A media content service is distributed across a distribution network. A plurality of media content service representations (80A, 80B) for the media content service are generated. Each of the media content representations (80A, 80B) has a different bit rate. Each of the media content service representations (80A, 80B) is divided into segments (81A, 81B). Segments (81A, 81B) of the plurality of media content service representations are aligned in time. The segments are transmitted as a sequence of bursts (82A, 82B). The bursts of the plurality of media content service representations are aligned in time. There is a window period (83) between successive bursts during which media content is not transmitted. Each of the media content service representations is transmitted as a multicast. Each of the generated media content service representations (80A, 80B) has a respective bit rate and each of the segments (81A, 81B) is transmitted at a higher bit rate to create the window periods (83) between successive bursts (82A, 82B).

Traditional telecommunications systems have evolved rapidly in recent years to encompass considerably more capability than simply delivering a telephony service. Internet technology based on data packets and associated transmission protocols, for example the Internet Protocol (IP), has now superseded the old space switching techniques and dedicated transmission resources during a telephone call or data transmission session.
The convergence of flexible delivery technologies has enabled services to be mixed in the same physical resource so that for example, in telephony networks, subscribers are now able to receive audio-visual content, including relayed broadcast television and radio services, as well as access internet resources, all via their telephone lines. Similarly, the expansion of wireless networks have enabled a user to receive a range of communications services over a wireless delivery channel.
A Digital Subscriber Loop (xDSL) modem/router, which is widespread in homes, acts as a common assembly point for all domestic communications traffic, such as telephony, computer-based web browsing, email, home shopping or streaming of video material. As will be appreciated by a skilled person, the capacity of the digital subscriber loop has to be shared among the services being provided to the subscriber at any particular time.
There is considerable interest in receiving "streamed" services which deliver a stream of video and/or audio material to users. The content can be live content or it can be recorded content which is requested on demand. In an Internet Protocol Television (IPTV) system, video and audio content is delivered to users via Internet Protocol (IP) delivery mechanisms. These types of services require a continuous and uninterrupted flow of data. A premises may have multiple terminals which are capable of receiving media content. The demands placed on the delivery channel can vary according to how many terminals require content at a particular time.
Streamed media content services can be provided by one of two methods: Unicast or Multicast. Unicast provides the subscribing receiver with a direct and unique two-way path through the delivery network all the way back to the media server supplying the required data stream. The main streaming activity is managed on a one-to-one basis between the receiver and the source server. The network between the source server and receiver typically comprises a series of intermediate servers installed at network nodes which are not directly involved in the service but only support the transfer of a packet stream. Typically the protocols used to support the transmissions are simple forms of Internet Protocol (IP) itself augmented by one or more higher layer protocols to provide flow control. These protocols extend across the span of the link between the source server and a given receiver. This method of distribution is wasteful of network capacity because, at busy times and for popular media streams, many copies exist in the network simultaneously and this contributes to network congestion.
A Unicast system can support Adaptive Bit Rate Streaming (ABR). This allows some form of rate adaptation. A given service is encoded at a selection of different bit rates (known as representations), with synchronised boundary points at defined locations (e.g. every 50 frames). For each representation, content between successive boundary points is converted into a discrete file. Clients fetch a segment of one of the representations in turn. If a higher or a lower bit rate is required, the next segment is fetched from one of the other representations. The segments are constructed such that there is no discontinuity in decoded pictures/audio if the client switches between representations at the boundary points. This system requires the unicast two-way path between source and receiver to request files and deliver the requested files.
Multicast makes more efficient use of bandwidth by sharing content streams among several receivers. Intermediate network routers are now more closely involved in the service delivery such that some control and management functions are delegated from the source server. This control is supported by more extensive protocols devised for this type of application such as Protocol Independent Multicast (PIM) and Internet Group Multicast Protocol (IGMP). When a new receiver requests a given media item, the network router system finds an existing stream of that content already in the network and directs a copy of it to that new receiver from an appropriately near network node. A new receiver has to be able to join this existing stream under controlled conditions that do not adversely affect existing receivers. Any receiver in this group also has to be able leave the stream, or pause its consumption, without affecting the others. There is now a clear separation of control and management from the content. This complicates the control function because several receivers will have different instantaneous bit rate and control needs and so the segmentation of the stream as it passes through a given network has to deal with the conflicting demands. These are managed directly between the receiving device itself and the nearest upstream router/server that will mediate control functions including any need to refer back to earlier network servers or even the original source server.
Currently, each TV service has to be set up with a conservative configuration. This can be a capped Variable Bit Rate (VBR) with a safe cap value. This is because it is not possible to change bit rate of a service on the fly without interrupting the TV service.
In summary, while unicast systems can support an adaptive bit rate of a streamed service over time, this comes at a significant cost in terms of resources of the delivery network to support a large number of unicast paths, and may require additional servers located near to clients of the network to maintain acceptable response times. Multicast systems can more efficiently use bandwidth resources of the network, but do not support adaptive bit rate needs of client devices.
The present invention seeks to provide an alternative way of distributing media content services, such as video services.

Method and apparatus for distributing a media content service


An apparatus for transferring solid materials between zones of substantially different pressures, the solid materials being supplied to a lockhopper containing a liquid having a density less than the solid materials, the solid materials with associated liquid passing through a solids-liquid separator chamber separating the solid materials and liquids so that the solid materials, substantially free of liquids, are passed into a vessel such as a pressurized reaction vessel.

1. Field of the Invention
This invention relates to an apparatus for transferring solid materials between zones of substantially different pressures, the solid materials being supplied to a lockhopper containing a liquid having a density less than the solid materials, the solid materials with associated liquid passing through a solids-liquid separator chamber separating the solid materials and liquids so that the solid materials substantially free of liquids, are passed into a vessel such as a pressurized reaction vessel. The liquid in the lockhopper acts as a liquid seal between the pressurized reaction vessel and lockhopper which is at a much lower pressure. Utilization of the solids-liquid separator chamber provides more rapid recycling of the lockhopper, prevents liquid from being carried into the reactor vessel if there is a pressure surge and allows handling finer solid materials.
2. Description of the Prior Art
Several methods utilizing different apparatus have been used in the past for the introduction of solids into pressurized reactors. Gas pressurized lockhoppers have been used for transferring solids into a pressurized reactor. Solids are added to a lockhopper at ambient pressure and the lockhopper closed and pressurized with gas to the pressure of the reactor. The solids are then added to the reactor which is at about the same pressure as the lockhopper. The lockhopper must then be isolated from the reactor and reduced to ambient pressures for introduction of the solid materials. Gas pressurized lockhoppers require complicated valving and in practice, have long cycle times.
Lockhoppers are frequently constructed in the form of a long gravity feed leg above the reactor to overcome the pressure differential and thus are feasible over relatively small pressure differentials in the order of about 10 psi, due to the high pressure legs required. U.S. Pat. Nos. 2,626,230 and 2,885,099 relate to different gravity feed leg configurations but do not overcome the basic problems of length of the leg required for high pressure differentials.
High density liquids are suggested by U.S. Pat. Nos. 2,704,704 and 3,009,588 to develop the desired pressure differential, but the liquids suggested, such as molten lead, mercury, tin, provide severe economic and environmental disadvantages.
Sealing liquid such as water, is suggested by U.S. Pat. No. 2,828,026 in a system employing a drum with rotating feeder buckets. The operating pressure of a retort is balanced by a liquid standpipe and is again restricted to use over small pressure differentials, due to the height requirements of the liquid standpipe.
U.S. Pat. No. 2,925,928 suggests feeding coarse solids through a fluidized bed of finely divided solids in a standpipe to balance the pressure difference between two zones of different pressure. However, use of this system over pressure differentials of only about 10 to 20 psi is practical.
U.S. Pat. No. 3,729,105 teaches a lockhopper which contains liquid, serving as a liquid seal, through which a higher density solid falls and is fed to a pressurized vessel by a feeder, such as a screw feeder. This system may be used with higher pressure differentials than prior systems, but has disadvantages of the solids carrying undesired liquids into the pressurized vessel, especially with small particle size solids, and permits the liquid to be carried into the pressurized vessel, such as a reactor, if there is a depressurization surge in the reactor. It is apparent that in many reaction systems entry of the liquid into the reactor may be ruinous.

Solids feeder having a solids-liquid separator


The invention relates to a method of establishing a voice call between a calling party's terminal (5), which is connected to a telephone network (4), and a called party's terminal (6), which is also connected to the telephone network (4), through an Internet Protocol (IP) network (1). To make the method as simple as possible, it is proposed to use conventional IP servers (2; 3) of IP service providers for providing access to the IP network (1). The IP network (1) includes at least one Voice-over-IP (VoIP) server (11), which controls the functions of telephony over the IP network (1). The VoIP server (11) receives the request for an IP call from the calling party, activates the still inactive terminal (6) of the called party over the telephone network (4), determines the IP addresses of the terminals (5, 6), and communicates the IP addresses to the respective other terminal (5; 6). The terminals (5, 6) then establish a voice call between them through the IP network (1).

