An (Al,Ga,In)P semiconductor laser device has an optical region disposed between n-type and p-type cladding layers. An active region containing quantum well active layers and barrier layers disposed alternately with the quantum well layers is provided within the optical guiding region. Strained layers of InxGalxe2x88x92xP are used as the barrier layers. The active region is thus aluminium-free, and this reduces the oxygen impurity concentration in the active region thereby improving the performance and reliability of the laser. An aluminium-free spacer layer can be provided between one of the cladding layers and the quantum well active layer disposed closest to that cladding layer. The invention may be applied to other semiconductor devices, for example such as an LED.

1. Field of the Invention
This invention relates to a semiconductor device and particularly, but not exclusively, to a semiconductor device that emits visible radiation in the wavelength range 630 nm to 680 nm, such as a semiconductor laser device or light-emitting diode. The device may be of the edge-emitting or of the surface-emitting type.
2. Description of the Related Art
Laser devices or laser diodes (LDs) fabricated in the (Al,Ga,In)P material system which emit visible light in the 630 nm-680 nm wavelength range are becoming increasingly important components of professional and consumer products. For example, it is envisaged that the Digital Video Disc (DVD) system will employ a 635 nm-650 nm wavelength LD capable of delivering up to 30 mW output power up to a temperature of 60xc2x0 C. The next generation of semiconductor lasers will need an even greater maximum power output up to a higher (eg. 70xc2x0 C.) operating temperature.
By the (Al,Ga,In)P system is meant the family of compounds having the general formula (AlxGalxe2x88x92x)lxe2x88x92yInyP, where both x and y are between 0 and 1. One particular advantage of this semiconductor system is that it is lattice-matched to a GaAs substrate when the indium mole fraction, y, is equal to 0.48.
A principal limitation of current (Al,Ga,In)P laser diodes is that they are incapable of operating for long periods (or with a sufficiently low threshold current) at the highest specified operating temperature. It is generally believed that this in caused by electron leakage from the active region of the device into the surrounding optical guiding region and subsequently into the p-type cladding region.
The generic structure of a separate confinement laser structure intended to generate light at 630-680 nm will now be described with reference to FIGS. 1(a), 1(b) and 1(c).
FIG. 1(a) is a schematic band structure of a separate confinement laser structure fabricated in the (Al,Ga,In)P system. It consists of an n-doped (Al0.7Ga0.3)0.52In0.48P cladding region 1, an (Al0.5Ga0.5)0.52In0.48P optical guiding region 2, 4, a GaInP quantum well active region 3 disposed within the (Al0.5Ga0.5)0.52In0.48P optical guiding region, and a p-doped (Al0.7Ga0.3)0.52In0.48P cladding region 5. A p-type contact layer (not shown in FIG. 1(a)) may be provided on the p-type cladding region 5, and an n-type contact layer (not shown) may be provided on the n-type cladding region 1. Optical transitions giving rise to laser action in the quantum well active region 3 of the laser diode originate from electrons in the xcex93-band in the GaInP quantum well active region.
The terms xcex93-band and X-band as used herein refer to symmetry points in the Brillouin zone and are standard terms in solid state physics, see for example R. A. Smith xe2x80x9cSemiconductorsxe2x80x9d, (Cambridge University Press, 1978). The terms xcex93-minimum and X-minimum refer to the minimum energy level of the xcex93-band and the X-band, respectively.
The minimum energy in the conduction band of (Al,Ga,In)P is a function of the aluminium content. There is a crossover from a xcex93-band minimum to an X-band minimum at an aluminium concentration of about 0.55.
The aluminium mole fraction of the cladding regions 1, 5 need not be 0.7, provided that it is sufficient to provide an effective potential barrier to confine xcex93-electrons in the optical guiding region. FIG. 1(b) illustrates a similar laser structure to that of FIG. 1(a), but the cladding regions 1, 5 are formed of AlInP rather than (Al0.7Ga0.3)0.52In0.48P in order to increase the potential barrier confining xcex93-electrons in the optical guiding region 2, 4.
In the laser structures shown in FIGS. 1(a) and 1(b) the active region 3 is a single GaInP quantum well layer. It is alternatively possible for the active region to contain two or more quantum well layers separated by barrier layers.
FIG. 1(c) shows the xcex93-conduction band and valence band of a (Al,Ga,In)P laser device in which the active region comprises a plurality of quantum well layers. In the embodiment shown in FIG. 1(c), the active region 3 comprises three GaInP quantum well layers 3a with each neighbouring pair of quantum well layers being separated by a barrier layer 3b. The barrier layers 3b are formed of a material having a higher xcex93-band than the material used to form the quantum well layers 3a, such as (Al0.3Ga0.7)0.52In0.48P or (Al0.5Ga0.5)0.52In0.48P. In the laser shown in FIG. 1(c) the barrier layers 3b are formed of (Al0.5Ga0.5)0.52In0.48P, the same material as used for the optical guiding region 2, 4.
Degradation of semiconductor lasers has been a major problem in developing commercial devices. AlGaAs/GaAs lasers having a lasing wavelength of around 0.85 xcexcm were initially developed in the 1970s, but early examples of these lasers degraded quickly during use and, as a result, had a low lifetime and were unsuitable for commercial applications. It took a considerable time to overcome the significant degradation problems involved with these lasers, but long lifetime AlGaAs/GaAs lasers are now commercially available. M. Fukuda reports, in xe2x80x9cReliability and Degradation of Semiconductor Lasers and LEDEsxe2x80x9d ISBN 0-89006-465-2, that AlGaAs/GaAs lasers having a life time greater than 10,000 hours are now commercially available.
In order for (Al,Ga,In)P lasers to be commercially successful, these lasers must have a life time comparable with that of AlGaAs/GaAs lasers.
At present, wide band-gap phosphide lasers operating in the visible spectrum at a wavelength of about 650 nm display a severe degradation problem. Although the lifetime of low power phosphide lasers is approximately 10,000 hours which is satisfactory for commercial purposes, a typical lifetime of a high-power phosphide laser is only about 5,000 hours which is not commercially acceptable. Furthermore, it is necessary to anneal the lasers in order to obtain these lifetimes, and lasers that are not annealed have much shorter lifetimes.
The degradation problem is particularly serious for lasers fabricated using molecular beam epitaxy (MBE). At present, phosphide laser structures that are grown by MBE have to be thermally annealed in order to improve their reliability and to decrease the threshold for laser operation. It Is presumed that the annealing process removes (or at least moves) some of the non-radiative recombination centres in the material. It is, however, undesirable to carry out an annealing step. One common p-type dopant for the p-type cladding region is beryllium, and if a beryllium-doped laser device is annealed beryllium can diffuse from the p-type cladding region into the active region. Such diffusion will degrade the performance of the laser device, and may also lower the yield of the manufacturing process.
One possible reason for the degradation of phosphide lasers is that the degradation is due to oxygen contamination of the active region. Oxygen contamination of aluminium-containing phosphide materials can easily occur, owing to the high reactivity of aluminium with oxygen. Oxygen introduces non-radiative defects into the active layer, and this may give rise to a high threshold for laser oscillation.
Oxygen is a common contaminant in aluminium-containing alloys, because of the high reactivity of aluminium with oxygen-containing species. In the growth of AlGaAs/GaAs semiconductor structures, it is known that oxygen atoms are sufficiently mobile during the epitaxial growth process for them to migrate to the interface and to become trapped at the interface. Oxygen forms non-radiative centres in GaAs and in AlGaAs, and so the presence of oxygen tends to reduce the performance and reliability of AlGaAs/GaAs lasers. N. Chand et al. report, in xe2x80x9cJ. Vac. Sci Technol. Bxe2x80x9d Vol. 10 (2), p807, 1992, that an AlGaAs layer having an aluminium mole fraction of 0.3 or greater has a typical oxygen atom density of at least 1017 cmxe2x88x922. In contrast, in GaAs the oxygen concentration is typically too small to detect.
Chand et al. show that oxygen tends to accumulate at the AlGaAa/GaAs interface, so giving rise to an xe2x80x9coxygen spikexe2x80x9d in the active region of the device. They also show that a beryllium-doped cladding layer has a greater oxygen concentration than a silicon-doped cladding region.
FIG. 3(a) shows the oxygen concentration of the laser of FIG. 1(c). The band structure of the laser is repeated in FIG. 3(b), so that the oxygen concentration can conveniently be related to the layers of the device.
The laser of FIG. 1(a) consists mainly of (Al,Ga,In)P with a non-zero aluminium content, so that its background oxygen concentration is expected to be approximately 1017 cmxe2x88x923. In the growth of this structure, oxygen migrates to the interfaces between the quaternary layers and the GaInP quantum well layers 3a. This gives rise to a localised high oxygen concentration, or xe2x80x9cspikexe2x80x9d, in the regions of each interface. These spikes in the oxygen concentration increase the oxygen concentration in the active layers, and lead to the formation of non-radiative traps in the quantum well active layers. These traps degrade the performance and reliability of the laser, as discussed above.
FIG. 4 shows the oxygen concentration for a conventional laser structure fabricated in the (Al,Ga,In)P system. The oxygen concentration was measured by secondary ion mass spectrometry (SIMS). FIG. 4 shows the results of two measurements, carried out at different scanning rates.
The sample measured has an active region containing 3 GaInP quantum well layers sandwiched between (Al0.5Ga0.5)0.52In0.48P barrier layers, an (Al0.5Ga0.5)0.52In0.48P waveguiding region, and an (Al0.7Ga0.3)0.52In0.48P cladding region. The cladding region and the waveguiding region each have an oxygen concentration measured by SIMS of around 1017 cmxe2x88x923, compared to an oxygen concentration as low as 1015 cmxe2x88x923 in the GaInP quantum well layers (which are aluminium-free). There is therefore a sharp spike in the oxygen concentration at each interface between a barrier layer and a quantum well layer (in a similar manner to the case of GaAlAs/GaAs). The SIMS instrument cannot resolve such sharp features, so that FIG. 4 in fact shows a convolution of the oxygen level across the three quantum well layers. The single observed spike in the oxygen concentration is an artefact of the measurement technique.
The (Al0.7Ga0.5)0.52In0.48P cladding layer and the (Al0.5 Ga0.5)0.52In0.48P optical guiding regions are measured as having oxygen concentrations of around 1017 cmxe2x88x923. The oxygen concentration in the active region is significantly greater than this. (As noted above, the single oxygen spike of FIG. 4 is an artefact of the measurement technique.)
The region at a depth of 2.6-2.8 xcexcm is a GaInP layer which, as anticipated, is observed as having a low oxygen concentration. The oxygen spike that occurs at a depth of 2.8-3.0 xcexcm is at the interface between the epilayer structure and the substrate, and is due to oxygen not having been completely removed from the substrate before the epitaxial growth process.
There have been a number of attempts to produce semiconductor laser devices having an aluminium-free active region. A. Al-Muhanna et al. have proposed, in xe2x80x9cApplied Physics Lettersxe2x80x9d Vol. 72, No. 6, pages 641-642 (1998), a laser device in the InGaAlP system with an InGaAsP active layer. This laser emits light having a wavelength of 730 nm. they report that this laser has an improved efficiency, and they attribute this to the use of an aluminium-free active region.
Wade et al. report, in xe2x80x9cApplied Physics Lettersxe2x80x9d Vol. 70, No. 2, pages 149-151 (1997), a laser emitting light at 830 nm and having an aluminium-free active region. This device again uses an InGaAsP layer as the active region, and this is disposed in an InGaP optical guiding region. Wade et al. report an improvement in the reliability of the laser, which is attributed to the use of an aluminium-free active region. They also report an improved COD (catastrophic optical mirror damage) power density level.
However, the approach of using a InGaAsP active layer cannot be used to obtain a laser device emitting light in the wavelength range 630 nm to 680 nm, because the band gap of InGaAsP is too small to produce emission in this wavelength range. This is the case for all III-V semiconductors (with the exception of the nitrides).
EP-A-0 476 689 discloses a laser device emitting in the 630-680 nm range in which the active region is formed of strained AlGaInP layers. The barrier layers are under tensile strain and the quantum well layers are under compressive strain and the different strains induce different band structures in the barrier and quantum well layers. This document also suggests that a similar approach could be used with an active region formed of strained GaInP layers, although the absence of aluminium would increase the emission wavelength of the laser.
The lasers suggested in EP-A-0 476 689 have an AlGaInP waveguide adjacent to the active region. Oxygen contamination will occur in the waveguide since it contains aluminium, and a spike in the oxygen concentration will occur at the interface between the active region and the waveguide.
U.S. Pat. No. 5,331,656 discloses a GaInP laser that emits in the 550-590 nm wavelength range. The active region contains quantum well layers and barrier layers both formed of GaInP doped with nitrogen. However, doping with nitrogen is difficult to carry out in practice. Moreover slight doping with nitrogen will not significantly change the alloy composition and so will not cause significant strain, whereas heavy doping with nitrogen will significantly reduce the bandgap.
Lasers having an active region in which the quantum well layers and barrier layers are oppositely strained are also disclosed in U.S. Pat. No. 5,903,587, JP-A-11 145 549 and U.S. Pat. No. 5,841,152. However, these documents do not relate to an (Al,Ga,In)P laser emitting in the 630-680 nm wavelength range. JP-11 145 549 discloses an MQW layer in which the quantum well layers and the barrier layers are both InGaAsP layers. The laser disclosed in U.S. Pat. No. 5,903,587 emits in the 0.98 to 1.02 xcexcm range and has an active region containing barrier layers formed of GaAsP and quantum well layers formed of GaInAs. U.S. Pat. No. 5,841,852 discloses a laser emitting light having a wavelength of 1.3 xcexcm, in which the barrier layers are InGaAsP, and the quantum well layers are InGaAs.
A first aspect of the present invention provides a semiconductor device having an aluminium-free active region, the active layer comprising one or more quantum well layers and one or more barrier layers, the quantum well layer and the barrier layer being disposed alternately; wherein the or each barrier layer is a strained layer; and wherein the device further comprises a first cladding layer and an aluminium-free layer disposed between the first cladding layer and the quantum well layer closest to the first cladding layer.
The term xe2x80x9caluninlum-free layerxe2x80x9d as used herein refers to a layer that does not have aluminium as an intentional constituent.
Straining a layer of semiconductor material can increase the band-gap of the material. The use of a strained layer for the barrier layer(s) provides a barrier layer or layers having the necessary xcex93-band energy to provide an effective barrier to the transport of xcex93-electrons between neighbouring quantum well layers without the need to intentionally introduce aluminium into the barrier layer(s). The invention thus makes possible a device having an aluminium-free active region.
Moreover, oxygen is likely to accumulate at the interface with the first cladding layer during the growth process, leading to a region of high oxygen concentration. Providing an aluminium-free layer between the first cladding layer and the quantum well layer closest to the first cladding layer spaces the active region from this region of high oxygen concentration, and reduces the effect of the region of high oxygen concentration on the operating properties of the device.
A second aspect of the present invention provides a semiconductor device having an aluminium-free active region, the active layer comprising one or more quantum well layers and one or more barrier layers, the quantum well layer and the barrier layer being disposed alternately; wherein the or each barrier layer is a strained layer; and wherein the device emits, in use, light having a wavelength in the range 630 to 680 nm.
As noted above, the use of a strained layer for the barrier layer(s) avoids the need to intentionally introduce aluminium into the barrier layer(s). The invention thus makes possible a device having an aluminium-free active region and that can emit light in the 630-680 nm wavelength range of the visible spectrum. By avoiding the need to introduce aluminium into the active region of, for example, a laser device, degradation of the device owing to oxygen contamination of the active region is reduced and the lifetime of the device is consequently increased.
A device according to the second aspect of the invention may further comprise: a first cladding layer; and an aluminium-free spacer layer disposed between the first cladding layer and the quantum well layer closest to the first cladding layer.
A device according to the first aspect of the invention may emit, in use, light having a wavelength in the range 630-680 nm.
A device according to either aspect of the invention may emit, in use, light having a wavelength in the range 635-630 nm.
The or each barrier layer maybe a tensile strained layer.
The lattice mismatch between the or each barrier layer and the or each quantum well layer may be small. This increases the critical thickness of the barrier layer(s).
The or each quantum well layer may be lattice matched to the cladding layer(s). Alternatively, the or each quantum well layer may be a compressive strained layer. This allows a device with a strain compensated active region to be produced, by using a compressive strained layer for the or each quantum well layer and a tensile strained layer for the or each barrier layer.
The or each barrier layer may contain indium. Introducing indium into the barrier layer(s) reduces the strain in the barrier layer(s) and so increases the critical thickness of the barrier layer(s).
The aluminium-free layer may be a strained layer.
The device may be fabricated in the (Al,Ga,In)P material system. This allows for example a device emitting light in the region 630-680 nm and having an aluminium-free active layer to be produced.
The or each active layer may be a GaxInlxe2x88x92xP layer and the or each barrier layer may be a GayInlxe2x88x92yP layer, where y greater than x. For example, the or each active layer may be a Ga0.52In0.48P layer and the or each barrier layer may be a Ga0.61In0.39P layer, or alternatively the or each active layer may be a Ga0.52In0.48P layer and the or each barrier layer may be a Ga0.71In0.29P layer. Tensile strained layers of Ga0.61In0.39P and Ga0.71In0.29P have approximately the same band-gap as (Al0.3Ga0.7)0.52In0.48P and (Al0.5Ga0.5)0.52In0.48P respectively, and so can be used to replace these materials without significantly affecting the band-gap profile.
Alternatively, the or each active layer may be a Ga0.43In0.57P layer. This material has a smaller lattice constant that GaAs, and so will form a compressive strained layer when grown on a layer that to lattice matched to GaAs.
The device may be a laser device. Alternatively, the device may be a light-emitting diode.


