A receiving antenna for digital television signal reception includes a dielectric substrate, a radiating plate formed on the dielectric substrate with a bar shape, having a first long edge and a second long edge corresponding to the first long edge, a slit formed on the radiating plate with a length at least two times the width of the radiating plate, having a terminal at about the center of the first long edge and a terminal at the second long edge, and separating the radiating plate into a first sub-plate and a second sub-plate, a first feeding point formed on the first sub-plate, a second feeding point formed on the second sub-plate, and a feeding coaxial cable having a core conductor connected to the first feeding point and a grounding conductor connected to the second feeding point.

1. Field of the Invention
The present invention relates to a digital-television receiving antenna, and more particularly, to a broadband planar digital-television receiving antenna.
2. Description of the Prior Art
In the past, a TV program operator broadcasts analog signals to receivers through ultra-high-frequency (UHF) or very-high-frequency (VHF) channels. Analog signals are easily interfered during transmission, so that picture clarity, noise and ghost-image reductions are insufficient. Also, transmitting analog signals requires a considerable frequency bandwidth, which decreases the efficiency of frequency utilization. In contrary, a digital TV (DTV) system transmits TV programs with digital signals, which can be compressed to increase the efficiency of frequency utilization. Moreover, a receiver of the DTV system can process debugging or error corrections for digital signals, so that the DTV system has higher quality in video and audio, and more channel numbers. Now, the DTV system has been developed in three main standards, DVB (Digital Video Broadcasting) by European Broadcast Union (EBU), ATSC (Advanced Television Systems Committee) by US, and ISDB (Integrated Services Digital Broadcasting) by Japan. The DVB standard has been authorized by European Telecommunications Standard Institute (ETSI), and includes substandards of DVB-S (satellite), DVB-C (cable) and DVB-T (terrestrial). According to the DVB standard, a DVB system encodes video and audio signals with MPEG-2 coding technology, modulates the signals with coded orthogonal frequency division multiplexing (COFDM), and uses a frequency bandwidth of 8 MHz (23.5 Mbps). A DVB-T system can establish a single frequency network (SFN) for increasing available frequency resources, provide interactive TV functions, and reduce a multipath effect. In order to improve mobile receiving efficiency of a vehicle DVB-T receiver, advanced channel estimation is applied and a dual-antenna is used for receiving radio waves and performing diversity combining, and accordingly, circuit complexity, hardware cost, and power consumption cannot be decreased. A DTV receiving antennal is a fundamental equipment of a common DTV tuner. Most DTV receiving antennas are monopole antennas, which have large sizes and insufficient bandwidths. Therefore, a planar DTV receiving antenna having a wide bandwidth is desired.
TW patent No. 521,455 discloses a small planar DTV antenna for receiving DTV signals. However, the antenna of TW patent No. 521,455 has a large volume, so that it is inconvenient.
Referring to FIG. 2, which illustrates a schematic diagram of an antenna 2 of the prior art. The antenna 2 includes a dielectric substrate 20, a radiating plate 21, a slit 24, feeding points 25, 26, and a feeding coaxial cable 27. The dielectric substrates 20 can be a copper clad laminate substrate, or be made of film or rubber. The radiating plate 21 is formed on the dielectric substrates 20 by printing or etching. The radiating plate 21 is formed as a bar shape, and includes a first long edge 211 and a second long edge 212 corresponding to the first long edge 211. A length of the slit 24 is approximately equal to a width W of the radiating plate 21. The slit includes terminals 241 and 242. The terminal 241 is at about a center of the first long edge 211, and the terminal 142 is also at about the center of the second long edge 212. The slit 24 separates the radiating plate 21 into a first sub-plate 22 and a second sub-plate 23. The feeding points 25 and 26 are near the first long edge 211, and at the first sub-plate 22 and the second sub-plate 23, respectively. The feeding coaxial cable 27 is utilized for transmitting/receiving signals, and includes a core conductor 271 connected to the feeding point 25 and a grounding conductor 272 connected to the feeding point 26. Note that, the slit 24 is formed without any bending, or is perpendicular to the first long edge 211 and the second long edge 212.
Referring to FIG. 3, which illustrates a schematic diagram of an antenna 3 of the prior art. The antenna 3 includes a dielectric substrate 30, a radiating plate 31, a slit 34, feeding points 35, 36, and a feeding coaxial cable 37. The dielectric substrates 30 can be a copper clad laminate substrate, or be made of film or rubber. The radiating plate 31 is formed on the dielectric substrates 30 by printing or etching. The radiating plate 31 is formed as a bar shape, and includes a first long edge 311 and a second long edge 312 corresponding to the first long edge 311. The length of the slit 34 is approximately equal to the width W of the radiating plate 31. The slit includes terminals 341 and 342. The terminals 341 and 342 are at a distance (about 60 mm) from centers of the first long edge 311 and the second long edge 312. The slit 34 separates the radiating plate 31 into a first sub-plate 32 and a second sub-plate 33. The feeding points 35 and 36 are near the first long edge 311, and at the first sub-plate 32 and the second sub-plate 33, respectively. The feeding coaxial cable 37 is utilized for transmitting/receiving signals, and includes a core conductor 371 connected to the feeding point 35 and a grounding conductor 372 connected to the feeding point 36. Note that, the slit 34 is formed without any bending, or is perpendicular to the first long edge 311 and the second long edge 312.


