In a storage apparatus for a vehicle including a lid which can rotate about a pivot, and a damper device having a cord-like connecting member and adapted to generate damping force against pulling force from the connecting member, wherein a connecting wire (the connecting member) is pulled, when the lid rotates in one direction, thereby to generate the damping force in the damper device, it is so constructed that a damping force control member having a guide face for the connecting wire is fixed to the lid, and when the lid has rotated in a direction of receiving the damping force, the connecting wire is wound around the guide face and pulled.

1. Field of the Invention
The present invention relates to a storage apparatus for a vehicle, which has a lid rotatable about a pivot, such as a glove box provided on an instrument panel of the vehicle.
2. Description of the Related Art
In many storage apparatuses for vehicles, such as glove boxes, there are provided damper devices in order to restrain sudden rotation of a lid by its own weight. As the damper device of this type, a damper of air system as shown in JP-UM-A-5-76894, for example, has been proposed.
The conventional damper device of this type, though not specifically illustrated herein, mainly includes three components, namely, a cylinder, a piston, and a pulling wire. The piston provided with a seal ring on its periphery is slidably contained in a cylinder and urged by a compressive coil spring in one direction. Meanwhile, a guide cap is fitted to an opening of the cylinder at its front side, and one end of the pulling wire which is arranged in a desired direction is connected to the piston, by way of the guide cap, inside the cylinder.
Moreover, a back wall having a cylindrical part and an air port is integrally formed with a backward end part of the cylinder. In the cylindrical part of the back wall, a seat valve formed with an orifice, a backup spring, and an air filter are arranged in this order, and a side of the air filter is retained by a retainer having an opening.
The damper device having the above described structure is mounted on the vehicle in such a manner that the cylinder is fixed to either one of the glove box side and the instrument panel side, and the other end of the pulling wire which has been arranged by way of the aforesaid guide cap is fixed to the other side. Then, on occasion of actual operation, by rotating the glove box in an opening direction utilizing its own weight, the pulling wire is pulled outwardly from the cylinder, and accordingly, the piston will be slid toward the guide cap against an urging pressure of the compressive coil spring, thereby to permit the glove box to rotate.
However, while the glove box rotates, air will be sucked in from minute holes of the air filter, according to the sliding motion of the piston, through the orifice of the seat valve into the cylinder. Because negative pressure will be formed inside the cylinder and damping force will be exerted on the sliding motion of the piston, an opening motion of the glove box will be controlled, ensuring that the glove box will be slowly rotated in the opening direction.
However, the lid of the glove box is generally kept in almost upright position in a completely closed state, and has its center of gravity positioned above a rotation pivot. The center of gravity will move, along with the opening motion, in a direction away from a vertical line passing the rotation pivot. Accordingly, when the lid conducts the opening motion from the completely closed state to a fully opened state, the rotation moment of the lid by its own weight has been small at the beginning of the opening motion, and thereafter, becomes gradually larger.
Therefore, in order to open the lid at a fixed speed, it is necessary to control the damping force by the damping device so that the damping force may become gradually larger according to the opening motion of the lid.
In JP-UM-A-62-43847, in order to control the damping force of the damper device, attention has been paid to an orbit of a pivotal point (a connecting point) of a rod transmitting the damping force of the damper device, with respect to the lied, and there is disclosed such a structure that a tangent line is drawn at an intermediate position of an arc-shaped orbit of the rod from the completely closed state to the fully opened state of the lid, and a pivotal point (a mounting point) of the damper device with respect to the glove box is positioned on the tangent line.
However, as the structure described in JP-UM-A-62-43847, the mounting position of the damper device has been determined, only from a viewpoint of controlling the damping force, and freeness of designing the glove box has been restricted. Specifically, a size, a shape, and assembling position of the glove box have been severely designed in adjustment relative to various other components to be incorporated into the instrument panel of the vehicle. Under the circumstances, it is desirable that the mounting position of the damper device too can be flexibly subjected to change of design, while adjustment is made with respect to these components in the surroundings.


A density/solute monitor having at least one ultrasound probe, a signal processing unit, and a computing mechanism, and process for using the same, to measure phase shift between emitting and receiving ultrasound, sound velocity, compressibility, density, and solute concentration of fluid flowing through a fluid processing system. The ultrasound probe emits and receives ultrasound waves through the fluid and the signal-processing unit and computing mechanism process the ultrasound waves to determine phase and time shift. The computing mechanism converts phase shift to density, compressibility, and solute concentration measurements of the fluid. Calibrating fluids calibrate the detected phase shift in terms of sound velocity in the factory. Measurements provide information about passage of solutes and flow to achieve better solute collection efficiency, solution purity, and control of fluid processing systems. The density/solute monitor can include other detection modalities such as an optical probe, making concentration measurements of the density/solute monitor more specific to selected solutes.

Two classical methods of measuring density of a fluid include: 1) measuring the weight of fluid in a flask of fixed volume; and 2) employing the buoyancy of a density float for the assessment of fluid density. Both of these methods require collection of large samples from a fluid-processing device such as a pipeline or reactor for off-line measurements. For a given solution, density relates to the solute concentration of the solution. Although the density measurement is not specific to what solute is in the solution, these two density measurement methodologies and others to be described later have been used as a means to assess solute concentration.
A mechanical device based on resonance has been available to measure density of a fluid sample or that of a flowing fluid on-line. The device has a hollow U-tube with its two ends fixed on a heavy base. The fluid can be infused to fill the U-tube or made to flow along the tube. By measuring the frequency that the U-tube resonates, one then determines the mass of fluid in the U-tube. Since its volume is fixed, the mass is converted to the fluid density. This mechanical density measuring system (MDMS) has high sensitivity and reproducibility in the dynamic measurement of fluid density.
As a fourth density measurement method, one measures the sound velocity of fluid for the determination of the compressibility and density of fluid. Krivitski, in U.S. Pat. Nos. 5,453,576 and 5,685,989 describes an apparatus and method for measuring several hemodynamic parameters by using a sound velocity sensor. The ultrasound transducer is excited to emit a pulse of ultrasound. After its passage through a fluid medium such as the blood, a receiving transducer senses the ultrasound pulse. A protocol to compare the excitation and receiving ultrasound signals determines the transmission time through the blood and subsequently its sound velocity. The information contained in the '576 and the '989 patent is incorporated by reference as though cited in its entirety. When their device is used to measure blood density change for the computation of blood volume, a linear approximation of a non-linear relationship is employed to convert the sound velocity to the density of the blood. Furthermore, the device of the '576 patent has limited sensitivity so as to require the imposition of a large change in blood density for accurate assessment of blood volume.
The system patented by Schneditz in U.S. Pat. No. 5,830,365 also utilizes sound velocity for the measurement of transmission time delay through the blood and then its total protein concentration. A clinical protocol to change the ultrafiltration rate as a patient undergoing hemodialysis treatment is described to produce the change in density, which is assessed through a sound velocity monitor. An equation is deduced to compute from the change measurement the blood volume circulating in the patient. The monitor to measure density is about one order of magnitude less sensitive than that provided by the MDMS or our density/solute monitor. As a result, the application of Schneditz's method to measure blood volume is limited to cases that the change in sound velocity being imposed through the clinical protocol is large.
The fifth density measurement method employs the attenuation due to the absorption of radioactivity by the fluid as a means to assess its density. Approval by regulatory agency is required for this method.

Density/solute monitor of multi-modalities and signal processing scheme


The body movement of a person in a bed or a seat is detected by a piezo-electric element without contacting to the body, and absence or presence in the bed or the seat and rough body movement are judged by detecting the fine body movement propagated by the functioning of heart and breathing of the body, and in case the presence in bed is judged the time measurement operation is started by the timer, and by judging the absence and rough body movement the time measurement is reset. It is judged that the body on the bed or the seat has fallen asleep when the measurement time of the timer exceeds a predetermined set time.

