A substrate is coated with a hydrophilic layer(s) or coating(s) that includes, for example, amorphous carbon in a form of diamond-like carbon (DLC). In certain embodiments, the DLC inclusive layer may be doped with at least one polar inducing dopant (e.g., Boron, Nitrogen, and/or any other suitable polar inducing dopant) in order to make the layer more polar and thus more hydrophilic so as to have a lower contact angle xcex8 (e.g., no greater than about 10 degrees in certain embodiments, and more preferably no greater than about 8 degrees).

This invention relates to a hydrophilic coating including diamond-like carbon (DLC) provided on (directly or indirectly) a substrate of glass, plastic, or the like, and a method of making the same.
It is often desirable to provide a hydrophilic coating (e.g., anti-fog coating) on a substrate such as an automotive windshield, automotive window, automotive mirror, architectural mirror, bathroom mirror, or the like. Such coatings may reduce the likelihood of water drops deposited on the substrate taking globular shape(s), thereby enabling visibility to be improved. In other words, hydrophilic coatings function to reduce bead-like condensation on substrate surfaces (e.g., on the interior surface of an automotive windshield or window). A hydrophilic coating can reduce the formation of many tiny droplets of liquid, which can scatter light, on a surface (i.e., make condensation on a surface film-wise as opposed to droplet-wise).
Unfortunately, certain hydrophilic coatings are not as durable and/or hard as would otherwise be desired and thus are not efficient from a practical point of view for applications such as automotive windshields and/or windows. Furthermore, conventional hydrophilic coatings often cannot withstand high temperatures without breaking down or being damaged. The ability to withstand high temperatures is useful in applications such as automotive windshields where it may be desirable to anneal and/or bend a coated glass article at high temperature(s) after the coating has been deposited.
In view of the above, it is apparent that there exists a need in the art for (i) a coated article (e.g. coated glass dr plastic substrate) having hydrophilic properties, and a method of making the same, (ii) a hydrophilic coating capable of withstanding high temperatures (e.g., up to 600 degrees C., and/or even up to 700 degrees C. in certain embodiments) without being substantially damaged (e.g., burned/burning) or breaking down, and/or (iii) a protective hydrophilic coating for window and/or mirror substrates that is somewhat resistant to scratching, damage, or the like.
It is a purpose of different embodiments of this invention to fulfill any or all of the above described needs in the art, and/or other needs which will become apparent to the skilled artisan once given the following disclosure.
An object of this invention is to provide a durable coated article that it is less likely to attract or be affected by bead-like liquid condensation. Exemplary applications to which such hydrophilic coating(s) may be applied include, for example without limitation, automotive windshields, automotive backlites (i.e., rear vehicle windows), automotive side windows, architectural windows, mirrors, etc.
Another object of this invention is to provide a hydrophilic coating that can withstand high temperatures (e.g., up to about 600 degrees C., and more preferably up to about 700 degrees C.) without being substantially damaged (e.g., burning).
Another object of this invention is to provide a hydrophilic coating that is chemically inert to strong acids and/or bases, and may even act as a barrier against chemical attacks on the underlying substrate in certain embodiments.
Another object of this invention is to provide a scratch resistant hydrophilic coating for use in conjunction with a coated article.
Another object of this invention is to form or provide a hydrophilic coating by doping diamond-like carbon (DLC) with at least one polar inducing dopant(s) such as, for example, boron (B) and/or nitrogen (N). In certain embodiments, the atomic percentage of the polar inducing dopant(s) (e.g., B and/or N dopants, but not including H dopants that may or may hot be added because H is not a polar inducing dopant) is no greater than about 10%, more preferably no greater than about 5%, and most preferably no greater than about 4%. A polar inducing dopant is a dopant that causes DLC to become more graphitic (e.g., cause more sp2 bonds), as opposed to more tetrahedral (i.e., more sp3 bonds). Polar inducing dopant(s) tend to cause the DLC inclusive layer to be more polar, which in turn increases surface energy and thus provides for a more hydrophilic coating.
Another object of this invention is to provide a coated article, wherein a layer of the coating includes both sp2 and sp3 carbonxe2x80x94carbon bonds and has a wettability W with regard to water of at least about 700 mN/m, more preferably at least about 750 mN/m, and most preferably at least about 800 mN/m. This can also be explained or measured in Joules per unit area (mJ/m2).
Another object of this invention is to provide a coated article, wherein a layer of the coating includes both sp2 and sp3 carbonxe2x80x94carbon bonds and has a surface energy "Ugr"c of at least about 24 mN/m, more preferably at least about 26 mN/m, and most preferably at least about 28 mN/m.
Another object of this invention is to provide a coated article, wherein a DLC inclusive layer of the coating has an initial (i.e. prior to being exposed to environmental tests, rubbing tests, acid tests, UV tests, or the like) water contact angle xcex8 of no greater than about 10 degrees, more preferably no greater than about 8 degrees, even more preferably no greater than about 6 degrees, and most preferably no greater than about 4 degrees. The article""s initial contact angle xcex8 may be as low as 1-3 degrees in certain embodiments. In certain embodiments the article""s contact angle may increase over time upon exposure to environmental elements (as graphitic sp2 Cxe2x80x94C bonds wear off) while in other embodiments the article""s contact angle may decrease over time upon such exposure.
Another object of this invention is to provide a hydrophilic DLC inclusive layer for coating a substrate. In at least one portion of the layer no more than about 70% of the bonds in that portion of the layer are of the sp3 type, and more preferably no more than about 60% of the bonds are of the sp3 type. A substantial portion of the remainder of the bonds may be of the graphitic or sp2 type. The bonds in the layer may include, for example, carbonxe2x80x94carbon (Cxe2x80x94C) bonds, carbon-nitrogen (Cxe2x80x94N) bonds, carbon-boron (Cxe2x80x94B) bonds, and/or carbon-hydrogen (Cxe2x80x94H) bonds. The sp3 type bonds (e.g., Cxe2x80x94C bonds) function to increase the hardness and scratch resistance of the coating, while the graphitic sp2 type bonds (e.g., Cxe2x80x94C, Cxe2x80x94N and/or Cxe2x80x94B bonds) cause the coating to be more hydrophilic and have a lower contact angle.
Another object of this invention is to provide a coating which can make accumulated condensation form in a more film-wise manner; as opposed to a droplet-wise manner.
Still another object of this invention is to form amine (NH2) functional groups near the surface of a hydrophobic coating or layer so as to enhance hydrophilicity.
Yet another object of this invention is to fulfill any or all of the above listed objects and/or needs.
Generally speaking, this invention fulfills any or all of the above described needs or objects by providing a method of making a coated article comprising the steps of:
providing a substrate; and
depositing a hydrophilic layer including sp carbonxe2x80x94carbon bonds on the substrate in a manner such that the hydrophilic layer has an initial contact angle xcex8 with a drop of water thereon of no greater than about 10 degrees.
This invention further fulfills any or all of the above described needs and/or objects by providing a coated glass article comprising:
a glass substrate;
a hydrophilic layer including diamond-like carbon (DLC) with sp3 carbonxe2x80x94carbon bonds provided on said glass substrate; and
wherein said hydrophilic layer includes at least one dopant therein so as to cause the layer to have an initial contact angle xcex8 with a sessile drop of water thereon of no greater than about 10 degrees.
This invention further fulfills any or all of the above described needs and/or objects by providing a coated article comprising:
a substrate (e.g., glass or plastic);
a hydrophilic coating or layer including diamond-like carbon (DLC) provided on said substrate; and
wherein said hydrophilic coating or layer has an average hardness of at least about 10 GPa and has an initial contact angle xcex8 with a drop (e.g., sessile drop) of water thereon of no greater than about 10 degrees.
This invention further fulfills any or all of the above described needs and/or objects by providing a coated article comprising:
a substrate; and
a layer comprising amorphous diamond-like carbon on said substrate, said layer having a surface energy "Ugr"c of at least about 26 mN/m.
This invention still further fulfills any or all of the above described needs and/or objects by providing a coated article comprising:
a substrate; and
a layer comprising amorphous diamond-like carbon on said substrate, said layer having a contact angle xcex8 with a drop of water thereon of no greater than about 10 degrees.


A method for managing a flash memory including a plurality of blocks is provided. Each block includes a plurality of sets of a first page and a second page configured in pair. In response to a request for writing target data into a target block, at least one cache block is selected from the blocks. The target data is then written into the first pages in the at least one cache block. When a write-back condition is established, the target data is written from the cache block back to the target block.

