such as Al (aluminum), the electrically conductive line may extend along a long distance while maintaining the resistance of the electrically conductive line to a level low enough for practical use. That is, it becomes possible to extend the electrically conductive line in a zigzag fashion between other wirings or various circuits along a long distance or over a wide area including the image display area, without encountering a reduction in the shielding effects caused by the increase in resistance. Thus, it is possible to enhance the overall shielding effects using a rather simple structure. Furthermore, it is possible to form the electrically conductive line and the data lines using the same metal material with a low resistance in the same process during the production process of the electro-optical apparatus. That is, the increase in the processing steps resulting from the introduction of the electrically conductive line can be minimized.
In a different preferred mode according to the first aspect of the present invention, the part of the electrically conductive line formed between the image signal line and the clock signal line, the image signal line, and the clock signal line are formed from the same low-resistance metal layer formed in a single same plane parallel to the substrate.
In accordance with these features of the present invention, because the part of the electrically conductive line formed between the image signal line and the clock signal line, the image signal line, and the clock signal line are formed in the single same plane parallel to the substrate, it is possible to achieve further improved shielding effects. Herein, the xe2x80x9cformation in the same planexe2x80x9d includes the case where the above lines are formed directly on the substrate and also the case where the above-described lines are formed on an insulating layer formed on the substrate or the case where the above-described lines are formed on an interlayer insulating layer formed on a semiconductor layer in which TFTs and switching elements or the like are formed. Furthermore, because the electrically conductive line, the image signal line, and the clock signal line are formed from the same low-resistance metal layer, such as an Al layer, at the same time during the process of producing the electro-optical apparatus, the increase in the production processing steps caused by the introduction of the electrically conductive line is minimized.
In a preferred mode according to the first aspect of the present invention, there is provided a capacitance line for adding a predetermined magnitude of capacitance to the pixel electrode, wherein the capacitance line is connected to the electrically conductive line.
In accordance with these features of the present invention, because the predetermined magnitude of capacitance is added by the capacitance line to the pixel electrode, it becomes possible to display a high-precision image even when the duty ratio is small. Furthermore, because the capacitance line is connected to the electrically conductive line, it is possible to prevent negative effects of the variation in electric potential of the capacitance line on the switching elements and pixel electrodes. Furthermore, the electrically conductive line can also serve as a wiring for maintaining the capacitance line at a constant electric potential. Still furthermore, for example, the third external input terminal or the external input terminal for the electrically conductive line may be employed also as an external input terminal for inputting the constant electric potential at which the capacitance line is maintained.
According to a second aspect of the present invention, there is provided an electro-optical apparatus comprising a substrate and elements formed on the substrate, the elements including: a plurality of data lines; a plurality of scanning lines crossing the plurality of data lines; a plurality of switching elements connected to the plurality of data lines and the plurality of scanning lines; a plurality of pixel electrodes connected to the plurality of switching elements; a plurality of image signal lines supplied with image signals; a plurality of control signal lines supplied with control signals including a clock signal; and data signal supply means which receives the image signals and the control signals via the image signal lines and the control signal lines, and which supplies data signals corresponding to the image signals to the plurality of data lines in accordance with the control signals; wherein, on the substrate, a first group of image signal lines of the plurality of image signal lines extend to one side of the data signal supply means and a second group of image signal lines of the plurality of image signal lines extend, to the opposite side of the data signal supply means, and the electro-optical apparatus further comprises at least one electrically conductive line which is formed on the substrate so as to electrically shield the first and second groups of image signal lines from the plurality of control signal lines.
In this second aspect of the present invention, the image signals are input to the data signal supplying means via the image signal lines. In parallel with the image signals, the control signals including a clock signal and an enable signal or the like are supplied to the data signal supply means via the control signal lines. In response, the data signal supplying means including a data line driving circuit and a sampling circuit, for example, supplies the data signals corresponding to the image signals to the plurality of data lines on the basis of the control signals. The image signal lines are electrically shielded by the electrically conductive line formed on the substrate from the respective control signal lines including the clock signal line and the enable signal line or the like. Therefore, even when the clock signal has a high frequency, intrusion of high-frequency clock noise from the control lines such as a clock signal line to the image signal lines is suppressed.
On the other hand, a scanning signal is supplied to the switching elements via scanning lines from scanning signal supply means, including a scanning line driving circuit formed on or connected to the substrate. In parallel with this, data signals corresponding to the image signals, whose clock noise is suppressed in the above-described manner, are supplied to the respective switching elements via corresponding data lines. Thus, the voltages applied to the pixel electrodes vary in accordance with the data signals supplied via the switching elements and liquid crystals corresponding to the respective pixel electrodes are driven by the applied voltage.
Therefore, even when it is required to display a high-resolution image in accordance with image signals converted from a serial form into a parallel form consisting of a plurality of phases, it is possible to display the image with high quality without having any or significant degradation in the image quality caused by high-frequency clock noise. Furthermore, on the substrate, the first group of image signal lines extend to one side of the data signal supply means while the second group of image signal lines extend to the opposite side of the data signal supply means. Thus, it is possible to reduce the frequency of the image signals supplied to the data signal supply means by increasing the number of phases into which the original image signal is serial-to-parallel converted, for example, to 12 or 24 phases. The great number of image signal lines corresponding to the increased number of phases are disposed at both sides of the data signal supply means such that they are distributed in a well-balanced fashion. This makes it possible to easily find an area on the substrate for use as an area in which the sampling circuit or the data signal supply means including the sampling circuit and the data line driving circuit or the like is formed. Thus it becomes possible to form a large image display area on a substrate with a limited size.
In a preferred mode according to the second aspect of the present invention, the electrically conductive line shields the first and second groups of image signal lines from at least a high-frequency control signal line of the plurality of control signal lines, the high-frequency control signal line having a repetition period shorter than the horizontal scanning period of the image signals.
That is, in accordance with these features of the present invention, the image signal lines are electrically shielded from the high-frequency control signal line for supplying a high-frequency control signal (such as a clock signal and an enable signal) of the plurality of control signal lines by the electrically conductive line . Therefore, even when the clock signal has a high frequency, intrusion of high-frequency clock noise from the high-frequency control signal line to the image signal lines is suppressed. On the other hand, a low-frequency control signal (such as a start signal for a shift register in the data line driving circuit) does not cause high-frequency noise to the image signals or the data signals. Therefore, the low-frequency control signal line for supplying such a control signal may or may not be shielded by an electrically conductive line.
In another preferred mode according to the second aspect of the present invention, of the plurality of control signal lines, a low-frequency control signal line for supplying a low-frequency control signal having a repetition period which is, at least, not shorter than the horizontal scanning period of the image signals is disposed together with the electrically conductive line between the first and second groups of image signal lines and the high-frequency control signal line.