The relaxation oscillator includes a comparator and a latch. The comparator includes a comparator output and a comparator input that is configured to receive a first input signal in response to a first signal and configured to receive a second input signal in response to a second signal. The latch includes a latch-set input that is configured to be coupled to the comparator output in response to a third signal, a latch-reset input that is configured to be coupled to the comparator output in response to a fourth signal and a latch output that is configured to output the second signal. The relaxation oscillator is configured to achieve an approximately fifty percent duty cycle without requiring the use of a second comparator.

With the spectacular rise of personal computer and telecommunications technology, there has been an equally phenomenal development in the technology of ICs. In particular, with the drive to ever higher levels of circuit integration, the importance of conserving the real estate on a die and minimizing the consumption of power continues to draw the attention of scientists and engineers engaged in the design of ICs.
This is particularly true in the field of capacitance-sensing devices where there is a premium attached to producing devices with small size and minimal power consumption. The elimination of circuit designs which are overdesigned and suffer from inelegant use of the die real estate for integrated circuits used to drive capacitance-sensing devices is an area drawing the continued attention of scientists and engineers engaged in the development of capacitance-sensing devices. Thus, elegant circuit designs that reduce the number of circuit components on a die of an IC and minimize power consumption are of particular interest for maintaining a competitive edge in the field of capacitance-sensing devices and integrated-circuit technology, more generally.