1. Field of the Invention
The invention relates in general to a flash memory, and more particularly, to a method for managing a multi-level cell (MLC) flash memory.
2. Description of the Related Art
Different from a single-level cell (SLC) flash memory, an MLC flash memory is capable of storing at least two information bits in each storage unit. The term "multi-level" as used here means that each storage unit has more than two voltage values. Although the MLC flash memory is compromised by drawbacks of having shorter lifespan, higher power consumption, and a slower access speed, the MLC is still prevalent in various kinds of storage device because it has a greater capacity per unit cost than that of the SLC flash memory.
The MLC flash memory generally includes several blocks, each of which includes multiple sets of paired pages. Taking a page containing 32 pages as an example, the block possibly contains 16 most significant bit (MSB) pages and 16 least significant bit (LSB) pages. Each MSB page pairs with one LSB page to form a set of storage unit. One of the most critical drawbacks of the MLC flash memory is that, when an unexpected power-off or reset takes place while data are being written into a MSB page, not only data in the MSB page currently being written but also data originally stored in the paired LSB page corresponding to the MSB page are damaged, and vice versa.
Certain solutions for preventing or remedying the above error are available. In one conventional solution, an upper file system restores a file that is not completely written according to a system log. In another conventional solution, a writable region is limited within a single-type page (e.g., only the MSB page or the LSB page) between the paired pages—such approach suffers from a shortcoming of significantly reduced available capacity of a memory. In yet another conventional solution, data originally stored in a paired page B of a page A is duplicated to a backup region when writing data into the page A. Thus, when an error occurs in the write process, the system simply restores the data back to the page B from the backup region.

Electronic system and memory managing method thereof


A throat plate insert for a table saw is provided having a scale on the upper side thereof adjacent the region of the elongated slot for the circular saw blade. The scale provides an indication of the height of a specified diameter saw blade corresponding to the chordal length of a segment of saw blade protruding through the elongate slot.

Table saws are typically provided with a relatively large recessed throat opening in the table top surface through which the circular saw blade projects at various heights and angles selected by the user. The throat opening is typically filled by a throat plate insert which can be easily removed and changed as necessary. Most commonly, the original equipment of a throat plate provided with a table saw will have an elongated slot extending there through, somewhat larger than the kerf of the blade and having an elongate slot length slightly greater than the maximum chordal length of the portion of the saw blade extending above the saw table top surface at maximum height. The width of the elongate slot is typically larger than a conventional blade so that a table saw operator can install a thicker blade such as a carbide tip rip blade without interference. When a very thin kerf blade is installed, particularly at low blade height, very little of the elongated slot is filled with the portion of the blade extending above the height of the table which can pose a problem when cutting thin veneers or materials which easily chip. To address this problem, after market throat plates are available without any elongated slot formed therein at the time of the purchase. The user installs the throat plate on a table saw with the saw fully retracted and with the saw blade rotating raises the blade through the throat plate forming an elongate slot in situ. This type of throat plate is referred to as a "zero clearance throat plate".
Zero clearance throat plates are particularly useful when installing nonstandard diameter saw blades such as a dado head cutter which cuts slots having widths ranging from 1/8" to 3/16". Dado head cutters are frequently used to cut a groove in a workpiece having a precise width and depth. The width of cut is determined by the dado blade adjustment. The depth of the cut into the workpiece is determined by the blade height relative to the table. Blade height is typically set using a scale or blade height setting tool with a series of stepped notches formed therein. Accurately setting can be a tedious process frequently requiring trial and error and several iterations with requiring the user to make an initial cut, checking cut depth and adjusting accordingly.

Table saw throat plate with blade height scale


A mitt for keeping a hand of a fisher warm while fishing with a rod and spinning reel having a bale includes a shell and a slide fastener closure for the shell for selectively opening and cosing the shell. The shell, when closed by the closure, has a size and shape to encircle the hand. The shell includes openings for receiving (a) the rod so that opposite portions of the rod extend from opposite portions of the shell with a segment of the rod between the opposite portions being within the shell at a position to be gripped by the hand enclosed by the closed shell and (b) a strut connected to the segment and the reel so that the reel is outside of the closed shell. The shell includes a finger positioned and constructed to (a) receive and enclose a digit of the hand while the hand is enclosed by the closed shell at the position where the hand grips the rod segment and (b) enable the fisher's digit therein to manipulate the bale.

Experienced fishers have long been aware of the advantages of cool and cold weather fishing. However, cool and cold weather fishing is accompanied by the discomfort of cold hands for the fisher. Experienced fishers have generally disdained from the use of conventional gloves during cool or cold weather fishing because conventional gloves prevent the fisher from achieving maximum sensitivity to tugs on a rod or line by a fish. Experienced fishers find that maximum results are achieved if one of their hands has direct contact with the rod and/or line. Such direct contact cannot be achieved with conventional gloves or mitts.
To overcome these problems, I previously invented a mitt for rods having casting reels. This mitt, disclosed in my U.S. Pat. No. 4,727,675, includes a thermally insulated shell in which the hand of the fisher and the casting reel and a handle portion of the rod are completely enclosed. The casting rod and fishing line from the reel extend through apertures in the shell.
While this prior art structure is quite satisfactory for rods including casting reels, it cannot function as a mitt for keeping the hand of a fisher warm while the fisher is fishing with a rod and spinning reel having a bale. The bale must be manipulated by a digit of the hand gripping the rod. The reel is too cumbersome to be located in the mitt and hand-eye coordination is frequently important in manipulating the bale. If the bale were in the mitt such coordination could not be attained. In addition, it is not feasible for the fishing line from the spinning reel to be within the mitt confines.
It is, accordingly, an object of the present invention to provide a new and improved mitt for keeping the hand of a fisher warm while fishing with a rod and spinning reel having a bale.
It is another object of the present invention to provide a new and improved mitt for keeping the hand of a fisher warm while fishing with a rod and spinning reel having a bale, wherein the mitt enables the bale and fishing line, both of which are outside of the mitt, to be manipulated from within the mitt by a digit of the fisher.
It is an additional object of the present invention to provide a new and improved mitt for keeping the hand of a fisher warm while fishing with a rod and spinning reel having a bale wherein the hand of the fisher directly grasps the rod, to maximize the sensitivity of the fisher to tugs by prey that are coupled from the line to the rod, while enabling a digit of a hand of the fisher to manipulate the bale and line, even though the bale and line are outside of the mitt.


To reduce prefetch overshoot when prefetching partial data sets along the path from input-output bus to system memory, a prefetch field is used to communicate the amount of data that a prefetching entity upstream may prefetch. Utilizing a prefetch field in such a manner reduces the fetching of unneeded data past the end of the requested data, resulting in overall increased system performance.

The present invention pertains to improving data bus efficiency. More particularly, the present invention pertains to reducing the amount of data that is prefetched beyond what is needed by a system component (i.e., overshoot).
In a typical mid-range or high-end server system, a number of components are coupled to an Input/Output (I/O) bus, which in turn is coupled to system memory. The physical size and number of interconnected components in such systems can often lead to large latency periods when components on the I/O bus are writing data to and reading data from the system memory. As components are added this problem is exacerbated.
It is therefore desirable to have a system for improving bus efficiency and reducing latency as well as providing additional benefits.

Method and system to improve prefetching operations


An electromagnet control apparatus having a remote control switch assembly switchable between a number of positions representing full, variable, residual and zero levels of magnetization. Means are provided for causing the electromagnet to be fully energized for several seconds before being dropped to the residual level of magnetization whenever the switch assembly is switched to a residual setting.