The present invention relates to a method of activating an inactive terminal of a data network, which terminal is connected to a telephone network, for establishing a connection through the data network between a further terminal and the terminal to be activated. The invention also relates to a server of a data network, to an adapter unit connected between a terminal of a telephone network and the telephone network, to a telephone, and to a microcomputer, preferably a personal computer, comprising a modulator-demodulator (modem) or an ISDN adapter.
The present invention relates to the field of telephony over data networks, particularly to the field of telephony over Internet Protocol (IP) networks, so-called Internet telephony.
It is known in the art to use IP networks (e.g., the Internet or intranets) for telephony. Internet telephony, also referred to as "Voice over IP" (VoIP), is expected to find wide use, because it provides considerable cost savings over conventional telephone calls through the telephone network, particularly in the case of long-distance and international calls. For VoIP, both the calling party and the called party must have terminals with Internet access. To be able to make a call through an IP network, both terminals must be connected to the Internet. Connections between the terminals and the Internet are commonly established through the telephone network at the local call rate. The actual long distance between the calling party and the called party, which is very expensive in the case of a conventional voice call over the telephone network, is covered via the IP network, in which rates are generally very low.
There are various methods for carrying out VoIP. An essential difference between the methods lies in the type of terminals used. Frequently, use is made of multimedia-capable personal computers (PCs) on which suitable software for transmitting speech data over the IP network is installed. This permits telephony from PC to PC via an IP network. Using suitable compression techniques, the amount of data to be transmitted over the IP network can be reduced to about 8 to 12 kb/s. If sufficient bandwidths are available, speech quality is acceptable and corresponds to that in mobile radio networks.
In PC-to-PC telephony, however, the circle of users is greatly limited, since a large number of potential users of Internet telephony do not have a PC or a suitably equipped PC. Therefore, Internet telephony solutions are being offered in which an interface from a conventional telephone network to an IP network is implemented using a so-called gateway. This permits VoIP between a PC and a conventional telephone (analog or ISDN) or even between two telephones.
In Internet telephony via gateways, the calling party dials the number of a first gateway, which is located as close to the caller as possible. The connection to the gateway is established through the conventional telephone network. Next, the calling party dials the number of the desired party. The first gateway then establishes an IP connection through an IP network to a second gateway, which is closest to the called party. From the second gateway, a conventional telephone connection is then established to the called party.
In the prior art, providers of Internet telephony must maintain a gateway in as many local networks as possible so as to enable users of Internet telephony to access the IP networks nationwide at the lowest possible rate (the local rate). However, the installation and maintenance of the gateways is very expensive and nullifies most of the cost advantages offered by Internet telephony. This is one of the main reasons why Internet telephony has not yet become accepted.

Method of activating an inactive terminal of a data network, particularly of an IP network


A multi-domain liquid crystal display includes multiple first and second picture elements and multiple first and second auxiliary electrodes. The first and second picture elements have opposite polarities under the same frame of an inversion drive scheme, and each picture element has a reflective region and a transmissive region. The first auxiliary electrodes are connected to the first picture elements, and each of the first auxiliary electrodes is positioned next to at least one side of one second picture element. The second auxiliary electrodes are connected to the second picture elements, and each of the second auxiliary electrodes is positioned next to at least one side of one first picture element.

(a) Field of the Invention
The invention relates to a multi-domain liquid crystal display and, more particularly, to a multi-domain liquid crystal display having both transmissive regions and reflective regions.
(b) Description of the Related Art
Typically, the display contrast ratio and response speed offered by a vertically aligned (VA) mode liquid crystal display (LCD), which uses negative liquid crystal materials and vertical alignment films, are better than a twisted-nematic (TN) mode LCD, since liquid crystal molecules are aligned in a vertical direction when no voltage is applied. Also, it is known the viewing angle performance of a VA mode LCD is improved by setting the orientation directions of the liquid crystal molecules inside each picture element to a plurality of mutually different directions; that is, forming multiple distinct domains in the liquid crystal display.
FIG. 1A shows a schematic diagram illustrating a conventional design of a multi-domain vertically aligned liquid crystal display (MVA LCD). Referring to FIG. 1A, a top substrate 102 and a bottom substrate 104 are both provided with protrusions 106 having different inclined surfaces and covered by vertical alignment films 108. Hence, the liquid crystal molecules 112 near the inclined surfaces orientate vertically to the inclined surfaces to have different degrees of pre-tilt angles. In case the pre-tilt liquid crystal molecules exist, surrounding liquid crystal molecules 112 are tilted in the directions of the pre-tilt liquid crystal molecules 112 when a voltage is applied. Thus, multiple domains each having individual orientation direction of liquid crystal molecules 112 are formed. Besides, the domain-regulating structure for providing inclined surfaces includes, but is not limited to, the protrusions 106, and other structure such as a via structure 114 shown in FIG. 1B may also be used.
However, when one compares the optical path of light I1 and that of light I2 shown both in FIGS. 1A and 1B, it is clearly found the tilted liquid crystal molecules through which the light I2 passes under a field-off state may result in a non-zero phase difference (.nd.0) to cause light leakage. Accordingly, additional compensation films must be provided to eliminate the light leakage.
FIG. 2 shows a schematic diagram illustrating another conventional design of an MVA LCD. Referring to FIG. 2, the transparent electrode 204 on the substrate 202 is provided with slits 206. Because of the fringe fields produced at edges of transparent electrode 204 and at each slit 206, the liquid crystal molecules 208 are tilted toward the center of each slit 206 to result in a multi-domain liquid crystal (LC) cell. However, the strength of the fringe fields generated by the formation of the slits 206 is often insufficient, particularly when the widths and the intervals of the slits 206 are not optimized. Besides, since the azimuth in which the liquid crystal molecules tilt due to the fringe fields includes all directions of 360 degrees, a disclination region 210 often appears beyond the slits 206 or between two adjacent slits 206 to result in a reduced light transmittance.
Further, though the protrusion 106, via structure 114, or slit 206 may be provided to create multiple domains, the distribution of these structures in a picture element may reduce the active display area as well as the aperture ratio of the picture element.
Moreover, in a transmission type LCD device, a backlight is used to obtain a bright display independent of surrounding environments, and thus the panel brightness is often not sufficient when the device is exposed to direct sunlight. In comparison, in a reflection type LCD device, surrounding light is employed to effect a display, so that the backlight source can be omitted; however, the reflection type LCD device is largely deteriorated in visibility in a dark surrounding. Hence, there has been a strong demand for providing an optimal design of a multi-domain LCD device having both transmissive regions and reflective regions to achieve good visibility in any environment.

This patent is subject to a terminal disclaimer.


Provided is a turbine fuel pump for a vehicle. More particularly, provided is a turbine fuel pump for a vehicle that can improve efficiency of the fuel pump and solve pressure instability caused by collision of fuel by forming a separate independent channel in a lower casing, an impeller, and an upper casing where channels of fuel are formed at the time of suctioning fuel from the fuel tank and supplying fuel to an engine of an internal combustion engine.

In general, a fuel pump of a vehicle is mounted on the inside of a fuel tank of the vehicle and serves to suction fuel and pressure-feed the suctioned fuel to a fuel injection device mounted in an engine.
In addition, the fuel pump for the vehicle is classified into a mechanical fuel pump and an electrical fuel pump and a turbine fuel pump 10 which is a type of electrical fuel pump is primarily used in an engine using gasoline as fuel.
In the turbine fuel pump 10, a driving motor 20 is provided in a motor housing 60 of the fuel pump 10, an upper casing 30 and a lower casing 40 are provided on a lower end part of the motor housing 60 to be closely attached to each other, and an impeller 50 is interposed therebetween as shown in FIG. 1.
In addition, the impeller 50 is joined to a rotational shaft 21 of a driving motor 20, such that the impeller 50 is configured to rotate with the driving motor 20.
That is, as the impeller 50 rotates, a pressure difference is generated, and as a result, fuel is suctioned into the impeller 50 and while the pressure of fuel is increased by a rotation flow generated by continuous rotation of the impeller 50, fuel is discharged.
Therefore, fuel is introduced into a fuel suction port 41 of the lower casing 40 to flow to a check valve 70 formed in an upper part of the motor housing 60 along an inner part of the motor housing 60 through a fuel discharge port 31 of the upper casing 30 with the pressure thereof increased through the rotating impeller 50 and supplied to the fuel injection device mounted on the engine of the vehicle.
In this case, the impeller 50 is formed in a disk shape, a plurality of blades 51 are formed on an circumferential surface thereof in an outer direction of the circumferential surface, blade chambers 52 are formed among respective blades 51 to penetrate through both surfaces of the impeller 50 as shown in FIG. 2, such that fuel is introduced and discharged individually in an upper part and a lower part of the blade chamber 52 and fuel is introduced into the fuel suction port 41 of the lower casing 40 to generate the rotation flow in a space between a blade chamber 52 and a lower channel groove 42 formed in the lower casing 40 and an upper channel groove 32 formed in the upper casing 30 as shown in FIG. 3, and a circulation process in which fuel is again introduced into the neighboring blade chamber 52 to generate the rotation flow is repeated. Therefore, kinetic energy generated by the rotation of the impeller 50 is converted into pressure energy of fuel, and as a result, fuel is delivered to the fuel discharge port 31 of the upper casing 30.
In addition, in the impeller 50 in the related art, a circumference center guide 53 is formed at the center of the circumferential surface along the circumferential surface of the impeller 50 so as to efficiently generate the rotation flow formed in the space between the blade chamber 52 and the lower channel groove 42 and the rotation flow generated in the space between the impeller chamber 52 and the upper channel groove 32.
In this case, as shown in FIG. 4, the fuel that flows along the upper channel groove 32 of the upper casing 30 is discharged through the fuel discharge port 31. However, the fuel that flows along the lower channel groove 42 of the lower casing 40 should be discharged through the fuel discharge port 31 by passing through the blade chamber 52 of the impeller 50.
Therefore, the fuel that flows along the lower channel groove 42 hits the blade 51 of the impeller 50 and passes through the blade chamber 51 to interrupt the flow of the rotation flow, thereby causing loss of a fuel movement amount and further, serve as flow resistance of fuel to make the pressure of the fuel pump instable and deteriorate performance.
Further, with a current technological tendency in which components in the vehicle are gradually subjected to a light weight, a compact size, and high performance in order to satisfy user's various preferences globally, a study about high performance of even the fuel pump has been required.
In addition, performance of the fuel pump is determined according to a specification of the vehicle and high efficiency is required as a recent trend. Therefore, the turbine fuel pump for a vehicle in the related art is limitative in increasing a discharge amount of fuel under high pressure.