In an example, an electronic device may include a housing and a first acoustic device pivotally disposed in the housing. The first acoustic device may move between a first position within the housing and a second position outside the housing. The first acoustic device may direct an acoustic signal in a direction. Further, the electronic device may include a camera to capture an image of an area in front of the electronic device. Furthermore, the electronic device may include a processor operatively coupled to the camera and the first acoustic device. The processor may determine a location of a facial feature of an operator using the captured image. Further, the processor may control an angle of rotation of the first acoustic device relative to the housing based on the location of the facial feature to modify the direction of the acoustic signal.

The emergence and popularity of mobile computing has made portable electronic devices, due to their compact design and light weight, a staple in today's marketplace. An example electronic device may include a notebook computer, a tablet computer, a convertible device, and the like. Due in part to their mobile nature, such electronic devices may often be provided with a speaker disposed within a housing of the electronic devices and include multiple sound emission holes defined in the housing for outputting sound produced by the speaker.

HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.


An electrophoretic display apparatus includes a bottom substrate, an electrophoretic layer, a color filter substrate and a spacing layer. The bottom substrate has a drive circuitry layer, and the electrophoretic layer is disposed on the drive circuitry layer of the bottom substrate. The color filter substrate is disposed above the electrophoretic layer, and the spacing layer is disposed between the color filter substrate and the electrophoretic layer. The electrophoretic display apparatus has better display quality.

1. Fields of the Invention
The present invention relates to a display apparatus, and particularly to an electrophoretic display apparatus.
2. Description of the Related Art
With the advancement of the flat display technology and due to the flat display apparatuses having advantages of light in weight, small in size and low power consuming, the flat display apparatuses have become more and more popular. In general, the flat display apparatuses include liquid crystal display (LCD) apparatuses, plasma display panel (PDP) apparatuses, organic light emitting diode (OLED) display apparatuses and electrophoretic display (EPD) apparatuses, etc., wherein the electrophoretic display apparatus does not include light emitting source, so the electrophoretic display apparatus further has the advantage of power saving in comparison with other flat display apparatuses.
The earlier electrophoretic display apparatus is a monochrome display apparatus, but to improve a market competitiveness of the electrophoretic display apparatus, a color filter substrate is used in conventional technique to enable the electrophoretic display apparatus to display color images. It's only in this way that the electrophoretic display apparatus can achieve color display capability.
FIG. 1 is a schematic view of a conventional electrophoretic display apparatus. Referring to FIG. 1, the conventional electrophoretic display apparatus 100 includes a bottom substrate 110, a front plane laminate 120 and a color filter substrate 130. The bottom substrate 110 has a drive circuitry layer 112, the front plane laminate 120 is disposed on the drive circuitry layer 112, and the color filter substrate 130 is disposed on the front plane laminate 120. Moreover, the drive circuitry layer 112 includes a plurality of pixel electrodes (not shown in FIG. 1). The front plane laminate 120 includes an electrophoretic layer 122 and a transparent electrode layer 124 disposed on the electrophoretic layer 122. The electrophoretic layer 122 includes a plurality of black charged particles 123b and a plurality of white charged particles 123w, wherein the black charged particles 123b and the white charged particles 123w have different electrical properties. The white charged particles 123w and the black charged particles 123b in the electrophoretic layer 122 are driven toward different directions by changing electrical fields between the pixel electrodes and the transparent electrode layer 124, and such that the electrophoretic display apparatus 100 is capable of displaying different images.
Furthermore, the color filter substrate 130 includes a plurality of red photoresists 132r, a plurality of green photoresists 132g and a plurality of blue photoresists 132b, and the photoresists 132r, 132b and 132g are separated by a black matrix 134. The red photoresist 132r, the green photoresist 132g and the blue photoresist 132b are respectively used to filter white light into red light, green light and blue light so as to enable the electrophoretic display apparatus 100 to display color images.
The color filter substrate 130 disposed on the front plane laminate 120 enables the electrophoretic display apparatus 100 to display color images. However, due to the front plane laminate 120 and the color filter substrate 130 being rigid substrates, air bubbles are easily produced during assembling the color filter substrate 130 with the front plane laminate 120. The air bubbles result in gaps existed between the front plane laminate 120 and the color filter substrate 130, so the color filter substrate 130 can not be flatly attached to the front plane laminate 120. Therefore, the display quality, or the yield, of the conventional electrophoretic display apparatus 100 is reduced.


A pilot channel transmission method is provided of transmitting a pilot channel through a downlink from a base station in a CDMA mobile communication system including base stations. Each base station is installed in one of a plurality of cells, uses a same frequency, and divides its channels using orthogonal codes uniquely assigned to the channels. Each of the cells is identified by multiplying a spreading code assigned to each base station by the channels spread by the orthogonal codes. In the pilot channel transmission method, when a plurality of orthogonal code sets, each of which includes a plurality of spreading codes assigned thereto, using by each base station, a pilot channel is assigned to each orthogonal code set, and at least one of the pilot channels is transmitted. The pilot channel can be provided with a symbol rate higher than the minimum symbol rate defined in the system.

1. Field of the Invention
The present invention relates to a CDMA (Code Division Multiple Access) transmission method of downlink pilot channel in a CDMA mobile communication system, a CDMA mobile communication system, a base station and a mobile station.
2. Description of Related Art
FIG. 1 is a schematic diagram illustrating a spreading code arrangement in a CDMA mobile communication system.
As illustrated in FIG. 1, cell division is usually implemented by spreading codes with a long period (called "scrambling codes" from now on) that are uniquely assigned to cells each, and channel division is implemented by spreading codes with a short period (called "channelization codes" from now on) that are uniquely assigned to channels in the cells each.
Although the channelization codes usually consist of codes orthogonal to each other, the number of such codes is limited, and hence, a shortage of the channelization codes can take place. In such a case, that is, when a set of orthogonal codes is exhausted, a new channelization code set is generated by assigning a plurality of scrambling codes to each cell. This will be described with reference to FIG. 1. In cell #1, although the channelization code set #1 corresponding to channels CH#1+#N employs a scrambling code SCCODE #1, the channels CH#N+1 and onward use a scrambling code SCCODE #2 to create a new channelization code set #2.
Next, referring to FIGS. 2 and 3, an arrangement of downlink pilot channels and an example of transmission power of each channel in a conventional technique will be outlined.
FIG. 2 is a diagram illustrating an arrangement of the downlink pilot channels on the conventional technique. In FIG. 2, the height of each channel schematically represents the symbol rate of the channel, which means that a thicker channel has a higher symbol rate. The CDMA mobile communication system carries out orthogonalization by spreading data symbols of various channels using the channelization codes to transmit these channels at the same transmission rate. Here, the same transmission rate after the spreading is referred to as "chip rate", and the transmission rate of the data symbols before the spreading is referred to as "symbol rate". Generally, a system with a chip rate of N chips/second can contain the orthogonal code set of the cells in a single sequence if the total symbol rate of the channels is equal to or less than N.
The downlink pilot channel CH#1 is provided for the purpose of obtaining phase information used for demodulating the downlink traffic channels, detecting a received path, and obtaining interference power for traffic channels to carry out the transmission power control. The pilot channel has the minimum symbol rate provided by the system (the CH 1 is denoted as a thinnest channel in FIG. 2) because it either undergoes data modulation by a known pattern or does not undergo any data modulation at all.
FIG. 3 is a diagram illustrating transmission powers of downlink channels in the conventional technique. In FIG. 3, the height of each channel schematically denotes the transmission power of the channel. Thus, a higher channel has higher transmission power. Since the pilot channel CH#1 is utilized for the purposes mentioned above, it is usually transmitted at the transmission power higher than the transmission power of the other traffic channels as illustrated in FIG. 3.
To achieve interference power measurement for the transmission power control at high accuracy, it is necessary to generate many samples of a signal used for the measurement. However, since the conventional pilot channel is provided with the minimum symbol rate of the system, it is impossible to obtain sufficient samples, presenting a problem of hindering high measuring accuracy.
In addition, when using a plurality of orthogonal code sets in the downlink, although the channels belonging to the same orthogonal code set do not interfere with one another on the same received paths, they can interfere on the other paths. On the other hand, channels belonging to different orthogonal code sets can interfere to each other regardless of whether on the same paths or the other paths. Accordingly, the interference power received by the traffic channels differ depending on the orthogonal code sets to which the traffic channels belong. However, since the pilot channel is provided for only one orthogonal code set as illustrated in FIG. 2, there arises a problem in that the channels in the other orthogonal code sets prevent accurate interference power measurement for the transmission power control.
Moreover, since the pilot channel is an overhead channel without transmitting any information, transmitting it beyond necessary transmission power will bear upon the other channels, presenting a problem of reducing channel capacity. On the other hand, the interference power measurement can be achieved even if the transmission power is zero by measuring the variance of the channel, and when using the pilot channel for the purposes other than the interference power measurement, it usually does not matter whether it belongs to the same orthogonal code set or not.

Transmission method of downlink pilot channel in CDMA mobile communication system, and CDMA mobile communication system


A display device includes the following elements. A display has a display area and includes an electro-optic layer and a light-reflecting layer reflecting light emitted from the electro-optic layer to the viewing side of the display device, the light-reflecting layer being arranged in the display area. A plate-shaped exterior has a frame area including a portion located outside the periphery of the display. An antireflective plate continuously covers both of the display area and the frame area. The antireflective plate prevents external light, which enters the viewing side of the display device and is reflected by the light-reflecting layer or the frame area, from emerging on the viewing side.