This invention relates to demagnetizing apparatus for electromagnets and workpieces held thereby and more particularly to such apparatus which is capable of demagnetizing a plurality of workpieces so as to allow removal of each workpiece without affecting the other workpieces.
In many environments in which an electromagnet is used for holding a workpiece, it is necessary to provide some means for demagnetizing the electromagnet and a workpiece held thereby before the workpiece can be readily removed from the holding magnet. Otherwise, the residual magnetism left in both the magnet and the workpiece may be sufficient to inhibit easy removal of the workpiece from the magnet. One example of such a situation is where an electromagnetic chuck is used for holding one or a plurality of workpieces for a grinding operation.
U.S. Pat. No. 4,370,693, assigned to the assignee of the present invention and incorporated herein by reference, discloses a demagnetizing apparatus for a workpiece-holding electromagnet. This demagnetizing apparatus includes switching means which can switch the magnetic hold of the electromagnet between various states of magnetization corresponding to full, variable, residual, and zero levels of magnetization.
The embodiment disclosed by U.S. Pat. No. b 4,370,693 specifically includes four switch positions designated FULL, VARIABLE, RESIDUAL and RELEASE. In the FULL switch position, maximum rectified a.c. power is transmitted to the electromagnetic chuck winding in order to provide the greatest holding power for the workpiece. When the switch is in the RESIDUAL position the holding power of the electromagnet is reduced, but not demagnetized, to a level that would allow one of a collection of workpieces to be removed when a multiplicity of workpieces are being machined or ground down at one time.
In some cases, it may be desirable to firmly hold a smaller workpiece without exerting FULL holding power, e.g., where such power might distort the workpiece. The VARIABLE setting is provided for this purpose. This switch position provides a preselected level of magnetization, the level typically selected to be less than FULL but substantially greater than the so-called RESIDUAL setting.
If it is desired to completely release the workpiece or workpieces, the control switch S1 may be moved to the RELEASE position to effect automatic demagnetization of the electromagnetic chuck and any permeable workpiece held thereby.
The RESIDUAL setting does not, however, always provide sufficient magnetism to hold the workpiece in place. When the chuck control is switched from a low level of VARIABLE holding to the RESIDUAL mode, the resulting residual magnetic holding force may be less than the minimum holding force intended to be supplied by the RESIDUAL mode. As a result, an operator may have handling problems with the workpieces since the non-maneuvered workpieces may shift.
Among the several objects of the present invention may be noted the provision of such an apparatus which will insure that a chuck will always achieve maximum residual magnetic holding force when in the RESIDUAL mode; the provision of such apparatus which is highly reliable and which is of relatively simple and inexpensive construction. Other objects and features will be in part apparent and in part pointed out hereinafter.

Chuck control for a workpiece holding electromagnet


A power detector for detecting the magnitude of a radio frequency (RF) signal comprises a detector transistor (V1) which provides an output signal (DC-OUT) in dependence upon the input RF signal. The detector transistor is biased with a biasing circuit which comprises two transistors (V2,V3) in a feedback loop coupled to the base of the detector transistor (V1). The detector can be used as both current and voltage amplifier. One of the transistors (V3) in the feedback loop provides temperature compensation.

The present invention relates to a power detector for detecting the magnitude of a radio frequency (RF) signal.
Power detectors are used, for example, in control circuits at the output of RF signal power amplifiers. Early power amplifiers had only one output power level, that was tuned to the desired level during the production. However, it is now common to reuse radio channels in some RF communications systems, for example, in cellular radio telephone systems. To avoid interference between the two RF signal power amplifiers using the same channel, the two operate at different power levels, and, therefore it is desirable to be able to select different power levels from a number of available power levels. Power detectors are provided in the control circuitry for the RF signal power amplifiers used in such systems. One such detector comprises a rectifier diode the voltage from the RF signal power amplifier being coupled to the anode at the diode, and the cathode providing a rectified voltage proportional to the coupled voltage. The voltage from the detector is coupled to an amplifier and a comparator controlling a current amplifier, from where the current is supplied to the end stage amplifiers. Thus amplifiers and a circuit generating and regulating the current are needed in addition to the power detector.
In order for the power detector to operate at low power levels the rectifier diode must be biased in some way, because the diode has a certain threshold voltage. This threshold voltage is also temperature dependant, so that the biasing must also take into account changes in the threshold voltage caused by temperature.
In order to compensate for changes in the threshold voltage caused by temperature variations it is known to use a second diode, which is forward biased and from which a biasing voltage is coupled through a resistor to the rectifier diode. Variations of the rectifier diode threshold voltage due to temperature changes is compensated for because the voltage over the second diode changes in the same manner, if the diodes are at the same temperature and if they have equal temperature coefficients.

Power detector that employs a feedback circuit to enable class B operation of a detector transistor


A crib includes four vertical corner posts; side support beams and end panels which interconnect the vertical corner posts in a rectangular configuration; support shoulders for supporting a mattress between the vertical corner posts; a drop side movable in a vertical direction between opposite pairs of vertical corner posts, each drop side including an upper and lower rail; upper and lower slide members secured to opposite ends of each upper and lower rail for slidably guiding the drop sides in the vertical direction; a kick bar rotatably secured to the lower rail of each drop side and including rod ends; a lower bracket secured to the lower ends of the vertical corner posts for guiding the lower slides in the vertical direction and for retaining the drop sides in a raised or lowered position, each lower bracket including an upper and lower slot such that the drop sides are retained in the raised position when the rod ends are positioned in the upper slots and are retained in the lowered position when the rod ends are positioned in the lower slots; an upper bracket secured to the upper ends of the vertical corner posts for guiding the upper slides in the vertical direction; and a spring connected between each kick bar and its associated lower rail for biasing the kick bar in a rotatable direction so as to bias the rod ends thereof into engagement with one slot.

The present invention relates generally to cribs, and more particularly, is directed to a crib having a novel drop side lock.
Infant cribs which include drop sides or gates are well known. In such case, a mechanism is provided for locking the drop side in a raised position which prevents escape by the infant, and a lowered position which permits access to the infant by an adult. Since infants are involved, safety precautions must be taken to ensure that the drop side will not accidently or inadvertently become unlocked and thus, accidently fall.
For example, in U.S. Pat. No. 4,530,528 to the same inventor herein, and the entire disclosure of which is incorporated herein by reference, each of the upper and lower rails of each drop side has an end connected to a slide member. The slide members are slidably held on respective guide members that are secured to the vertical corner posts. A spring biased lock pin is provided on each upper slide member for removable insertion into respective holes in the upper guide members in order to releasably lock the drop side between a raised and lowered position. See also U.S. Pat. Nos. 4,639,956 and 4,706,312, both to the same inventor herein, for a similar description and the entire disclosures of which are also incorporated herein by reference.
U.S. Pat. No. 4,715,075, also to the same inventor herein, and the entire disclosure of which is incorporated herein by reference, discloses an arrangement in which only the upper portion of the side rail is pivoted down in order to obtain easy access to the infant. However, upper locking mechanisms are also provided with this type of crib.
It is also known to provide a drop side with a kick bar mechanism mounted to the lower rail of the drop side. In such known cribs, a metal, vertically oriented guide rod is secured in spaced and parallel relation to each vertical corner post. The upper and lower rails of each drop side are provided with holes through which the guide rods extend, in order to slidably mount the drop sides between the raised position which prevents escape by the infant, and the lowered position which permits access to the infant by an adult. In the lowered position, the lower rails merely rest on the curved lower ends of the guide rods.
In order to secure the drop sides in the raised position, a spring biased kick bar is provided along the length of each lower rail. The kick bar includes a central foot kick and rod ends that protrude past the ends of the lower rails. In the raised position, the rod ends engage with hooks secured to the vertical corner posts. To lower the drop side, the drop side is raised slightly so that the rod ends escape the hooks, and then the central foot kick is pushed inwardly against the spring force. Thereafter, with central foot kick pushed inwardly, the drop side is lowered to a point where the rod ends are below the hooks. The foot kick can then be released, and the drop side lowered along the guide rods. At such time, the spring force will return the kick bar to its original position. On the other hand, during the raising of the drop side, the rod ends will engage and ride over the hooks, whereupon they will be forced by the spring action into engagement with the hooks to hold the drop side in the raised position.
However, there is the necessity of providing a slide arrangement which is separate and distinct from the locking mechanism for locking the drop sides in the raised position. Therefore, the construction of such a crib is undesirable.


An electronic tag reading device includes an antenna for transmitting wireless signals to an electronic tag for reading information stored in the electronic tag, an electronic tag reader electrically coupled to the antenna, the electronic tag reader supplying signals to the antenna and receiving signals from the antenna for reading information stored in the electronic tag, and a movable stage connected to the antenna and configured to move the antenna when the antenna is transmitting wireless signals during a tag reading process of the electronic tag reader and stop moving the antenna when the antenna is not transmitting wireless signals during the tag reading process.

In the related art, a radio tag reading device reads information from a radio frequency identification (RFID) tag using an RFID reader with a moving antenna. The RFID tags can be attached to items of merchandise or other commodities for tracking and inventory control.
In a radio tag reading device, a transmission time limit for radio wave emissions may be regulated by law. Therefore, if the position of the antenna moves after the transmission of radio waves has been stopped due to the transmission time limit, there can be a problem in that the reader may miss a portion of its intended reading range and thus certain tags may be missed.


A cathode-ray tube includes an envelope in which a panel portion, a funnel portion, and a neck portion are integrally formed, and a conductor film and a deflecting yoke mounted on an outer surface of the funnel portion. A strip-type electric field reducing piece has a coated portion coated with an insulator, and an exposed conductive material portion. The coated portion is disposed between the funnel portion and the deflecting yoke, and the conductive material portion is connected to the conductor film.