A slurry of coal particles is dewatered by agglomerating the coal particles using a hydrocarbon binder at an elevated temperature to obtain coal pellets which are then heat treated. Gases released by the pellets during heat treatment may be heat exchanged with the slurry or burned to produce heat for the heat treatment, steam for the heat treatment, or to provide mechanical energy for the agglomeration.

This invention relates to dewatering of coal slurries, and in particular to a process and plant for the production of hardened pellets from a coal slurry.
Coal may be classified according to its size. Particles larger than, say, 25 mm are generally referred to as "lumps". Between 25 mm and, say 150 microns the particles may be referred to as "grains", and below 150 microns as "fines". The actual dividing lines are not firmly fixed; for instance, that separating the grains from the fines may lie anywhere between 75 microns and 250 microns, though more usually it is taken at 100 or 150 microns.
This specification is mainly concerned with grains and fines, since it is that these are most usually found in coal slurries, such as those used for pipeline transport. Larger lumps are difficult to transport as a slurry as they require a large energy input to keep them in suspension; fines on the other hand lend themselves to such pipeline transport, but are not easy to dewater.
One technique which is suitable for dewatering fines is agglomeration using a binder. The resulting agglomerates can then be separated mechanically from water and any non-agglomerated matter by, for example, filtration or centrifuging. Depending on the method of fabrication, the agglomerates can be made into quite hard pellets, but "green" pellets, i.e. those which have not undergone some heat treatment or curing, are weak and may break up during handling. Curing of the pellets requires a heat input which adds to the cost of the processing; it can also lead to the production of noxious odors and fumes.
U.S. Pat. No. 1,589,023 relating to a process for cracking coal and oil has some pertinence to the invention.


A spatial light modulator includes a multiple quantum well (MQW) device. Unlike MQWs of the prior art, this MQW is made semi-insulating. As a result, individual picture elements can be defined entirely by the placement of electrodes in an array on a surface of the device. Them is no need to etch trenches for electrical isolation of the picture elements.

As the field of image processing continues to advance, there is an increasing demand for spatial light modulators (SLMS) that can impress a two-dimensional pattern on a beam of light at high speed and high resolution. Although liquid crystal SLMs have been known for many years, these devices are too slow for some modern applications. A faster alternative to the liquid crystal SLM is a solid state SLM in which a multiple quantum well (MQW) is included in the intrinsic region of a p-i-n diode structure. The use of structures of this kind for light modulation is described, for example, in U.S. Pat. No. 4,525,687, issued to D. S. Chemla et al. on Jun. 25, 1985, and in U.S. Pat. No. Re. No. 32,893, reissued to D. A. B. Miller on Mar. 21, 1989.
In order to achieve high resolution without incurring prohibitive manufacturing costs, it is desirable to fabricate these SLMs as monolithic devices. Because the p-i-n structure is semiconductive, it is necessary to include in the manufacturing process lithographic patterning and etching steps that isolate each picture element in a discrete mesa. Elimination of these steps would result in reduced manufacturing costs.

Spatial light modulator using quantum well material


A cart is provided for safely transporting and storing a single, large, vertically-oriented, cylindrically-shaped canister having a horizontally-oriented base. The vertical and horizontal orientations of the canister and its base, respectively, are constantly maintained throughout the transporting and storing of the canister. The cart includes a stable base. The stable base includes a bottom platform and four wheels operatively connected to the stable base and configured to support the weight of the canister. The stable base is configured to receive and support the horizontally-oriented base of the canister. The cart further includes two side rails extending upwardly from the stable base. A circumferential band is removably attached to the side rails and is configured to encircle and secure from movement the canister, within the cart. The band is at an elevation above the horizontally-oriented base of the canister.

Reusable liquid and gas canisters or cylinders 2, as shown in FIGS. 1A and 1B, are used to store cryogenic liquids or gasses for industrial use. These canisters or cylinders are filled with liquid and transported to an industrial site for use and storage. When the liquid is depleted, the canisters are then transported to a liquid supplier and refilled. These canisters or cylinders typically weigh from 600 to 900 pounds or more when full, and must be handled with care to ensure the safety of persons transporting and handling them.
One device for transporting large liquid cylinders is a liquid cylinder truck 4, as shown in FIGS. 1A and 1B. FIG. 1A illustrates the cylinder truck 4 in its upright, standing position, while FIG. 1B illustrates the cylinder truck 4 in its tilted position for movement of the liquid cylinder 2. The liquid cylinder truck 4 includes a lifting platform (not shown) which is positioned under the cylinder 2 by tilting the cylinder 2 onto an edge of its base 2A. A spring loaded hanger 6 is connected to the cylinder 2 at its handling ring or halo 8. An operator holds a handle 10 and rocks the cylinder truck 4 back on its wheels 12, as illustrated in FIG. 1B, to transport the cylinder 2. Rear casters 14 may be provided to prevent the cylinder 2 from rocking too far and tipping onto the operator. Maneuvering the cylinder 2, which can weigh in excess of 900 pounds, can be dangerous for operators. Any shifting of the cylinder 2 can trap and crush fingers, hands, arms, legs, or other body parts of the operator against the ground, walls, or other objects. Furthermore, the cylinder truck 4 is only supported by two wheels 12 during transport, and consequently may not be stable on inclined or difficult terrain. Finally, the spring loaded hanger 6 can become disengaged, causing the operator to lose control of the cylinder 2.
Accordingly, there exists a need for an apparatus and method for transporting, handling, and storing large liquid cylinders or canisters that provide increased operator safety.


A method and device for cleaning solid elements such as glass making moulds. The moulds are cleaned by first removing greases or organic materials and then cleaning by photo-ablation by a laser impact of at least a portion of the surface of the moulds. The two steps may be repeated.

1. Field of the Invention
This invention relates to a method of cleaning solid elements, such as moulds, and more especially the cleaning of glassmaking moulds.
2. Discussion of the Background
Although the invention concerns other industries, its explanation will be limited to the cleaning of glassmaking moulds. Glassmaking moulds, notably those used for the production of bottles or flasks, are of several types; they may be, for example, roughing moulds and finishing moulds. These moulds operate most commonly at very high production rates, that is to say they produce a large number of bottles or flasks very rapidly. During manufacture these moulds and, more particularly, the zones that come into contact with the glass, are treated with agents such as greases. Consequently, this type of mould becomes dirty very rapidly and therefore must be regularly cleaned to give finished products of good quality.
In glassworks operating at the usual high rates, the roughing moulds are cleaned approximately every two days and the finishing moulds approximately once a week.
The techniques commonly used for cleaning glassmaking moulds are of the mechanical type. Sandblasting or indeed polishing techniques, for example, may be used. It appears that these techniques are entirely satisfactory from the cleaning aspect, and enable the entire layer of dirt which becomes deposited during use to be removed.
In contrast, it has become apparent that these treatments are generally too severe. In fact, simultaneously with the removal of the dirt, this type of treatment damages the metal of which the mould is made. Such damage of the mould, which corresponds at each cleaning to an erosion of approximately 10 microns from the surface of the mould, has harmful consequences.
In fact, the size of the cavity or indentation, that is the place where the product is formed, is increased, which leads either to a greater consumption of glass for an equivalent product or a variation in the capacity of the article for a constant consumption of glass. The external dimensions of the articles are also modified and no longer meet the requirements. Furthermore, these deformations lead to problems of demoulding which generally result in defects or breakage of the finished products. Most commonly, the finished products have a surface state which degrades with the aging of the mould. These disadvantages lead to maintenance costs for repairing the moulds which are generally high and to premature replacement of these moulds.
The French Patent published under number 2 641 718 describes a cleaning method which enables different types of dirt on surfaces, for example metal surfaces, to be removed without wear or degradation of the metal. This is a technique of photo-ablation by laser impact. Tests have shown that the application of this method to the cleaning of glassmaking moulds enables the film of dirt to be effectively removed without degradation of the surface of the mould. On the other hand, the application of this method to the cleaning of moulds does possess disadvantages which make it unacceptable from an industrial aspect. In fact, the time necessary for performing the cleaning of a mould by this method is too long and cannot be reconciled with the production rates necessary for cleaning glassmaking moulds.
The moulds have, in addition, geometries that are frequently complicated, which make them difficult to clean by a laser beam which cannot reach all the corners and, notably, the grooves and fins present on the outer surface of the mould. The regions of the moulds that enable the different parts of which the moulds are made to be fitted and hooked together are also very difficult of access by a laser beam. The cleaning of these regions by such a technique would necessitate difficult handling operations which by their nature are relatively slow.

Method and device for cleaning solid elements


A credit card imprinter having a number of rotatable type faces to imprint the amount of purchase on a credit card receipt. The type wheels are coaxially arranged and rotatably supported adjacent and in contact with the receipt to be imprinted. The imprinter is provided with a mechanism for positioning the type wheels which includes a member which translates along the type wheels to successively set same to the desired position, thereby allowing all of the type wheels to be positioned with a single mechanism. A roller is then used to imprint the type on the receipt and the type wheels are reset to the starting position by a reset mechanism.