1. Technical Field
The present invention relates to a technique for displaying an image using an electro-optic layer, such as a luminous layer or a liquid crystal layer.
2. Related Art
A display, in which light reflected by a reflecting layer disposed on the rear surface of an electro-optic layer is allowed to emerge on the front (viewing) side of the display and is used for display, has disadvantages in that external light incident on the viewing side of the display is reflected toward the viewing side by the reflecting layer and a view in front of the display is superimposed on an image originally displayed on the display, i.e., the view in front of the display is reflected in the displayed image. Japanese Unexamined Patent Application Publication Nos. 8-321381 and 9-127885 disclose techniques for preventing a reflection of a view in front of a display using a circular polarizer arranged adjacent to the viewing side of the display above an electro-optic layer.


The avoidance of port collisions in a hardware-accelerated network protocol, such as Transmission Control Protocol (TCP)/Internet Protocol (IP), is disclosed. In one example, a hardware-accelerated host bus adaptor (HBA) offloads protocol processing from a host computer's operating system. However, a port collision occurs if a non-accelerated host TCP/IP stack and a hardware accelerated host bus adapter TCP/IP stack choose the same port for establishing a network connection. In a double-ended TCP/IP acceleration connection, a unique TCP port is bound to the accelerated TCP/IP stack. In a single-ended TCP/IP acceleration connection, either the host TCP/IP stack is prevented from using that port or a non-accelerated connection is associated with an accelerated connection without binding a port.

Transmission Control Protocol (TCP)/Internet Protocol (IP) is a set of networking protocols that provide communication across interconnected networks, between computers with diverse hardware architectures and various operating systems. The TCP/IP protocols track Internet Protocol addresses of nodes, routes outgoing messages and recognizes incoming messages. TCP is a connection-oriented, end-to-end transport layer protocol used to transfer data in a network. Internet Protocol addresses packets and is the messenger protocol of the TCP/IP protocols.
A conventional network interface card (NIC) receives TCP/IP packets from a network and buffers the packets in a network interface card memory before transferring to a host operating system memory. A conventional host operating system (OS) copies packets from the host OS memory to application memory. The network interface card may also transfer TCP/IP packets from the host OS to the network.
A kernel of a conventional host operating system may have a TCP/IP stack that handles transport protocol processing of TCP/IP packets. The host TCP/IP stack may use TCP and Internet Protocol headers to determine a "connection" to which a packet is associated. An Internet Protocol header may include a source Internet Protocol address and a destination Internet Protocol address. A TCP header may include a source port ID/number, a destination port ID/number, a checksum, a packet sequence number and other control information. If the TCP/IP packets are received from the network out of order, the host operating system may use TCP packet sequence numbers in TCP headers to put the TCP/IP packets in a proper order. The host operating system may also reassemble data (messages) that the NIC receives in pieces.
Popular legacy communication libraries and technologies, such as sockets on TCP/IP Ethernet, rely on the host processor to process communication protocols. As processors and networks become faster, host computer systems spend more time running communication protocols, which leaves less time for application processing. As the host processor becomes over-taxed by the communications protocol processing overhead, the processor has less time to execute applications. The network may be underutilized, and network potential may remain unrealized.
The present application may refer to the following documents: "Virtual Interface Architecture Specification," Version 1.0, Dec. 16, 1997 from Compaq, Intel and Microsoft (hereinafter "VIAR"); "Intel Virtual Interface (VI) Architecture Developer's Guide," September, 1998 from Intel (hereinafter "VIDG"); "VIDF Virtual Interface (VI) Architecture Developer's Guide," Revision 1.1 Draft, Sep. 26, 2000 from Intel; and a "VI/TCP (Internet VI)" memo published by Jim Williams, a named inventor of the present application, and S. DiCecco, for the Network Working Group of the Internet Engineering Task Force (IETF), on Jul. 14, 2000 (hereinafter "IETF Memo").

Avoiding port collisions in hardware-accelerated network protocol

Emulex Design & Manufacturing Corporation


The invention relates to a method for forming a composition comprising a thermoplastic composite in the form of a linear profile extrudate. Such a profile comprises a structural member having improved tensile strength, flex modulus, impact resistance and other improved structural properties. The invention involves a unique extruder configuration having a change in direction for the resin and fiber that optimizes the composite strength by promoting the random orientation of the fibers resulting in improved structural properties. Further, because of the change in direction, the extruder can include a cooling feature that cools the profile interior as the profile leaves the exit die thus increasing the physical properties, productivity and quality of the product.

Conventional window and door manufacturers have commonly used wood and metal components in forming structural members. Commonly, residential windows are manufactured from milled wood products or extruded aluminum parts that are assembled with glass to form typically double hung or casement units. Wood windows while structurally sound, useful and well adapted for use in many residential installations, can deteriorate under certain circumstances. Wood windows also require painting and other periodic maintenance. Wooden windows also suffer from cost problems related to the availability of suitable wood for construction. Clear wood products are slowly becoming more scarce and are becoming more expensive as demand increases. While metal components are often combined with glass and formed into single unit sliding windows, metal windows typically suffer from substantial energy loss during temperature extremes of heat or cold.
Extruded thermoplastic materials have also been used as non-structural components in window and door manufacture. Filled and unfilled thermoplastics have been extruded into useful seals, trim, weather-stripping, coatings and other window construction components. Thermoplastic materials such as polyvinyl chloride have been combined with wood members in manufacturing PERMASHIELD.RTM. brand windows manufactured by Andersen Corporation for many years. The technology disclosed in Zanini, U.S. Pat. Nos. 2,926,729 and 3,432,883, have been utilized in the manufacturing of plastic coverings or envelopes on wooden or other structural members. Generally, the cladding or coating technology used in making PERMASHIELD.RTM. windows involves extruding a separate thin polyvinyl chloride outer layer or envelope surrounding a wooden structural member.
Polyvinyl chloride has been combined with wood fiber to make extruded materials. Such materials have successfully been used in the form of a structural member that is a direct replacement for wood. These extruded materials have sufficient modulus, compressive strength, coefficient of thermal expansion to match wood to produce a direct replacement material. Typical composite materials have achieved a modulus greater than about 500,000 psi (preferably between 600,000 and 1,500,000 psi) acceptable COOT, tensile strength, compressive strength, etc. to be useful. Deaner et al., U.S. Pat. Nos. 5,406,768, 5,441,801, 5,486,553, 5,497,594, 5,518,677, 5,539,027 and 5,695,874 and U.S. Ser. Nos. 08/543,959 (application pending, filed 17 Oct. 1995) and 08/587,828 (application abandoned) disclose a PVC/wood fiber composite that can be used as a high strength material in a structural member. This PVC/fiber composite has utility in many window and door applications.
A substantial and continuing need exists to provide a improved composite material that can be made of thermoplastic polymer and wood fiber. The composite can be made with an optional, intentional recycle of a waste stream. A further need exists for a composite material that can be extruded into a shape that is a direct substitute for the equivalent milled shape in a wooden or metal structural member. A thermoplastic with fiber compatibility, good thermal properties and good structural or mechanical properties is required. This need also requires a composite with a coefficient of thermal expansion that approximates wood, that can be extruded into reproducible stable dimensions, a high modulus, a high tensile strength, a high compressive strength, a low thermal transmission rate, an improved resistance to insect attack and rot while in use and a hardness and rigidity that permits sawing, milling, and fastening retention comparable to wood members. Still further need exists to optimize the structural properties of the material and to increase productivity without reducing composite structural properties.

Resin and wood fiber composite profile extrusion method


An illumination system is provided for combining two or more light sources. A plurality of light sources radiate random polarization light. A plurality of collecting light pipes corresponds to the plurality of light sources. Each collecting light pipe has an entrance end disposed towards the respective light source. The collecting light pipes are laterally offset and overlapping opposite their respective entrance ends. A combining light pipe is disposed perpendicular to the collecting light pipes. A polarizing beam splitter and a mirror are sequentially arranged in each collecting light pipe essentially opposite the entrance end directing a first polarization light and a second polarization light, respectively upwards towards the combining light pipe. The combining light pipe has an entrance end overlying the polarizing beam splitter and mirror of each collecting light pipe to collect and combine the light from each polarizing beam splitter and mirror.

In existing light projection systems there is typically a tradeoff between optimum brightness and lamp life. One approach to this problem is to provide a system with two lamps. However, when such systems which are adapted for use with microdisplays, there is not adequate means for uniform illumination and polarization recovery. These systems are also limited to two lamps, and require two relay lenses increasing cost and space requirements.

Multiple lamp illumination system with polarization recovery and integration


Provided is an oxide single crystal of large size having the crystal structure of Ca.sub.3 Ga.sub.2 Ge.sub.4 O.sub.14 and containing Ge as a constituent element and a method of manufacturing thereof. The oxide single crystal is obtained by a manufacturing method comprising the steps of preparing a melt of starting materials containing GeO.sub.2 and growing said oxide crystal from said melt of starting materials in single-crystal growing atmosphere, which is characterized in that said starting materials contain GeO.sub.2 in a stoichiometrically excess amount, and/or said single-crystal growing atmosphere is a gas having an oxygen partial pressure greater than about 2.times.10.sup.-1 atm.