1. Technical Field
The present invention relates to a human monitoring apparatus for detecting the presence of a human body and for detecting sleep of the body on a bed or a seat.
Conventionally, this type of human monitoring apparatus is what detects, for example, a brain wave and movement of eyeballs of the body and processes the signal waveform detected to judge falling asleep (Japanese unexamined published Patent Application No. 62-253034 (1987), or detects a pulse wave of the body and processes the signal waveform to judge falling asleep (Japanese unexamined published Patent Application No. Sho 63-150047 (1988)), which are both constituted of, as shown in FIG. 1, detecting means 1 for detecting physical signals such as the brain wave, movement of the eyeballs and pulse wave, signal processing means 2 for processing the signal from the detecting means 1 and judging means 3 for judging the falling asleep by outputs from signal processing means 2.
In the conventional configurations, however, since they are constructed such that the detecting means 1 for detecting the brain wave, movement of eyeballs and pulse wave is installed directly on the scalp or skin of the body, such a problem was encountered that an inharmonious feeling due to the installation may disturb the sleeping.
2. Disclosure of the Invention
The present invention is designed to solve the above-mentioned problems, and therefore, it is an object thereof to provide a human monitoring apparatus which judges, first, whether there is the body on a bed or a seat so as not to make an erroneous detection as the body movement when things are placed on the bed or the sear, and detects sleep easily without installing and contacting the detecting means to the human body. By viewing the fact that movement of the body (hereinafter referred to as body movement) comes to a standstill on sleep, the human monitoring apparatus detects the body movement without contacting the body and detects the sleep in response to the quiescent time of the body movement.
In order to achieve the above-mentioned object, the present invention includes body movement detecting means which in turn includes at least one piezo-electric element disposed on a bed or a seat and detects movement of a human body on the bed or the seat. The body movement detecting means producing a signal. Also includes are absence judging means for judging the presence of a body on the bed or seat when the signal level is above the first set value and below a second predetermined set value, and body movement judging means for judging that the body has produced a rough body movement such as turning over on the bed or the seat when the signal level is above the second set value.
The present invention further includes a timer for resetting a time measurement whenever the absence or rough body movement is judged and starting the time measurement when the presence is judged, and sleep judging means for judging that the body has fallen asleep when a measured time of the timer exceeds a predetermined set time.
In the present invention, the body movement detecting means is constituted by, at least one piezo-electric element disposed on bedding or a seat, a filter which filters a certain specific frequency component with respect to respective signals of the piezo-electric element, an amplifier which amplifies the filter signal, a rectifier which rectifies the amplifier signal and a smoothing device which smoothes the rectifier signal.
The present invention is constituted by a piezo-electric element including of a high-molecular piezo-electric material such as polyvinylidene fluoride, which is processed into a thin film and bonded with a flexible electrode film on both surfaces thereof to form a tape.
In the present invention, the piezo-electric element is contained in a sheet shaped bag, and a stretchingly-and-shrinkingly movable stretch-shrink parts are provided on the end parts of the bag, and in addition, engaging and disengaging parts, which enable engaging and disengaging of end tip parts of the stretch-shrink parts from each other, are provided on respective ones of the end parts.
The present invention provides display means for displaying the signal level of the body movement detecting means, and first setting means capable of manually changing over between the first set value and the second set value, based on the signal level displayed by the display means.
The present invention comprises first memory means which samples and stores the signal level of the body movement detecting means at a predetermined period when the presence in,the bed or the seat is judged by the presence judging means, first operating means which operates a minimum value and a maximum value of the content stored in the first memory means, and second setting means which refreshes the minimum value as the first set value and the maximum value as the second set value.
The present invention comprises third setting means capable of setting the set time manually.
The present invention comprises second memory means for storing the measurement time of the timer whenever the time measurement of the timer is reset, second operation mans for operating a frequency distribution of the measurement time stored in the second memory means, third operating means which operates to obtain a time T in a manner that the ratio of the cumulative frequency until the time T is the frequency distribution against the total cumulative frequency shows a certain predetermined value, and fourth setting means which executes the storing and operating operation at every fixed period thereby to refresh the setting with the time T as the set time.
In the present invention, the body movement detecting means comprises at least one piezo-electric element disposed on bedding or a seat, a filter which filters a certain specific frequency component for respective signals of the piezo-electric element, a first amplifier which amplifies the filter signal, a second amplifier having a smaller amplification than the first amplifier for amplifying the filter signal, a first rectifier which rectifies the first amplifier signal, a second rectifier which rectifies the second amplifier signal, a first smoothing device which smoothes the first rectifier signal, and a second smoothing device which smoothes the second rectifier signal, and further comprises absence judging means for judging absence of the body on the bedding when the signal level of the first smoothing device is below the first set value, presence judging means for judging presence of the body on the bed or the seat in a quiet state when the signal level of the first smoothing device is above the first set value, and the signal level of the second smoothing device is below the third set value predetermined, and body movement judging means for judging the rough body movement of the body of the bed or the seat when the signal level of the second smoothing device is above the third set value.
In the present invention, the piezo-electric element is disposed on a toilet seat or a bath tub.
Furthermore, the present invention comprises the body movement detecting means for detecting a fine movement propagated by the function of heart and breathing of a human body on a bed or a seat, said body movement detecting means producing a signal, presence judging means for judging whether or not the human body is present on the bed or the seat in accordance with the signal of the body movement detecting means.
The present invention outputs a voltage signal generated by piezo-electric effects, when at least a piezo-electric element disposed on a bed or a seat is deformed by the body movement, after filtering, amplifying, rectifying and smoothing it in the smoothing device. The present invention judges by the absence judging means that the body is absent on the bed or the seat when the signal level of the body movement detecting means is below a predetermined first set value, judges by the presence judging means, that the body is on the bed or the seat in a quiet state when the said signal level is above the first set value and below the predetermined second set value, and judges by the body movement judging means that the body has moved roughly on the bed or the seat such as turning over when the signal level is above the second set value, whereby the timer resets time measurement whenever the absence is judged or the rough body movement is judged and starts the measurement when the present in the bed or the seat is judged, and when the measurement time of the timer exceeds a predetermined set time, the sleep judging means judges that the body has fallen asleep.
In the present invention, the above-mentioned piezo-electric element is constituted by processing a high-molecular piezo-electric material such as polyvinylidene fluoride into a thin film and bonding flexible electrode films on both faces thereof to form a tape.
Also, in the present invention, the piezo-electric element is contained in a sheet shaped bag, on the portions of said sheet-shaped bag, and a stretchingly-and-shrinkingly movable stretch-shrink parts are provided on the end parts of the bag, and in addition, engaging and disengaging parts, which enable engaging and disengaging of end tip parts of said stretch-shrink parts from each other, are provided on respective ones of said end parts.
The present invention displays the signal level of the body movement detecting means by display means, and is able to change the first set value and the second set value manually in response to the signal level.
In the present invention, when the presence in bed is judged by the presence judging means, the signal level of the body movement detecting means is sampled and stored at a period predetermined; and further a minimum value and a maximum value of the memory content are operated hence to refresh the minimum value as the first set value and the maximum value as the second set value by the second setting means.
The present invention is capable of setting the set time manually by the third setting means.
The present invention stores the measurement time of the timer and operates the frequency distribution of the measurement time, every time the time measurement of the timer is reset, operates the time T in a manner that the ratio of cumulative frequency until the time T in the frequency distribution to the total cumulative frequency show a predetermined certain value, and refresh the setting taking the time T as the set time.
The present invention filters a signal of, at least, one piezo-electric disposed on the bed or the seat, amplifies the filtered signal respectively by two amplifiers having different amplifications, and rectifies and smoothes them. Then, distinguishing vibration propagated to the piezo-electric element by movement of other in the vicinity of the bed or the seat, and vibration applied to the piezo-electric element by the body movement of a person in the bed or the seat, and judging the absence, presence and rough body movement.
The present invention judges whether or not the body is present on the toilet seat or a bath tub.
Furthermore, the present invention detects the presence of the body on the bed or the seat in accordance to the signal of the body movement detecting means which detects the fine movement propagated by the function of heart and breathing of the body.

Matsushita Electric Industrial Co., Ltd.


An electrical connector includes an insulating housing having sidewalls and end walls for defining a receiving groove, a number of contacts retained in the insulating housing, the contact including a mating beam extending into the receiving groove and a retaining beam retained in the sidewall. The contact further includes a tail portion extending out of the insulating housing from the retaining beam and a soldering portion formed on a tip end of the tail portion. The soldering portion is located between a highest point and a lowest point of the contact so that the height of the electrical connector upon a PCB can be reduced, which can also reduce the mating-height of the electrical connector after mating with a mating connector.

1. Field of the Invention
The present invention relates to an electrical connector, and more particularly to a low profile electrical connector in which a terminal tail is arranged between a top and a lower surface of a housing such that the housing can sink into a printed circuit board on which it is mounted.
2. Description of Related Art
An electrical connector assembly is used in an electronic device to electrically connect with two PCBs for reducing the size of the electronic device. As disclosed in U.S. Pat. No. 6,884,089 issued to Obikane on Apr. 26, 2005, the board-to-board electrical connector assembly includes a receptacle mounted on a first PCB and a plug mating with the receptacle and mounted on a second PCB. The receptacle includes an insulating housing and a plurality of contacts retained in the insulating housing. Said contact has a horizontal base portion, a mating portion extending inward and then upwardly from inside end of the base portion, a connecting portion extending upwardly from upward end of the base portion, and a soldering portion bent horizontally from the connecting portion for being soldered on the first PCB. The first PCB defines a receiving hole for receiving the receptacle, which makes the lower portion of the receptacle located under the first PCB in order to reduce the distance between the first PCB and the second PCB after the plug mates with the receptacle. However, said connecting portion and the soldering portion of the contact are L-shaped formed, besides, a pair of sidewalls of the insulating housing abut against a peripheral edge of the receiving hole of the first PCB without a gap therebetween. As a result, during the mating process of the receptacle and the plug, if the mating direction becomes unstable under an unstable external force, said L-shaped structure of the contact will fail to provide an enough flexility to absorb the external shock, which may lead a mismating between the plug and the receptacle, and even worsely, makes the L-shaped structure broken up.
So it is necessary to provide a new electrical connector to solve the problems above.