Imprinters typically used in recording credit card sales transactions may be broadly classified as the type having variable data imprinting means and the type capable of only recording preset data contained on the imprinter and the credit card. An example of a credit card imprinter of the type which merely records the information on the credit card and the information on the dealer's plate affixed to the imprinter is shown in U.S. Pat. No. 3,810,424 (Barbour). The printer has a generally horizontal upper deck which supports the purchaser's credit card and a dealer plate affixed to the deck containing the dealer's name, address and identification code. The multi-ply credit card receipt is placed on the deck above the credit card and dealer plate and then a roller is translated across the deck imprinting the raised indicia on the credit card and dealer plate onto the multi-ply receipt. The dollar amount of the sale and other information, such as the date and cardholder's signature is then written on the receipt by hand.
A current trend in the industry is to use optical reading equipment to process the credit card receipts. Optical reading equipment cannot reliably read handwritten dollar amount due to the wide variation in handwriting styles. It is, therefore, necessary to imprint the dollar amount on the receipt with a type wheel if the receipt is to be automatically read by optical equipment. A number of credit card imprinters having dollar amount wheels which can be set by the user are presently available. An example of such a device is shown in U.S. Pat. No. 3,739,716 (Barbour) which employs a number of toothed racks, each of which engage a gear formed on a rotating type wheel. The user positions the handle portion affixed to the rack to set the dollar amount of the transaction. Each of the type wheels act independently of one another.
A problem with conventional credit card imprinters capable of printing variable data is that the devices tend to be bulky and occupy a great deal of counter space. Credit card imprinters are typically placed on a counter adjacent a cash register and the counter space is often very limited. In addition, imprinters having variable dollar amount type wheels are frequently expensive, as these mechanisms are relatively complex.

Variable data imprinter for credit cards and the like


Leakage current control devices include a circuit having one or more functions in a data path where the functions are executed in a sequence. Each of the functions has power reduction logic to energize each respective function. A leakage control circuit interacts with the power reduction logic, so that the functions are energized or deenergized in a control sequence such that the functions where the data is resident are energized and at least one of the other functions is not energized.

1. Field of the Invention
The present invention relates to microelectronic circuits, and more particularly to a structure and method to control leakage current in subunit microelectronic circuits.
2. Description of the Related Art
Power consumption due to leakage current is increasing rapidly in modern very large scale integration (VLSI) design and is becoming a significant problem in not only meeting the thermal envelope in high performance designs, but also meeting power dissipation constraints in low-power portable devices.
Conventional designs require a control signal that activates or deactivates leakage reduction logic. This is typically performed at chip level; for example, a processor goes into sleep mode. One long-standing problem includes leakage at the subunit level, which is typically not controlled (in both hardware and for predictive method techniques), for example, in microprocessors and memories, such as at pipeline stages, or portions of pipeline stages.
Therefore, a need exists for a system and method for controlling leakage at the subunit level in electronic circuits.

Method and structure for short range leakage control in pipelined circuits

International Business Machines Corporation


A reactor vessel for performing a steam reforming reaction having a vessel inlet for natural gas and steam; a vessel inlet for a hot gaseous medium; a vessel outlet for the steam reforming product; and a reactor space which is a bed of steam reforming catalyst, which reactor space inlet is fluidly connected to the inlet for natural gas and steam and at its outlet end fluidly connected with the outlet for the gaseous product; wherein inside the catalyst bed a passageway is provided fluidly connected to the vessel inlet for the hot gaseous medium for passage of hot gaseous mixture counter currently to the flow of reactants in the catalyst bed.

EP-A-168892 describes an endothermic steam reforming reaction, which is carried out in a fixed bed situated in at least one pipe in which a temperature of between 800 and 950° C. is maintained by routing at least part of the hot product gas from a partial oxidation reaction along the pipe(s). According to this publication the combined partial oxidation and endothermic production of synthesis gas result in a better yield of synthesis gas, an increased H2/CO ratio, a lower usage of oxygen per m3 of synthesis gas product obtained and a lower capital cost of the plant for the production of CO and H2-containing gas mixtures (as compared to partial oxidation).
A reactor and process for performing a steam reforming reaction is described in DE-A-3345088. This publication describes a reactor vessel for performing a steam reforming reaction starting from a natural gas feedstock. The vessel consisted of a tube sheet from which a plurality of tubes filled with a suitable catalyst extended into the vessel. The required heat of reaction is provided by passing the hot effluent of a partial oxidation reaction of natural gas at the exterior of the reactor tubes in the vessel. Such steam reformer reactors are also referred to as so-called convective steam reformer reactors.
A disadvantage of the known reactor vessel design is that fouling may occur at the exterior surface of the reactor tubes. This fouling will result in a less favorable heat exchange between hot gas and the catalyst bed and in time result in a less efficient operation. Short run times will result due to frequent shutdowns in order to remove the deposits. Fouling is especially a problem when the hot effluent of a partial oxidation reaction is used. This effluent is especially suited for providing the required heat due to its high temperatures. However, the soot present in this effluent will cause the above fouling problems.
EP-A-983964 describes a convective steam reforming reactor vessel, wherein the vessel is provided with a plurality of reactor tubes containing a catalyst bed. Around the reactor tubes an annular sleeve is provided to transport a hot effluent of an auto thermal reformer (ATR). By indirect heat exchange between this hot effluent and the reactants passing through the catalyst bed the steam reforming reaction can take place.
WO-A-0137982 discloses a reformer tube of the so-called double-tube configuration of a steam reformer reactor. The double-tube configuration consists of a reactor tube provided with a catalyst bed in which bed an inner return tube is provided for passage of the reactants being discharged from said catalyst bed. The double-tube configuration is described in more detail in U.S. Pat. No. 4,690,690 according to WO-A-0137982. The inner tube as disclosed in WO-A-0137982 has a non-circular cross-section.
WO-A-8801983 discloses a convective steam reforming reactor vessel wherein the hot gas, which is used to heat the reactor tubes, is obtained by burning heating gas in a lower part of the vessel.
It would be useful to provide a reactor design for a convective steam reformer, which is suitable to make use of a hot gaseous medium, which may cause fouling, as for example the effluent of a partial oxidation, as the heating medium. It would also be useful to provide a process for the preparation of a mixture of hydrogen and carbon monoxide by a process involving the combination of partial oxidation and steam reforming wherein the problems regarding fouling as described above are minimized.

Reactor vessel for performing a steam reforming reaction and a process to prepare synthesis gas


An attachment for cutting machine tools, such as band saws, spindle-shapers, sanders and the like, controlling the feed path of the workpiece to the cutting tool to form desired workpiece contours, such as circles, arcs and the like, has a grooved track bar easily locked on and removed from the machine bed or table carrying a slide in the groove which has a workpiece centering pivot pin projecting therefrom. A workpiece is either directly pivoted on the pin or secured to a templet pivoted on the pin and is rotated about its pivot support against the cutting tool. The slide may be locked in the groove at a selected distance from the tool, may be pushed against a stop at a selected position in the groove or may be shifted by a cam to control the feed path of the workpiece for forming desired contours. Circles of selected diameters, elipses of selected minor and major radii, heart shapes, four leaf clover shapes and the like are easily developed.

Standard work tables for cutting tools such as band saws, spindle shapers, sanders and the like are conventionally only provided with mountings for workpiece guide fences and do not accommodate adjustable workpiece pivots controlling arcuate feed paths to the cutting tool. Drilling of pivot pin holes in such work tables or beds can, at best, only accommodate relatively short cutting radii.

Cutting guide attachment for power tools


A semiconductor device includes a semiconductor layer having a main surface (100a), a first region (101) of a first conductivity type, a second region (102) of a second conductivity type, and a third region (103) of the second conductivity type, the first region (101) and the second region (102) having a first boundary (101a) formed therebetween, the first boundary (101a) being perpendicular to the main surface (100a), the third region (103) being formed in the first region (101) in spaced apart relation to the second region (102), the third region (103) having a depth less than the depth of the first boundary (101a) from the main surface (100a); and a control electrode (201) insulated from and overlying the main surface (100a) and extending from the first boundary (101a) to a second boundary (101b) formed between the first region (101) and the third region (103). The semiconductor device improves a tradeoff between breakdown voltage and on-resistance. A method of manufacturing the semiconductor device is also provided.