In accordance with these features of the present invention, of the image signal lines included in the first or second image signal line groups, an image signal line closest to the high-frequency control signal line is physically spaced apart and electrically shielded from the high-frequency control signal line by at least two wirings, including the low-frequency control signal line and the electrically conductive line. That is, the low-frequency control signal line for supplying a low-frequency control signal (such as a start signal for the shift register in the data line driving circuit) which does not cause high-frequency noise to the image signals or the data signals is disposed together with the electrically conductive line between the high-frequency control signal line and the image signal lines, thereby further reducing the negative effects, such as clock noise, of the high-frequency control signal line on the image signal lines. In general, electromagnetic waves decay with distance, depending on the presence of an obstacle. Thus, electromagnetic waves applied to the image signal lines from the high-frequency control signal line can be reduced by disposing as many electrically conductive lines and low-frequency control signal lines between the control signal lines and the image signal lines. Disposing a low-frequency control signal line, in addition to an electrically conductive line, between the high-frequency control signal line and the image signal lines results in efficient use of the space on the substrate and also a reduction in noise.
In still another preferred mode according to the second aspect of the present invention, the electro-optical device further comprises external input terminals formed in a peripheral area of the substrate, the external input terminals including: a plurality of first external input terminals connected to the first group of image signal lines, the plurality of first external input terminals serving to receive the respective image signal from an external image signal source; a plurality of second external input terminals connected to the second group of image signal lines, the plurality of second external input terminals serving to receive the respective image signal from the external image signal source; a plurality of third external input terminals connected to the control signal lines, the plurality of third external input terminals serving to receive the control signals from an external control signal source; and a plurality of fourth external input terminals connected to the electrically conductive lines, wherein the third external input terminals are disposed between the first and second external input terminals, and the fourth external input terminals are disposed between the first and third external input terminals and between the third and second external input terminals.
In accordance with these features of the present invention, as described above, the plurality of third external input terminals connected to the control signal lines are disposed on the periphery of the substrate such that they are located between the plurality of first and second external input terminals connected to the first and second groups of image signal lines, respectively. That is, in the peripheral area of the substrate where the first to fourth external input terminals are formed, the plurality of third external input terminals connected to the control signal lines are disposed in a central area in a concentrated fashion, and the first and second external input terminals connected to the first and second groups of image signal lines, respectively, are disposed at both sides of the third external input terminals. The fourth external input terminals connected to the electrically conductive lines are disposed between the first and third external input terminals and between the third and second external input terminals. That is, the first and second groups of image signal lines are spaced, on the substrate, apart from the control signal lines, and the electrically conductive lines are disposed in this space. This arrangement makes it possible to effectively prevent the image signals from encountering noise arising from the control signals such as a clock signal before the image signals are input to the electro-optical apparatus. Instead of employing the above arrangement according to the present invention, if the plurality of external input terminals connected to the image signal lines and those connected to the control signal lines are disposed in a mixed fashion in the same area or disposed at locations close to each other, then the image signals and the control signals are input to the electro-optical apparatus along wirings adjacent or close to each other, and thus noise such as clock noise intrudes into the image signals. However, in the present invention, intrusion of high-frequency clock noise from the clock signal line to the image signal lines is suppressed before and after the image signals are input to the electro-optical apparatus. More preferably, the first and second external input terminals are disposed at locations shifted to both side ends to as large a degree as possible in areas available for formation of the external input terminals on the periphery of substrate, and the first and second external input terminals are spaced as far apart as possible from the third external input terminals disposed between them, so that the fourth external input terminals connected to the electrically conductive lines are disposed in the spaces.
In a further preferred mode according to the second aspect of the present invention, the electrically conductive line shields the first and second groups of image signal lines from a high-frequency control signal line of the plurality of control signal lines, for supplying the high-frequency control signal having a repetition period which is, at least, shorter than the horizontal scanning period of the image signals, wherein, of the third external input terminals, the one adjacent to the fourth external input terminals is connected to a low-frequency control signal line of the plurality of control signal lines for supplying a low-frequency control signal having a repetition period which is, at least, not shorter than the horizontal scanning period of the image signals.
In accordance with these features of the present invention, the image signal lines are electrically shielded by the electrically conductive lines from the high-frequency control signal line. In particular, of the third external input terminals connected to the control signal lines, the third external input terminal located adjacent the fourth external input terminals connected to the electrically conductive lines is connected to the low-frequency control signal line. As a result, the image signal lines are physically spaced apart and electrically shielded from the high-frequency control signal line by at least two wirings including the low-frequency control signal line and the electrically conductive line.
In a yet further preferred mode according to the second aspect of the present invention, the electrically conductive line includes a part made up of a data line which drives a constant electric potintial lilne for supplying a power-supply which drives data lines of a constant electric potential to the data signal supplying means.
In accordance with these features of the present invention, because the electrically conductive line includes the part made up of the data line which drives a constant electric potential line for supplying a power supply which drives data lines of a constant electric potential to the data signal supplying means, it is possible to share an external input terminal and a wiring independent of the electrically conductive line and the constant electric potential line. In other words, it is possible to realize the electrically conductive line by extending the constant electric potential line. Thus it is possible to achieve simplification in structure and a reduction in space. Furthermore, it becomes very easy to maintain the electrically conductive line at a constant electric potential.
In a different preferred mode according to the second aspect of the present invention, the data line which drives a constant electric potential line includes first and second constant electric potential lines for supplying different constant electric potential power-supply to the data signal supplying means, the part of the electrically conductive line formed of the first constant electric potential line surrounds the first and second groups of image signal lines, on the substrate, and the part of the electrically conductive line formed of the second constant electric potential line surrounds the control signal lines on the first substrate.
In accordance with these features of the present invention, the first and second groups of image signal lines are surrounded on the substrate, for example, by the part of the electrically conductive line made up of the first constant electric potential line for supplying a negative power supply equal to a ground electric potential. The control signal lines are surrounded on the substrate, for example, by the part of the electrically conductive line made up of the second constant electric potential line for supplying a positive power supply. Thus, the image signal lines are doubly shielded from the control signal lines on the first substrate.
In a different preferred mode according to the second aspect of the present invention, the electrically conductive line is extended such that, on the substrate, the electrically conductive line surrounds an image display area defined by the plurality of pixel electrodes and also surrounds the plurality of data lines.
In accordance with these features of the present invention, because the image display area and the plurality of data lines are surrounded by the electrically conductive line on the substrate, the image display area and the plurality of data lines are shielded from the control signal lines such as the clock signal line. Thus, intrusion of high-frequency clock noise into the data signal output from the data signal supply means and to the data signal or the like input to the switching elements or the pixel electrodes is suppressed.