Low profile board-to-board electrical connector having terminal tails arranged in middle of side wall


A switch device is provided. The switch device includes a circuit substrate having a fixed contact. A rubber sheet having dome-shaped protuberances is disposed on the circuit substrate. A holder is held moveable in the vertical direction. A rotatable knob is axially supported at the holder within a housing. An actuator is provided at the side of the rotatable knob. A drive portion is attached to the rotatable knob that extends out of the holder so as to be engaged with the actuator.

1. Field
The present embodiments relate to a switch device capable of selectively performing a switching operation with respect to a plurality of switch elements using the same operation member.
2. Related Art
Conventionally, a switch device has a plurality of switch elements arranged on a circuit substrate within the housing, an actuator that mounts over the plurality of switch elements, and an operation member swingable on the actuator, as disclosed in Patent Application No. H8-7701 (pp. 3-4, FIG. 1). In the conventional switch device, the operation member swingably held within the housing is partially exposed from the window portion formed in the housing so as to be operated by fingers of an operator. In response to the operation of the operation member, one end of the actuator is pushed to press the lower switch element so as to be driven. As the operation member is used to selectively push both end portions of the actuator, the switch ON signal may be selectively output from the plurality of switch elements.
The aforementioned generally employed switch device is operated by an operator for swingably turning the operation member. A multifunctinoal switch device may be formed by providing another switch element below the operation member so as to be pushed for performing various operations of the vehicle mounted devices with the same operation member in an integrated manner. However, the actuator and the switch elements activated during the swing operation are arranged below the operation member in the aforementioned switch device. When pushing the operation member, the actuator is pushed down, which is likely to cause operation error. Accordingly, it is difficult to realize the multifunctional switch device by adding the pushing operation. The structure having the actuator disposed between the operation member and the switch element similar to that of the conventional switch device may increase the height of the housing, thus causing difficulties in reducing the thickness of the entire device.

Switch device and steering switch device using the same


A booster assembly includes a booster body configured to removably couple to an actuator body of an actuator of a gate valve, a booster stem configured to removably couple to an actuator stem of the actuator, and a booster biasing member configured to provide a supplemental force to supplement an actuating force applied by the actuator to drive a gate of the gate valve from an open position to a closed position.

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Natural resources, such as oil and gas, are used as fuel to power vehicles, heat homes, and generate electricity, in addition to various other uses. Once a desired resource is discovered below the surface of the earth, drilling and production systems are often employed to access and extract the resource. These systems may be located onshore or offshore depending on the location of a desired resource. Further, such systems generally include a wellhead mounted above a wellbore through which the resource is extracted. A Christmas tree mounted above the wellhead may include a wide variety of components, such as valves, spools, and fittings that facilitate extraction, injection, and other operations. During certain operations (e.g., wireline operations), wirelines or other structures may extend through a bore of the Christmas tree toward the wellbore. Thus, certain valves of the Christmas tree may need to sever the wirelines or other structures to move from an open position to a closed position to control or to block fluid flow across the valve.


An optical amplifier having a reflector to reflect spontaneous emission light back into the amplifier, to improve excitation efficiency. More specifically, the optical amplifier includes an optical fiber and a reflector. The optical fiber is doped with a rare earth element. An excitation light is provided to the optical fiber so that a light signal is amplified as the light signal travels through the optical fiber. Spontaneous emission light is generated in the optical fiber and travels in a direction out of the optical fiber. The reflector reflects the spontaneous emission light back into the optical fiber.