There is provided a motif-specific, context-independent antibody that specifically binds a recurring, modified motif consisting of (i) at least one sumoylated lysine residue, and (ii) one or more degenerate amino acids bound by a peptide bond to said sumoylated lysine residue, said antibody specifically binding said motif in a plurality of non-homologous peptides or proteins within an organism in which it recurs. Also provided is a motif-specific, context-independent antibody that specifically binds a recurring, modified motif consisting of (i) a C-terminal aspartic acid residue, and (ii) one or more degenerate amino acids bound by a peptide bond to said C-terminal aspartic acid residue, said antibody specifically binding said motif in a plurality of non-homologous peptides or proteins within an organism in which it recurs.

Motif-specific, context-independent antibodies are useful in characterizing various forms of cellular regulation as well as serving to profile genome wide changes in cellular protein levels and protein modification. Identifying the targets of intracellular signaling cascades is of major importance in understanding cell growth, differentiation, and cell death. Protein kinase cascades relay information from the cell surface to multiple cellular compartments including the nucleus and more distant cell processes such as synapses (Karin et al., Curr. Opin. Cell. Biol. 6:415-424 (1994)).
Although a few targets of protein phosphorylation have been identified, most remain unknown, particularly those that regulate cell growth and differentiation. For example, the MAP kinase cascade is known to play an important role in the regulation of cell growth (Lewis et al., Adv. Cancer Res. 74:49-139 (1998), Crowley et al., Cell 77:841-852 (1994)). However, beyond a handful of substrates, few protein targets responsible for the diverse actions of the MAP kinase cascade have been identified (Fukunaga and Hunter, EMBO 16(8):1921-1933 (1997), Stukenberg et al., Curr. Biol. 7:338-348 (1997)).
Another example of cell signaling proteins are the 14-3-3 proteins, which represent a phylogenetically conserved family of phosphoserine binding proteins whose precise role in cell signaling has yet to be determined (Burbelo and Hall, Curr. Biol. 5(2):95-96 (1995)). These proteins represent a large fraction of total brain protein and are known to bind a wide variety of signaling molecules including: ras, raf, bad, cdc25, and many others (Yaffe et al., Cell 91:961-971 (1997)). Recently, it has been shown that 14-3-3 proteins bind specifically to phosphorylated sites on proteins with the following motif: RXRSXS*XP (SEQ ID NO: 146) where S* is phosphoserine and X represents any amino acid (Muslin et al., Cell 84:889-897 (1996), Yaffe et al. supra (1997)).
Similarly, histones have long been known to be modified by acetylation at specific lysine residues. Acetylation of lysine in histones is thought to reduce protein-DNA interactions and serve to open chromatin in regions undergoing transcription (Struhl, Genes & Development, 12:599-606 (1998)). Recently, other proteins associated with transcription complexes have been shown to be acetylated on lysine although the functional significance is unclear (Imhof et al., Curr. Biol. 7:689-692 (1997), Struhl supra (1998)).
Antibodies against phosphotyrosine have proven to be of great value in identifying and characterizing intracellular signaling mechanisms (Ross et al., Nature 294:654 (1981), Kozma et al., Method. Enzymol. 201:28 (1991), White and Backer, Method. Enzymol. 201:65 (1991), Kamps, Method. Enzymol. 201:101 (1991)). Their value derives from two properties; 1) their ability to discriminate whether or not a protein is tyrosine phosphorylated, and 2) their ability to react with a large variety of different proteins. These properties have proven invaluable in tracing intracellular signaling pathways and identifying new targets of activated tyrosine kinases.
Ideally, the most useful phosphotyrosine antibodies should be as general as possible, that is they should recognize phosphotyrosine independently of the protein sequences in which it is embedded (context independent) so as to allow detection of all possible phosphotyrosine residues. The most successful approaches for producing phosphotyrosine antibodies have utilized phosphotyrosine or phosphotyramine coupled via their free amino groups to keyhole limpet hemocyanin using hetero- or bifunctional crosslinking agents (Frackelton et al., Method. Enzymol. 201:79 (1991), White and Backer supra (1991), Wang, Method. Enzymol. 201:53 (1991), Kamps supra (1991)). Although currently produced polyclonal and monoclonal phosphotyrosine antibodies do recognize many different proteins, they often show crossreactivity with other phosphate containing compounds, for example, mononucleotides (Frackelton et al. supra (1991), Kamps supra (1991)). More importantly, most phosphotyrosine antibodies raised in this fashion display variable sequence reactivity, depending not only on the phosphorylated amino acid, but also upon the amino acid sequences surrounding phosphotyrosine. For example, the present inventors have observed that most phosphotyrosine antibodies do not recognize phosphotyrosine preceded by proline as found in the activation loop of JNK and hence do not react significantly with activated (tyrosine phosphorylated) JNK [(Tan et al. unpublished observations)]. The reason for the variable reactivity is likely due to the fact that the phosphotyrosine antigen is not presented directly to the immune system in the context of variable surrounding amino acids, but is instead presented as a hapten, inappropriately coupled to the KLH carrier via artificial linkages. This approach tends to produce antibodies that react well with phosphotyrosine but are sometimes blocked by surrounding amino acids as they are not present in the antigen.