1. Technical Field of the Invention
The present invention relates to an oxide single crystal and a method of manufacturing it. More particularly, the oxide single crystal has the crystal structure of Ca.sub.3 Ga.sub.2 Ge.sub.4 O.sub.14 and contains Ge as a constituent element and the method comprises the steps of preparing a melt of starting materials containing Ge, and growing said oxide crystal from said melt of starting materials in single-crystal growing atmosphere. The oxide single crystal is used as a material for piezoelectric devices (because of its piezoelectric properties) and a solid laser host material.
2. Related Art of the Invention
Since the discovery of Ca.sub.3 Ga.sub.2 Ge.sub.4 O.sub.14 compound by B. V. Mill et al., a number of compounds of the same structure have been found as the result of substitution of constituents with other cations. Examples are La.sub.3 Ga.sub.5 SiO.sub.14, La.sub.3 Ga.sub.5.5 Nb.sub.0.5 O.sub.14, La.sub.3 Ga.sub.5.5 Ta.sub.0.5 O.sub.14, and La.sub.3 Ga.sub.5 ZrO.sub.14 which are formed by substitution of Ca with La or substitution of Ge with Ga and Si, Ga and Nb, Ga and Ta, or Ga and Zr. They have been found to have electromechanical coupling coefficients greater than that of .alpha.-quartz. They have also been found to have a crystal axis along which the temperature coefficient of frequency is zero. For these reasons, they are regarded as a promising material for the piezoelectric devices of the next generation of mobile communications equipment. The technology in this field has advanced to such an extent that in a material without Ge, La.sub.3 Ga.sub.5 SiO.sub.14, a single crystal (an ingot having about 3 inches in diameter) can be produced easily by Czochralski method.
It is known that the La,Ga-based compound mentioned above is surpassed in electromechanical coupling coefficient by those Ca.sub.3 Ga.sub.2 Ge.sub.4 O.sub.14 compounds in which the Ca site is replaced by an alkali metal ion or alkaline earth metal ion. Nevertheless, these compounds are not yet available in the form of a large single crystal because of many difficulties involved. For example, they have a melting point of 1300.degree. C. or above which exceeds the vaporizing point of GeO.sub.2, one of the starting materials. This leads to a product of poor quality due to its composition differs from that of the starting materials, cracking in the crystal, and gaseous impurity phases.

Method of manufacturing oxide single crystal


Provided is an optical connection apparatus for a parallel optical interconnect module and a parallel optical interconnect module using the same for reducing a coupling loss generated due to an alignment error when coupled with an optical fiber, comprising: a 2D reflector in a prism shape and having at least two rows of cylinder type lens attached thereto; a 2D optical waveguide having at least two layers of core arrays; at least two rows of 2D optical benches; and a 2D ferrule capable of loading at least two layers of optical fibers so as to facilitate the fixing of the 2D optical waveguide for optical interconnection.

1. Field of the Invention
The present invention generally relates to a connection apparatus for a parallel optical interconnect module and a parallel optical interconnect module that an optical signal is transmitted or received through an optical fiber, and more particularly, to a connection apparatus for a parallel optical interconnect module and a parallel optical interconnect module, comprising a 2D reflector with a prism reflecting surface having at least two rows of cylinder type lenses so as to reduce a coupling loss generated from a misalignment when coupled with optical fiber, a 2D optical waveguide having at least two layers of core array, at least two rows of 2D silicon optical benches to reduce a coupling loss generated from a misalignment when coupled with optical fiber, a 2D ferrule for loading at least two layers of optical fibers to facilitate the fixing of the 2D optical waveguide for optical coupling.
2. Discussion of Related Art
Generally known in the art, in low-speed telecommunication system and so on, a connection between circuit boards, chips or systems is conducted through an electric metal cable. However, with the high-capacity and the increase of transfer rate of information such as in an advanced telecommunication system constituted with a high-capacity parallel computer or a 1 or more Tb/s class asynchronous transfer mode (ATM) switching system and so on, if used such metal cable, there is caused an electrical problem such as skewing or electromagnetic interference (EMI) and so on, thereby reducing operational efficiency of the system and making the integration of system difficult.
Recently, a technology of optical connection using an optical transceiving module has thus been developed wherein as a method for optical connection in the optical transceiving module, a direct coupling type of an optical receiving device to a ribbon optical fiber multi-channel optical connector with 45° tilt-angled reflector, a coupling type of a polymer optical waveguide having 45° tilt-angled reflector and to which an optical transceiving device is coupled, to a multi-channel optical connector, a coupling type of a polymer optical waveguide to which an optical transceiving device is vertically coupled, to a multi-channel optical connector, a vertical coupling type of an optical transceiving device fixed to a plastic package to a multi-channel optical connector and so on are used. Herein, as an optical transmission device, i.e., a light source, Vertical Cavity Surface Emitting Laser (VCSEL) Array is employed, and as an optical receiving device, i.e., a photodetector, a Photo Diode (PD) Array is employed.
Korean Patent Application No. 2000-7003642 (filing date: 2000 Apr. 4) entitled "Optical Module" is constructed such that light oscillated through a light exit is reflected at a 90° angle by an optical waveguide and is then transmitted to an optical fiber connected with an optical connector along a core formed to a substrate.
"ParaBIT-1: 60-Gb/s-Throughput Parallel Optical Interconnect Module" announced at ECTC 2000 on May, 2000 by N. Usui is constructed such that a 24-channel polymer waveguide film with a planar reflector tilted at a 45 degrees angle and a 24-optical fiber BF connector are connected with each other wherein the optical waveguide film and the connector are manually assembled.
Among the technologies introduced above, it is evaluated that the coupling type of the polymer optical waveguide having 45° tilt-angled reflector and to which the optical transceiving device is coupled, to the multi-channel optical connector is a most effective method in that the reflector being relatively easily formed, and an optical coupler, an optical switch, Wavelength Division Multiflexing (WDM) device, and so on are built in the polymer optical waveguide to achieve functional extension of the whole module.
However, when used such technology for optical coupling in order to manufacture an optical transceiving module for parallel optical interconnect having a subsequent extended function, although a misalignment is generated a little bit upon coupling the optical transceiving device with the optical fiber, a large coupling loss is caused so that satisfactory efficiency cannot be achieved. It is thus true that a structural improvement of the optical transceiving module for parallel optical interconnect is required in order to minimize the coupling loss.

Connection apparatus for parallel optical interconnect module and parallel optical interconnect module using the same

Electronics and Telecommunications Research Institute


An arrangement for determining transmission delay in a subscriber network which has a plurality of subscriber sets, a plurality of subscriber terminals (to one subscriber terminals to one subscriber terminal being connected at least one subscriber set by a transmission connection implemented in an electrical form), and a central unit, which is common to the several subscriber terminals and connects the subscriber sets to a public switched telephone network. In the subscriber network, time-division data transmission between the several subscriber terminals and the central unit occurs along a common transmission path. A value representing the transmission delay between the central unit and an individual subscriber terminal is determined, whereby a transmission of a subscriber terminal towards the central unit is synchronized in he subscriber terminal with the frame structure of a signal to be transmitted from the central unit towards the subscriber terminal. To enable performing the determination quickly by using simple equipment and by utilizing the transmission capacity efficiently, there is a specific message transmission time slot in the transmission frame for a transmission from the subscriber terminals towards the central unit, whereby determination of the value representing the transmission delay is performed in the central unit from a message transmitted by the subscriber terminal in the message transmission time slot, by measuring the location of the received message in relation to the frame structure of the signal to be transmitted from the central unit towards the subscriber terminal.

The invention relates to an arrangement for determining a transmission delay in a subscriber network.
The solution according to the invention is especially suitable for a measurement of timings of uplink messages (from a subscriber towards a central unit) of a point-to-multipoint network implemented by time-division technique. Such networks can be, for instance, combined cable television and telephone networks, so-called Passive Optical Networks (PONs) and wireless local loops.
In known subscriber networks based on the time-division technique, no subscriber-terminal-specific measurement of transmission delay is needed, for the connections are point-to-point connections. When the time-division technique is used in combined cable television and telephone networks or PONs, it is necessary to have a transmission delay for each subscriber terminal under control, because of the multipoint character of the connections. This means that a procedure of some kind has to be arranged in such a network for measuring the subscriber-specific transmission delay so that the subscriber terminals are able to learn the correct moments of transmission.
One known method of measuring a transmission delay is based on the looping of the signal to be transmitted outside an actual transmission channel. In these arrangements, the delay is measured by monitoring an own message, which is looped back from the other end of the connection. The transmission takes place outside the actual transmission channel, on a channel especially allocated for delay measurement. The looping can be made at the midpoint of the point-to-multipoint network, in which case a subscriber terminal measures the delay, or the subscriber terminal can be connected to form a loop, in which case a device at the midpoint of the network measures the loop delay.
Another known method of measuring a loop delay is a measurement to be performed on the actual transmission channel. Then, to a payload signal is added a low-level slow-changing message of DS-spread-spectrumsignal type (DS, standing for direct sequence), which message can be detected on the reception side by means of a specific correlation receiver. A low-level signal does not interfere a data transmission on the same channel, but allows a determination of the loop delay anyway.
Drawbacks of the known measuring methods are, e.g., separate device arrangements required, which make the equipment more complicated than before, and also the transmission capacity needed, which makes the bandwidth left for actual utility purposes smaller. A further drawback of the measurements to be performed outside the actual transmission channel is that the delay may vary in different frequency ranges.

Arrangement for defining a transmission delay in a subscriber network


A method and apparatus for adaptive multiple line prefetching. In one embodiment, the method includes the identification of a prefetch depth. As described herein, a prefetch depth may refer to a number of memory lines to be prefetched to temporary (cache) memory. Once the prefetch depth is identified, prefetching is performed according to the identified prefetch depth. During the prefetching, the prefetching is adjusted as changes in the prefetch depth are detected. Accordingly, the dynamic adaptive multi-line prefetching mechanism described herein promotes higher system performance by the use of a more efficient prefetching mechanism.