This application is based on, and claims priority to, Japanese application number 10-117043, filed Apr. 27, 1998, and which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an optical amplifier which reflects spontaneous emission light back into the optical amplifier to improve excitation efficiency of the optical amplifier.
2. Description of the Related Art
Wavelength division multiplexing (WDM) is being used to increase transmission capacity of optical communication systems. With WDM, a plurality of wavelengths are multiplexed together and transmitted through a single fiber.
Moreover, in an optical communication system employing WDM, an optical amplifier can be used as a repeater. The transmission capacity of the optical communication system can be increased by expanding the gain wavelength band of the optical amplifier, to thereby increase the number of wavelengths which can be multiplexed together.
An Erbium (Er) doped fiber amplifier (EDFA) is a common optical amplifier which is widely used in optical communication systems employing WDM. In a typical EDFA, an excitation wavelength in a 1.48 xcexcm band or a 0.98 xcexcm band is used, and gain is obtained in a wavelength band which includes 1.53 xcexcm to 1.56 xcexcm (hereinafter referred to as the 1.55 xcexcm band).
However, with such an EDFA, the gain wavelength band is limited to the 1.55 xcexcm band. Thus, to realize a WDM optical communication system which can provide much larger capacity as will be required in the future, it is necessary to exploit a new gain wavelength band.
There is a known technique for realizing a gain wavelength band different from the 1.55 xcexcm band in an EDFA. In this technique, a wavelength band from 1.56 xcexcm to 1.62 xcexcm (hereinafter referred to as the 1.58 xcexcm band) is used. For example, there is reported a technique in which a gain of 25 dB is realized at a wavelength band from 1.57 xcexcm to 1.61 xcexcm, while adopting an excitation wavelength in the 1.55 xcexcm band. See, J. F. Massicott et el., ELECTRONICS LETTERS, Vol. 26, No. 20, pp. 1645-1646,27th September 1990.
Further, it has been lately reported that a gain at a wavelength band from 1.56 xcexcm to 1.62 xcexcm can be obtained by utilizing a laser diode of 1.48 xcexcm band or 0.98 xcexcm band as an excitation light source. See, H. Ono et el., IEEE PHOTONICS TECHNOLOGY LETTERS, VOL. 9, NO. 5, pp. 596-597, May 1997. This technique is advantageous in that current techniques also use a laser diode excited at the 1.48 xcexcm or the 0.98 xcexcm band, and an Erbium doped optical fiber (EDF).
The following is a brief explanation about an operational principle of 1.55 xcexcm band and 1.58 xcexcm band EDFAs. As an example of a fiber amplifier doped with rare earth element, there are considered here 1.55 xcexcm band and 1.58 xcexcm band EDFAs utilizing an excitation light source of 1.48 xcexcm band or 0.98 xcexcm band.
FIGS. 1(A) and 1(B) are diagrams showing energy levels of Erbium atom. As shown in FIG. 1(A), in a conventional 1.55 xcexcm band EDFA in which the gain is obtained between 1.53 xcexcm and 1.56 xcexcm, Erbium atom is excited by an excitation light source of 1.48 xcexcm band or 0.98 xcexcm band, and there is caused induced emission between energy levels 4I13/2 and 1I15/2. By utilizing this induced emission, there is obtained a gain at 1.55 xcexcm band.
Further, as shown in FIG. 1(B), those energy levels, which are utilized in a 1.58 xcexcm band EDFA, are also energy levels 4I13/2 and 4I15/2. For example, in a 1.58 xcexcm band EDFA, Erbium atom is excited by an excitation light source of 1.48 xcexcm band or 0.98 xcexcm band, and 1.55 xcexcm band spontaneous emission will generate and lead to amplified spontaneous emission (ASE) within a front half part of the fiber. See, H. Ono et al., TECHNICAL REPORT OF IEICE, OCS97-5(1997-05), pp. 25-30. This 1.55 xcexcm band ASE is resorbed at a rear half part of the fiber, thereby causing induced emission of 1.58 xcexcm band. In this 1.58 xcexcm band EDFA, since the cross sectional area for induced emission at 1.58 xcexcm band is smaller than that of the 1.55 xcexcm band EDFA, and since a sufficiently strong 1.55 xcexcm band ASE is to be generated, it is necessary to provide an EDF of sufficient fiber length.
However, in the aforementioned 1.58 xcexcm band optical amplifier, it is difficult to confine an excitation light or 1.55 xcexcm band ASE within the EDF efficiently, thereby resulting in a conversion efficiency which is not high.
The following is an explanation of a state of spontaneous emission which is generated within an EDF of a conventional forward excitation type 1.58 xcexcm band EDFA.
FIG. 2 is a diagram showing various lights travelling through an EDF, and FIG. 3 is an enlarged view of the EDF in FIG. 2.
As shown in FIGS. 2 and 3, an excitation light source 1A of an excitation part 1 produces excitation light Tp. Excitation light Lp is provided to EDF 2 via a WDM coupler 1B. Erbium atoms within EDF 2 are excited by excitation light Lp, so that spontaneous emission lights are generated. The spontaneous emission light generated from the Erbium atoms is composed of lights advancing in random directions, and only the lights directing into those modes, through which the lights can be propagated within EDF 2, will propagatingly advance within EDF 2. The spontaneous emission lights directing into these propagation modes will be amplified, during propagation through EDF 2 in an excited state, to become 1.55 xcexcm band ASE, and will be finally emitted from EDF 2.
Since the propagation modes should exist in both of the fore and aft directions, the 1.55 xcexcm band ASE will be emitted from both ends of EDF 2. On the other hand, those spontaneous emission lights, which do not direct into any propagation modes, will be emitted outwardly from EDF 2 via an outer surface of a cladding. In FIGS. 2 and 3, the 1.55 xcexcm band ASE in the backward propagation mode is indicated by an ASE light Lab, and the 1.55 xcexcm band ASE in the forward propagation mode is indicated by an ASE light Laf.
According to the above cited reference H. Ono et al., TECHNICAL REPORT OF IEICE, the 1.55 xcexcm band ASE, which has been generated at the front half part of EDF 2, is resorbed at the rear half of EDF 2, leading to generation of induced emission (optical amplification) at the 1.58 xcexcm band. Thus, the amount of ASE in the forward propagation mode, which is outwardly emitted from the output end of the signal light Ls, has a smaller value. However, the amount of ASE in the backward propagation mode, which is emitted outwardly from the input end of the signal light Ls, has a larger value since this mode does not contribute so much to the amplification at the 1.58 xcexcm band. Further, those spontaneous emission lights, which do not direct into any propagation modes, do not contribute to optical amplification at 1.58 xcexcm and are outwardly emitted via outer surface of cladding. As a result, a part of the energy of excitation light Lp supplied from the excitation light source 1A is wastefully consumed, thereby reducing excitation efficiency.
Meanwhile, conventional optical amplifiers aiming at improving excitation efficiency include one described in U.S. Pat. No. 5,138,483, and one described in Japanese Unexamined Patent Publication No. 3-135081. Such optical amplifiers have a configuration as shown in FIG. 4.
Referring now to FIG. 4, the optical amplifier, of which excitation efficiency has been improved, includes an excitation light reflector 4 at a rear side of EDF 2 (i.e., at an outer side of the other end opposite to an input end of excitation light Lp). Excitation light reflector 4 reflects the excitation light Lp and transmits the signal light at 1.55 xcexcm band. Via excitation light reflector 4, the excitation light Lp is reflected to make one reciprocation within EDF 2, thereby improving excitation efficiency.
Unfortunately, in an optical amplifier as illustrated in FIG. 4, only the excitation light Lp (in, for example, the 1.48 xcexcm band or the 0.98 xcexcm) is reflected by excitation light reflector 4. The 1.55 xcexcm band ASE generated
within EDF 2 will be transmitted through excitation light reflector 4. Thus, the excitation efficiency will be insufficient if the optical amplifier used to amplify signals in the 1.58 xcexcm band.
Accordingly, it is an object of the present invention to provide an apparatus in which spontaneous emission light and excitation light are effectively propagated within an active optical fiber to thereby improve excitation efficiency.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and, in part, will be obvious from the description, or may be learned by practice of the invention.
Objects of the present invention are achieved by providing an optical amplifier which includes an active optical fiber doped with a rare earth element. An excitation light generating device generates an excitation light at a predetermined wavelength band and supplies the excitation light to the active optical fiber. A spontaneous emission light reflection device reflects spontaneous emission light generated from the rare earth element excited by the excitation light and having a wavelength band different from that of the excitation light, so that a signal light is amplified as the signal light propagates within the active optical fiber. The signal light is in a wavelength band different from the wavelength band of the excitation light and the wavelength band of the spontaneous emission light.
According to such a configuration, an excitation light (such as at a 1.48 xcexcm band or a 0.98 xcexcm band) is generated by the excitation light generating device, and supplied to the active optical fiber. Within the active optical fiber, there is generated a spontaneous emission light from the rare earth element (such as Erbium) excited by the excitation light. This spontaneous emission light is propagated within the active optical fiber so as to be amplified, and thereby cause amplified spontaneous emission (ASE) at a 1.55 xcexcm band. This 1.55 xcexcm band ASE is resorbed in the course of propagation within the active optical fiber, thereby enabling optical amplification of signal light such as at 1.58 xcexcm band. Further, upon reaching the spontaneous emission light reflection device, the ASE being propagated within the active optical fiber is reflected by the spontaneous emission light reflection device, so as to be propagated in the reverse direction within the active optical fiber. By virtue of this reflection, the possibility of resorption of the spontaneous emission light is increased, so that the amplification of signal light such as at 1.58 xcexcm band can be effected at a higher excitation efficiency.
As ati example, the spontaneous emission light reflection device may include a first reflection part for reflecting the spontaneous emission light and for transmitting the signal light at a signal light input end of the active optical fiber. Further, the spontaneous emission light reflection device may include a second reflection part for reflecting the spontaneous emission light and for transmitting the signal light at a signal light output end of the active optical fiber. In addition, the spontaneous emission light reflection device may have a characteristic to transmit the excitation light, when the spontaneous emission light reflection device is provided between an output end of the excitation light generating device and one end of the active optical fiber into which the excitation light is input.
The spontaneous emission light reflection device can include the first reflection part at the signal light input end, as described above. Thus, the signal light input end of the active optical fiber is rendered to reflect ASE directing into any backward propagation mode which are difficult to be resorbed, among spontaneous emission lights generated within the active optical fiber. As a result, the ASE can be effectively utilized for amplification of the signal light. Further, by providing the second reflection part at the signal light output end of the active optical fiber, the ASE directing into any forward propagation mode is also reflected at the signal light output end, thereby enabling more effective utilization of the ASE.
Preferably, the active optical fiber is provided with, over a predetermined region along the longitudinal direction of the active optical fiber, a spontaneous emission light reflection area having a grating for reflecting the spontaneous emission light and for transmitting the signal light, and the spontaneous emission light reflection area functions as the spontaneous emission light reflection device. Concretely, the spontaneous emission light reflection area may be provided with a first reflection region arranged near a signal light input end of the active optical fiber, or a second reflection region arranged near a signal light output end of the active optical fiber.
According to such an embodiment, the ASE is rendered to be reflected by the spontaneous emission light reflection area formed within the active optical fiber. By providing the spontaneous emission light reflection area in the described manner, loss of signal light at the spontaneous emission light reflection device as well as coupling loss between the spontaneous emission light reflection device and the active optical fiber can be reduced or eliminated. Thus, the excitation efficiency is further enhanced, while enabling reduction of the noise factor.
An excitation light reflection device can also be provided at another end opposite to the one end of the active optical fiber into which the excitation light is input, for reflecting the excitation light and for transmitting the signal light.
By such an embodiment, the excitation light propagating within the active optical fiber is reflected by the excitation light reflection device, so as to go and return within the active optical fiber. As such, the excitation efficiency of the excitation light is enhanced, thereby enabling further high-powerization of the optical amplifier.
Preferably, the active optical fiber is provided with an excitation light reflection area near another end opposite to the one end of the active optical fiber into which one end the excitation light is input. The excitation light reflection area can then have a grating for reflecting the excitation light and for transmitting the signal light. As a result, the excitation light reflection area functions as the excitation light reflection device.
Thus, the excitation light is rendered to be reflected by the excitation light reflection area within the active optical fiber, so that insertion and coupling losses due to excitation light reflection device can be reduced or eliminated, thereby enabling further high-powerization of, and noise factor reduction in, the optical amplifier.
Further, with respect to the apparatus provided with the excitation light reflection device, the excitation light generating device is advantageously provided with an excitation light entrance prevention part for preventing the reflected excitation light from entering the excitation light generating device. The excitation light entrance prevention part can be an optical isolator which transmits the generated excitation light only in one direction, or an optical circulator which transmits the generated excitation light only in a certain direction between a plurality of terminals.
By providing the excitation light generating device with the excitation light entrance prevention part, there can be avoided such a situation that the operation of excitation light generating device becomes unstable due to entrance of the reflected excitation light.
In addition, with respect to any one of the aforementioned apparatuses, the active optical fiber is preferably provided with, at a surface of cladding thereof, a spontaneous emission light reflection layer for reflecting the spontaneous emission light.
By adopting such an active optical fiber, there are also confined within the active optical fiber those lights which do not direct to any propagation modes, among spontaneous emission lights generated within the active optical fiber. Thus, the excitation efficiency can be further enhanced.
The present invention further provides an active optical fiber doped with a rare earth element, including a spontaneous emission light reflection area arranged over a predetermined region along a longitudinal direction of the active optical fiber. A grating is included in the spontaneous emission light reflection area. The grating reflects the spontaneous emission light generated from the rare earth element excited by an excitation light and having a wavelength band different from that of the excitation light, and transmits a signal light at a wavelength band different from the wavelength band of the excitation light and different from the wavelength band of the spontaneous emission light.
According to such an active optical fiber, ASE directing into any propagation modes, among the spontaneous emission lights generated within the active optical fiber, can be reflected just within the active optical fiber. Thus, optical amplification at a higher excitation efficiency can be realized.
Preferably, the active optical fiber further includes, at a surface of cladding of the active optical fiber, a spontaneous emission light reflection layer for reflecting the spontaneous emission light. Thus, it becomes possible to confine ASE directing into any non-propagation modes, within the active optical fiber.
Further, an optical amplifying method is provided and which includes (a) generating an excitation light at a predetermined wavelength band; (b) supplying the excitation light to an active optical fiber doped with a rare earth element; (c) reflecting a spontaneous emission light generated from the rare earth element excited by the excitation light and having a wavelength band different from that of the excitation light, and (d) propagating, within the active optical fiber, a signal light at a wavelength band different from the wavelength band of the excitation light and different from the wavelength band of the spontaneous emission light, such that the signal light is amplified within the active optical fiber.