Other approaches have utilized total cellular phosphotyrosine containing proteins as immungens (Glenney, Method. Enzymol. 201:92 (1991), Wang supra (1991)) with considerable success but the context-dependence of the resulting antibody specificities was not carefully determined, although antibodies raised in this fashion did react with a majority of tyrosine phosphorylated proteins. Estimates as to the fraction of tyrosine phosphorylated proteins detected range from 50% to 94% (Kamps supra (1991)).
Attempts to use the above mentioned techniques to produce similar antibodies for phosphoserine and phosphothreonine have met with limited success. Antibodies produced to date have limited crossreactivity and lower affinity for phosphoserine or phosphothreonine probably due to the poor immunogenicity of these phospho-amino acids compared to phosphotyrosine (Heffetz et al., Method. Enzymol. 201:44 (1991)). Context-dependence and low affinity have limited the utility of currently available phosphoserine and phosphothreonine antibodies, especially when compared to phosphotyrosine antibodies.
Site-specific phosphoserine and phosphothreonine antibodies were first described by Nairn et al. in 1982 and have proven to be highly useful tools to study protein phosphorylation (Czernik et al., Method. Enzymol. 201:264 (1991), Czernik et al., Neuroprot. 6:56-61 (1995)). One drawback of this type of antibody is that a different antibody needs to be produced for each site of interest. Clearly, development of antibodies that detect phosphoserine or phosphothreonine in a substantially context-independent fashion would be desirable for use in tracing serine/threonine kinase cascades and in defining their biological responses. Likewise, development of context-independent phosphotyrosine antibodies would overcome the limitations of currently available antibodies.
Motif-specific, context-independent antibodies would also be useful in identifying new targets of 14-3-3 action (i.e., other proteins phosphorylated at this motif) and in characterizing the protein kinases that phosphorylate these sites. Likewise antibodies reactive against acetylated lysine would serve as useful tools to study the functional significance of acetylation of histones.
Such antibodies can further be used as general reagents for detecting phosphorylation or other enzymatic modification in vitro, such as in high throughput kinase assays for drug screens, as a single antibody can be used to recognize many different phosphorylated substrates. Phosphotyrosine antibodies are currently employed in high throughput kinase assays to screen for selective, high affinity tyrosine kinase inhibitors. Compounds or drugs that block enzyme activity are detected by their ability to inhibit kinase activity as determined by a reduction of phosphotyrosine antibody binding to phosphorylated substrate. Similar assays can be set up to screen for pharmaceutically useful compounds using antibodies produced as described above for phosphoserine, phosphothreonine, or antibodies detecting other protein modifications.
Antibodies that detect short recurring motifs in a context-independent fashion will also be particularly useful in profiling genome wide changes in protein levels and protein modification. For example, the use of context-independent phosphothreonine antibodies and 2D gel electrophoresis to profile genome wide changes in protein phosphorylation (Patterson and Garrels, Cell Biology: A Laboratory Handbook 249-257 (1994), Academic Press) as the result of drug treatment or overexpression of a particular protein will undoubtedly prove useful in identifying potential drug-protein interactions and suggest new downstream targets for overexpressed proteins.

Motif-specific and context-independent antibodies that specifically bind to a cleaved caspase motif


A duplex expansion apparatus for expanding a wellbore tubular to two different diameters from an initial diameter is provided. The duplex expansion apparatus includes: a first diameter expansion cone that is, in a relaxed state, of a diameter less than the internal diameter and in an expanded state of a diameter greater than the internal diameter; a second diameter expansion cone that is, in a relaxed state, of a diameter less than the internal diameter and in an expanded state of a diameter greater than the diameter of the first diameter expansion cone in the expanded state; and an assembly mandrel that is capable of transferring both the first diameter expansion cone and the second diameter expansion cone into their expanded states.