1. Field of the Invention
The present invention relates to discrete or integrated circuit semiconductor devices and a method of manufacturing the same.
2. Description of the Background Art
FIG. 20 shows a cross section of a background art output transistor. The output transistor of FIG. 20 comprises an n+ semiconductor substrate 1b, an nxe2x88x92 epitaxial layer 2b, p-type diffusion regions 191, n+ diffusion regions 193 formed in the respective surfaces of the p-type diffusion regions 191, a control electrode 291, an insulation film 3b surrounding the control electrode 291, a source electrode 293 in contact with the insulation film 3b, the p-type diffusion regions 191 and the n+ diffusion regions 193, and a drain electrode 292 in contact with the bottom surface of the semiconductor substrate 1b.
In the structure shown in FIG. 20, the p-type diffusion regions 191 and the n+ diffusion regions 193 are formed using the insulation film 3b as a mask. The difference in lateral diffusion length between the p-type diffusion regions 191 and the n+ diffusion regions 193 defines MOS channels CH.
The structure of FIG. 20 is known as a DMOS (Double diffused MOS) transistor. The DMOS transistor which uses the nxe2x88x92 epitaxial layer 2b as an offset drain has a reduced gate length independently of photolithographic precision and can ensure the uniformity of the gate length. Therefore, DMOS transistors are most commonly used as high breakdown voltage devices which require low on-resistance.
A significant aim of the DMOS transistors is to improve a tradeoff between breakdown voltage and on-resistance. To achieve this aim, generally two approaches to such an improvement have been made.
The first approach is to increase the mask alignment precision of a stepper to reduce the size of devices, thereby improving the tradeoff between breakdown voltage and on-resistance.
The second approach is to shorten a channel length by making the p-type diffusion regions 191 and the n+ diffusion regions 193 shallower to reduce a JFET resistance between the pair of p-type diffusion regions 191, thereby improving the tradeoff between breakdown voltage and on-resistance.
However, the first approach provides an improvement effect which substantially reaches a point of saturation since the precision of mask alignment at the current level may be considered equivalent to the processing precision of an entire process. Therefore, the first approach is not expected to provide a further considerable improvement in the tradeoff between breakdown voltage and on-resistance.
It is hence considered to apply the second approach to the first approach. Unfortunately, the second approach can reduce the channel length and the JFET resistance, but is not capable of suppressing the increase in curvature of a diffusion corner. The increase in curvature of a diffusion corner decreases the breakdown voltage. Thus, the application of the second approach to the first approach encounters limitation of the improvement in the tradeoff between breakdown voltage and on-resistance.
According to a first aspect of the present invention, a semiconductor device comprises: a semiconductor layer including a main surface, a first region of a first conductivity type, a second region of a second conductivity type, and a third region of the second conductivity type, the first region and the second region having a first boundary formed therebetween, the first boundary being perpendicular to the main surface, the third region being formed in the first region in spaced apart relation to the second region, the third region having a depth less than the depth of the first boundary from the main surface; and a control electrode insulated from and overlying the main surface and extending from the first boundary to a second boundary formed between the first region and the third region.
Preferably, according to a second aspect of the present invention, in the semiconductor device of the first aspect, the first region has an impurity concentration decreasing with increase in distance from the main surface of the semiconductor layer.
Preferably, according to a third aspect of the present invention, in the semiconductor device of the first aspect, the main surface has a polygonal plan configuration, and the first region is disposed at a vertex of the polygonal plan configuration.
According to a fourth aspect of the present invention, a method of manufacturing a semiconductor device comprises the steps of: (a) implanting a first impurity of a first conductivity type and a second impurity of a second conductivity type into a first region formed in a main surface of a semiconductor layer and a second region adjacent to the first region, respectively; (b) heat-treating a resultant structure provided in the step (a) to diffuse the first and second impurities; and (c) forming a third region of the second conductivity type in the main surface in the first region in spaced apart relation to the second region, and forming a control electrode insulated from and overlying the main surface, the control electrode extending from a first boundary formed between the first and second regions to a second boundary formed between the first and third regions.
Preferably, according to a fifth aspect of the present invention, in the method of the fourth aspect, the step (a) comprises the steps of: (a-1) covering at least the first and second regions in the main surface of the semiconductor layer with an oxide film; (a-2) covering part of the oxide film which overlies at least one of the first and second regions with a mask; (a-3) implanting one of the first and second impurities into the other of the first and second regions, the step (a-3) being performed after the step (a-2); (a-4) oxidizing part of the oxide film which is exposed over the other of the first and second regions to increase the thickness of the part of the oxide film, the step (a-4) being performed after the step (a-3); (a-5) removing the mask, the step (a-5) being performed after the step (a-4); and (a-6) implanting the other of the first and second impurities into the one of the first and second regions, the step (a-6) being performed after the step (a-5). The method further comprises the step of (d) removing the oxide film, the step (d) being performed prior to the step (c).
In accordance with the first aspect of the present invention, the first boundary between the first and second regions is perpendicular to the main surface to suppress the decrease in breakdown voltage. Additionally, the second region of the second conductivity type may greatly reduce on-resistance. Therefore, the present invention improves a tradeoff between breakdown voltage and on-resistance.
In accordance with the second aspect of the present invention, if a diffusion corner having a great curvature is developed at the bottom of the first region, the low concentration of the first impurity in the first region may suppress the decrease in the breakdown voltage.
In accordance with the third aspect of the present invention, the boundary between the first and second region contains at least the first boundary. This accordingly alleviates electric field concentration to render the semiconductor device less susceptible to breakdown.
In accordance with the fourth aspect of the present invention, the first boundary perpendicular to the main surface of the semiconductor layer is formed between the first and second regions. Additionally, the concentrations of the first and second impurities in the first and second regions decrease with the increase in distance from the main surface of the semiconductor layer. Therefore, if a diffusion corner having a great curvature is developed at the bottom of the first region, the semiconductor device in which the decrease in breakdown voltage is suppressed is achieved.
In accordance with the fifth aspect of the present invention, a bird""s beak is formed additionally in the step (a-4). A region immediately under the bird""s beak contains few first and second impurities. The presence of a gap containing few impurities prevents the position of the first boundary between the first and second regions from being shifted out of the region immediately under the bird""s beak, to provide the first boundary which is substantially stable and planar.
It is therefore an object of the present invention to provide a novel semiconductor device which improves a tradeoff between breakdown voltage and on-resistance, and a method of manufacturing the same.
These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

Semiconductor device and method of manufacturing same


A control system for controlling the illumination intensity of a gas discharge lamp to provide only necessary illumination and thus conserve power consumption. The control system has a daylight harvester which produces a control signal related to the available light within a given area. The control signal is conducted to a voltage controlled oscillator which, in turn conducts an oscillating signal to a frequency controlled ballast transformer that effectively drives the gas discharge lamp controlling the illumination intensity and energy consumption. The control system alternatively comprises a remote signal receiver for use alone or in addition to the daylight harvester. The control system with a remote signal receiver is controllable using a remote signal generator such as laser pointer. The remote signal receiver allows the user to control the illumination intensity of a gas discharge lamp from the area being illuminated.

Gas discharge lamps are widely used to illuminate relatively large areas and are actually preferred over incandescent lights in many situations for various reasons. Gas discharge lamps provide the benefit of providing equal or better illumination intensity using relatively less energy than the alternative incandescent lights. These energy efficient lamps are highly beneficial in geographic locations having a reduced power supply and in areas where cost benefits are realized by reducing energy consumption.
Although gas discharge lamps are generally more energy efficient than incandescent lamps, in large scale uses the lamps still consume significant amounts of power. Additionally, in many cases the illumination intensity generated by the lamps is actually more than necessary for a given situation. For example, in a large warehouse environments having skylights and other windows, natural daylight may actually provide most of the necessary illumination such that the gas discharge lamps actually produce supplemental and possibly unnecessary or excess light. Of course, on cloudy days and at night the gas discharge lamps provide the majority if not all the illumination required within the warehouse environment. During those times that the lamps are producing unnecessary light, the lamps are also consuming unnecessary power. Ideally, the lamps could be controlled to deliver sufficient illumination, depending on the availability of natural light, while consuming minimal power.
In many cases, the consumption of energy by the gas discharge lamps is directly related to the illumination intensity level produced by the lamps. During times when the lamps produce a relatively bright illumination intensity, a relatively higher level of the energy is typically consumed by the lamp.
Setting or controlling the circuit to deliver the proper amount of power to the lamp under variable conditions has typically required the use of a manual-type control mechanism. Such a manual control mechanism may be either a slide switch or a knob. Each of these mechanisms allow for the variable control of the illumination intensity but unfortunately also require that an operator physically manipulate the devices in order to vary the illumination intensity. This type of control is unsatisfactory in conditions where the light entering through the windows is constantly varying since the operator must continuously take the time to adjust the illumination intensity in accordance with the varying light conditions. Hence on intermittently cloudy days or at dusk the operator is continuously interrupted to adjust the illumination intensity.
Moreover, implementing a manual-type control switch introduces the possibility that the person operating the switch may incorrectly determine whether the lamp is generating the proper or optimal illumination intensity for a given situation. Manually adjusted control systems are also difficult to set since many lamps may need to be adjusted to various independent levels based on the location of the windows in the building. For instance, the lamps located far from windows or skylights most likely should be adjusted to provide more illumination than those lamps located near a window or skylight. Unfortunately, the typical control switch controls many of these lamps from one location so that the operator does not have to walk to many different locations to adjust the lights. However, this location may be relatively far from some of the lamps which decreases a person's ability to accurately detect whether the illumination intensity produced by each particular lamp is satisfactory, let alone optimal. Indeed, the operator can only guess the proper illumination intensity for each of the different zones illuminated by the various lamps.
In order to overcome these drawbacks, gas discharge lamps are generally operated at higher-than-necessary intensity levels based on worst-case scenarios. For example, on intermittent cloudy days, the lamps are generally set to provide sufficient illumination based on times when the cloud cover blocks most natural light. The result is that more illumination than necessary is generated during periods of time when the clouds have dissipated which results in unnecessary energy consumption.
It is with respect to these considerations and others that the present invention has been made.

Light sensing dimming control system for gas discharge lamps


A closure for a package that is adapted for mounting to a surface of the package includes a mounting flange having substantially planar upper and lower surfaces that define a thickness and define a flange plane. A spout extends from the upper surface of the flange and has an inner wall defining a dispensing opening. A membrane has a central portion and a circumferential edge region and is formed in the spout so as to extend to the inner wall to define a spout seal. The membrane is severable from the spout at the edge region. The edge region is selectively thinned and has a pair of first thickness regions and a pair of second thickness regions interposed between the first thickness regions. The second thickness regions have a thickness that is greater than a thickness of the first thickness regions.