Optical amplifier reflecting spontaneous emission back into the amplifier to improve efficiency


A communications cable having increased fire resistance and reduced attenuation and crosstalk includes a core having at least one insulated electrical conductor, and a jacket having an inner surface and a plurality of ribs projecting radially inward from the inner surface, the ribs separated from one another by adjacent channels that extend longitudinally along the length of the cable.

Electrical cables are widely used in telecommunications applications for the transmission of voice, video and data signals. Electrical cables typically include a conductive cable core surrounded by a jacket that provides mechanical strength and protection to the cable core. PVC is commonly used as a cable insulating and jacketing material since it is cheap and, with the addition of various elastomers, can be made extremely flexible, even at lower temperatures.
However, when PVC burns it produces considerable amounts of smoke and releases toxic halogen compounds, which account for many fire-related deaths. To reduce the risk of fire propagating through a building's ductwork, safety codes often require that plenum-rated cables meet industry standards for low smoke generation and low flame spread. Cables obtain the plenum rating upon successfully passing NFPA 262 (UL 910) flame propagation and smoke generation tests, which require that the materials used in conductor insulations and cable jackets be capable of withstanding a specified amount of heat for a specified amount of time without combustion or contributing significantly to the sustenance of a fire.
To successfully achieve a plenum rating, cables are constructed of materials that are more fire resistant and produce less smoke than traditional jacket materials. While there are several versions of PVC with varying characteristics, to Applicants' knowledge none are able to pass the plenum test. Some versions of PVC and polyolefins may attain plenum capability when combined with certain other polymers that are more fire resistant. However, maintaining the safety margins against the plenum flame test is sometimes difficult. Construction must be highly controlled and, in some instances, cable designs that pass the test one time may not pass on another trial.
More successful methods for increasing flame resistance include adding halogens to the jacket material. Fluoropolymers are commonly used to increase the fire resistance of the material. The most common thermoplastic polymer in plenum cables is fluorinated ethylene-1-propylene copolymer (FEP). See, for example, U.S. Pat. Nos. 5,841,072, 5,841,073, and 5,563,377, the disclosures of which are incorporated herein by reference.
Unfortunately, fluoropolymers are much more expensive to manufacture, thus the higher cost of plenum rated cables. Furthermore, fluoropolymers are tougher and more difficult to extrude, resulting in plenum cables that are not as flexible as PVC cables. Some cables include a composite of FEP and other materials. See, for example, U.S. Pat. No. 5,932,847, the disclosure of which is incorporated herein by reference. However, these composite designs often require twist length or expansion consideration to minimize signal propagation delay skew, as well as increase manufacturing complexity and product cost.
There is also a high concern about the true safety of halogen-based cables. When halogen-based cables burn (at whatever level they produce smoke), the smoke is corrosive and contains poisonous gases. Halogen-free polymer materials require complicated self-extinguishing formulations of compounds in order to obtain low smoke cable products. These materials add cost, complexity and may degrade the electrical performance of the cable.

Jacket construction having increased flame resistance


A method of forming an epitaxial semiconductor material that includes forming a graphene layer on a semiconductor and carbon containing substrate and depositing a metal containing monolayer on the graphene layer. An epitaxial layer of a gallium containing material is formed on the metal containing monolayer. A layered stack of the metal containing monolayer and the epitaxial layer of gallium containing material is cleaved from the graphene layer that is present on the semiconductor and carbon containing substrate.

Technical Field
The present disclosure relates to semiconductor devices, such as light emitting diodes (LEDs). The present disclosure further relates to processing of materials suitable for use in LED containing structures.
Description of the Related Art
Light emitting diodes (LEDs) are well-known semiconductor devices that convert electrical current into light. The color (wavelength) of the light that is emitted by an LED depends on the semiconductor material that is used to fabricate the LED. This is because the wavelength of the emitted light depends on the semiconductor material's band-gap, which represents the energy difference between the material's valence band and conduction band electrons. Gallium-Nitride (GaN) has gained much attention from LED researchers. One reason for this is that GaN can be combined with indium to produce InGaN/GaN semiconductor layers that emit red, green, blue, and white light. This wavelength control ability enables an LED semiconductor designer to tailor material characteristics to achieve beneficial device characteristics. For example, GaN enables an LED semiconductor designer to produce blue LEDs, which are beneficial in optical recordings, and white LEDs, which can replace incandescent and halogen lamps. Despite the rapid development of GaN device technology, GaN devices can be too expensive for many applications. One reason for the high cost of manufacturing GaN-based devices is the difficulties of growing GaN epitaxial layers and of subsequently dicing out completed GaN-based devices. GaN-based devices are typically fabricated on sapphire substrates. Sapphire is an expensive material that increases the cost of LED manufacture.

Gallium nitride material and device deposition on graphene terminated wafer and method of forming the same


A printable, biaxially oriented polyolefin multilayer film which is low-temperature sealing on both sides and comprises a base layer and at least one sealing layer on each side of the base layer, the base layer containing a peroxide-degraded propylene homopolymer and each sealing layer containing an ethylene/propylene/butylene terpolymer and a propylene/butylene copolymer, one outer sealing layer containing a polydiorganosiloxane and silicon dioxide particles and not being corona-treated and the polydiorganosiloxane being added in the form of a masterbatch during the film production, results in a multilayer film especially useful as a packaging film.

The invention relates to a printable, transparent, coextruded polyolefin multilayer film which is low-temperature sealing on both sides. The multilayer film is distinguished by low film turbidity, increased scratch resistance, high surface gloss, printability, low sealing initiation temperatures (low-temperature sealing) on both sides, good slip properties, and universal usability on high-speed packaging machines. The invention also relates to a process for the production of the film and its use.
DE-A-16 94 694 discloses laminated materials which are sealable at high temperatures and comprise an oriented polypropylene film which contains at least one high-temperature sealable layer of an ethylene/propylene copolymer comprised of 2 to 6% by weight of ethylene and 98 to 94% by weight of propylene. These films have good high-temperature sealability, but they are not clear and scratch-resistant to the desired degree and, moreover, have inadequate processing characteristics on high-speed packaging machines.
EP-B-027,586 discloses sealable polypropylene films which have a sealing layer comprised of an ethylene homopolymer or copolymer, a long-chain aliphatic amine, an incompatible thermoplastic component, and a polydialkylsiloxane. These films represent an improvement over the films of DE-A-16 94 694, but they still do not run reliably on horizontal molding/filling/sealing machines.
DE-A-29 41 140 discloses a packaging material which is comprised of a base layer of a polypropylene polymer and of a surface layer which comprises a mixture of a propylene/ethylene copolymer and a (C.sub.4 -C.sub.10)-.alpha.-olefin/propylene copolymer. This surface layer can also contain a thermoplastic resin of low molecular weight, as well as silicone oils. A disadvantage of packaging materials of this type is that they are susceptible to scratching and have unsatisfactory optical characteristics.
EP 114,312 discloses a transparent polyolefin multilayer film, which is comprised of a base layer of a propylene polymer and at least one sealable layer. The sealable layer comprises an olefin resin composition, an ethylene/propylene/butylene polymer and a propylene/butylene polymer and contains 5-15% by weight of a compatible hydrocarbon resin, 5-15% by weight of propylene homopolymer and 0.3-1.5% by weight of polydiorganosiloxane. The film has a low sealing initiation temperature and runs reliably on high-speed packaging machines. However, the film is not printable. Moreover, because of the addition of resin, resin deposits are formed on the longitudinal drawing rollers during film production and this has an adverse effect on the optical characteristics of the film caused by striation. When Example 1 of EP 114,312 was repeated, it was also found that the film had deficiencies in frictional characteristics and poor optical characteristics including high turbidity and low gloss. Moreover, flow defects arise over the film width, which lead to a high rejection rate.
Furthermore, in their brochure TAFMER XR, Japan 82 03 1000 Cl, Mitsui Petrochemical Industries Ltd. describe an .alpha.-olefin copolymer which is suitable as a sealing layer for polypropylene films. However, as Comparison Example 8 of this application shows (see Table 1), polypropylene films provided with this sealing layer are not satisfactory in various respects.
None of the known multilayer films simultaneously meets the criteria which are important for a packaging film, i.e., low sealing temperature on both sides in combination with the following characteristics: printability, high surface gloss, low turbidity, homogeneous film optical characteristics (no striations, no flow defects), low susceptibility to scratching, good frictional characteristics and good running characteristics on high-speed packaging machines of various types.

Printable, biaxially oriented polyolefin multilayer film


A clean room ceiling structure includes a support structure and filter units with a filter frame and a filter secured in the filter frame. The filter frames are connected to the support structure. The filter units have sealing fluid grooves for sealing the filter units relative to the support structure.