In a different preferred mode according to the second aspect. of the present invention, the electro-optical apparatus further comprises an opposite substrate located opposite to the substrate; and a light shielding frame disposed, along the contour of the image display area, on at least either the substrate or the opposite substrate, wherein the electrically conductive line includes a part formed on the substrate at a location opposite to the light shielding frame and along the light shielding frame.
In accordance with these features of the present invention, because the electrically conductive line is disposed on the substrate and under the light shielding frame, the required space on the TFT array substrate is reduced. More specifically, it is possible to find a sufficient area on the periphery of the substrate for forming the scanning line driving circuit and the data line driving circuit without having a reduction in the effective display area of the liquid crystal apparatus caused by formation of the electrically conductive line.
In a different preferred mode according to the second aspect of the present invention, the electrically conductive line and the data line are formed of the same metal material with a low resistance.
In accordance with these features of the present invention, because the electrically conductive line is formed of the same metal material with a low resistance as that used to form the data lines, such as Al (aluminum), the electrically conductive line may be extended along a long distance while maintaining the resistance of the electrically conductive line to a level low enough for practical use. That is, it becomes possible to extend the electrically conductive line in a zigzag fashion between other wirings or various circuits or the like along a long distance or over a wide area including the image display area or the like, without encountering a reduction in the shielding effects caused by the increase in resistance. Thus, it is possible to enhance the overall shielding effects using a rather simple structure. Furthermore, it is possible to form the electrically conductive line and the data lines using the same metal material with a low resistance in the same process during the production process of the electro-optical apparatus. That is, the increase in the processing steps resulting from the introduction of the electrically conductive line can be minimized.
In a different preferred mode according to the second aspect of the present invention, there is provided a capacitance line for adding a predetermined magnitude of capacitance to the pixel electrodes, wherein the capacitance line is connected to the electrically conductive line.
In accordance with these features of the present invention, because the predetermined magnitude of capacitance is added by the capacitance line to the pixel electrode, it becomes possible to display a high-precision image even when the duty ratio is small. Furthermore, because the capacitance line is connected to the electrically conductive line, it is possible to prevent negative effects from the variations in electric potential of the capacitance line on the switching elements and pixel electrodes. Furthermore, the electrically conductive line can also serve as a wiring for maintaining the capacitance line at a constant electric potential. Still furthermore, for example, the third external input terminal or the external input terminal for the electrically conductive line may be employed also as an external input terminal for inputting the constant electric potential at which the capacitance line is maintained.
In a different preferred mode according to the second aspect of the present invention, the electro-optical apparatus further comprises scanning signal supply means formed on the substrate, for supplying a scanning signal to said plurality of scanning lines line by line, wherein the electrically conductive line includes a part made up of a scanning line that drives a constant electric potential line for supplying a power supply which drives scanning lines of a constant electric potential to the scanning signal supply means.
In accordance with these features of the present invention, the image signal lines are electrically shielded from the control signal lines by the part of the electrically conductive line made up of the scanning line that drives a constant electric potential line. Therefore, even when the clock signal has a high frequency, intrusion of high-frequency clock noise from the control signal line to the image signal lines is suppressed.
In a different preferred mode according to the second aspect of the present invention, the scanning signal supply means is formed at both sides of an image display area defined by the plurality of pixel electrodes, and the part of the electrically conductive line made up of the scanning line that drives a constant voltage line is extended such that the part of the electrically conductive line surrounds the image display area and the plurality of data lines on the substrate and such that the scanning-line power-supply is supplied to the scanning line supply means in a redundant fashion.
In accordance with these features of the present invention, on the substrate, the image display area and the plurality of data lines are surrounded by the part of the electrically conductive line made up of the scanning line which drives a constant electric potential line so that the image display area and the plurality of data lines are also shielded by the control signal lines such as the clock signal line. Thus, intrusion of high-frequency clock noise or the like into the data signal output from the data signal supply means and to the data signal or the like input to the switching elements or the pixel electrodes is suppressed. Furthermore, because the part of the electrically conductive line made up of the scanning line that drives a constant electric potential line is extended such that the scanning-line driving power-supply is supplied in a redundant fashion to the scanning line supply means disposed at both sides of the image display area, even if breakage or disconnection occurs in the part of the electrically conductive line made up of the scanning line that drives a constant electric potential line or in other parts, the disconnection does not result in a fatal failure of the apparatus.
In a different preferred mode according to the second aspect of the present invention, the data signal supply means includes: a sampling circuit for sampling the image signal; and a data line driving circuit for driving the sampling circuit in accordance with the control signal, wherein the image signal lines included in the first group of image signal lines and the image signal lines included in the second group of image signal lines extend alternately in an area between the data line driving circuit and the sampling circuit at least every one or more image signal lines from both sides of the data line driving circuit in a comb fashion.
In accordance with these features of the present invention, the image signal lines included in the first group of image signal lines (for example, image signal lines VID1, VID3, VID5, VID7, . . . corresponding to the odd-numbered data lines) and the image signal lines included in the second group of image signal lines (for example, image signal lines VID2, VID4, VID6, VID8, . . . corresponding to the even-numbered data lines) extend alternately at least every one or more image signal lines from both sides of the data line driving circuit in the comb fashion. This allows the image signal lines and the data lines to be disposed in a systematic and well-balanced fashion around the data line driving circuit.
In a different preferred mode according to the second aspect of the present invention, the data signal supply means inverts the polarity of the voltage of the data signal every data line, wherein the image signal lines included in the first group of image signal lines and the image signal lines included in the second group of image signal lines extend, in a comb form, alternately every two image signal lines corresponding to adjacent two data lines from both sides of the data line driving circuit.
In accordance with these features of the present invention, the polarity of the voltage of the data signal is inverted line by line by the data signal supply means in a manner called 1S inversion, or dot inversion, thereby suppressing flicker in the displayed image. In this mode, the image signal lines included in the first group of image signal lines (for example, image signal lines VID1, VID2, VID5, VID6, . . . corresponding to two adjacent data lines, every four data lines) and the image signal lines included in the second group of image signal lines (for example, image signal lines VID3, VID4, VID7, VID8, . . . corresponding to two adjacent data lines, every four data lines) extend alternately every two image signal lines corresponding to adjacent two data lines, from both sides of the data line driving circuit in the comb fashion. As a result, the image signals supplied to two adjacent image signal lines become opposite in polarity to each other. Thus, noise components arising from the same noise source are canceled out between two adjacent image signal lines, and thus noise is suppressed.
The electro-optical apparatus according to the first or second aspect of the present invention may be used in an electronic device.
The electronic device provided with the electro-optical apparatus according to the present invention has the advantage in that high-frequency clock noise or the like is suppressed, and a high-quality image can be displayed.
These and other features and advantages of the present invention will become more apparent from the following detailed description referring to preferred embodiments.