Modern computer systems exhibit a significant bottleneck between processors and system memory. As a result, a substantial amount of latency is incurred for completion of memory requests issued by a processor. One technique for reducing or avoiding latency between the processor and system memory is the use of data caches. As a result, computer systems may store requested data within volatile memory devices, such as cache memory devices. Accordingly, when a processor requires memory, the processor checks the data cache to determine whether the data is readily available and gather the data from such temporary memory devices to avoid the bottleneck that exists between processors and system memory.
Unfortunately, current computer systems consume an inordinate percentage of execution cycles solely on data cache. As a result, the program is halted until the data can be gathered from main memory. Unfortunately, substantial cache misses have a significant detrimental effect on the execution time and efficiency of user programs. One technique for reducing the amount of time required to process memory references is data prefetching. Data prefetching refers to a technique which attempts to predict or anticipate data loads. Once the data loads are anticipated, the data is preloaded or prefetched within a temporary memory in order to avoid data cache misses.
Accordingly, traditional instruction on data prefetching mechanisms focus on requested address patterns. These prefetch mechanisms aim to accurately predict which memory lines will be requested in the future based on what has been recently requested. However, prefetching can rapidly increase memory subsystem usage. The relationship between system memory, access latency and high memory subsystem usage negatively impacts the prefetching mechanism's effectiveness. In some symmetric multiprocessor (SMP) systems as well as chip multiprocessor (CMP) systems, aggressive prefetching drives up the memory subsystem usage, thereby increasing latency to the point that system performance is below non-prefetching levels. Therefore, there remains a need to overcome one or more of the limitations in the above-described existing art.

Apparatus and method for an adaptive multiple line prefetcher


To prevent piracy or leakage of data content, a cryptography technique and electronic watermark technique are combined together and used. In a data content supplied to a user, a user data is entered as electronic watermark by a data management center, and the data content with an electronic watermark entered in it is encrypted using a crypt key and is supplied. The encrypted data content is decrypted using a crypt key distributed from the data management center and is used. In case it is to be stored, it is encrypted using another crypt key. In case the data content is copied and transferred to other user, a user data of the other user is entered as electronic watermark, and a scenario to enter the user data of the other user as electronic watermark is registered at the data management center, and the data content with electronic watermark entered in it is encrypted using another crypt key and is supplied. When the validity of the other user is confirmed by the scenario, another crypt key is distributed to the other user. The encrypted data content is decrypted using another crypt key and is used. When it is to be stored, it is encrypted using still another key. In case the data content has been copied and transferred illegitimately, it is possible by verifying the electronic watermark to identify the user who has copied and transferred the data content illegitimately.

1. Field of the Invention
The present invention relates to a system for managing data for using, i.e., storing, copying, editing, or transferring digital data content.
2. Background Art
Because analog data content is deteriorated in quality whenever storing, copying, editing, or transferring it, controlling copyrights associated with these operations has not been a serious problem. However, because digital data content is not deteriorated in quality after repeatedly storing, copying, editing, or transferring it, controlling copyrights associated with these operations for digital data content is a serious problem.
Because there has been hitherto no adequate method for controlling a copyright for digital data content, the copyright is handled by the copyright law or contracts. Even in the copyright law, compensation money for a digital-type sound- or picture-recorder is only systematized.
Use of a data content includes not only referring to its contents but also normally effectively using by storing, copying, or editing obtained data content. Moreover, it is possible to transmit edited data content to another person via on-line basis by a communication line or via off-line basis using a proper recording medium. Furthermore, it is possible to transmit the edited data content to the database to be registered as new data content.
In a conventional database system, only character data content is handled. In a multimedia system, however, audio data content and picture data content which are originally analog data contents are digitalized and formed into a database in addition to the data content such as characters which have been formed into a database so far.
Under these circumstances, how to deal with a copyright of data content in a database is a large problem. However, there has not been adequate copyright management means for solving the problem so far, particularly copyright management means completed for secondary utilization such as copying, editing, or transferring of the data content.
The inventor of the present invention proposed a system for managing a copyright by obtaining a permit key from a key control center via a public telephone line in Japanese Patent Laid-Open No. 46419/1994 (GB 2269302A) and Japanese Patent Laid-Open No. 141004/1994 (U.S. Pat. No. 5,504,933) and moreover, proposed an apparatus for managing the copyright in Japanese Patent Laid-Open No. 132916/1994 (GB 2272822A).
Moreover, a copyright management method for primary utilization of digital data content such as display (including process to sound) or storage including real-time transmission of the digital data content in a database system and secondary utilization of the digital data content such as copying, editing, or transferring of the digital data content by further developing the above invention is proposed in Japanese Patent Application No. 64889/1994 (U.S. patent application Ser. No. 08/416,037).
The database copyright management system of the above application in order to manage the copyright, either one or more of a program for managing the copyright, copyright information, and a copyright control message are used in addition to a use permit key corresponding to a requested use, and data content which has been transferred with encryption is decrypted to be used for viewing and editing, and the data content is encrypted again when used for storing, copying and transferring.
The copyright control message is displayed when utilization beyond the range of the user's request or authorized operation is found to give caution or warning to a user and the copyright management program performs monitoring and managing so that utilization beyond the range of the user's request or authorized operation is not performed.
On the other hand, it is widely practiced to establish LAN (Local Area Network) by connecting computers with each other in offices, organizations, companies, etc. Also, a plurality of networks are connected with each other, and Internet is now organized in a global scale, by which a plurality of networks are utilized as if they are a single network.
In LAN used in an organization such as firms, secret information is often stored, which must not be disclosed to outsiders. For this reason, it is necessary to arrange the secret information in such a manner that only a specific group of users can gain access and use such information, and such access is generally placed under control to prevent leakage of secret information to outsiders.
There are roughly two methods to control the access: a method to control access with access permission, and a method to do it by encryption.
The method of access control by access permission is described in U.S. Pat. Nos. 5,173,939, 5,220,604, 5,224,163, 5,315,657, 5,414,772 and 5,438,508, in EP 506435, and in JP Laid-Open 169540/1987.
The access control method based on encryption is disclosed in U.S. Pat. Nos. 4,736,422, 5,224,163, 5,400,403, 5,457,746, and 5,584,023, in EP 438154 and EP 506435, and in JP Laid-Open 145923/1993. The access control method based on encryption and digital signature is described in U.S. Pat. Nos. 4,919,545 and 5,465,299.
Intranet is now being propagated, in which a plurality of LANs are connected with each other via Internet and these LANs are utilized as if they are a single LAN. In the intranet, information exchange is performed via Internet, which basically provides no guarantee for prevention of piracy, and information is encrypted to prevent the piracy when secret information is exchanged.
The prevention of information piracy during transmission by means of encryption is disclosed in U.S. Pat. Nos. 5,504,818 and 5,515,441, and the use of a plurality of crypt keys is described in U.S. Pat. Nos. 5,504,816, 5,353,351, 5,475,757, and 5,381,480. Also, performing re-encryption is described in U.S. Pat. No. 5,479,514.
When encrypting, management of crypt key including transfer and receipt of crypt key becomes an important issue. Generation of keys by IC card is disclosed in U.S. Pat. No. 5,577,121, and encryption/decryption by IC card is disclosed in U.S. Pat. Nos. 5,347,581 and 5,504,817. Also, electronic watermark technique is described in EP 649074.
In the video conference system, a television picture has been added to the conventional voice telephone set. Recently, the video conference system is advanced in which a computer system is incorporated in the video conference system so that the quality of the voice and the picture are improved, and data content can be handled at the same time as well as the voice and the picture.
Under these circumstances, security against the violation of the user's privacy and the data content leakage due to eavesdropping by persons other than the participants of the conference are protected by the cryptosystem using a secret-key.
However, since the conference content obtained by the participants themselves are decrypted, in the case where participants themselves store the content of the conference and sometimes edit the content, and further, use for secondary usage such as distribution to the persons other than the participants of the conference, the privacy of other participants of the video conference and data content security remains unprotected.
In particular, the compression technology of the transfer of data content is advanced while the volume of the data content storage medium is advanced with the result that the possibility is getting more and more realistic that all the content of the video conference may be copied to the data content storage medium or transmitted via a network.
Also, electronic commerce system with digital data content for commercial dealing is now being used for practical applications. Above all, various types of experiments are now under way for digital cash system to exchange electronic data content instead of cash so that the system can be used by general public.
The digital cash system which has been proposed so far is based on a secret-key cryptosystem. The encrypted digital cash data content is transferred from a bank account or a cash service of a credit company, and is stored in an IC card so that a terminal device for input/output is used to make a payment. The digital cash system which uses this IC card as a cash-box can be used at any place such as shops or the like as long as the input/output terminal is installed. However, the system cannot be used at places such as homes or the like where no input/output terminal is installed.
Since the digital cash is an encrypted data content, any device can be used as the cash-box which stores digital cash data content, in addition to the IC card, as long as the device can store encrypted data content and transmit the data content to the party to which the payment is made. As a terminal which can be specifically used as the cash-box, there are personal computers, intelligent television sets, portable telephone sets such as personal digital assistant (PDA), personal handyphone system (PHS), intelligent telephone sets, and PC cards or the like which has an input/output function.
It is desirable that the digital cash is processed as an object associated with data content and functions instead of being as a simple data content. In handling a digital cash, there are a common digital cash form, an unentered digital cash form private for an owner, an entry column in the digital cash form private for the owner, a digital cash data content showing an amount of money, an instruction of handling digital cash, and a digital cash form private for the owner in which an amount of money is entered. In an object-oriented programming, concepts such as an object, a class, a slot, a message and an instance are used.
In these correspondence relations, the common digital cash form is the object; the unentered digital cash form private for an owner: the class; the entry column of a digital cash form private for the owner: the slot; the instruction of handling digital cash: the message; and the digital cash form private for the owner in which an amount of money is entered: the instance.
A digital cash data content comprising the amount of money and the like is used as an argument, then, is transferred and stored in the slot which is referred to as an instance variable by the message so that a new instance is made which is a digital cash in which the amount of money is renewed.
The encryption technique used in the data management system is utilized not only in the distribution of copyrighted data content but also in the distribution of digital cash.
Then, basic encryption-related technique used in the present invention is described below.