The present invention relates to a clean room ceiling structure, preferably a modular ceiling structure, comprising a support structure having arranged thereat filter units comprised of filters and filter frames which are supported at holders of the support structure and are sealed relative to the support structure by at least one fluid groove.
Known-modular ceiling structures of this kind are comprised of rails and connecting elements or coupling members. The rails have connected thereto the filter/fan units. For sealing the filter units relative to the support structure, the rails are provided with fluid grooves into which extends a sealing stay of the filter frame. This embodiment has the disadvantage that the width of the rails is relatively large which, in turn, results in the effective filter surface area being reduced. Furthermore, due to the large width stronger turbulence may occur within the clean room. In order to reduce turbulence locally, it is therefore suggested to provide perforated sheet metal plates below the filter units and arrange them such that they are flush with the ceiling structure. Illumination for the modular ceiling structure is integrated into the rail of these known modular ceiling structures. This also results in the width of the rails being large so that the effective filter surface area is reduced.
Other modular ceiling structures are known in which the illumination or lamps are provided within the clean room at the support structure of the ceiling, i.e., the lamps are suspended from the ceiling structure. This reduces the usable height of the clean room.
It is therefore an object of the present invention to provide a clean room ceiling structure of the aforementioned kind such that a widened embodiment of the support structure, caused by the fluid groove and by an optionally provided lamp, is prevented.


A total internal reflection (TIR) modulator includes a member comprising an electro-optic material; a plurality of first electrode sets; a plurality of second electrode sets; and a first set of electrical conductors, each electrical conductor in the first set of electrical conductors being coupled to one of the second electrode sets wherein the electrodes in each second electrode set are arranged in an interdigitated relationship with the electrodes in one of the first electrode sets; and each of the first electrode sets comprises a first electrode, the first electrodes being arranged in an interdigitated relationship with the electrical conductors in the first set of electrical conductors.

Electro-optic materials are those whose optical properties change in accordance with the strength of an electric field established within them. These materials make possible an electrically controlled electro-optic modulator for use in a light valve array.
One well known form of electro-optic modulators are total internal reflection (DR) modulators which can be employed in laser-based imaging systems for example. FIGS. 1A and 1B schematically show plan and side views of a conventional TIR modulator 10 comprising a member 12 which includes an electro-optic material and a plurality of electrodes 15 and 16 arranged in an interdigitated relationship on a surface 18 of member 12. Surfaces 20 and 22 are arranged to cause input radiation 25 to refract and undergo total internal reflection at surface 18.
In this typical conventional configuration, various electrodes 15 and 16 are grouped into electrode groups S1, S2, S3, S4 . . . Sn which are collectively referred to as electrode groups S. Each of the electrodes 15 in each of the groups are driven with a corresponding one of individually addressable voltages sources V1, V2, V3, V4 . . . Vn which are operated in accordance with various image data signals. To simplify interconnect and driver requirements, all electrodes 16 are interconnected to a common source (e.g. a ground potential). In this case, electrodes 16 are coupled in a serpentine fashion among all the electrode groups S.
Upon the application of a suitable voltage by one of the voltage sources V1, V2, V3, V4 . . . Vn to an associated one of the electrode groups S1, S2, S3, S4 . . . Sn, an electric field is established in a portion of the of the electro-optic material referred to as a pixel region 11 (i.e. shown in broken lines). In this regard, an electrode group S is associated with each pixel region 11. FIG. 1B shows that each pixel region 11 includes a portion of surface 18 that is impinged by radiation 25.
The application of the voltage alters the refractive index of the electro-optic material, thereby changing a birefringent state of the pixel region 11. Under the application the corresponding drive voltage, the arrangement of electrodes 15 and 16 in each of the electrode groups S1, S2, S3, S4 . . . Sn causes each of the electrode groups to behave in a manner similar to a diffraction grating. A birefringent state of each of the pixel regions 11 can therefore be changed in accordance with the selective application of various voltages by an associated one of voltage sources V1, V2, V3, V4 . . . Vn. For example, in this case when no voltage is applied to a particular electrode group S, an associated pixel region 11 assumes a first birefringent state in which output radiation 27 is emitted from surface 22 and is directed by one or more lenses (not shown) towards a surface of a recording media (also not shown) to form an image pixel thereon. In the case when a suitable voltage is applied to a particular electrode group S, the associated pixel region 11 assumes a second birefringent state in which output radiation 27 is emitted from surface 22 in a diffracted form which can be blocked by an obstruction such as an aperture (also not shown) to not form an image pixel.
Various image features are formed on a recording media by combining image pixels into arrangements representative of the image features. It is a common desire to form high quality images with reduced levels of artifacts. In particular, the visual quality of the formed image features is typically dependant on the visual characteristics of the formed image pixels themselves. For example, one important characteristic is the contrast between an image feature and surrounding regions of the recording media. Poor contrast can lead to the formation of various image features whose edges lack sharpness or are otherwise poorly defined. Another important characteristic is the accurate placement of the image pixels on the recording media.
The previously described conventional method of driving the arrangement of electrodes 15 and 16 can lead to various problems which can adversely impact a desired visual characteristic of the final image. For example, the sharpness of feature edges can suffer or an undesired deflection of output radiation 27 can arise. FIG. 1C schematically shows a subset of electrode groups S1, S2, S3, and S4 driven with various voltage levels by their corresponding voltage sources as follows: (V1: V); (V2: V); (V3: 0); and (V4: V). Voltage level "V" corresponds to a drive voltage level selected to cause substantial diffraction to be created within a pixel region 11 whereas voltage level "0" corresponds to a voltage level (i.e. a ground potential in this case) selected to not cause substantial diffraction to be created within a pixel region 11. When a pixel region 11 is made non-diffracting (e.g. the pixel region 11 corresponding to electrode group S3), the average electric potential of the electrodes 15 and 16 of the pixel region is null. However, when a pixel region 11 is made diffracting (e.g. the pixel regions 11 corresponding to electrode groups S1, S2 and S4) the average electric potential of the electrodes 15 and 16 of the pixel region 11 is approximately V/2. This creates an electric potential difference of V/2 between the average voltages of non-diffracting and diffracting regions of TIR modulator 10. This can give rise to long-range electric fields that deflect radiation that is propagated within the electro-optic material to produce a beam steering effect. Although the long-range fields can be relatively weak, they typically interact with the radiation over a longer path length than the shorter range diffraction grating fields. TIR modulator 10 is an example of an "unbalanced" TIR modulator.
One possible consequence of this deflection is that image pixels formed on the recording media can be shifted and a placement error arises. The degree of the placement error can vary in accordance with the image data which controls the selective application of the drive voltages. Another possible consequence can include an increase in the diffraction broadening of an image pixel since the output radiation 27 is deflected to one side in the pupil of the imaging system, thereby reducing the effective aperture of the system. Other possible consequences can include an increased sensitivity to aberrations in the imaging system.
Commonly-assigned U.S. Pat. No. 7,656,571 B1 (Reynolds) describes a total internal light modulator in which potential differences between diffracting and non-diffracting regions of the modulator are balanced. FIGS. 2A and 2B schematically show corresponding plan and side views of a TIR modulator 100 similar to a modulator described in U.S. Pat. No. 7,656,571. TIR modulator 100 includes a member 112 comprising an electro-optic material 113. A plurality of electrodes 115 and 116 are arranged on a surface 118 of member 112. Member 112 includes surfaces 120 and 122 which are arranged to cause radiation 125 to refract and undergo total internal reflection at surface 118.
As shown in FIG. 2A, each of the electrodes 115 and 116 is elongate in form and extends along a direction that is substantially parallel to an overall direction of travel 126 of radiation 125. As shown in FIG. 2A, electrodes 115 are arranged in a plurality of first sets while electrodes 116 are arranged in a plurality of second sets. Each set of electrodes 115 is electrically driven by a corresponding one of individually controllable first voltage sources: VJ1, VJ2, VJ3, VJ4 . . . VJn (i.e. collectively referred to as first voltage sources VJ) via a corresponding one of a plurality of electrical conductors 128A arranged on surface 118. Each set of electrodes 116 is electrically driven by a corresponding one of individually controllable second voltage sources: VK1, VK2, VK3, VK4 . . . VKn (i.e. collectively referred to as second voltage sources VK) via a corresponding one of a plurality of electrical conductors 128B arranged on surface 118. In this case, each of the first voltage sources VJ is coupled to an associated one of the electrical conductors 128A at an interconnect element 130A provided on surface 118. In this case, each of the second voltage sources VK is coupled to an associated one of the electrical conductors 128B at an interconnect element 130B provided on surface 118. Each of the electrical conductors 128A and 128B acts as feed line between associated interconnect elements and electrode sets. FIGS. 2A and 2B show that each of the electrical conductors 128A extends over a non-pixel region 132A and that each of the electrical conductors 128B extends over a second non-pixel region 132B. As shown in FIG. 2B, neither of non-pixel regions 132A and 132B includes a portion of surface 118 that is impinged by radiation 125. Pixel regions 110 and non-pixel regions 132A and 132B are each shown in broken lines in FIG. 2A.
Each set of electrodes 115 is arranged with a set of electrodes 116 such that their respective electrodes are interdigitated with respect to one another within an associated one of electrode groups T1, T2, T3, T4 . . . Tn (i.e. collectively referred to as electrode groups T). As shown in FIGS. 2A and 2B each electrode group T is associated with one of a plurality of pixel regions 110 that are directly impinged by radiation 125.
FIG. 2C schematically shows a subset of the electrode groups T (i.e. electrode groups T1, T2, T3, and T4) of light modulator 100 driven by their corresponding voltage sources VJ and VK to establish various electric potentials on each of the sets of electrodes 115 and 116 associated with each of the electrode groups T. In particular, FIG. 2C shows that electrode groups T1, T2, T3, and T4 are driven by corresponding voltage sources VJ and VK as follows: (VJ1: +V/2, VK1: −V/2), (VJ2: +V/2, VK2: −V/2), (VJ3: 0, VK1: 0), and (VJ4: +V/2, VK4: −V/2). The voltages combinations of "+V/2" and "−V/2" correspond to drive voltages that are applied to an electrode group T to cause substantial diffraction within a pixel region 110 associated with the electrode group T. In this regard, a difference of V Volts between these two potentials is sufficient to cause the diffraction. The voltage combinations of "0" and "0" correspond to drive voltages that are applied to an electrode group T to not cause substantial diffraction within a pixel region 110 associated with the electrode group T. In this regard a difference of 0 Volt is insufficient to cause diffraction.
In this case, TIR modulator 100 is driven such that the averages of the voltage combinations used to create each of the different birefringent states in a pixel region 110 are substantially equal to one another. That is, the average voltages used to create a substantially non-diffracting state in a pixel region 110 (i.e. the average of 0 Volt and 0 Volt) substantially equals an average of the voltages used to create a substantially diffracting state in a pixel region 110 (i.e. the average of +V/2 Volts and −V/2 Volts). FIG. 2C schematically shows the average electric potentials imposed on the electrodes 115 and 116 of electrode groups T1, T2, T3, and T4 in this case. Unlike the aforementioned TIR modulator 10 in which a variance of V/2 Volts existed between the average electrical potentials of the non-diffracting and diffracting pixel regions 11 of TIR modulator 10, such variances are reduced in the TIR modulator 100. TIR modulator 100 is an example of a "balanced" TIR modulator.
It has been noted by the present inventors that other electrically conductive members (i.e. other than the interdigitated electrodes) can also generate electric field within an elector-optic material of a light modulator. In case of the TIR modulator 100, the present inventors have noted that a set of electrical conductors (e.g. the set of electrical conductors 128A or the set of electrical conductors 128B) can lead to the creation of an electric field. It has been noted that the electric field created by set of electrical conductors 128A or 128B typically penetrates more deeply into electro-optic material 113 than an electric field created by the electrodes in an electrode group T. This effect is simulated in FIG. 2B where an electric field 136 is generated by various electrical conductors 128A and an electric field 138 is generated by various electrical conductors 128B. Each of the generated electric fields 136 and 138 penetrate member 112 in the vicinity of non-pixel regions 132A and 132B, respectively. Although the electric fields 136 and 138 are associated with non-pixel regions 132A and 132B that include portions of surface 118 that are not directly impinged by radiation 125, electric fields 136 and 138 penetrate sufficiently within the electro-optic material 113 to interact with radiation 125. Electric fields 136 and 138 can lead to various problems including undesired beam steering of the radiation 125 that is outputted from TIR modulator 100.
There is a need for improved TIR modulators that can further reduce beam steering effects.
There is a need for improved balanced and unbalanced TIR modulators that can further reduce beam steering effects.