Electro-optical apparatus and electronic device


In one embodiment, the input circuit includes a receiver circuit that generates a data signal based on a pair of differential data signals. A detecting circuit detects an offset voltage between the pair of differential data signals, and an adjusting circuit adjusts operation of the receiver to reduce a magnitude of the detected offset voltage based on the detected offset voltage.

FIG. 1 illustrates a prior art memory system. As shown, a memory controller 110 outputs a pair of differential data signals DQ and DQN to a memory module 120; for example, during a write operation. The memory module 120 includes a plurality of memory devices 122. Each memory device 122 may receive a pair of differential data signals DQ and DQN through each of a plurality of data signal lines on the motherboard. More specifically, each memory device 122 includes an input circuit 124 for receiving the differential data signals DQ and DQN and outputting a data signal represented by the differential data signals DQ and DQN. A memory section 126 of the memory device 122 may store the data represented by the data signal.
While not shown, it will be appreciated that a memory device 122 may also output differential data signals to the memory controller 110; for example, during a read operation (e.g., reading data from a memory section 126 of a memory device 122). And, while not shown, the memory controller 110 also includes an input circuit for receiving the differential data signals and generating a data signal therefrom.
For the purposes of explanation only, operation of the input circuit 124 at a memory device 122 will be described; however, it will be understood that the same operation may occur at the memory controller 110.
FIG. 2 illustrates portions of the conventional memory system in greater detail. As shown, at the memory controller 110, a well-known differential driver 112 generates the pair of differential data signals DQ and DQN based on input data D and DN, where DN is a voltage representing the logical inverse of that represented by the voltage D.
The first differential data signal DQ travels to the input circuit 124 of a memory device 122 via a first path PATH1 and the second differential data signal DQN travels to the input circuit 124 via a second path PATH2. The input circuit 124 is a differential amplifier DA that differentially amplifies the differential data signals to generate a data signal DATA.
FIG. 3A illustrates a waveform diagram of ideally generated differential data signals for data alternating between logic high and logic low, and FIG. 3B illustrates a waveform of a data signal generated from the ideal differential data signals. As shown by FIG. 3A, the second differential data signal DQN is ideally the inverse of the first differential data signal DQ such that the first and second differential data signals DQ and DQN transition between the same low and high voltages. As such, the first and second differential data signals DQ and DQN form an eye pattern wherein (1) each eye representing a logic low data signal has height HI equal to the height H2 of each eye representing a logic high data signal and (2) each eye representing a logic low data signal has a time interval or width W1 equal to the width W2 of each eye representing a logic high data signal. As further shown in FIG. 3A, the DC voltage VDC1 of the first differential data signal DQ is the same as the DC voltage VDC2 of the second differential data signal DQN such that no offset between the DC voltages VDC1 and VDC2 exists.
Because of the ideal characteristics of the first and second differential data signals, the resulting data signal has an ideal duty ratio of 50% as shown in FIG. 3B. Namely, the logic high periods of the data signal have the same time length as the logic low periods of the data signal. It should be understood that in normal operation, the differential data signals may represent logic high for two or consecutive periods and may represent logic low for two or more consecutive periods; however, the lengths of a single logic high period and a single logic low period define the duty ratio.
Unfortunately, in practice, the voltage swings of the first and second differential data signals DQ and DQN are not necessarily the same. Due to imperfect manufacturing tolerances, chip mismatch and/or channel mismatch may cause the differential data signals DQ and DQN as received at the input circuit 124 to differ from the ideal.
FIG. 3C illustrates one example case of how the differential data signals DQ and DQN may differ from the ideal shown in FIG. 3A. As shown, the voltage swings of the differential data signals DQ and DQN differ such that (1) each eye representing a logic low data signal has height H1 that is less than the height H2 of each eye representing a logic high data signal and (2) each eye representing a logic low data signal has a time interval or width W1 that is less the width W2 of each eye representing a logic high data signal. As a result, the data signal, as shown in FIG. 3D, may be erroneously generated (e.g., logic low state may not be detected or timely detected), and the data signal will have a duty ratio greater 50%. In that case, the logic low data of the data signal DATA may not be written into the memory cell array of the memory device 122 due to the lack of set up and hold time of the logic low data. Indicative of these conditions, the DC voltage VDC1 of the first differential data signal is greater than the DC voltage VDC2 of the second differential data signal. Thus a DC offset voltage exists between the first and second differential data signals.
FIGS. 3E and 3F illustrate yet another example of non-ideal differential data signals and the resulting data signal. As in the example of FIGS. 3C and 3D, a positive DC offset voltage exists because VDC1 is greater than VDC2; however, it will be appreciated that numerous other example situations exist in which a negative DC offset voltage (i.e., where VDC1 is less than VDC2) occurs. When a negative DC offset voltage occurs, the duty ratio of the resulting data signal may be less than 50%.

Input circuit for a memory device, and a memory device and memory system employing the input circuit


An apparatus for collecting foreign materials such as rocks and tramp iron from material fed to a rotary dryer, wherein the material is dropped into the dryer at an intake end for tumbling within the dryer in a stream of drying gas flowing axially through the dryer. A trough is positioned spaced downwardly and beneath the intake for catching the heavy foreign materials dropping downwardly, and the foreign materials are carried outwardly by a screw auger driven by the dryer.

The present invention relates to improvements in rotary drying systems, and more particularly to an improved hog fuel dryer wherein contamination of the fuel such as rocks and foreign material are removed so that they will not be transported through the dryer and cause damage.
Dryer systems are used for many purposes, including drying sludge prior to disposal, drying crops prior to further processing and drying fuel prior to combustion.
Fuel drying systems are widely used, and the interest in such systems results from the proven fact that dry fuel increases boiler efficiency. Drying of the fuel prior to being supplied to a boiler is highly advantageous in that if the drying is done inside the boiler, some of the energy which could be used to generate steam is instead consumed to dry incoming fuel. Boilers are inefficient dryers and the effect of wet fuel on the boiler performance is dramatic. Drying fuel in advance of the boiler results in more available BTU's per pound of fuel, as well as increased boiler efficiency. Drying also allows the effective control of fuel moisture content as moisture varies by season and with the composition of raw material. The consistency of the fuel moisture also contributes to more efficient and predictable boiler performance.
A commonly used fuel dryer operates on the rotary principle, wherein a rotary drum is fed with the fuel, and heated gases remove moisture from the fuel. Such a dryer can increase boiler efficiency by 10% or more. For example, if fuel is burned at a 55% moisture content in a boiler with a 500.degree. F. flue gas temperature, drying can be conducted to substantially reduce the moisture to combustion sustaining levels. If the moisture content of the fuel is reduced from 55% to 33%, the boiler efficiency will increase from approximately 57% to about 68%, thereby increasing boiler efficiency by more than 10%.
Rotary dryers are used commonly to dry fuel in industries such as the pulp and papermaking industry. In such industry, naturally occurring fuel, such as hog fuel, is widely available, and such fuel often becomes contaminated with rocks and foreign material. If the rocks and foreign material are permitted to enter a rotary dryer, extensive damage can result to flights and other internal components of the dryer. Since the material being dried is carried, at least in part, by the airstream through the dryer, the foreign elements, which are often much heavier than the fuel, cannot otherwise get out of the drum, due to the nature of the dryer construction. The foreign material tumbles the length of the dryer or concentrates in one area, in either case being tumbled at length by the dryer vanes or flights. Large or heavy foreign material, such as rocks, can cause significant damage, while being tumbled in the dryer.


Cell culture conditions were developed which maintain the nerve cells of the retina in well-defined, serum-free conditions. The molecular factors that stimulate axonal regeneration from these neurons were characterized. The glial sheath cells that surround the axons of the optic nerve release two molecules that trigger and sustain nerve regeneration. One of the molecules is referred to as axogenesis factor 1 (AF-1), and is a low molecular weight polypeptide with a size in the range of 1000 daltons. The second molecule, AF-2, is a larger protein with a size of approximately 12,000 daltons. Studies indicate that these factors are strongly involved in CNS regeneration, and are therefore useful in the treatment of spinal cord and other nervous tissue damage.