1. Field of the Invention
The present invention relates to a cathode-ray tube and a display unit using the cathode-ray tube.
2. Description of the Prior Art
FIG. 1 is a side, partially cut-away view showing a conventional cathode-ray tube (hereinafter abbreviated as CRT). In the drawing, reference numeral 1 means the CRT, 2 is a dish-like panel portion, and 3 is a funnel-like funnel portion having a neck portion 3a. The panel portion 2 and the funnel portion 3 are integrally made of, for example, glass to form an envelope 100 of the CRT 1. Reference numeral 4 means an electron gun disposed in the neck portion 3a, 5 is a partially cylindrical aperture grill disposed along the panel portion 2 in the envelope 100, and 6 is a three-color fluorescent substance applied to an inner surface of the panel portion 2 to emit any one of blue light, green light, and red light. Reference numeral 7 means an electronic beam emitted from the electron gun 4 to emit corresponding light in the three-color fluorescent substance 6. The electron gun 4 includes three beam emitting apertures to emit the electronic beam 7 corresponding to each of the above three colors.
Reference numeral 8 means a deflecting yoke for the electronic beam 7 scanning on the fluorescent substance 6, 8a is a horizontal deflection coil of the deflecting yoke 8, and 8b is a lead wire to feed horizontal deflection current to the horizontal deflection coil 8a. The horizontal deflection current is sawtooth current typically ranging from 15 to 100 kHz (refer to FIG. 2).
Reference numeral 9 means a flyback transformer (hereinafter abbreviated as FBT) to supply dc voltage ranging from 23 to 27 kV, 10a is a conductor film of tens .OMEGA./.quadrature., referred to as external conductive coating, which is applied to an outer surface of the funnel portion 3, and 10b is a conductor film of tens .OMEGA./.quadrature., referred to as internal conductive coating, which is applied to an inner surface of the funnel portion 3. Here, the expression of n .OMEGA./.quadrature. indicates that n .OMEGA. appears between any two points on the conductor film. The external conductive coating 10a and the internal conductive coating 10b are disposed to interpose the funnel portion 3 therebetween, and form one capacitor (of, typically, 2000 pF), thereby forming a smoothing circuit for high dc voltage from the FBT 9.
In FIG. 2, an upper graph shows the horizontal deflection current which is rapidly changed for a flyback period T.sub.R. Therefore, as shown in a lower graph of FIG. 2, pulse voltage of about 1200 V is caused for the flyback period T.sub.R to be applied across the horizontal deflection coil 8a. In FIG. 2, a period T.sub.S means one scanning period.
Capacitance (typically ranging from 50 to 100 pF) is formed by the horizontal deflection coil 8a and the internal conductive coating 10b serving as the conductor film of tens .OMEGA./.quadrature., which is applied to the inner surface of the funnel portion 3. Through the capacitance, pulsed voltage caused for the flyback period T.sub.R induces in the internal conductive coating 10b pulse voltage of several volts or less, which is identical with that shown in the lower graph of FIG. 2. An anode button 11 is connected to the FBT 9 for supplying the dc voltage ranging 23 to 27 kV, and serves as a high-voltage receive of the CRT 1. The internal conductive coating 10b is electrically connected to the anode button 11 and the aperture grill 5 serving as a color selecting mechanism.
Consequently, the aperture grill 5 receives the dc voltage ranging from 23 to 27 kV from the FBT 9, and the voltage induced by the pulse voltage having horizontal deflection cycle (of 15 to 100 kHz), which is developed across the horizontal deflection coil 8a of the deflecting yoke 8, resulting in a variation in voltage as shown in FIG. 3. In FIG. 3, reference mark T.sub.H means a horizontal cycle, V.sub.1 is dc voltage of aperture grill voltage ranging from 23000 to 27000 V, and V.sub.2 is fluctuating voltage of several volts.
An ac power line 12 is emitted from the panel portion 2 of the CRT 1 in a forward direction. The MPR standards are provided in Sweden as a guideline for restriction of a leakage electric field due to the ac power line 12. According to requirement in the standards, a leakage electric field of 2.5 V/m should be for a distance of 50 cm from a tube surface in a band width ranging from 2 to 400 kHz.
It is known that many electric fields in the band width from 2 to 400 kHz are caused due to horizontally deflected flyback pulses, and the electric fields are mainly caused due to the pulses from the deflecting yoke 8.
In areas other than a front surface of the CRT 1, it is possible to effectively shield the leakage electric fields by a shield material including, for example, a metallic plate. However, on the front surface of the CRT 1, it is impossible to directly employ, for example, the metallic plate for shield because an image must be displayed without an obstacle.
On the other hand, the front surface of the panel portion 2 is charged by high voltage applied to the CRT 1, and dust in the air thereby adheres to the front surface of the panel portion 2. In order to avoid the adhesion, a transparent conductive film is formed on a transparent panel which is disposed on the front surface of the CRT 1 or ahead of the CRT 1, and the transparent conductive film is grounded (a transparent conductive film method). In the transparent conductive film, a considerable shield effect can be expected on an electric field irradiated from the front surface of the CRT 1. However, formation of the transparent conductive film requires high cost.
Further, in another method of reducing the leakage electric field, the external conductive coating 10a is applied onto the funnel portion 3 of the CRT 1 to extend to the deflecting yoke 8 (external conductive coating extending method). FIG. 4 is an exploded perspective view showing a structure employing the external conductive coating extending method. In the drawing, a funnel-like insulator 16 is superimposed on an outer surface of a funnel-like conductive material 15, and is disposed between the funnel portion 3 and the deflecting yoke 8.
However, in the structure, there is the constraint that the conductive material 15 and the insulator 16 must be mounted before the deflecting yoke 8 is incorporated into the funnel portion 3. Further, a strip-type magnetic body referred to as spoiler is generally inserted into a gap between the funnel portion 3 and the deflecting yoke 8 to correct erroneous convergence caused in the process of ITC adjustment. However, the conductive material 15 and the insulator 16 result in difficult insertion of the magnetic body and difficult assembling operation. Besides, the funnel-like conductive material 15 and the insulator 16 decrease air permeability to increase a temperature of the deflecting yoke 8. As a result, there is a fear that reliability deteriorates.
The conventional cathode-ray tubes employing the external conductive coating extending method are disclosed in, for example, Japanese Patent Publication (Kokai) No. 5-54834, and Japanese Patent Publication (Kokai) No. 5-283020.
The conventional cathode-ray tube has the above structure in which the transparent conductive film method or the external conductive coating extending method is employed to reduce the leakage electric field from the panel portion. However, there are problems in that the former method results in high cost, and the latter method deteriorates reliability due to the increase in temperature of the deflecting yoke, and decreases an incorporation efficiency during the ITC adjustment.

Cathode-ray tube and display unit using the cathode-ray tube


An equipment status monitoring system (10) and method of operating includes first (40) and second (50) microwave mirrors in a plasma processing chamber (20) each forming a multi-modal resonator. A power source (60) is coupled to the first mirror (40) and configured to produce an excitation signal. A detector (70) is coupled to at least one of the first mirror (40) and the second mirror (50) and configured to measure an excitation signal. At least one of the power source (60) and the detector (70) is coupled to a divergent aperture (44).

1. Field of the Invention
The present invention generally relates to fabrication of integrated circuits in the semiconductor industry.
2. Discussion of the Background
The fabrication of integrated circuits (IC) in the semiconductor industry typically employs plasma to create and assist surface chemistry within a material processing chamber necessary to remove material from and deposit material to a substrate. In general, plasma is formed within the processing chamber under vacuum conditions by heating electrons to energies sufficient to sustain ionizing collisions with a supplied process gas. Moreover, the heated electrons can have energy sufficient to sustain dissociative collisions and, therefore, a specific set of gases under predetermined conditions (e.g., chamber pressure, gas flow rate) are chosen to produce a population of charged species and chemically reactive species suitable to the particular process being performed within the chamber (e.g., etching processes where materials are removed from the substrate or deposition processes where materials are added to the substrate).
The semiconductor industry is constantly striving to produce smaller ICs and to increase the yield of viable ICs. Accordingly, the material processing equipment used to process the ICs have been required to meet increasingly more stringent performance requirements for etching and deposition processes (e.g., rate, selectivity, critical dimension).

Apparatus and method for improving microwave coupling to a resonant cavity


The present invention relates to the technical field of synthetic aperture radar, and in particular to a ground-based interference synthetic aperture radar-based atmospheric phase compensation method. The present invention first uses the inverse fast Fourier transform algorithm to rapidly and effectively realize the focusing in the range and cross-range dimension. Then a triple threshold method which combines coherence coefficient, amplitude, and amplitude dispersion index is used to select reliable PS points. Finally, under a full consideration of the spatial correlation of the atmospheric phase, the atmospheric phase is estimated by using a two-dimensional-polynomial model. The present invention can rapidly and accurately estimate and compensate the atmospheric phase, is helpful in improving the accuracy of GB-InSAR real-time measurement, and valuable and universal in practical application.