A scheduling method and apparatus for use by a processor that controls storage devices of a data storage system is presented. The method allocates processing time between I/O operations and background operations for predetermined time slots based on an indicator of processor workload.

The invention relates generally to data storage systems, and in particular, to job scheduling.
In typical data storage systems, a storage controller serves as an interface between external host computers and the physical storage devices of the data storage system, and thus controls all back-end (or device-side) operations. The back-end operations can include services for I/O, such as read misses, write destaging and read prefetching. The back-end operations can also include non-I/O background operations, e.g., activities related to data copy, and other activities. The scheduling of these two classes of back-end operations, that is, I/O operations and background operations, which compete with each other for storage controller resources, has a major effect on the performance of the data storage system as a whole.

This patent is subject to a terminal disclaimer.

Management of background copy task for point-in-time copies


A brazing method for brazing a material without using a flux includes performing brazing in an inert gas atmosphere, in a state in which the material to be brazed is covered with a cover member formed of an upper cover portion covering the whole upper portion of the material to be brazed and side cover portions covering at least some of the side portions of the material to be brazed, with the upper cover portion contacting the upper portion of the material to be brazed, and the material to be brazed and the cover member are held with a heat transmission promoting member formed of an upper heat transmission promoting portion and a lower heat transmission promoting portion, with the upper heat transmission promoting portion contacting the upper cover portion, and with the lower heat transmission promoting portion contacting the lower portion of the material to be brazed.

Aluminum materials have high thermal conductivity and light weight, and frequently used for coolers, such as the coolers mounted on automobiles.
These coolers have a structure in which coolant, such as water, is circulated through a channel formed of a combination of members to move and radiate heat. The members forming the cooler is metallically bonded by brazing.
As an aluminum material subjected to brazing, a brazing sheet is used in which an aluminum alloy sheet serving as a core material is cladded with a brazing material on its one side surface or both side surfaces. An aluminum alloy having a melting temperature of exceeding 620° C. is used as a core material alloy of typical brazing sheets, and an Al—Si alloy having a melting start temperature of 577° C. is used as a brazing material to be cladded.
To produce a heat exchanger by brazing, the brazing sheets are formed into shapes of heat exchanger members and then combined, and heated to a temperature of around 600° C. In this manner, only the brazing material portion of the brazing sheet is molten to be brazed with other members.
To enable brazing, an oxide film on the surface of the material needs to be broken. In brazing of aluminum, a flux is supplied to the brazing portion to break the oxide film. For example, generally, K—Al—F-based compound powder serving as a flux is suspended in water and/or a solvent, and applied to the brazing portion of the aluminum material. During increase in temperature of brazing, the flux is molten onto the brazing portion, covers the surface of the aluminum material, and breaks the oxide film existing on the surface. In addition, when the temperature is further increased, the Al—Si-based brazing material of the brazing sheet is molten and metallically bonds with the surface of the bonding target member, because the oxide films on the surface of the brazing material and the surface of the bonding target material are broken by the effect of the flux, and the brazing is completed.
In recent years, reduction in size and weight is required for heat exchangers for automobiles. To meet the requirements, materials having high strength and small thickness tend to be used as aluminum materials forming heat exchangers. Having Mg in the materials is effective to increase the strength of the aluminum materials, and use of aluminum materials containing Mg is desired also in heat exchangers.
However, when an aluminum material containing Mg is brazed under existence of a K—Al—F-based compound flux, the flux reacts with Mg on the surface of the material and generates a compound during heating for brazing. For this reason, the effect of the flux of removing the oxide film is lost, and brazing becomes impossible. For this reason, it is required to limit the Mg content in the aluminum material used for the brazing using a flux.
Methods accordingly having been proposed are the methods of performing brazing by heating an aluminum material containing Mg in an inert gas without using a flux. For example, Patent Literature 1 discloses a method for performing brazing without using a flux by covering the material to be brazed to suppress a flow of the atmosphere gas inside the cover and disposing an Mg supply source inside the cover. Patent Literature 2 discloses a method for performing brazing by using a brazing sheet formed of an aluminum alloy containing Mg in a constituent member to form a hollow structure. In this method, brazing is performed without applying a flux inside the hollow structure, and by applying a flux outside the hollow structure. Patent Literature 3 discloses a method for performing brazing without using a flux by heating the material to be brazed disposed in a furnace and covering the material to be brazed with a wind-shield jig heated in advance.

Brazing method for brazing material formed of aluminum alloy in inert gas atmosphere without using flux


An electrical connector comprises an insulative housing, a plurality of conductive terminals secured in the insulative housing, a metal shell shielding around the insulative housing and a magnetic element retained in the metal shell. The metal shell forms an accommodating room for receiving the magnetic element. The magnetic element has an outer surface and a recess defined on the outer surface. The metal shell has a retaining arm corresponding to the recess. The design of the recess and the retaining arm make a better retaining effectivity for the electrical connector.

1. Field of the Invention
The present invention generally relates to an electrical connector, and more particularly to an electrical connector with magnetic element retained therein.
2. Description of Related Art
U.S. Pat. No. 7,517,222 discloses an electrical connector comprising an insulator, a plurality of conductive terminals accommodated in the insulator, a metal shell shielding around the insulator and a magnetic element retained in the insulator. The metal shell includes side walls and a rear end wall shielding around the insulator. The magnetic element with smooth surface is accommodated in the metal shell. The front face of the magnetic element is exposed from the shell so as to mate with a corresponding magnetic element of the complementary connector. Normally, the manner of securing the magnetic element of the electrical connector is using glue or adding additional retaining component. However, some of the manners have a poor assembly efficiency, and some of the manners have a poor retaining force.
In view of the foregoing, an electrical connector with at least a magnetic element firmly secured therein would be desirable.

Electrical connector with magnetic element


A dummy SRAM cell for use in a dummy bit line circuit uses the same transistors as used in a standard SRAM cell, which includes first and second subsets of transistors configured as first and second bit line output circuits. The dummy SRAM cell includes the same first and second subsets of transistors, with the first transistors configured as a dummy bit line output circuit having substantially the same electrical characteristics as the first bit line output circuit of the standard SRAM cell. Further, the second transistors, which are not otherwise needed for the dummy SRAM cell function, are reconfigured as a voltage tie circuit for the dummy bit line output. Using the second transistors for this purpose obviates the need to add additional transistors to form a voltage tie circuit for configuring the dummy bit line output circuit as a load or driver for the dummy bit line.

SRAMS, especially high-density SRAMs utilizing small device geometries, generally incorporate sense amplifiers to provide the output drive capability for memory reads. Each sense amplifier detects the differential voltage across a corresponding pair of complementary bit lines (BL and BL′) in an SRAM array. Outputting correctly sensed bit data from the memory array depends on sense amplifier settling times, which in turn depend on a number of process-related and environmental variables.
For example, the effective capacitance of each SRAM cell, and the number of SRAM cells (rows) connected to the bit lines, influences the charge and discharge times of the bit lines and therefore influences the settling time for reliably sensing differential bit line voltages via the sense amplifiers. Cell capacitance varies with variations in the process—e.g., variations in metallization layer widths—and, more generally, the overall circuit timing changes with process, temperature, and voltage variations.
Designers address read timing variations in a number of ways. One conventional approach generates read clock timing via circuitry that tracks changes in the actual SRAM array. For example, a designer may implement a "dummy" bit line that is loaded with additional SRAM cells that are not part of the actual memory array. By using the same SRAM cells and design rules as the actual bit lines, the charge/discharge times of the dummy bit line proportionally track those of the real bit lines. As such, using the dummy bit line in read clock generation automatically compensates for timing changes in the SRAM array.
However, the use of dummy bit lines is not without certain disadvantages. For example, common existing and developing process technologies do not permit the direct connection of system voltages to transistor gate inputs. Several considerations factor into this design constraint, including electrostatic damage (ESD) concerns.
The constraint is problematic because configuring a dummy bit line requires tying a certain number of the SRAM cells high and the remaining ones low. With direct connections to VDD (power) and VSS (ground or reference) disallowed by the design rules, an additional "tie" structure must be used for each of the standard SRAM cells on the dummy bit line. Each tie structure generally includes two transistors to make the VSS or VDD connection via drain/source paths and the corresponding consumption of real estate by the tie structures can be significant.

Method and apparatus for a dummy SRAM cell


A mobile physical training system and method, wherein a wheeled platform is secured to a user via a bodyworn harness and/or belt, wherein the user can easily and selectively manipulate the amount of resistant weight carried by the platform, and wherein consistent, hands-free delivery the resistant weight force is realized for both pushing and pulling actions, thereby enabling the physical training system of the present invention to target speed, strength, and endurance training for individuals of virtually any skill level during a variety of training activities, such as walking, jogging, forward, backward and lateral running, push training, mobility training, and wheelchair training.