The present invention is generally in the area of methods and treatments for central nervous system injury, and particularly the use of trophic factors for spinal cord regeneration.
Past early childhood, injury to the central nervous system (CNS) results in functional impairments that are largely irreversible. Within the brain or spinal cord, damage resulting from stroke, trauma, or other causes can result in life-long losses in cognitive, sensory and motor functions, and even maintenance of vital functions. Nerve cells that are lost are not replaced, and those that are spared are generally unable to regrow severed connections, although a limited amount of local synaptic reorganization can occur close to the site of injury. Functions that are lost are currently untreatable.
Regenerative failure in the CNS has been attributed to a number of factors, which include the presence of inhibitory molecules on the surface of glial cells that suppress axonal growth; absence of appropriate substrate molecules such as laminin to foster growth; and an absence of the appropriate trophic factors needed to activate programs of gene expression required for cell survival and differentiation.
By contrast, within the peripheral nervous system (PNS), injured nerve fibers can regrow over long distances, with eventual excellent recovery of function. Within the past 15 years, neuroscientists have come to realize that this is not a consequence of intrinsic differences between the nerve cells of the peripheral and central nervous system; remarkably, neurons of the CNS will extend their axons over great distances if given the opportunity to grow through a grafted segment of PNS (e.g., sciatic nerve). Therefore, neurons of the CNS retain a capacity to grow if given the right signals from the extracellular environment. Factors which contribute to the differing growth potentials of the CNS and PNS include partially characterized, growth-inhibiting molecules on the surface of the oligodendrocytes that surround nerve fibers in the CNS, but which are less abundant in the comparable cell population of the PNS (Schwann cells); molecules of the basal lamina and other surfaces that foster growth in the PNS but which are absent in the CNS (e.g., laminin); and trophic factors, soluble polypeptides which activate programs of gene expression that underlie cell survival and differentiation. Although such trophic factors are regarded as essential to maintaining the viability and differentiation of nerve cells, the particular ones that are responsible for inducing axonal regeneration in the CNS remain uncertain.
In contrast to man and other higher vertebrates, lower vertebrates are able to regenerate injured CNS pathways throughout life (Sperry, R. W. (1944), J. Neurophysiol., 7:57-69; Sperry, R. W. (1963), Proc. Nat. Acad. Sci. USA, 50:703-710). In the goldfish, 95% of retinal ganglion cells survive injury to the optic nerve (Meyer, et al., (1985), J. Comp. Neurol., 239:27-43) and go on to re-establish topographically organized, functional connections with cells of the optic tectum and other target areas within one to two months (reviewed in Grafstein, (1986), The retina as a regenerating organ, In R. Adler and B. D. Farber (Eds.), The Retina: A Model for Cell Biology Studies Part II, Academic Press, New York, 275-335; Jacobson, (1991), Development Neurobiology, third edition (Plenum Publishing Co., New York)). The cellular and molecular changes that accompany this process have been studied in depth. Retinal ganglion cells undergo extensive metabolic and morphological changes that include a dramatic enlargement of the nucleolus, a proliferation of free ribosomes, and an increase in cell diameter (Murray & Grafstein, (1969), Exp. Neurol., 23:544-560; Murray & Forman, 1971 (1971), Brain Res., 32:287-298). Massive increases are seen in the expression of genes encoding certain components of the cytoskeleton (Burrell, et al., (1978), J. Neurochem., 31:289-298; Heacock & Agranoff, (1982), Neurochem. Res., 7:771-788; Giulian, et al., (1980), J. Biol. Chem., 255:6494-6501; Quitschke & Schechter, (1983), Brain Res., 258:69-78; Glasgow, et al., (1994) EMBO J., 13:297-305; Glasgow, et al. (1992) Neuron, 9:373-381), cell surface adhesion molecules (Vielmetter, et al., (1991) J. Neurosci, 11:3581-3593; Bastmeyer, et al., (1990) Development, 108:299-311; Paschke, et al., (1992) J. Cell Biol., 117:863-875; Blaugrund, et al., 1990; Battisti, et al., (1992) J. Neurocytol., 21:557-73), and several proteins that become incorporated into the growing nerve terminal membrane, particularly GAP-43 (Benowitz, et al., (1981) J. Neurosci., 1:300-307; Heacock & Agranoff, (1982); Perrone-Bizzozero, et al., (1987), J. Neurochem., 48:644-652; Perry, et al., (1987), J. Neurosci., 7:792-806; LaBate & Skene, (1989), Neuron, 3:299-310; Wilmot, et al., (1993), J. Neurosci., 13:387-401). Some of the same changes are associated with the development and regeneration of the optic nerve in other species (Skene & Willard, (1981), J. Cell Biol., 89:86-95 J. Cell. Biol., 89:96-103; Moya, et al., (1988), J. Neurosci., 8:4445-4454; Doster, et al., (1991), Neuron, 6:635-647).
In general, the capacity of neurons to regenerate their axons after injury is strongly influenced by the surrounding non-neuronal elements (Aguayo, et al., (1991) Phil. Trans. Royal Soc. London, Series B, 331:337-343). In the case of the goldfish retinofugal pathway, the glial sheath cells of the optic nerve seem to provide an environment that is highly conducive to axonal outgrowth (Bastmeyer, et al., (1993) Glia, 8:1-11; Bastmeyer, et al., (1991) J. Neurosci, 11:626-640). In part, this may be attributed to the expression of particular cell surface and extracellular matrix proteins, including an L1-like cell adhesion molecule (Blaugrund, et al., (1990) Brain Res., 530:239-244; Bastmeyer, et al., (1993); Bastmeyer, et al. (1991); Vielmetter, et al., 1991; Battisti, et al., 1992), laminin (Hopkins, et al., (1985) J. Neurosci., 5:3030-3038), and chondroitin sulfate proteoglycans (Battisti, et al., 1992). At the same time, optic nerve glia of goldfish seem to express lower levels of growth-inhibiting proteins on their surfaces than mammalian CNS oligodendrocytes (Caroni & Schwab, (1988) J. Cell Biol., 106:1281-1288; Schwab & Caroni, (1988) J. Neurosci., 8:2381-2393; Bastmeyer, et al., 1991; Sivron, et al., (1994), Presence of growth inhibitors in fish optic nerve myelin: postinjury changes. J. Comp. Neurol., 343:237-246).
In addition to cell surface components, cells of the goldfish optic nerve secrete soluble factors that promote axonal outgrowth from goldfish retinal explants (Mizrachi, et al., (1986) J. Neurochem., 46:1675-1682), embryonic mammalian neurons (Finkelstein, et al., (1987) Brain Res., 413:267-274; Caday, et al., 1989), and the mature rabbit retina (Schwartz, et al., (1985) Science, 228:600-603). Among the proteins that are secreted by the glia and microphages of the optic nerve are apolipoprotein A (Harel, et al., (1989) J. Neurochem., 52:1218-1228), a plasminogen activator (Salles, et al., (1990) EMBO J., 9:2471-2477), interleukin-2 (Eitan, et al., 1992), a transglutaminase (Eitan and Schwartz, (1993) Science, 261:106-108), and platelet-derived growth factor (Eitan, et al., (1992) Proc. Natl. Acad. Sci. USA, 89:5442-5446).
Despite these findings, the factors responsible for initiating axonal outgrowth from retinal ganglion cells remain unknown. Studies directed towards this issue have generally been carried out either in vivo or have utilized retinal explants derived from animals in which regeneration had already been triggered in vivo by a conditioning lesion (Landreth and Agranoff (1976) Brain Res., 118:299-303; Landreth and Agranoff (1979) Brain Res., 161:39-53; Turner, et al., (1981) Brain Res., 204:283-294; Turner, et al. (1982) Dev. Brain Res., 4:59-66; Schwartz, et al., 1985; Yip & Grafstein, (1982) Brain Res., 238:329-339; Hopkins, et al., 1985; Lima, et al., (1989) Int. J. Devl. Neuroscience, 7:375-382). The fact that various agents tested fail to augment outgrowth unless the regenerative process had already begun in vivo suggests that the factors required to initiate regeneration may derive from a source that is absent in the explant cultures, e.g., the optic nerve glia, the circulatory system, or other brain tissue (Johnson and Turner, (1982) J. Neurosci. Res., 8:315-329). Trophic factors are generally reviewed in Developmental Neurobiology, M. Jacobson (Third Edition, Plenum Publ. Co., NY 1991, Chapters 8 and 11); Molecular Neurobiology, Z. Hall, editor (Sinauer Publ. Co., Sunderland, Mass. 1992, Chapters 11 and 12).
It is therefore an object of the present invention to provide a method for obtaining molecular signals that initiate regeneration of nerve connections in mammals.
It is a further object of the present invention to provide factors which initiate regeneration of nervous tissue in mammals.
It is another object of the present invention to provide methods for treatment of injuries to spinal cord and other central nervous system tissue.