Ground-based Interferometric Synthetic Aperture Radar (GB-InSAR) has been widely used in the field of deformation monitoring, such as landslide monitoring, glacier monitoring, and dam monitoring etc. GB-InSAR technology realizes high range resolution and cross-range resolution of radar image by stepped frequency continuous wave (SFCW) technology and synthetic aperture technology, respectively. Also, the GB-InSAR technology has the advantages of short revisiting time, flexible observation angle, and high stability of the sensor platform etc., so it has great application value in remote sensing deformation measurement. However, although the GB-InSAR measurement has high accuracy, it is easily disturbed by atmospheric phase screen (APS) or affected by system noise, and atmospheric disturbance has the greatest effect, such that the reliability and accuracy of deformation measurement will be seriously decreased. Therefore, it is necessary to compensate the atmospheric phase.
Existing APS estimation methods mainly include model-based methods and meteorological data methods. In the model-based methods, APS is usually modeled as a polynomial function of the distance, and is further estimated by using permanent scatterer (PS) technology, namely, the estimation is performed by selecting target points that can keep high correlation in a long period of time from the SAR images, or manually setting ground control points (GCPs). However, in fact, the atmospheric phase is not only a function of distance, but also a function of cross-range. In the meteorological data methods, the estimation of APS is performed according to the measured atmospheric parameters such as temperature, humidity, and pressure etc. The estimation performance of the meteorological data method depends on the accuracy of the meteorological data measurement, and when the atmospheric parameters change greatly along the monitoring scene, such method is no longer applicable.

Ground-based interferometric synthetic aperture radar-based atmospheric phase compensation method

UNIVERSITY OF ELECTRONIC SCIENCE AND TECHNOLOGY OF CHINA


A stage apparatus includes a stationary support plate; a stage member provided on the stationary support plate so as to move on a reference plane parallel with the stationary support plate; Y-direction magnetic flux generating devices secured to one of the stationary support plate and the stage member; and Y-direction moving coils secured to the other of the stationary support plate and the stage member, the Y-direction moving coils receiving magnetic flux from the Y-direction magnetic flux generating devices so as to generate a driving force in a specific Y-direction between the Y-direction magnetic flux generating devices and the Y-direction moving coils. The Y-direction moving coils are secured to the stage member so that the Y-direction moving coils at least partly overlap each other in an X-direction, which is parallel with the reference plane and perpendicular to the Y-direction, and do not overlap in the Y-direction.

1. Field of the Invention
The present invention relates to a stage apparatus which is movable on a specific plane and an image movement correction apparatus for a camera using the stage apparatus.
2. Description of the Related Art
In a known image movement correction apparatus for a camera, a movable portion, such as a circuit board, which supports a correction lens or an image pickup device, is supported to linearly move relative to a stationary support plate in orthogonal X and Y directions perpendicular to an optical axis (Japanese Patent No. 2,641,172). It is also known that the direction in which the movable portion is moved is corrected if the movable portion and the stationary support plate rotate about the optical axis during the focusing operation (Japanese Unexamined Patent Publication No. 8-152661).
However, in image movement correction apparatuses of the prior art, since the movable portion is moved linearly only in the X and Y directions, it is impossible to correct an image movement due to a camera shake which includes a rotational movement of the camera. However, if a mechanism for correcting the rotational movement of the camera is additionally provided, the image movement correction apparatus is made large and heavy.

Stage apparatus and image movement correction apparatus for camera using stage apparatus


Seal coating compositions and method of applying same, to metallic surfaces, particularly aluminum or alloys thereof, containing a previously formed protective coating on the metal surface, to provide for improved corrosion resistance beyond that provided by the previously formed protective coating. Aqueous solutions of the seal coating components are applied to the metal surface containing the previously formed coating which is subsequently rinsed and dried to provide metal articles having improved resistance to corrosion.

1. Field of the Invention
This invention relates to the field of protective and/or surface treatment of articles, particularly metal surfaces and to surface treatment compositions employed as solutions or dispersions and methods of using these compositions. The compositions coated on the metal surfaces provide improved corrosion resistance and adhesion of any subsequent overlaying coatings.
2. Statement of Related Art
In the art of treating metal surfaces, it is common practice to improve the corrosion resistance characteristics and bonding of subsequent coatings to the metal surface by depositing or coating the metal surface with a protective coating or film. In order to improve the qualities of the already applied protective coating, it is common to provide a second or subsequent coating after the initial protective coating has been formed on the metal surface. This second coating further enhances the corrosion resistance of the unpainted metal surface and to prepare the surface for reception of a final finish coating where one is to be employed, such as a paint, enamel or lacquer. In U.S. Pat. No. 3,912,548, assigned to Amchem Products, Inc., there is described an aqueous zirconium compound-polyacrylic acid coating composition which is applied to a metal surface already having deposited thereon a conversion coating, which results from treatment of a base metal surface with aqueous solutions which react with the metal surface. The conversion coatings described in the patent are chromate or phosphate coating.
Conversion coatings which include hexavalent chromium have been widely used in the past to protect metals such as iron, zinc, magnesium and aluminum or alloys of aluminum including those with manganese, copper, zinc, silicon and magnesium. While such chromium coatings provide good corrosion resistance properties, recent attempts have been made to produce acceptable chromate-free coatings because of growing concern regarding pollution effects of the chromate and phosphate, particularly hexavalent chromium, discharged into rivers and waterways, which results in extensive waste treatment procedures being required to control their discharge. In U.S. Pat. No. 3,964,936, assigned to Amchem Products, Inc., there is reported and described various attempts to develop chromium-free aluminum coating solutions and describes a zirconium coating solution, which may also include boric acid. In describing coating solutions Examples 29 and 30 in the patent, which include sodium nitrate and cobalt nitrate, Co (NO.sub.3).sub.2 .multidot.6H.sub.2 O, reference is made also to U.S. Pat. No. 3,682,713, which includes a sodium nitrite component in a coating solution for steel and galvanized steel as well as aluminum.
U.S. Pat. Nos. 4,963,596 and 4,970,264 assigned to Henkel Corporation, describe the use of modified polyphenol compounds, which may be used in the "post-treatment" of conversion coated metal surfaces.


An actuator (7) comprises a housing (8) which contains a screw mechanism (9) and a motor (10) which is drivably connected to the screw mechanism (9), said screw mechanism (9) providing a linear movement in response to a rotational movement of the motor (10), and comprising a screw (12) and a nut (13) one of which is supported rotatably with respect to the housing (8) by means of a rolling element bearing (25, 62). Support means (22, 61) have been provided which extend axially with respect to the screw mechanism (9), said support means (22, 61) engaging the housing (8), and supporting the screw mechanism (9) so as to take up the axial loads exerted on said screw mechanism (9).