A method of calculating torque of a Lundell-type synchronous generator is disclosed in which only power generation output current and a rotational speed are input for calculation of the amount of electric power and the amount of losses for thereby enabling calculation of power generating torque, based on a sum of the amount of electric power and the amount of losses, which is generated as an output. The present method establishes formulae enabling calculation based on only output current and the rotational speed, enabling a minimal number of inputs to shorten a calculation time interval.

1. Technical Field of the Invention
The present invention relates to a method of calculating power generating torque of a synchronous generator, especially, a vehicular Lundell-type synchrounous generator.
2. Description of the Related Art
In recent years, attempts have heretofore been made to reduce the amount of fuel, such as gasoline, to be injected into an engine with a view to achieving the improvement in fuel consumption. To this end, the engine is controlled in a pinpoint precision to rotate in stability. In the meanwhile, an electric energy needed for the engine for safety and comfort purposes is rising year to year and a generator (alternator), connected to the engine, has been increasing in size. This results in an issue with the occurrence of an increase in torque of the generator accompanied by instable rotation of the engine. For instance, under circumstances where large electric load is turned on to rapidly increase the electric energy of the generator, a drop occurs in a rotational speed of the engine with a consequence of engine stop.
To address such an issue, research and development work has heretofore been taken to provide technique of conducting integrated management of electrical loads through the use of a communication system inside the vehicle for predicting power generating torque to control the amount of fuel to be injected to the engine with a view to achieving stability in engine rotation.
However, even if the related art practice has enabled the prediction of the amount of generated electric power (electric current in generated electric power), a difficulty has been encountered in accurately calculating power generating torque on this occasion. Power generation torque represents a turning force equivalent to energy to be consumed. In this case, energy to be consumed is a sum of generated electric power and the amount of loss dissipated in heat. For example, even with output currents at the same value, variation takes place in a coil resistance value depending on surrounding temperatures with the resultant change in heating value. Thus, a need arises for accurately obtaining the amount of losses of the generator depending on an operating status of the generator and usage environment thereof, otherwise no success can be expected in calculating power generating torque.
Further, the amount of losses of the generator is broken down into copper loss, rectification loss, excitation loss, iron loss and mechanical loss. Among these, iron loss particularly consumed in an iron core results from hysteresis loss and eddy-current loss in mixture and, hence, a calculation formula becomes complex with the resultant difficulty in identifying the cause of losses. This results in deterioration in precision of calculation results. Moreover, a remarkable increase occurs in a time interval needed for calculation and it has been conceived that no computation of such factors is possible with a computer Installed on the vehicle.
Therefore, attempts have taken to preliminarily assume the environment for the generator to be used and prepare a map covering a whole range of conceivable combinations of factors while actually measuring parameters such as temperatures or the like and retrieving target torque from the map. However, this results in a need for preparing torque data in a multidimensional approach in conformity to various statuses and, thus, considerable efforts are needed for measurements. This causes a remarkable increase in a volume of data with the resultant increase in a retrieving time interval and another issue arises in a difficulty of processing these data in an ECU. Moreover, a large number of sensors are needed for measuring input values of the parameters and cause an increase in production cost. Also, if the volume of data and the amount of inputs are restricted, then, another issue arises with a difficulty in obtaining high precision.

Method of calculating power generating torque of synchronous generator


A wire terminal structure capable of fully enclosing internal components to prevent external dust or impurity from entering the insulation case to affect the normal operation thereof. The wire terminal structure includes an insulation case and a conductive holding frame disposed in the case. The case is formed with a wire socket and a press window. The conductive holding frame has an elastic holding member corresponding to the wire socket. The elastic holding member is formed with a holding mouth. A push section is disposed on the elastic holding member corresponding to the press window. A pushbutton is elastically movably disposed in the press window between the press window and the push section. The pushbutton is spaced from the case. When an external force is applied to the pushbutton, the pushbutton is elastically moved to push the push section and open the holding mouth.

1. Field of the Invention
The present invention relates generally to an improved wire terminal structure, and more particularly to a wire terminal structure for the wire connected to an electronic component such as an LED. The wire terminal structure is capable of fully enclosing internal components to prevent external dust or impurity from entering the insulation case to affect the normal operation thereof.
2. Description of the Related Art
A wire terminal or so-called connector is used to connect the metal conductive wires (electrical wires) between electronic components or connect the conductive wires between electronic components and circuit board. The electronic components can be a resistor, a capacitor, an inductor, an LED, a transformer, a liquid crystal panel, a touch panel or the like. The wire terminal serves to transmit power or electronic signal to facilitate the installation and layout of the internal circuit board and electronic components of an electronic product or apparatus.
Currently, there are various wire terminals on the market. In general, the conventional wire terminal has an insulation case and multiple conductive holding frames enclosed in the insulation case. The conductive holding frame is made of conductive metal material, having several elastic holding members for holding the wires of external electronic components and several soldering pins exposed to outer side of the case. The wire terminal is soldered on a circuit board via the soldering pins. In addition, the case is formed with a wire socket. The wire of the external electronic component can be plugged through the wire socket into the case and clamped by a holding mouth of the elastic holding member.
In order to easily extract the wire from the holding mouth of the elastic holding member of the wire terminal for replacement of the circuit board or electronic component or maintenance/reparation of the electronic product or apparatus, the elastic holding member of the wire terminal is formed with a push section for elastically opening the holding mouth so as to release the wire. For example, a conventional skill discloses a control device for electrical wire holder. The electrical wire holder (the elastic holding member of the conductive holding frame) has a slide aid slope (the push section) for elastically opening the electrical wire holder to release the external wire. A press arm is integrally formed on the insulation case corresponding to the slide aid slope. In use, a force is applied to an outer side of the press arm to inward elastically bend the press arm to touch the slide aid slope. At this time, the electrical wire holder is elastically forcedly opened in a direction reverse to the holding force. Thereafter, the wire can be easily extracted out of the case.
However, according to said conventional skill, the press arm is integrally formed on the insulation case and the stress is likely to concentrate on the bending junction between the press arm and the insulation case. The insulation case is generally made of plastic material so that the press arm is very likely to break. Therefore, the reliability and durability of such wire terminal are poor.
Moreover, when the press arm is pressed with a force, the press arm needs to elastically swing to touch the slide aid slope. In the precondition that the press arm is integrally formed on the insulation case, a gap obviously exists between the press arm and the insulation case so that the insulation case will not interfere with the press arm when elastically swinging. When the press arm is integrally formed on the insulation case by means of in-mold injection molding, the gap is naturally formed between the press arm and the insulation case. As a result, the external dust, impurity and moisture are very likely to go through the gap into the insulation case to affect the normal operation of the wire terminal and shorten the lifetime thereof.