Trophic factors for central nervous system regeneration


In various embodiments, security may be provided for application to application (A2A) and application to database (A2DB) implementations. In some embodiments, a method comprises receiving a registration request at a first digital device for a first application, receiving a first program factor associated with the first application, confirming the first program factor, generating a first password for a second application based, at least, on the confirmation of the first program factor, and providing the first password to a second digital.

1. Field of the Invention
The present invention relates generally to application-to-application (A2A) or application-to-database (A2DB) security. More particularly, the invention relates to systems and methods for A2A and A2DB security using program authentication factors.
2. Description of Related Art
Often too many users of a network are granted full, unrestricted superuser, root, or administrator privileges, regardless of whether or not they need this access all the time and regardless of whether they need access to perform their current duties. This "all trusting" environment is frequently coupled with a lack of accountability of this access. Unfortunately, these privileged accounts are often exploited by unethical insiders and hackers to perpetrate fraud, theft, and damage.
A similar issue exists with non-human processes in the area of application-to-application (A2A) or application-to-database (A2DB) communication involving service accounts on various IT systems. The passwords for these accounts are often hard-coded or embedded in the calling application or script and rarely, if ever, changed. Couple this with the fact that any skilled administrator or programmer with access to the application source code or script can view those passwords, and the potential damage associated around exploitation moves to a higher dimension that may be even harder to spot and prevent.
Due to the depth of access that privileged and embedded passwords provide to highly sensitive and confidential information, and the fact that these access credentials are shared among administrators, it is only natural that security experts and compliance auditors are recommending and requiring more scrutiny and control in this area. Without a system of checks and balances and overall accountability for privileged and embedded passwords, an organization lays itself open to exploitation and exposes its mission-critical systems to intentional or accidental harm and malicious activity that is difficult and costly to repair.

Systems and methods for A2A and A2DB security using program authentication factors


A flexible energy-carrying circuit device has reduced flame retardancy while maintaining desired levels of adhesion between the energy-carrying filaments and the substrate with use of a flame-retardant pressure-sensitive adhesive comprised of a polymer of one or more acrylic esters with bromine and phosphorous compounded into the polymer to provide an adhesive having inherent flame retardancy. Small quantities of antimony trioxide may be dispersed in the adhesive to enhance flame retardancy.