Consumers have come to widely recognize and accept molded spouts as dispensing ports in packaging. One example, is the common gable top carton which is formed from a composite of paperboard and polymeric materials for the storage of, for example, liquid food products such as juice and milk. In an effort to provide maximum resealability of such packages, the industry has gone to using molded spouts mounted to the packages. These spouts can include threaded or snap-type, e.g., flip-cap, closures to provide maximum resealability of the package. These closures reduce the amount of degradation, i.e., spoilage, of the food product by reducing the exposure of the container contents to oxygen and airborne contaminants.
Known spout arrangements can also be used to provide tamper evidence or tamper indication as to whether the container has been opened, and the contents tampered with or altered in any way. In one known arrangement, a membrane is formed within the spout to seal the container contents from the environs. In order to access the container contents, the membrane must be removed from the spout. In one commonly used arrangement, a pull ring is formed as part of the membrane to facilitate removing the membrane from the spout.
While this arrangement has become accepted by the consuming public and has come into wide spread use in the packaging industry, there are a number of drawbacks. First, the membrane must be formed so that it is readily removed with a limited, predetermined amount of force required to pull the pull ring to remove the membrane. That is, the membrane must be sufficiently thin so that it can be readily severed and pulled from the spout. On the other hand, the membrane must have sufficient strength, generally correlative to thickness, so that it does not fracture or tear during, for example, mounting the closure to the package material or transport or the filled package, prior to initial use of the package.
Additionally, known spout-type packaging generally includes a tubular spout portion that extends upwardly from a flange that is mounted to the package. The membrane is formed intermediate the upper and lower ends of the spout, that is, of the flange and below the top end of the spout. In such an arrangement, the region between the membrane and the bottom of the spout, about coplanar with the flange, creates a pocket and thus an opportunity for bacterial growth, in that this pocket below the membrane can be difficult to sterilize.
Accordingly, there continues to be a need for closure spout barrier membrane that enhances the ability to pasteurize or sterilize the product, to maintain the necessary hygienic standards. Desirably, such a membrane maintains its integrity during the process of mounting the spout to the package, and is readily removable from the spout for easy access to the container contents.

Closure with flush-formed barrier membrane having selectively thinned edge regions


A method for forming a reflective digitally tunable laser using selective area epitaxy is disclosed. The laser comprises passive waveguides and a plurality of optical amplifiers. The waveguides and optical amplifiers are formed by depositing multiple quantum wells having a suitable bandgap. According to the method, the multiple quantum wells forming both the passive waveguides and the optical amplifiers are deposited simultaneously using a dielectric mask. The mask comprises dual, rectangularly-shaped strips of dielectric material, spaced to form a gap. The multiple quantum wells grown in the gap are suitable for use as optical amplifiers, and those grown outside of the gap are suitable for use as passive waveguides.

Photonic integrated circuits are typically comprised of a plurality of photonic devices, located on a semiconductor substrate, that are in optical communication with one another. Most methods for creating photonic integrated circuits involve forming one photonic device at a time. This is due to an inability to regionally vary the bandgap of the quantum well (QW) material being deposited in a given epitaxial growth.
In the methods noted above, the epitaxial layers required to form a first type of photonic device, such as a laser, are grown over the whole substrate. The temperature, pressure and source materials used for the growth are selected so that the quantum well (QW) material that is deposited has the requisite characteristics, i.e., band gap, to function as the desired device. The layers are then masked at the region where the first photonic device is desired. Subsequently, the layers in unprotected regions are etched away where other devices, such as modulators or waveguides, are desired. After etching, layers corresponding to a second type of photonic device are grown on the substrate in the etched regions. Growth conditions are adjusted for the second growth so that the QW material exhibits the appropriate band gap. If a third type of photonic device is desired, the layers are again masked and etched, conditions are adjusted and a third series of epitaxial layers are grown in the etched region.
Methods that utilize successive growths as described above may collectively be referred to as "etch and regrow" methods. Devices grown from the etch and regrow method frequently exhibit poor optical interface quality, which can result in internal reflections and coupling losses.
Selective area epitaxy (SAE) is an epitaxial growth method that minimizes the poor optical interface problems associated with the etch and regrow method. Using SAE, the bandgap of QW material can be varied in the same plane with a single growth. Thus, layers defining various photonic devices can be grown simultaneously. See Joyner et al., "Extremely Large Band Gap Shifts for MQW Structures by Selective Epitaxy on SiO.sub.2 Masked Substrates," IEEE Phot. Tech. Lett., Vol. 4, No. 9 (September 1992) at 1006-09 and Caneau et al., "Selective Organometallic Vapor Phase Epitaxy of Ga and In Compounds: A Comparison of TMIn and TEGa versus TMIn and TMGa," J. Crystal Growth, Vol. 132 (1993) at 364-70.
In the SAE method, dielectric masks, such as SiO.sub.x or SiN.sub.x, are deposited on a substrate. Such masks typically comprise two strips of dielectric material, spaced to form a gap. Source material for forming the epitaxial layers, such as indium (In), gallium (Ga), arsenic (As), and phosphorus (P), is typically delivered via metalorganic vapor phase epitaxial (MOVPE) methods.
Source material arriving from the vapor phase will grow epitaxially in regions where the mask is open, i.e, the substrate is uncovered. Source material landing on the mask itself will not readily nucleate. Given the proper temperature and mask width, most of the source material that lands on the mask reenters the vapor phase and diffuses, due to the local concentration gradient, to find an unmasked region.
Compared to a completely unmasked substrate, the QW growth that occurs in the gap for both InGaAs and InGaAsP epilayers will be thicker, and richer in indium. This effect is due to the relative diffusion coefficients of In and Ga under typical MOVPE growth conditions. As the QW layers thicken, changes occur in the quantum confined Stark effect resulting in longer wavelength (lower energy band gap) QW material. Increasing indium content also results in longer wavelength QW material. Thus, from both the quantum-size effect and change in alloy composition, the QWs in the gap are shifted to lower energy band gaps than regions far from the mask. By varying the ratio of the mask width to the gap (width), the composition, and hence the bandgap, of QW material can be varied.

Method for a reflective digitally tunable laser


A load-dispersing apparatus, configured to be placed against a torso front, includes a symmetric body having a breastplate, opposed legs extending downwardly from the breastplate, and opposed arms extending upwardly from the breastplate. The breastplate and the arms are rigid, and the legs are flexible.

Safety restraints, such as three-point seat belts, five-point harnesses, lap belts, and other restraining devices, are used frequently in motor vehicles to prevent movement of a person's body away from the vehicle. When in motion, a motor vehicle and all articles in and on the motor vehicle have momentum, the product of the article's mass and its velocity. Momentum carries an article in the same direction and with the same speed unless the article is acted upon by an outside force.
During an impact, an external object such as a car, railing, tree, etc. slows or stops the movement of the vehicle, thus reducing or eliminating its momentum. However, the object acts only on the vehicle; the momentum of articles within the vehicle is unaffected, and those articles tend to continue in the same direction and with the same speed just after the impact.
This discrepancy in momentum creates secondary impacts: a coffee cup may strike the window, a book may hit the back seat, or sadly, in some cases, a person may be thrown about within or outside of the vehicle. Safety restraints are used to reduce the effects of this momentum discrepancy. Safety restraints hold a person's body against the car seat and attempt to prevent them from moving out of or sideways from the car seat.
Safety restraints have phenomenally lowered fatality rates associated with motor vehicle accidents. Nevertheless, safety improvements continue to be made. Safety belts were provided with automatic pretensioners and locking retractors. Seat belt warning lights and bells were incorporated into cars. Air bags were developed. In short, a great deal of work has been done to ensure that passengers are protected in the event of an impact.
Unfortunately, while safety restraints prevent injuries, they can cause some as well. To reduce the momentum of a person's body, a seat belt exerts a huge amount of pressure against the body. It is not uncommon for a person to sustain a broken rib in an impact, wherein the rib is broken by the interaction of the body against the belt. In other situations, a person may be badly bruised, or their internal organs may be damaged by the pressure exerted by the seat belt. Some individuals, such as the elderly or those with osteoporosis, are especially at risk of injury from the seat belt.
Of course, it is preferable that all individuals use a safety restraint during an impact rather than go without; injuries from safety restraints are statistically less frequent and less severe than those due to an unprotected crash. However, a way to reduce the damage caused by safety restraints, or to prevent the injuries from them, is needed.

Safety restraint load dispersal brace apparatus


In a legged mobile robot, a pivoting motion of a foot (22) relative to a leg is controlled such that, from an intermediate time point in a period of departure of a leg from a floor to a starting time point of a period of landing of the leg on the floor, an angle (θ) of inclination of the foot (22) of the leg relative to the floor surface gradually approaches zero. This eases impact to the foot of the leg at the time of landing on the floor and prevents a slip or spin of the sole, thereby enabling stable walking or running.

Hitherto, there has been proposed a technique for easing a landing impact applied to a legged mobile robot when, for example, the robot moves up or down a staircase, and for stabilizing a motion thereof (refer to, for example, Japanese Patent Laid-Open Publication No. H5-318342).
However, when the robot runs by repeating a floating period during which all legs are apart from a floor surface and a landing period during which any portion of soles at the distal ends of a plurality of legs is in contact with a floor surface, the robot is subject to an especially high impact at the time of landing. Furthermore, because of, for example, an excessive moving velocity of the robot or angular velocity about a yaw axis in the floating period, there is a danger of the robot slipping or spinning at soles thereof when landing.
Accordingly, an object of the present invention is to provide a legged mobile robot capable of easing impacts when legs land and avoiding slippages or spins at soles of the legs so as to ensure stable walking or running, and a control program for the same.