The invention is related to an actuator, comprising a housing which contains a screw mechanism and a motor which is drivably connected to the screw mechanism, said screw mechanism providing a linear movement in response to a rotational movement of the motor, and comprising a screw and a nut one of which is supported rotatably with respect to the housing by means of a bearing.
Such actuator is known from WO-A-9603301.
Having regard to the fields of application of these actuators, it is generally desired to obtain limited overall dimensions and low weight in combination with a low cost price. For instance, actuators of this kind are applicable in disc brakes for the automative industry. A relatively low weight of the actuator is of importance with respect to minimizing the unsprung weight of a vehicle.
The object of the invention is to provide an actuator which is improved with respect to the criteria before. This object is obtained in that support means are provided which extend axially with respect to the screw mechanism, said support means engaging the housing, and supporting at least one of the screw mechanism and the motor.
The support means enable a stable positioning or centring the actuator, and provide an accurate and repeatable displacement in response to control signals. Moreover, the support means may partly or completely be accommodated within the screw mechanism, whereby the overall dimensions are reduced.
The support means as contained in the actuators according to the invention may be connected to the housing in several ways. According to a first embodiment, the support means may comprise a shaft or tube member which is stationary fixed to the housing, the rotor and one of the nut or screw being rotationally supported with respect to the shaft or tube member.
Said shaft or tube member at one end extends into the screw mechanism, and carries a support bearing at or near said end for supporting axial loads exerted on the screw mechanism.
For an improved load support function, the support bearing may be carried out as a four-point contact bearing, the loading angle of the pair of contact points which take up the axial compressive force on the screw mechanism being smaller than the other loading angle. Furthermore, the support bearing is preferably a full complement bearing.
According to a particularly preferred embodiment, the support bearing is situated within the screw mechanism. Said support bearing rotatably supports the screw of the screw mechanism.
Furthermore, the screw may be ring-shaped or sleeve-shaped, and the outer race of the support bearing may be partly of fully integrated in the inner surface of said ring-shaped or sleeve-shaped screw.
Moreover, the inner race of the support bearing may be partly or fully integrated in the shaft or tube member.
For purposes of controlling the actuator load and thus the brake force, the shaft or tube member engages the housing through a load cell. Said load cell may comprise a piezo-electric material, or a strain-gauge embedded in a foil.
According to a second, alternative embodiment the support means comprise a shaft or tube member which is rotatably connected to the housing. Said shaft or tube member is arranged for transferring a rotational movement between motor and screw mechanism. In a simple embodiment, the rotor is connected to the shaft or tube member.
The shaft or tube member is supported with respect to the housing by means of a support bearing for transferring axial forces exerted on the screw mechanism. In this case as well, the support bearing engages the housing through a load cell.
The screw may be fixed to the shaft or tube member; alternatively, the nut is fixed to the shaft or tube member.
In a preferred embodiment, the screw is axially displaceable and non-rotatable with respect to the housing, and the nut is rotatably supported with respect to the housing by means of a support bearing. Said support bearing may engage the housing through a load cell.
The motor may engage the screw mechanism through a reduction gear mechanism. Said reduction gear can be contained in a reduction gear module.
The invention is also related to a brake calliper for a disc brake, comprising a claw piece carrying two opposite brake pads between which a brake disc can be accommodated, and an actuator for displacing the brake pads towards and from each other, said actuator comprising a housing connected to the claw piece and containing a screw mechanism and a motor which is drivably connected to the screw mechanism, said screw mechanism providing a linear movement in response to a rotational movement of the motor, and comprising a screw and a nut one of which is supported rotatably with respect to the housing by means of a bearing. According to the invention, said actuator is provided with support means which extend axially with respect to the screw mechanism, said support means engaging the housing, and supporting the screw mechanism.
Several further embodiments are conceivable as well. For instance, all or some of the components of the actuator may be obtained by means of a hard turning operation, or may be coated with a diamond-like carbon coating. In this way, wear may be reduced. Also, the actuator may be lubricated and sealed for life.
The gears applied in the gear reduction may consist of a, metallic, a non-metallic or a powder material.
The drive means can be electrical, hydraulic, pneumatic or mechanically induced by e.g. a spring.
The support shaft or tube may comprise an external flange which forms a unity therewith, or which is (laser)welded, bolted, glued, soldered etcetera thereto.
The recirculating means for the balls or rollers of the ball screw mechanism (grooves, holes or tubes) may be located in the nut or the screw.

Actuator having a central support, and brake calliper comprising such actuator

SKF Engineering and Research Centre B.V.


Various embodiments of reinforced mirror microstructures for a surface micromachined optical system are disclosed. Multi-layered and structurally reinforced mirror microstructures are disclosed, including both two and three-layer microstructures. Adjacent structural layers in these multi-layered mirror microstructures may be structurally reinforced and interconnected by a plurality of vertically disposed columns, or by a plurality of at least generally laterally extending rails or ribs, or some combination thereof. Various embodiments of a single layered mirror microstructure with a structural reinforcement assembly that cantilevers from a lower surface thereof is also disclosed.