A flexible energy-carrying circuit device may involve use of a pressure-sensitive adhesive to adhere energy-carrying filaments of the device to a substrate. For example, FIG. 1 shows a fragmented cross-sectional view of a typical flexible optical circuit apparatus in which an adhesive is used to secure the fibers to a substrate. The apparatus 10 comprises a plurality of optical fibers 12, encapsulated in an encapsulating sheet 14, such as polyurethane, nylon, polypropylene, KAPTON,.TM. doped MYLAR,.TM. or aluminum foil. The encapsulating sheet 14 protects the optical fibers, provides structural stability, and keeps the fibers in place during handling, yet it also should be flexible so that the apparatus may be mounted in an appropriate structure or connected to other systems or machines. A pressure-sensitive adhesive 16 is used to adhere the encapsulated fibers to a substrate 18. The substrate 18 is typically comprised of a flexible plastic and advantageously is fabricated with a polymer of the type commercially identified as KAPTON.TM., which is non-flammable and does not melt. A material that previously has been used for the pressure-sensitive adhesive 16 comprises number 711 adhesive, a resin available from Adchem Corporation of Westbury, N.Y. For further background regarding fiber optic structures, encapsulation techniques, and materials and methods used in these structures, see U.S. Pat. No. 5,582,673 to Burack and Ling et al (inventors herein), issued Dec. 10, 1996, entitled "Optical Fiber Encapsulation Techniques," and U.S. Pat. No. 5,259,051 to Burack et al. (an inventor herein), issued Nov. 2, 1993, entitled "Optical Fiber Interconnection Apparatus and Methods of Making Interconnections," both of which are hereby incorporated by reference.
A drawback with this structure, however, is that the encapsulating sheet 14 particularly when comprised of thermoplastic material may melt when heated, affecting the structural integrity of the apparatus. More importantly, when the thermoplastic melts, for example, in response to a flame, it may expose the adhesive 16 to the air, causing the adhesive when flammable to ignite. Also, the temperature of these devices as well as other electronic devices employing adhesives may increase during operation, leading to flammability concerns.
It is desirable that optical circuits and other energy-carrying devices meet certain levels of flame retardancy. Optical circuits and electronic devices are tested for flame retardancy pursuant to standards known in the industry for measuring the flammability of plastics used in electronic devices and appliances, namely, the Underwriters' Laboratory (UL) 94 standards. The UL standards are well known and are also described in M. Robert Christy, Standards, Bans, and Flame Retardants, PLASTICS COMPOUNDING (September/October 1993), at pp. 59-61. The UL 94 vertical (UL94V) standards have been applied to optical circuit devices, including the UL94V test and the 94VTM test, with the latter test (94VTM), applicable for thinner materials prone to distortion.
The flammability of optical circuits and energy-carrying devices has been addressed in many ways, including reconfiguring the devices and replacing the thermoplastic materials with materials having higher melting points. For example, one method has been to apply a second layer of KAPTON.TM. or other non-flammable coversheet 20 (FIG. 1A), over the thermoplastic encapsulant, which protects the thermoplastic and reduces the likelihood that it will melt. Another method involves rolling the system into a cylinder with the KAPTON.TM. substrate 18 facing out (FIG. 1B). U.S. Pat. No. 5,582,673, referenced above, describes encapsulation techniques involving materials other than thermoplastic in addressing flammability issues. While these methods are effective in reducing the flammability of the circuit overall, they limit the flexibility of the device and the configurations in which, and materials with which, the device can be fabricated. It would be beneficial to have a method of adhering the optical fibers to the substrate which avoids the use of flammable adhesives or involves adhesives having reduced flammability.
Developing pressure-sensitive adhesives that have good adhesive properties and yet are non-flammable and suitable for use in fiber optic and other energy-carrying devices has presented many challenges. A pressure-sensitive adhesive may be defined as a material that bonds surfaces at room temperature and with the application of some (and preferably a low) pressure. Typically, materials with good adhesive, cohesive, and tack qualities are also flammable. Pressure-sensitive materials based on acrylates or polyacrylates, for example, are tough, resilient, and flexible materials that have excellent pressure-sensitive adhesive properties, but they are also flammable.
Typically, to reduce the flammability of a pressure-sensitive adhesive, combustion-inhibiting compounds have been added to the adhesive. The most commonly-used additive is antimony trioxide which often is used in combination with halides, such as titanium tetrachloride. Making an adhesive flame retardant can be more complicated, however, than simply adding the combustion-inhibiting material, because the additive may disrupt the sensitive balance of properties of the material. For example, certain phosphates, while combustion-inhibiting, will greatly weaken the cohesive properties of the adhesives and cannot effectively be used.
The use of combustion-inhibiting additives has been found to be impractical for optical circuits. For the circuits to meet desired levels of flame retardancy as previously discussed, quantities of combustion-inhibiting additives at greater than twenty-five percent of the total solids would have to be added to the adhesive. However, typical flame retardant systems such as those based upon antimony oxide tend to settle out of acrylic coatings and adhesives, and they opacify the polymer and detract from its adhesive properties. Thus, the addition of sufficient quantities of combustion-inhibiting additives to meet flame-retardancy standards decreases the tack of the adhesives to the point that they can no longer meet desired fiber placement tolerances.
Thus, there is a need for a method of adhering energy-carrying filaments and particularly optical fibers to a substrate which avoids the use of flammable adhesives or which reduces the flammability of the adhesives while maintaining the adhesive qualities to a degree sufficient for such applications. This invention addresses this need. Further advantages may appear more fully upon consideration of the description below.

Flexible filament device with pressure-sensitive flame retardant adhesive


An apparatus (10) for rotary extraction of weeds and other vegetation by hand or by using a power driver. The apparatus includes a hollow guide tube (20) in which a shaft (16) is slidably disposed. An extraction head having a plurality of pointed rods (12) or prongs (62) is coupled to shaft (16), and can be extended or retracted by movement of shaft (16) within the guide tube (20). The rods (12) or prongs (62) are extended and inserted into the soil over the vegetation to be removed. Rotation of the apparatus winds the vegetation and its root around the rods (12) or prongs (62) and removes it from the soil. The vegetation is then ejected from the apparatus by retracting the rods (12) or prongs (62) and, if necessary, sliding the vegetation off of the tapered sleeve (30).

1. Field of the Invention
This invention pertains generally to weed extraction devices, and more particularly to a device for rotary removal of weeds without entanglement.
2. Description of the Background Art
Weed removal from plant beds, lawns, and other vegetated areas can be a tedious task. To ease the removal of weeds, a number of devices have been developed which include forks, tines or cutters which can be forced into the soil surrounding the weed and operated to either extract or cut the weed. When weeds are cut, however, the root system remains and the weed will grow back over a period of time. Therefore, rotary extraction is preferred since the root can be removed intact.
Rotary extraction devices heretofore developed suffer from various disadvantages, most notably that the extracted weed becomes entangled in the device and ejection of the weed from the extraction head is difficult. As a result, the user must unwrap or cut the weed in order to remove it from the device. Therefore, a need exists for a rotary weed extraction tool which can effectively remove the weed and its roots, while at the same time providing for ease of ejection of the weed and minimizing entanglement.


A jounce stop apparatus for use in a motor vehicle includes a resilient jounce bumper (36) attached to a frame member and a jounce bumper barrier (50) attached to an axle housing (12) for receiving the resilient jounce bumper and thereby limiting upward travel of the axle housing. The jounce bumper barrier includes a first portion (54) for attaching the jounce bumper barrier to the axle housing. Second, third and fourth portions (58, 62, 72) are arranged to generally form a U-shape. The third portion (62) includes an impact face (68) for receiving the jounce bumper during extreme upward travel of the axle housing relative to the frame.

1. Field of the Invention
The present invention relates generally to suspensions for motor vehicles. More particularly the present invention relates to an improved jounce stop apparatus which is less expensive and lighter weight than previous jounce stop apparatus.
2. Disclosure Information
It is well known to incorporate jounce bumpers in the design of motor vehicles to limit the upward travel of suspension components beyond a predetermined limit. Commonly, an elastomeric body is located either on the structure of the vehicle or on a suspension member, in a position allowing it to impact either a suspension member or the structure of the vehicle in the latter case. Referring to FIG. 2, an elastomeric body (not shown) would be rigidly secured to a frame member (not shown) in a position above a cantilevered arm 1 mounted on an axle housing 3. Alternatively, some vehicles allow the elastomeric body to impact directly with the axle housing, a leaf spring 5 or a suspension arm in those suspensions having coil springs and suspension arms.
The cantilevered arms of the type shown are metal castings and generally are quite heavy. Additionally, due to the strength requirements necessitated by the cantilevered design, they incorporate substantial material and weight so as to withstand the moments created by repeated impacts with the jounce bumper.
For these reasons, it would be desirable to provide a jounce stop apparatus that addresses the shortcomings of the type employing cantilevered arm designs.

Jounce stop apparatus for use in a vehicle suspension


With conventional print and electronic tools, researching statutory material is difficult and time-consuming. So, to facilitate this type of research, the present inventors devised systems, methods, and software that promise to improve the ability of researchers to find, verify, read, and/or interpret statutory information. One exemplary system provides options for users to access statutory information by citation, by table of contents, by index, and/or by popular name; presents specific statutory information in combination with visual indicators, such as red or yellow flags, that indicate the validity or status of the information; and provides requested statutory information in context of links to related information, such as tables of contents, other versions of a statute, case law, scholarly materials, legislative history, cross-referenced statutes, and administrative-law materials.