Hydrogen Plasma surface passivation of III-V Semiconductors is critically dependent on exposure time and pressure because of competition between plasma passivation and damage. Proper control of pressure according to the invention yields reproducible and stable passivation. Improved passivation is obtained using high pressure hydrogen plasmas, i.e. above 1 Torr.

The well-known deficiencies in the surface properties of GaAs have stimulated many attempts to passivate the surface, reduce the surface state density, and unpin the surface Fermi level. There are many reasons why it is desirable to reduce the surface state density of III-V compound semiconductors and GaAs in particular. A reduction in surface state density would lead to improved field effect transistor (FETs) by lowering surface-related leakage currents and by increasing the Schottky barrier height. This would allow the fabrication of digital logic circuits with increased noise margins and relaxed requirements on threshold voltage uniformities of the component FETs. In addition, unpinning the surface Fermi level would allow advances in metal-insulator-semiconductor (MIS) capacitor and MISFET technology. For photonic devices, it is important for enhancing power output to reduce the surface recombination velocity and increase carrier lifetime. Passivation may be carried out prior to processing as a cleaning step, or after processing to remove process-induced damage.
A variety of wet chemical and photochemical treatments have been used to passivate GaAs but controversy remains as to their effectiveness in unpinning the Fermi level. Nonetheless, it is clear that photoluminesence (PL) yield is enhanced by using these surface treatments. In fact, passivation is operationally defined in terms of this enhancement in quantum yield. Although large increases in PL yield have been observed, the enhancements tend to be short-lived. We are aware of only one case where the enhancement persisted for more than a few hours (See H. H. Lee, R. J. Racicot, and S. H. Lee, Appl. Phys. Lett. 54,724 (1989). Occasionally, realtime PL monitoring has been used to monitor the effectiveness and kinetics of these wet chemical treatments.
To improve process control and management of environmental hazards, it is desirable to replace wet chemical processing with dry processing. In particular, plasma methods are effective for not only etching but also deposition, cleaning, and passivation. Recently, H.sub.2 plasmas operated at low pressure have been used to clean GaAs of residual As and As.sub.2 O.sub.3. Similar plasma treatments have also been reported for InP surface cleaning. A variety of reactor configurations have been employed: electron cyclrotron resonance (ecr) microwave, multi-polar, and rf diode. However, in these reports choice of optimal exposure times, which have ranged from 5 s to 30 min, and operating pressures, which have ranged from 10.sup.-4 to 10.sup.-2 Torr, is not discussed. Similarly, the consequences of reactor geometry or excitation mode choice have not been addressed. In one case the properties of Schottky diodes made on hydrogen plasma treated n-GaAs surfaces was studied as a function of the treatment temperature. The conclusion was that plasma passivation is ineffective for temperatures below 200.degree. C. (See A. Paccagnella, Appl. Phys. Lett. Vol. 55, No. 3, Jul. 17, 1989, pages 259-261). A similar conclusion has been made for hydrogen plasma treatment of InP surfaces. However, as we describe here, such conclusions depend on other plasma parameters. It is the recognition of the role of those parameters that leads to the inventive process.
Real-time monitoring of PL from GaAs during hydrogen plasma passivation clearly provides the means to investigate the effects of processing conditions such as exposure time, pressure, and temperature. (See U.S. patent application Ser. No. 07/402,030 filed Sep. 1, 1989). In addition, the kinetics of plasma-surface reactions can be monitored by measuring real-time changes in PL yield. In general, PL yield is sensitive to changes in surface recombination velocity (S) and band bending. Clearly, PL yield increases as S decreases. In addition, if the bands are bent and a space-charge field exists near the surface, separation of electrons and holes can lead to a reduction in radiative recombination efficiency. Thus, a reduction in band bending can increase PL yield. However, if S is reduced substantially, PL yield can increase despite an increase in band-bending. In n-GaAs, for example, passivation treatments tend to remove excess As from the surface and thereby reduce the As antisite defect density that pins the Fermi level near mid-gap. The Fermi level shifts to lower energy because the density of Ga antisite defects remains constant or even increases. Thus, the band bending increases. Ordinarily this would cause a decrease in PL yield as carriers are separated by the space-charge field. However, reduction of the near-mid-gap As antisite defect density decreases the non-radiative recombination rate causing an increase in PL yield.


A thin film magnetic head, and process for making the same, features a thin film magnetic transducer formed from multiple layers of film and having a magnetic yoke interacting with an electrical coil. The yoke has multiple magnetic flux circuits, deposited on multiple layers of film, encircling the center of the transducer and connected together by proximal and distal vias. A coil has multiple turns intertwined with the yoke, passing between the distal and proximal vias so that the distal vias are exterior to the coil and the proximal vias are interior to the coil, to provide at least four magnetic flux interactions between the coil and the yoke. In preferred embodiments at least one layer of the film is deposited with at least two pole pieces having different easy axis orientations. In other preferred embodiments at least one distal via is configured as an elongated "flux strap" for conducting magnetic flux along the length of the via in a direction oblique to the easy axis of either pole piece coupled together by the magnetic flux strap.

This invention relates to thin film magnetic transducers, particularly magnetic read/write heads.
Referring to FIG. 1, a typical thin film magnetic head 10 for writing information on or reading information from a recording medium 12, such as a magnetic disk, resembles a horseshoe-shaped yoke 14 of ferromagnetic material (such as nickel-iron) around which a coil 16 is wrapped. Yoke 14 includes a pair of pole pieces 18 the tips of which are located closely adjacent to medium 12.
Information is written on medium 12 by passing electrical current through coil 16 to induce a corresponding magnetic flux in yoke 14. The magnetic flux is conducted through one of the pole pieces 18 to medium 12 via the tip of the polepiece. The magnetic flux circuit is completed by the return of the magnetic flux from medium 12 to the yoke via the other pole piece. Changes in the magnetic flux caused by varying the electrical current carried through the coil are recorded as magnetic transitions on medium 12. During reading, as head 10 is passed over a dipole pair of magnetic transitions, or "di-bit" 15, 16 on medium 12, magnetic flux emanating from positive transition 15 is conducted up through the one of the pole pieces 18 and returned by the other pole piece to the negative transition 16. The magnetic flux conduction through yoke 14 induces a corresponding electrical signal in coil 16.
The amount of magnetic flux imparted to the yoke during writing by the coil depends upon the write current level, the number of coil turns, and the magnetic reluctance of the pole, among other factors. Similarly, the level of the voltage induced in the coil during reading depends upon factors such as the number of coil turns, the strength of the magnetic flux presented to the coil as it travels through the yoke, and the magnetic reluctance of the yoke. The magnetic flux-current relationship in a magnetic head is termed the inductive coupling between the yoke and the coil.
Referring to FIGS. 2A-2C, the ferromagnetic material of the pole pieces 18 includes numerous microscopic regions, called domains 20, within which magnetic dipoles 22 of the material are aligned. The material is formed (by deposition or annealing) in the presence of a directional magnetic field to cause the dipoles 22 of some of the domains 20 to become aligned with (i.e., oriented at an angle of 0 degrees to 180 degrees to) the magnetic field direction. The resulting alignment of the dipoles is also a function of the shape of the pole pieces. The direction at which the dipoles are aligned represents the preferred axis of magnetization of the pole piece and is called the easy axis 24. The dipole alignment of the domains 20 in the interior of the material and the domains 20 near the edges of the material is such that the magnetic flux generated by the dipoles 22 remains within the material in the absence of an externally applied magnetic field (FIG. 2A).
When magnetic flux is applied to the yoke either by passing current through the coil during writing or by passing the pole 18 over magnetic flux transitions on the medium 12 during reading, the magnetic flux is conducted through the material in one of two ways. One way is by so-called "wall motion", which occurs when the magnetic flux 26 is applied in a direction parallel to the easy axis 24 (FIG. 2B). The magnetic flux 26 causes domains 20 having dipoles 22 that are aligned with the direction of magnetic flux conduction 26 to increase in size (at the expense of those domains whose dipoles are disposed opposite to the magnetic flux direction) as magnetic dipoles from adjacent domains reorient themselves (e.g., by 180 degrees) to become aligned with the direction of magnetic flux conduction. As each domain grows in size, its walls 21 move to define new boundaries between the domains.
Magnetic flux conduction by wall motion is undesirable for several reasons. First, defects, such as impurities, in the material impede the movement of the domain walls 21. When a domain wall encounters an impurity, the impurity temporarily holds (i.e., "pins") the wall at the site of the impurity, preventing it from moving at the point of the impurity. The remainder of the wall continues to move, causing the wall to "stretch" and storing energy in the wall. When the wall stores sufficient energy to free itself from the hold of the impurity, the wall breaks free suddenly, releasing the stored energy as a burst of electrical noise (known as "Barkhausen noise") which obscures the information signal.
The applied magnetic flux must exceed a threshold to assure that the walls 21 will be able to gather enough energy to move past the impurities. As a result, magnetic flux conduction by wall motion is relatively unresponsive to the low magnetic flux levels with which thin film heads are typically used during read operations (that is, the material has low permeability at low magnetic flux levels.)
In addition, the domain walls 21 cannot be rapidly moved, and as a result, magnetic flux conduction by wall motion is unsuitable in applications in which high frequency changes in magnetic flux are encountered.
A second mechanism by which magnetic flux is conducted through magnetic material is by rotation of the magnetic dipoles 22 of the domains. This is done by applying the magnetic flux 26 in a direction transverse (such as perpendicular) to the easy axis 24 (FIG. 2C). Because domain wall motion is not relied upon to conduct the magnetic flux, "pinning" is not encountered and Barkhausen noise is eliminated. Further, the domain dipoles 22 need only rotate slightly to conduct the magnetic flux through the material. As a result, magnetic flux conduction by rotation is responsive to high frequency magnetic flux variations as well as low applied magnetic flux levels. That is, the magnetic permeability of the material is high even at low levels of applied magnetic flux.