It is well accepted that physical training can be beneficially enhanced through the use of resistance training devices. For example, some individuals have utilized weight vests to focus on speed, power and endurance training while walking or jogging. However, such vests can disadvantageously exert pressure on the wearer's lower back, knees and ankles and are frequently too heavy for the average person to utilize.
Running chutes are also used by some athletes, wherein the chute dimensions determine the resistant pulling forces exerted on the runner. Unfortunately, although running chutes can be good for speed and strength training, a user must be able to run at a certain speed in order to make use thereof. Thus, such devices are not helpful for many runners, walkers or joggers.
Unlike running chutes, harness worn sleds offer variable weight resistance, enabling use for speed, power and some endurance training. These sleds are designed to slide across flat grassy surfaces, but are not suitable for use on most pathways commonly utilized by walkers and joggers. Moreover, the use of a nylon cord for pulling such a sled introduces inconsistent force delivery and can be disadvantageously dangerous to the pulling individual on a downhill run.
Another type of resistant device offers a two-wheeled design for use on a larger variety of surfaces. However, known devices of this type that are adapted for cardiovascular workouts unfortunately rely upon complicated resistance mechanisms. Further, although some such devices include rods to enable pulling and pushing, the rods must be disadvantageously held within a user's hands, thereby limiting the natural range of movement and, by design, imparting a disadvantageous change in traction between the wheels and the ground when movement is initiated.
Therefore, it is readily apparent that there is a need for a mobile physical training system and method, wherein a wheeled platform is secured to a user via a bodyworn harness and/or belt, wherein the user can easily and selectively manipulate the amount of resistant weight carried by the platform, and wherein consistent delivery the resistant weight force is realized for both pushing and pulling actions, thereby enabling the physical training system of the present invention to target speed, strength, and endurance training for individuals of virtually any skill level during a variety of training activities, such as walking, jogging, forward, backward and lateral running, push training, mobility training, and wheelchair training, and thus avoiding the above-discussed disadvantages.

Mobile physical training system and method thereof


Systems, methods, and computer-readable media are provided for signaling the presence of a fault in a multi-band optical network or other communication system. In response to a detected fault in a multi-band communication system impacting a specific band of the multi-band communication system, a method, according to one implementation, may include a step of creating a fault signal corresponding to the detected fault. The method may also include the step of conveying the fault signal to at least one of an upstream controller and a downstream controller of the multi-band communication system to trigger an action for handling the fault on the specific band. The action may be handled independently of other actions associated with one or more other bands of the multi-band communication system.

In a communications system, such as an optical transmission network, it is generally necessary to detect when a fault occurs such that certain actions can be taken to recover the system to a normal operating condition. In a conventional optical transmission system, detected faults are usually viewed as problematic for an entire section or line of the network. Thus, when a fault is detected, actions are taken to avoid or correct the problematic section or line altogether.
Conventional systems can handle these line-faults, which may include a) line fiber cuts that impact all spectrum bands, b) any amplifier or line-facing optical component failure or circuit pack removal, or others. For either of these types of faults, conventional systems normally treat them as an Optical Multiplex Section (OMS) level fault. The node detecting the fault may generate an OMS Forward Defect Indication (OMS-FDI) or may generate an OMS Reverse Defect Indication (OMS-RDI) for the entire OMS. The OMS-FDI may be used to notify a downstream OMS of this upstream section fault so that a downstream multiplexer can take necessary actions. The OMS-FDI can work as a digital notification so that the downstream multiplexer can trigger an Amplified Spontaneous Emission (ASE) replacement in an ASE loaded system. The OMS-RDI can be used to notify a local section head about the section fault condition so that local section head can freeze all of its control actions until the faulted line system is recovered.
In a Layer 0 Control Plane (L0CP) (e.g., optical line), if a line fault is detected and either an OMS-FDI or OMS-RDI is raised, a controller in the control plane may be configured to restore all channels of the line system on another path. In some cases, the controller in the control plane may be configured to avoid the link for further restoration.
Although these techniques may be helpful in many situations, the conventional systems may not be optimized to perform restoration and/or link avoidance on a finer scale to only conduct actions where they are needed. For instance, in a multi-band optical system (e.g., C-band plus L-band), the conventional systems may have certain shortcomings. Since conventional systems do not handle band-specific failure conditions (i.e., a fault that is specific to one band), there is a need in the field of multi-band optical networking systems to handle faults per band. Instead of this, conventional systems might trigger a Layer 0 (L0) restoration on all transmission bands and/or may trigger an ASE replacement for all transmission bands in a downstream section multiplexer.
In addition, for a Raman amplified ASE loaded system, the ASE replacement mechanism may be considered as the core feature and may rely on a Loss of Signal (LOS) detection on a channel. However, the ASE replacement mechanism may fail in a multi-band transmission system due to additional Stimulated Raman Scattering (SRS) and tilt generated in the system on a band-specific or common-line failure. In either case, the existing methods fail to resolve the condition. Again, there is therefore a need for systems capable of handling faults on a per band basis.

Per-band fault signaling in a multi-band optical transmission system


A fishing rod foundation and methods for constructing and adjusting a fishing rig. The fishing rod foundation may include a cylindrical element inserted in a tubular, the tubular having at least three portions. The first portion and second portions may be configured to receive a rod blank. The third portion may be configured to provide a stop for fishing rod parts to be added to the fishing rod foundation exterior. The third portion may include a threaded section that engages a locking nut for locking and unlocking the position of the cylindrical element relative to the tubular. The method may include construction of a fishing rod by adding a rod blank and other parts to the fishing rod foundation. Another method may include adjusting the fishing rig using the locking/unlocking feature of the fishing rod foundation.

1. Field of the Disclosure
This disclosure generally relates to the field of fishing, and, in particular, formation and assembly of fishing rods and rigs.
2. Description of the Art
Generally, fishing rigs are used for catching fish from an aquatic environment. Fishing rigs come in a wide variety and are often specialized for specific uses. Fishing rigs may be designed around optimizing characteristics such as ease of use, durability, reduced maintenance, effectiveness in competition, etc. While fishing, a user may require multiple fishing rigs, each optimized for different purposes (weight of lure, expected catch size, type of competition, etc.). Fishing rig dimensions may also vary based on user characteristics, including size of the user and arm length. Fishing rigs may include numerous elements, such as rod blanks, fishing line, fishing line guides, reel seats, butts, counterweights, etc. Fishing rigs are built around a rod blank that serves as an attachment point for other elements. However, rod blanks are typically made of flexible materials, such as fiber glass, which is subject to damage during handling and use and deterioration due to exposure to the environment. Since a rod blank has a fixed length, a fishing rig built around a rod blank will have a limited range of users (based on user size and arm length) and a fixed set of uses unless modified. Modification options for a fishing rig built around a rod blank are often limited based on properties of the rod blank and the need for complex equipment (manufacturing environment) to perform the modification. A broken rod blank may require factory equipment unavailable to the user. If a rod blank is damaged, the entire fishing rig must be rebuilt around a new rod blank. What is needed is a fishing rig foundation that is more robust than a rod blank to serve as the attachment point for the fishing rig elements, and may be assembled/modified by the user in the field.

Multi-functional rod foundation system and method


A lens structure is provided. The lens structure comprises a first barrel, a second barrel and a third barrel. The first barrel has a first groove and comprises a first pin. The second barrel has a second groove and comprises a second pin. The third barrel has a third groove. The first barrel is rotatably disposed outside of the third barrel. The second barrel is disposed in the inside of the third barrel. The second pin of the second barrel slides along the third groove of the third barrel and the first groove of the first barrel. The first pin of the first barrel slides along the second groove of the second barrel.

1. Field of the Invention
The invention relates in general to a lens structure, and more particularly to a lens structure with multiple barrels.
2. Description of the Related Art
Along with the advance in technology, digital camera mechanism has been widely used in various digital products such as digital camera, digital video recorder, mobile phone, personal digital assistant (PDA). The digital camera mechanism comprises a lens structure and an image sensor. The lens structure focuses an image on the image sensor, which then converts an optical image signal into an electrical signal.
Conventional lens structure comprises a number of barrels which move relatively to each other. A straight forward barrel of the barrels has a groove, which defines an optical zooming path. Through the groove, the straight forward barrel may move in a straight line to zoom in and/or zoom out.
Since the optical zooming path is defined by the groove of only one straight forward barrel, the length of the optical zooming path is limited. However, to increase the length of the optical zooming path, the thickness of the straight forward barrel needs to be increased, and the increase in thickness will increase the volume of the digital camera mechanism and reduce product competitiveness.


The process of the present invention can easily produce a solid polymer electrolyte having a high ion conductivity, by reacting an acrylic copolymer comprising structural units represented by the following formulas (I) and (II) with a compound represented by formula (III) Y—R—Y, provided that in formulas (II) and (III), X and Y are a combination of an isocyanate group and a hydroxyl group, thereby being solidified

In recent years, organic solid polymer electrolytes have been extensively developed, which electrolytes have properties such as formability, a capability of being easily formed into a large area film, flexibility, and excellent adhesivity to electrodes, comparing with inorganic solid electrolytes.
Some polymers have been proposed in the form of organic solid polymer electrolytes. However, since for example, such polymers have been produced by electrolytic polymerization or a process requiring a long reaction time as disclosed in Japanese Patent Laid-Open Publication Nos. 4-171603 and 60-31555, the processes disclosed therein had a problem in productivity. The process disclosed in Japanese Patent Laid-Open Publication No. 2-298504 involves copolymerization of a precursor monomer and thus may encounter the shrinkage of the product caused by the polymerization, leading to a problem that it is difficult to produce such polymers easily from the industrial point of view.

Process for producing solid polymer electrolyte