The American legal system relies heavily on written laws and judicial opinions. Because of this, judges and lawyers within our legal system are continually researching an ever-changing body of statutes and past opinions (case law) to make decisions and advise their clients.
To facilitate these searches, companies, such as West Publishing Company of St. Paul, Minn. (doing business as Thomson West), collect and publish statutes and judicial opinions from across the United States in both print and electronic form. The electronic form of the statutes and case law are electronically searchable via the Internet through the www.Westlaw.com legal research website.
Although services, such as Westlaw.com, have provided enormous benefits to the legal industry, the present inventors have recognized considerable room for improvement, particularly in the area of statutes research. This aspect of legal research is notoriously difficult and time-consuming. Even with electronic search capabilities, many researchers prefer using print materials.
Accordingly, the present inventors have recognized a need for tools that facilitate researching statutory information.

Systems, methods, and software for researching statutory information


An upper-body garment has an invertable pocket in the garment's back, formed between an exterior layer and an interior lining layer of the back panel. A vertical pocket opening on one side of the back panel permits ready access to the pocket while wearing the garment. Shoulder straps and pockets are formed within the invertable pocket. The pocket linings and straps may be drawn out to invert the pocket into a backpack configuration. The remainder of the garment may be entirely placed in the backpack and carried therein.

1. Field of the Invention
The present invention relates generally to upper body garments such as coats, jackets, sweaters, sweat shirts and the like, and means for conveniently carrying the garment on-body when not in use. More particularly, the invention pertains to a garment convertible into a backpack which contains the garment, and methods for making same.
2. State of the Art
The usefulness of backpacks for carrying heavy and/or bulky items on the back has long been recognized. A plethora of backpack designs is commercially available. Such backpacks may be as simple as the well-known Duluth backpack which comprises a deep woven basket with shoulder straps, or may be complex with a rigid frame, fabric container attachable to the frame and having numerous pockets, a myriad of adjustment straps, waist-strap and shoulder straps. Such backpacks are complex, relatively heavy, and time-consuming to fabricate. They are generally not suitable for day-hiking and the like.
Backpacks of limited capacity have been proposed. For example, in U.S. Pat. No. 5,987,644 to Mengato, a fabric backpack is shown which is attached at its periphery to the back panel of an athletic shirt. A horizontal zippered opening at the top of the backpack provides access to the backpack. No straps are provided, so the combination can be used as a backpack only by wearing the garment.
A common experience of hikers, bikers, golfers, boaters, anglers, hunters, campers, climbers and other outdoorsmen and outdoorswomen is the normal changeability of weather conditions. As a result of changes in temperature, wind speed, cloudiness, and precipitation, a person may need to add or remove outer clothing to remain comfortable. Changes in outer dress may also be necessitated by changing levels of personal exertion, health considerations and the like. The concept of "layering" is well-known as a means to be comfortable in spite of changing weather conditions, personal exertion, and other factors.
Where circumstances make removal of an outer garment desirable, means for carrying the garment in a small package is advantageous. Various devices for carrying a garment have been proposed in the prior art. An example of such an apparatus is found in U.S. Pat. No. 6,564,388 to Poston, wherein the garment is configured to be folded into a carry bag which may be hand-carried or, alternatively be located within a separate pack which is placed within the inside front of the garment. The design requires carrying of the separate pack in the front of one's person, which is very uncomfortable, and/or hand-carrying of the bag, which will occupy one of the person's hands. This is very inconvenient, inasmuch as people who are engaged in hiking, climbing, skiing, fishing, hunting, shopping, or other common outdoor activities will not want to have only one hand available for these activities.
Another type of garment carrying container is found in U.S. Pat. No. 4,689,831 to Greenberger et al., in which a backpack with shoulder straps is attachable to the outer back panel of a jacket. The jacket may be folded and placed in the backpack, and the straps used to carry the backpack. When worn as a jacket, the backpack portion is always a conspicuous "hump" on the back of the wearer.
In U.S. Pat. No. 2,825,902 to Breier, a jacket is shown in which a pocket is formed between the arm holes and neck i.e. the two-ply yoke area by sewing a generally triangular panel to the exposed surface of the inside jacket lining. A zipper located at the bottom of the pocket provides access thereto from within the jacket. The zipper is inaccessible when the jacket is worn. The jacket can be folded into the pocket to form a closed carrying case for hand carrying.
In U.S. Pat. No. 4,483,469 to Arisland, a vest is shown which is foldable into two separate attached containers which are joinable into a purse.
U.S. Pat. No. 5,123,117 to Prendergast depicts a reversible jacket in which a backpack is attached to the outer surface of the jacket back. When the jacket is reversed, the backpack is hidden within the jacket. The jacket may be folded against the backside of the backpack and covered by a flap normally rolled up at the bottom of the backpack.
In U.S. Pat. No. 4,404,687 to Hager, a pullover jacket is configured to collapse into a handbag for carrying. The empty handbag is attached to the inner front of the jacket, and includes strap handles.
U.S. Pat. No. 2,058,474 of Long describes a garment with an integral carrying bag with two handles, mounted on the interior of the back panel of a garment. Matching zipper strips surround the bag opening. This arrangement has a definite disadvantage in that the sharp exposed (i.e. open) zippers tend to catch and tear garments worn beneath the outer garment. A similar construction is shown in U.S. Pat. No. 2,146,243 to Aug.
U.S. Pat. No. 2,292,347 to Bailey shows a garment having a hanging panel attached to the inside back of a garment by a central horizontal sew-line. The panel has opposed matching zippers at the top and bottom edges. The garment may be folded up against the hanging panel and the zippers closed to enclose the garment. The hanging panel with exposed zippers is seen to be uncomfortable, and it is well known that free (unclosed) zippers tend to catch on fabric which they touch.
In U.S. Pat. No. 2,324,722 to Papierniak, a jacket is shown having a front pocket within which is attached a lined tab with buttonholes. Matching buttons are attached within the pocket. When the tab is pulled from the pocket and the garment carefully folded about the exterior of the pocket, the pocket may be inverted about the jacket to form a package.
U.S. Pat. No. 4,502,155 to Itoi describes outerwear having a complex structure for enclosing the outerwear in a backpack. The backpack is formed of two layers sewn along the upper edge to the back of a garment and held by "engaging members" such as snaps at the bottom corners. Thus, the backpack hangs generally loosely from the jacket back. The backpack has multiple zippers, chuck webs, engaging members and connectors. Shoulder straps are attached to the inside surface of the jacket back.
Another complex backpack design in the prior art is found in U.S. Pat. No. 4,476,587 to Itoi. The jacket is bisected transversely by front and back zippers. When these zippers are opened, the jacket is divided into a top portion and a bottom portion. The front and back zippers may then be joined to form an upside down bag. The bag may be pulled closed by strings sewn into the bottom edge of the jacket, and the exposed strings used to carry the bag.
Each of the above-described prior art references has disadvantages in complexity of construction with concomitant high cost, inconvenience in use, poor appearance, and/or lack of achieving the desired goals. The use of horizontally oriented zippers for supporting garment carrying containers leads to detachment of the zipper rails because of cross forces exerted on the zipper joint. None of the prior art references describes a conventional-appearing garment which has a hidden backpack construction not visible in its general appearance when worn.