In a nitride semiconductor based bipolar transistor, a contact layer formed so as to contact an emitter layer is composed of n-type InAlGaN quaternary mixed crystals, the emitter layer and the contact layer are selectively removed so that the barrier height with the emitter formed thereon is small, and the ohmic electrode contact resistance can be lowered on the InAlGaN quaternary mixed crystals, for example, so that a WSi emitter electrode becomes an eave. A base electrode is formed by a self-aligned process using the emitter electrode as a mask. By such a configuration, the distance between the emitter and the edge of the base electrode is sufficiently shortened, and the base resistance can be lowered. As a result, a bipolar transistor having favorable high-frequency characteristics can be realized.

A nitride compound semiconductor represented by a GaN compound semiconductor is known as a wide-bandgap semiconductor wherein the bandgap of GaN is as large as 3.4 eV at room temperature. Since such a semiconductor has higher saturation velocity and breakdown electric field than that of the other semiconductors, such as GaAs, and Si semiconductors. The nitride compound semiconductor is expected for high-frequency and high-power electronic devices. It is one of features of a GaN based semiconductor that internal field is formed by spontaneous polarization and piezo polarization in a direction perpendicular to the formed (0001) face, and in an AlGaN/GaN hetero structure, a sheet carrier concentration of at least 1×1013 cm−2 is obtained in an undoped state. A hetero junction field effect transistor (HFET) utilizing these features has been fabricated using two-dimensional electron gas in the hetero interface, and the excellent high-frequency operation thereof has been reported. As described above, GaN based transistors heretofore reported are mainly planar field effect transistors. To realize further high-speed operation, a vertical bipolar transistor that can shorten carrier transit time is more promising than a planar transistor. In existing GaN planar field effect transistors, negative bias must be supplied to the gate electrode and positive bias must be supplied to the drain electrode, for which both positive and negative voltage power sources are required. Therefore, the downsizing of, for example, radio communication systems is difficult; however, since a bipolar transistor requires only a positive voltage power source, the downsizing of the systems becomes feasible. Heretofore, there has been reported that high-gain and high-frequency characteristics of a conventional compound semiconductor represented by GaAs can be improved by a hetero junction bipolar transistor (HBT) wherein the hereto junction is formed between the base and the emitter. In also GaN based semiconductors, it is considered that further high-speed transistors can be realized by forming HBTs in the same manner as in conventional compound semiconductors.
An example of heretofore reported GaN based HBT structures will be described below. An AlN buffer layer, an n-type GaN sub-collector layer, an n-type GaN collector layer, an n-type InGaN layer having an In component gradient layer, an Mg-doped p-type InGaN base layer, and an n-type GaN emitter layer are formed in this order on an SiC substrate. A step is formed in the n-type emitter layer, an Al/Au electrode to be an emitter electrode is formed thereon, a Pd/Au electrode to be a base electrode is formed on the exposed p-type InGaN base layer, and an Al/Au electrode to be a collector electrode is formed so as to contact the n-type GaN sub-collector layer. The feature of the GaN based HBT structure is that the activation of the dopant Mg is improved, and the base resistance which is an important factor to determine high-frequency characteristics is lowered by the InGaN base layer, in place of GaN. In the present situation, a current amplification of 20, which is one of the largest in GaN based HBT, can be realized.

Nitride semiconductor based bipolar transistor and the method of manufacture thereof


A music playing data fetch circuit for a personal computer which is capable of improving a music playing operation using a CPU of a personal computer by using a 64-bit FIFO memory without using an interrupt signal. The circuit includes a sound interface controller for receiving a serial playing data from a music playing program from a central processing unit (CPU) of a personal computer (PC), a midi (musical instrument device interface) interface controller for fetching a serial playing data from the sound interface controller and generating tone, waveform, etc. by enabling an interrupt request signal, and a buffer for buffering a data from the sound interface controller when the personal computer requests the data transmitted to the midi interface controller.

1. Field of the Invention
The present invention relates to a music playing data fetch circuit for a personal computer, and in particular to an improved music playing data fetch circuit for a personal computer which is capable of reducing the operational time of an operating system of a personal computer by fetching a serial playing data of a music playing program, and reducing a chip size by transmitting and receiving a midi data by using only a receiving channel of a universal type asynchronous transceiver.
2. Discussion of Related Art
FIG. 1 illustrates a conventional sound card circuit for a personal computer using a music playing program.
As shown therein, the conventional sound card circuit includes a CODEC 10 for receiving a musical instrument device interface (MIDI) signal from a central processing unit (CPU) of a personal computer, converting the thusly received signal into a digital midi data, a tone Read Only Memory (ROM) 30 for storing a tone data, a sound Integrated Circuit (IC) 20 for generating and outputting a tone corresponding to the tone data inputted, a micro-program control unit 40 for performing a stored micro-program in accordance with a midi signal from the CODEC 10, a program ROM 50 for storing a program code which is used when performing a micro-program of the micro-program control unit 40, a random access memory (RAM) 60 for storing a data which is used for performing the micro-program, and a modulation IC 70 for generating a sound wave form which forms a sine wave form.
The operation of the conventional sound card circuit will now be explained with reference to FIG. 1.
First, when a midi signal for requesting to play "Do" in piano is inputted from the CPU of the personal computer, the CODEC 10 receives the signal, converts the signal into a digital midi data, and transmits to the micro-program control unit 40.
The micro-program control unit 40 performs a micro-program, and analyzes an inputted midi data.
A tone data corresponding to "Do" is outputted from the tone ROM 30, and a predetermined tone corresponding thereto is generated by controlling the sound IC 20, and a wave form corresponding thereto is formed by controlling the frequency modulation IC 70 and then the tone signal is transmitted to the CODEC 10.
The CODEC 10 converts the data corresponding to the tone and wave form generated by the micro-program control unit 40 into an analog signal.
The program code which is used at the time when the micro-program control unit 40 performs a microprogram is read from the program ROM 50, and the RAM 80 temporarily stores and outputs the data.
However, the conventional sound card circuit has a problem in that if each function of the system is performed by using sound card circuits, the chip size is made bulky.
In order to overcome the above-described problem, the micro-program control unit 40, the program ROM 50, the RAM 60, and the frequency modulation ID 70 are operated based on the software and the CPU of the personal computer.
Namely, since the CPU has a multi-task function for concurrently performing a music or a game such as a cake walk, it is possible to process a serial midi data based on the software.
Therefore, the CODEC 10, the sound card IC 20, and the tone ROM 30 are configured as shown in FIG. 1, and the functions of the remaining elements are performed based on the software.
However, in the conventional sound card circuit, since the serial playing data of the music playing program is fetched based on the software, the sound card circuit is operated much more dependently to the operating system of the personal computer. Therefore, there may be computer programs which are not operated under DOS, Windows 3.1, and Windows 95. In addition, the software should be independently programmed with respect to each controller of the system.


An outboard motor includes a transmission device disposed on a middle portion of a drive shaft driven by an engine. The transmission device includes a forward-reverse switching device housed in a transmission case. Lubricating oil for lubricating the forward-reverse switching device is stored in the transmission case. The transmission case has a drain hole arranged to discharge lubricating oil in the transmission case that is provided in a lower portion of a side wall and in a position in front of the drive shaft, and a drain bolt for opening or closing the drain hole. An exposed opening for exposing the drain hole is provided in an upper case that covers the transmission case. As a result, work efficiency in discharging or draining of lubricating oil is greatly improved without requiring dismantling of a main body of the outboard motor.

1. Field of the Invention
The present invention relates to an outboard motor, in particular, an outboard motor with an improved drain construction for lubricating oil.
2. Description of the Related Art
Conventionally, an outboard motor disclosed in WO 2007-007707A1 includes a power transmission system provided on a middle portion of a drive shaft to transmit power of an engine to a propeller. The power transmission system has a speed changer constructed with a planetary gear mechanism.
Accordingly, the speed of power from the engine is changed by the speed changer, and the power is transmitted to the propeller. Thereby, the propeller rotates at a prescribed speed.
However, in such a conventional outboard motor, the speed changer and so forth of the power transmission system requires lubrication with lubricating oil. Further, the lubricating oil is required to be changed.