The present invention generally relates to surface micromachined optical systems and, more particularly, to such systems that include at least one structurally reinforced surface micromachined mirror microstructure.
There are a number of microfabrication technologies that have been utilized for making microstructures (e.g., micromechanical devices, microelectromechanical devices) by what may be characterized as micromachining, including LIGA (Lithographie, Galvonoformung, Abformung), SLIGA (sacrificial LIGA), bulk micromachining, surface micromachining, micro electrodischarge machining (EDM), laser micromachining, 3-D stereolithography, and other techniques. Bulk micromachining has been utilized for making relatively simple micromechanical structures. Bulk micromachining generally entails cutting or machining a bulk substrate using an appropriate etchant (e.g., using liquid crystal-plane selective etchants; using deep reactive ion etching techniques). Another micromachining technique that allows for the formation of significantly more complex microstructures is surface micromachining. Surface micromachining generally entails depositing alternate layers of structural material and sacrificial material using an appropriate substrate which functions as the foundation for the resulting microstructure. Various patterning operations may be executed on one or more of these layers before the next layer is deposited so as to define the desired microstructure. After the microstructure has been defined in this general manner, the various sacrificial layers are removed by exposing the microstructure and the various sacrificial layers to one or more etchants. This is commonly called xe2x80x9creleasingxe2x80x9d the microstructure from the substrate, typically to allow at least some degree of relative movement between the microstructure and the substrate. Although the etchant may be biased to the sacrificial material, it may have some effect on the structural material over time as well. Therefore, it is generally desirable to reduce the time required to release the microstructure to reduce the potential for damage to its structure.
Microstructures are getting a significant amount of attention in the field of optical switches. Microstructure-based optical switches include one or more mirror microstructures. Access to the sacrificial material that underlies the support layer that defines a given mirror microstructure is commonly realized by forming a plurality of small etch release holes down through the entire thickness or vertical extent of the mirror microstructure (e.g., vertically extending/disposed etch release holes). The presence of these small holes on the upper surface of the mirror microstructure has an obvious detrimental effect on its optical performance capabilities. Another factor that may have an effect on the optical performance capabilities of such a mirror microstructure is its overall flatness, which may be related to the rigidity of the mirror microstructure. xe2x80x9cFlatnessxe2x80x9d may be defined in relation to a radius of curvature of an upper surface of the mirror microstructure. This upper surface may be generally convex or generally concave. Known surface micromachined mirror microstructures have a radius of curvature of no more than about 0.65 meters.
The present invention is a surface micromachined optical system that is fabricated on a substrate that is compatible with surface micromachining. Multiple structural layers may be utilized by this system. In this regard, the system includes a first mirror microstructure that is movably interconnected with the substrate, and that may be moved relative to the substrate by at least one actuator that is interconnected with the mirror microstructure. Any way of interconnecting the mirror microstructure with the substrate that allows the mirror microstructure to move relative to the substrate in the desired/required manner may be utilized by the present invention. Moreover, any type of actuator, any number of actuators, or both may be utilized to accomplish the desired movement of the mirror microstructure relative to the substrate. All aspects of the present invention that will now be discussed in more detail utilize the various features addressed in this paragraph and will not be repeated on each occasion.
A first aspect of the above-described surface micromachined optical system has a first mirror microstructure that includes a first structural layer that is spaced from the substrate, a second structural layer that is spaced from the first structural layer away from the substrate, and a plurality of first columns that extend between and fixedly interconnect the first and second structural layers (i.e., so that the first and second structural layers are joined together), and further that are appropriately spaced. As such, the first structural layer is disposed between the second structural layer and the substrate, or at a lower elevation or level relative to the substrate than the second structural layer. Relative movement is allowed between the first mirror microstructure associated with the first aspect and the substrate.
Various refinements exist of the features noted in relation to the first aspect of the present invention. Further features may also be incorporated in the first aspect of the present invention as well. These refinements and additional features may exist individually or in any combination. The surface micromachined optical system of the first aspect may include other microstructures at the same or different elevations or levels relative to the substrate than that which is occupied by the first and/or second structural layers and/or the plurality of first columns of the first mirror microstructure of the first aspect. One or more microstructures or a part thereof may also be disposed directly under the first mirror microstructure such that the same is located directly between the first structural layer and the substrate. There will still be a space between the first structural layer and any underlying structure of the system to allow for relative movement between the first mirror microstructure and the substrate.
Typically the first and second structural layers associated with the first aspect will be vertically aligned such that the second structural layer will be directly above the first structural layer, and further such that their respective centers will be vertically aligned. There may be circumstances where such will not be the case. Appropriate materials for the first and second structural layers and the plurality of first columns include polysilicon in which case the substrate may be silicon-based. Other materials that are appropriate for surface micromachining operations may be utilized for the first and second structural layers associated with the first aspect, such as various other forms of silicon; poly germanium-silicon; various metal films (e.g., aluminum); various metals (e.g., Al/Ni); and silicon carbide.
The surface micromachined optical system of the first aspect may be used for various applications, including optical switching, optical correction such as adaptive optics, and optical scanning. Materials that are used to define the second structural layer may possess sufficient optical properties for providing the desired/required optical function. However, it may be desirable to apply an optically reflective layer to the upper surface of the second structural layer to achieve desired optical properties/characteristics for the first mirror microstructure. Appropriate materials that may be deposited on the upper surface of the second structural layer include gold, silver, and aluminum for metal coatings. For metals, gold and an associated adhesion layer are preferable to obtain a suitable reflectance.
Other structural layers may be utilized by the first mirror microstructure of the first aspect. For instance, a third structural layer may be spaced from the second structural layer in a manner such that the second structural layer is located between the first and third structural layers, in which case the third structural layer would provide the desired/required optical functionality. Those features addressed above in relation to the optical features/characteristics of the second structural layer could then be utilized by the third structural layer. Structural interconnection of the third structural layer to the second structural layer may be accomplished by a plurality of second columns that extend between the second and third structural layers to fixedly interconnect the same. In one embodiment, none of the columns that structurally interconnect the first and second structural layers are aligned with any of the columns that structurally interconnect the second and third structural layers.
Increasing the number of spaced, but interconnected structural layers as a general rule and in accordance with the first aspect is believed to increase the rigidity or stiffness of the first mirror microstructure. This may be beneficial for optical as well as other applications. Therefore, a three-layered optical mirror microstructure in accordance with the first aspect should be more rigid or stiffer than a two-layered optical mirror microstructure in accordance with the first aspect. Similarly, a two-layered optical mirror microstructure in accordance with the first aspect should be more rigid or stiffer than a single layer or laminated mirror microstructure.
The first mirror microstructure of the first aspect may also have a desired radius of curvature on its uppermost structural layer. In one embodiment, the radius of curvature of a structurally reinforced structural layer in the first mirror microstructure that provides an optical function in accordance with the first aspect is at least about 1 meter, in another embodiment is at least about 2 meters, and in yet another embodiment is about 14 meters.
A second aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, a second structural layer that is spaced from the first structural layer away from the substrate, and a plurality of at least generally laterally extending first ribs or rails that also extend between and structurally interconnect the first and second structural layers so as to fix the first structural layer to the second structural layer. Ribs or rails differ from columns in that the ribs or rails have a length dimension that is greater (and typically significantly greater) than their width dimension, in contrast to the types of columns addressed above in relation to the first aspect which do not. As in the case of the first aspect, the first structural layer is disposed between the second structural layer and the substrate, or at a lower elevation or level relative to the substrate than the second structural layer. Relative movement is also allowed between the first mirror microstructure associated with the second aspect and the substrate.
Various refinements exist of the features noted in relation to the second aspect of the present invention. Further features may also be incorporated in the second aspect of the present invention as well. These refinements and additional features may exist individually or in any combination. The surface micromachined optical system of the second aspect may include other microstructures at the same or different elevations or levels relative to the substrate than that which is occupied by the first and/or second structural layers and/or the plurality of first rails of the first mirror microstructure of the second aspect. One or more microstructures or a part thereof may also be disposed directly under the first mirror microstructure such that the same is located directly between the first structural layer and the substrate. There will still be a space between the first structural layer and any underlying structure of the system to allow for relative movement between the first mirror microstructure and the substrate.
Typically the first and second structural layers associated with the second aspect will be vertically aligned such that the second structural layer will be directly above the first structural layer, and further such that their respective centers will be vertically aligned. There may be circumstances where such will not be the case. Appropriate materials for the first and second structural layers, as well as the plurality of first rails, include polysilicon in which case the substrate may be silicon-based. Other materials that are appropriate for surface micromachining operations may be utilized by the second aspect as well and as noted above in relation to the first aspect.
The surface micromachined optical system of the second aspect may then be used for the type of optical applications addressed above in relation to the first aspect. Materials that are used to define the second structural layer may possess sufficient optical properties/characteristics for providing the desired/required optical function. However, it may be desirable to apply an optically reflective layer to the upper surface of the second structural layer to achieve desired optical properties/characteristics for the first mirror microstructure, including those noted above in relation to the first aspect.
As noted above, the plurality of first rails associated with the second aspect are at least generally laterally extending. xe2x80x9cAt least generally laterally extendingxe2x80x9d herein, and specifically in the context of the second aspect, means that the plurality of first rails extend at least generally parallel with the substrate. Typically this will be such that the first rails will be disposed at a constant, fixed elevation relative to the first substrate, although such may not necessarily be the case (i.e., the elevation of one or more of the first rails relative to the substrate may change progressing along its length). Various layouts of the plurality of first rails may be utilized. For instance, the plurality of first rails may be disposed: 1) in at least substantially parallel relation; 2) in non-intersecting relation; 3) so as to extend at least toward (and thereby including to) a first point (e.g., each of the first rails may terminate at least substantially equidistantly from this first point; one or more of the first rails may extend closer to the first point than at least one other first rail; at least two of the first rails may intersect at the first point; or any combination thereof); 4) such that at least two of the first rails extend at least toward (and thereby including to) a first point, and such that at least two other first rails extend at least toward (and thereby including to) a second point that is spaced from the first point (i.e., not all first rails need to converge toward the same common point); 5) such that at least two of the first rails intersect; and 6) any combination thereof. Yet another embodiment has multiple groups of the first rails that are in different orientations. For instance, one group of the first rails may all extend in a first direction, and another group of the first rails may all extend in a second direction that is different from the first direction, and including being perpendicular to the first direction to define a waffle-like pattern. Stated another way, the structural interconnection between the first and second structural layers may be in the form of a grid or the like, and the first rails associated with the second aspect may be considered as a part thereof.
Multiple configurations may define the length dimension of the first rails or how the extend within the lateral dimension. For instance, the first rails may be axially or linearly extending in the lateral dimension (i.e., the first rails may extend laterally in axial or linear fashion). The first rails may also extend in non-linear fashion in the lateral dimension as well. One example is where the first rails meander in the lateral dimension, such as sinusoidally or in a xe2x80x9czig-zagxe2x80x9d fashion within a plane that is at least generally parallel relation with the substrate.
Other structural layers may be utilized by the first mirror microstructure of the second aspect. For instance, a third structural layer may be spaced from the second structural layer in a manner such that the second structural layer is located between the first and third structural layers, in which case the third structural layer would provide the desired/required optical functionality. Those features addressed above in relation to the optical features/characteristics of the second structural layer could then be utilized by the third structural layer. Structural interconnection of the third structural layer to the second structural layer may be accomplished by a plurality of at least generally laterally extending second ribs or rails that extend between and structurally interconnect the second and third structural layers so as to fix the third structural layer to the second structural layer. The various characteristics/features discussed above in relation to the plurality of first rails are equally applicable to the plurality of second rails. In one embodiment, the plurality of first rails are disposed in a first orientation in the lateral dimension and the plurality of second rails are disposed in a second, different orientation in the lateral dimension. These first and second orientations may be such that the plurality of first rails are disposed in an at least substantially perpendicular orientation to the plurality of second rails.
Increasing the number of spaced, but interconnected layers as a general rule and in accordance with the second aspect is believed to increase the rigidity or stiffness of the first mirror microstructure, which is beneficial in optical applications. Therefore, a three-layered optical mirror microstructure in accordance with the second aspect should be more rigid or stiffer than a two-layered optical mirror microstructure in accordance with the second aspect. Similarly, a two-layered optical mirror microstructure in accordance with the second aspect should be more rigid or stiffer than a single layer or laminated mirror microstructure.
The microstructure of the second aspect may also have a desired radius of curvature on its uppermost structural layer. In one embodiment, the radius of curvature of a structurally reinforced structural layer in the first mirror microstructure in accordance with the second aspect is at least about 1 meter, in another embodiment is at least about 2 meters, and in yet another embodiment is about 14 meters.
A third aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, a second structural layer that is spaced from the first structural layer away from the substrate, and at least one structural interconnection that extends between and fixedly interconnects the first and second structural layers. An upper surface of the second structural layer has a radius of curvature that is at least about 1 meter, and more typically at least about 2 meters. Therefore, the upper surface of the second structural layer is substantially flat which makes the first mirror microstructure of this third aspect particularly beneficial for various optical applications. The various features discussed above in relation to the first and second aspects may be utilized by this third aspect of the present invention as well, alone or in any combination.
A fourth aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, and at least one structurally reinforcing member that extends from the first structural layer toward, but not to, the substrate. Each such structural reinforcement member may fixedly attach to an underlying structural layer, although such need not be the case (i.e., the structural reinforcement member(s) of the fourth aspect may be cantilever, or may be of the form of the first mirror microstructures noted above in relation to the first or second aspects). The first structural layer has an upper surface with a radius of curvature that is at least about 1 meter, and more typically at least about 2 meters. Therefore, the upper surface of the first structural layer is substantially flat which makes the first mirror microstructure of this fourth aspect particularly beneficial for use in various optical applications. The various features discussed above in relation to the first and second aspects may be utilized by this fourth aspect of the present invention as well, alone or in any combination.
A fifth aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, a second structural layer that is spaced from the first structural layer away from the substrate, and at least one structural interconnection that extends between and fixedly interconnects the first and second structural layers. A first structural interconnection that fixes the first structural layer to the second structural layer is positioned to provide a reinforcement ratio of no more than about 0.5. This reinforcement ratio is a ratio of a first distance to a second distance. The first distance is a distance from a center of the second structural layer in the lateral dimension to a portion of the first structural interconnection that is disposed closest to the center of the second structural layer. The second distance is the diameter of the second structural layer. Therefore, the second structural layer is structurally reinforced at least close to (and thereby including at) its center.
A sixth aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, and at least one structural reinforcing member that extends from the first structural layer toward, but not to, the substrate. Each structural reinforcement member may fixedly attached to an underlying structural layer, although such need not be the case (i.e., the structural reinforcement member(s) of the sixth aspect may be cantilever, or may be of the form of the structures noted above in relation to the first or second aspects). A first structural reinforcement member that extends down from the first structural layer is positioned to provide a reinforcement ratio of no more than about 0.5. This reinforcement ratio is a ratio of a first distance to a second distance. The first distance is a distance from a center of the second structural layer in the lateral dimension to a portion of the first structural reinforcement member that is disposed closest to the center of the second structural layer. The second distance is the diameter of the second structural layer. Therefore, the second structural layer is structurally reinforced at least close to (and thereby including at) its center.
A seventh aspect of the above-described surface micromachined optical system has a mirror microstructure that includes a first structural layer that is spaced from the substrate, a second structural layer that is spaced from the first structural layer away from the substrate, at least one structural interconnection that extends between and fixedly interconnects the first and second structural layers, a third structural layer that is spaced from the second structural layer away from the second structural layer, and at least one structural interconnection that extends between and fixedly interconnects the second and third structural layers. The various features discussed above in relation to the first and second aspects may be used by this seventh aspect as well, alone or in any combination, including using the various reinforcing structures noted above for the structural interconnections between the first and second structural layers, and between the second and third structural layers.