Thin-film magnetic transducer with multiple yoke-coil interactions and elongated lateral yoke vias


A reflection soft X-ray microscope is provided by generating soft X-ray beams, condensing the X-ray beams to strike a surface of an object at a predetermined angle, and focusing the X-ray beams reflected from the surface onto a detector, for recording an image of the surface or near surface features of the object under observation.

The use of X-ray radiation in microscopy is known in the prior art. Such known X-ray microscopes typically are of the transmission mode type microscope, which include the source of X-rays on one side of the specimen or object to be viewed, and a radiation detector or imaging system on the other side of the object. Accordingly, only X-rays going through the material are detected. As a result, the use of such transmission type X-ray microscopes for viewing non-transparent or poorly transparent objects is limited, particularly with respect to soft X-ray lasers.
The technology related to X-ray microscopy has been greatly improved over the last ten years. Significant progress has been made in developing X-ray lasers, and synchrotron insertion devices, for providing increased brightness of laboratory X-ray sources.
Optical microscopy is limited to a resolution of about 3,000 angstroms, or about 0.3 micrometer. In lithographic systems used for inspecting integrated circuits, the capability for inspecting line widths of such circuits of less than 0.1 micrometers and below is now required. Electron microscopes can provide such resolution, but electron microscopes are slow to use for such inspection, and the electron beam can cause functional damage to the integrated circuit chip.
Skinner et al., in a paper entitled "Contact Microscopy With A Soft X-ray Laser", appearing in the Journal of Microscopy, Volume 159, part I, July, 1990, on pages 51 through 60, discusses the use of soft X-ray lasers for imaging live cells at high resolution, "thereby bridging the gap between electron microscope images of non-live cells that have undergone extensive specimen preparation, and low resolution but high fidelity images of live cells recorded with light microscopes." It is recognized that "to be of maximum utility to biologists, a soft X-ray laser contact microscope should be suitable for everyday use on fragile, living biological specimens." The paper also describes a system developed at Princeton University, Princeton, N.J., for generating soft X-ray laser beams. The installation of a contact microscope on a soft X-ray laser beam is shown. In this system, the soft X-ray laser beam is used to cause the shadow of a specimen to be recorded on photo-resist material.
Howells, et al., in a paper entitled "X-ray Microscopes", Scientific American, Volume 264, No. 2, February, 1991, pages 88 through 94, describes the state of X-ray microscopy, and the ongoing development of "soft" X-ray instruments, providing more than ten times better resolution than optical microscopes. It is indicated that "soft X-rays in the wavelength range of 20.0 to 40.0 angstroms (an angstrom is one ten-billionth of a meter), are sufficiently penetrating to image biological cells in many cases." The article goes on to describe the difficulty of focusing X-ray images and developments which led to the construction of a Fresnel zone plate for providing such focusing. Contact microradiography is described, as previously mentioned above, whereby an X-ray beam is passed through a sample to a resist (PMMA) material, causing a damage pattern in the resist material relating to details of the sample. Imaging X-ray microscopes are described whereby X-ray beams are passed through a condenser zone plate, for focusing the X-rays onto a region of a sample. The X-rays pass through the sample onto a micro-zone plate for focusing the X-rays into an image field that is picked up by a detector. A scanning X-ray microscope system is described whereby an X-ray beam is focused and scanned back and forth across a sample, with the scan beam being passed through the sample and detected by an X-ray counter.
A soft X-ray laser contact microscope system is described in Suckewer et al. U.S. Pat. No. 4,979,203. The described system uses an optical contrast microscope for inspecting and aligning a target prior to applying soft X-rays to the target for performing contact X-ray microscopy. An X-ray laser is used for providing the necessary soft X-ray beam.
Fields, et al. U.S. Pat. No. 3,702,933, entitled "Device and Method for Determining X-ray Reflection Efficiency of Optical Surfaces", teaches a method for determining the X-ray reflection efficiency and scattering characteristics of optical surfaces using much harder (shorter wavelength) X-ray radiation than the soft X-rays described above. As shown in the figure, X-rays of a known wavelength are generated by an X-ray source 11, and passed through a collimator 15, and therefrom passed through slits 17, for projection onto an area of a crystal monochromator 21 for diffracting the X-rays. The diffracted x-rays are then passed through slits 25, and projected onto a predetermined area of an optical test specimen 41. X-rays reflected off of the optical test specimen 27, are transmitted through a slit 33, and projected therefrom into an X-ray detector 31. The X-ray detector can be a Geiger-Muller counter. The intensity of the X-rays prior to and subsequent to reflection from the specimen 27 are compared for determining the efficiency of reflection of the optical surface of the test specimen 27. Suckewer et al. U.S. Pat. No. 4,771,430 shows an apparatus for enhancing soft X-ray lasing action through use of thin blade radiators in a target. Soft X-ray lasing action is generated in a defined plasma column. The plasma is produced by focusing a CO.sub.2 laser beam onto a carbon target. A magnetic field is used to compress the plasma into a thin column. A carbon disc in combination with carbon blades mounted perpendicular to the surface of the disc provides the target. The CO.sub.2 laser beam is directed to strike the surface of the disc for forming a plasma column. The column is cooled by radiation losses and heat conduction to the blade. The resulting soft X-rays are transmitted through a slot in the carbon disc.
Rocca U.S. Pat. No. 4,937,832 shows a method and apparatus for producing a soft X-ray laser beam in a capillary discharge plasma. As shown in FIGS. 1 and 2 thereof, the apparatus includes a pair of electrodes having axially oriented poles, respectively, for facilitating the exit of laser radiation. The electrodes are connected to a discharge circuit that includes a relatively large capacitor that is first charged to a given level, and then discharged across the electrodes. It is indicated that the power source can also be an electrical transmission line having a low impedance. Also discussed is the use of a high intensity magnetic field for containing the plasma.
Another Suckewer U.S. Pat. No. 4,704,718, similar to the above-described Suckewer patent, teaches the creation of a plasma column by focusing a CO.sub.2 laser pulse on a carbon target. A magnetic field is used to contain the plasma.
There are many other examples of soft X-ray generators and/or ultraviolet X-ray generators in the art. Other such references include U.S. Pat. Nos. 4,555,787, and 3,956,711.
Research is ongoing for providing improved sources of optics at short wavelengths, particularly wavelengths in the soft X-ray region from 1.0 nanometer to 30.0 nanometers wavelength. As previously indicated, laser sources and synchrotrons have provided soft X-rays for use in transmission X-ray microscopy. X-ray lasers provide a very high flux of short wavelength photons in very short pulses in single lines, whereas synchrotrons provide continuously tunable radiation. These sources of X-ray radiation tend to complement one another.
The present inventors recognized that by developing a reflection X-ray laser microscope, a step forward can be made in the field of the art for using such an apparatus in the field of lithography for inspecting integrated circuits, for example, and/or in the medical fields for analyzing biological specimens. They further recognized that the reflection coefficient for a number of biological materials is significant and differs substantially at soft X-ray wavelengths. They recognized that with a high flux of radiation from a soft X-ray laser, and through use of high sensitivity CCD (charge coupled device) detectors, a very compact reflection soft X-ray microscope can be provided. The inventors expect that such a microscope will provide magnification up to .times.100 with the resulting images recorded on CCD-array detectors, for example, having a pixel size in the order of 5.0 microns. Such a soft X-ray reflecting microscope is expected to have a resolution in the range of 0.05 microns.
It is further expected a soft X-ray laser source for use with the reflection X-ray microscope of the present invention will operate at a wavelengths of 18.2 nanometers (nm) with a beam energy of 1.0 to 3.0 mJ (millijoule) in a 10.0 to 30.0 nanosecond pulse. The laser can operate at shorter wavelengths (15.4 nm and 12.9 nm) with lower beam energy. A pumping CO.sub.2 laser pulse with an energy of 300.0 to 500.0 joules in 50.0 to 75.0 nanoseconds will create a lasing medium (plasma column) in a strong, magnetic field. Also, the repetition rate of the X-ray laser is three minutes.
The present inventors are scientists at the Princeton University Plasma Physics Laboratory (PPPL) (Skinner and Suckewer) and Mechanical and Aerospace Engineering Department (Suckewer) and Princeton X-ray Laser Inc. (Rosser), in Princeton, N.J., where soft X-ray laser development has been pursued for a number of years. In the March, 1987, issue of the "PPPL Digest", published by the Information and Administrative Services, Princeton Plasma Physics Laboratory, Princeton, N.J., the basics of soft X-ray technology existing in 1987 and various experimental results are discussed. In a later May, 1989 issue of the "PPPL Digest", a description of X-ray laser microscopy research at that facility is described. A composite X-ray laser microscope is shown and described for soft X-ray laser contact microscopy. Also, the basic principals of a soft X-ray laser are shown and described.

Reflection soft X-ray microscope and method