Surface micromachined optical system with reinforced mirror microstructure


To improve a capacity of coherent detection of the spread spectrum (SS) signal, when interference and noise can not be neglected. Amplitude phase estimation unit outputs transmission line estimation value including fluctuations in the transmission lines, using known pilot signals of which transmission sequences are known. The pilot signal is extracted from the despread signal through despreading filter. Reliability measurement unit pursues a reliability value of transmission line estimation value. Interpolation unit generates vectors for compensating the phase, by deciding a method of interpolation on the basis of the reliability. Coherent detection unit compensates the amplitude and phase of information symbol to execute the coherent detection.

1. Technical Field of the Invention
The present invention relates to a decoding circuit for receivers in mobile communication systems using code division multiple access (CDMA).
2. Description of the Prior Art
Conventional transmitters for spread spectrum (SS) communication under the CDMA modulate communication data are modulated beforehand by modulation techniques. In other words, the modulated communication data are further modulated by Pseudo Noise (PN) sequence for SS modulation in order to widen the transmission bandwidth. The widened transmission bandwidth is used for a plurality of channels, wherein different PN sequences are assigned for every user or every kind of information.
Therefore, receivers firstly despread the wide-band SS signal into its original bandwidth and then decodes the despread signal by using conventional techniques. Here, a correlation of PN sequence is detected between the received signal and the receiver side by despread filter such as a matched filter which handles the PN sequence as tap coefficients, or a adaptive filter which optimizes the despreading process by varying the tap coefficients.
The receiving side can pick up a communication signal among multiplexed communication signals by detecting the correlation. The picked-up signal is a complete auto-correlation of the desired signal, when the PN sequence of the receiving side has no cross-correlation with other PN sequences. However, in general, PN sequences have cross-correlation with each other. Therefore, the output from the despread filter contains interference signals which are not desired by the receiving side. The above-mentioned interference signals increase with the number of communication channels and degrade quality of received signal which is further degraded by thermal noise in the receiver and noises in transmission lines.
In the CDMA transmission, wherein information signal is spread by PN signal of which speed is higher than that of the information signal, prescribed pilot signals are inserted periodically in between the information signals, as shown in FIG. 8. Therefore, phase vectors of the information symbols are obtained by an interpolation on the basis of phase vectors of the pilot symbols, as shown in FIG. 9. Here, phase vector 1001 shows a track of end point of every symbol due to fluctuations in the transmission lines. Phase vector 1002 is a phase vector of every information symbol obtained by the interpolation. Phase vector 1003 is a phase vector which is an average phase vector in pilot symbol periods.
A decode circuit implementing the above-mentioned method is shown in FIG. 10. The decode circuit as shown in FIG. 10 comprises matched filter 803 which operates under chip cycle Tc with a tap length of 1 symbol, interpolation detection unit 807, and Decision unit 109.
The decode circuit as shown in FIG. 10 despreads SS signal 101, executes coherent detection, and outputs identified signal 102 on the basis of coherent detection.
Matched filter 803 comprises a plurality of delay units 804, a plurality of tap coefficient multipliers 805, and tap signal adder 806. Further, interpolation synchronous detector 807 for compensating a phase difference from matched filter 803 comprises amplitude phase estimation unit 105, first order interpolation unit 809, and coherent detection unit 108.
Amplitude phase estimation unit 105 pursues transmission estimation value 301 concerning the amplitude and phase in the transmission line, on the basis of a received phase of the pilot signal contained in the despread signal from matched filter 806.
First order interpolation unit 809 interpolates a received phase vector, inspecting a location of each information symbol.
Coherent detection unit 108 executes coherent detection, by compensating errors in the amplitude and phase of the information symbol on the basis of the received phase vector which is obtained by first order interpolation unit 809.
Decision unit 109 identifies a phase of the output from interpolation coherent detection unit 807. The output from Decision unit 109 is identified signal 102.
SS signal 101 as shown in FIG. 10 which contains known pilot symbol is inputted into matched filter 803 which has xe2x80x9cMxe2x80x9d taps extracted every chip cycle Tc. Here, an integer xe2x80x9cMxe2x80x9d is a spread factor. Signal vectors of each tap inputted into matched filter 803 are multiplied by tap coefficient vectors of which coefficient is determined by PN sequence. The tap coeflicient vector is CM, CMxe2x88x921, . . . , C2, Cl, as shown in FIG. 10. Then, the signals from each tap are added in tap signal adder 806 and outputted as a despread signal. Then, amplitude phase estimation unit 105 in interpolation coherent detection unit 807 pursues, by using the known pilot symbol, a received phase vector which represents errors of amplitude and phase due to the fluctuation of transmission lines. First order interpolation unit 809 interpolates a received phase vector, inspecting a location of each information symbol. Coherent detection unit 108 executes coherent detection, by compensating errors in the amplitude and phase of the information symbol on the basis of the received phase vector which is obtained by first order interpolation unit 809. Decision unit 109 identifies a phase of the output from interpolation coherent detection unit 807. The output from Decision unit 109 is identified signal 102.
The conventional decode circuit as shown in FIG. 10 compensates fading distortion by using the pilot signal.
However, when received SS signal contains the interference and noise which can not be neglected, the pilot signal is also distorted. Therefore, the coherent detection is not correctly executed, because the transmission lines can not be estimated correctly.
Therefore, the conventional decode circuit has a disadvantage that the coherent detection is not correctly executed, when the interference and noise can not be neglected.
Therefore, an object of the present invention is to provide a decode circuit with improved capability of coherent detection such that transmission lines are estimated correctly, even when the received SS signal contains much interference and noise.
A decode circuit of the present invention comprises a despreading filter for despreading spread spectrum (SS) signal, an amplitude phase estimation unit which estimates the amplitude and phase in transmission lines on the basis of pilot signals included in the despread signal, a reliability measurement unit for calculating a reliability value of the estimated amplitude and phase in the transmission lines, an interpolation unit for compensating the phase of information symbols by deciding a method of interpolation on the basis of the reliability, a coherent detection unit which detects the despread signal by using the interpolated estimation value in the transmission lines, and an decision unit for identifying the output from the coherent detection unit on the basis of its phase.
In short, the decode circuit of the present invention measures the reliability of the transmission line estimation value. Further, an interpolation method is decided on the basis of the reliability. Then, compensation vectors for compensating the phase are generated by the decided interpolation method to execute the coherent detection.
Therefore, the coherent detection is executed exactly, even when the interference and noise cannot be neglected.
Here, the reliability measurement unit may also calculate a reliability value of the detected signal outputted from the coherent detection unit.
According to the decode circuit of the coherent detection of the spread spectrum (SS) signal is optimized, even when the interference and noise can not be neglected.

Decode circuit for code division multiple access receiver