Radial expansion of tubular elements has been applied, for example, in wellbores whereby a tubular casing is lowered into the wellbore in unexpanded state through one or more previously installed casings. After the casing is set at the required depth, an expander is moved through the casing to radially expand the casing to an inner diameter which is about equal to the inner diameter of the previously installed casing. In this manner it is achieved that the inner diameters of subsequent casings are about equal as opposed to conventional casing schemes which have stepwise decreasing casing diameters in downward direction. For example, WO-A-93/25800 teaches expansion of a casing in a wellbore by a solid expansion mandrel, the mandrel being pulled through the tubular or hydraulically pushed through the casing.
Expansion of tubulars is discussed in, for example, U.S. Pat. No. 6,557,640, and published U.S. patent application Ser. No. 10/382,325, the disclosures of which are incorporated herein by reference.
Expandable expansion cones are suggested, for example, in U.S. Pat. No. 6,460,615 the disclosure of which is incorporated herein by reference. Expansion of a cone within a casing requires that the casing be expanded as the expansion cone is expanded. This requires considerably more force than the force needed to pull a mandrel through the casing once the cone has been expanded. Further, if the lower casing is to overlap the previously installed casing and the inside diameter of the final casing is to remain constant through the overlap section, then the overlap section of the upper casing needs to be expanded by more than the remainder of the casing. Some provision for this greater expansion also needs to be provided.

Expander for expanding a tubular element


The present invention relates to methylol modified bismaleimides which are prepared by reacting under condensation conditions an aldehyde and a bismaleimide compound wherein the aldehyde is selected from the group consisting of formaldehyde, acetaldehyde or mixtures thereof; and. said bismaleimide compound is of the formula: ##STR1## wherein R is a divalent radical selected from the group consisting of an acyclic aliphatic group, a cyclic aliphatic group, an aromatic group, and one to three alkylaromatic groups and wherein these groups may contain a hetero atom selected from O, N and S.

Various bismaleimides, such as N,N'-(m-phenylene)bismaleimide, have been added to rubber to modity its properties. For example, in U.S. Pat. No. 4,803,250 various bismaleimides are added to rubber in combination with sulfur and accelerators to improve the resistance to reversion in the vulcanization step. Whereas, bismaleimides can be used to improve reversion resistance, the present inventors have discovered that a new and useful modified form of such bismaleimides are superior in improving the tear resistance of rubber. Since many rubber products are subjected to a harsh environment in use, any improvement in the tear resistance of such rubbers further contributes to the longevity and structural integrity of products made therefrom, including tire treads.

Methylol modified bismaleimides for rubber composition


A method for mounting connection pins in respective through-holes. Each pin having an anchoring part for insertion into said through-hole, a contact part to extend outside said through-hole and having a contact end for contact with the surface of another module of the electronic assembly, and a flange part to abut against said component carrier and located between said anchoring part and said contact part. A die tool has several similar recesses all adapted to receive a contact end of the contact part of a connection pin. The anchoring part of the pin is inserted in a through-hole of the component carrier, and the pin is anchored in the component carrier by exerting a force on a free end of the anchoring part of the pin while an end surface of the contact end abuts the bottom surface of similar recesses in the die tool.

In the electronics industry, connection pins are widely used to provide connection between different parts of an electronic assembly. The connection pins are e.g. mounted in a through-hole in a component carrier or they are surface mounted to a component carrier, which component carrier can have different applications and/or combinations thereof, such as: the component carrier can be part of a printed circuit board, it can carry electronic components and form a component board, it can carry modules such as power modules or stackable modules comprising different components, it can be part of a motherboard etc., all of which can form, or be parts or modules of an electronic assembly. The connection pins usually provide both mechanical connection between the parts of the assembly, as well as electrical connection. There exists a number of known assembly techniques for anchoring a connection pin in or to a component carrier, such as wave soldering, surface mounted pin in solder paste, press-fit, rivet/clinching, etc. The chosen technique mostly depends on the application in which the component carrier is used and the requirements involved.
When using a press-fit assembly technique, the component carrier is provided with a through-hole into which an end portion of the connection pin is to be inserted. The through-hole is slightly narrower than the end portion of the connection pin, and the connection pin has to be inserted into the through-hole by force, thereby achieving a press-fit of the connection pin in the through-hole. The interior wall of the through-hole and/or the press-fit portion of the connection pin are subject to deformation. The connection pin may have a press-fit portion that has a special design in order to facilitate deformation. Examples of such connection pins adapted for press-fit are found in WO 2007/008264 and US 2009/0298312.
According to another known assembly technique, the connection pin has an end portion adapted to be inserted in a through-hole in a component carrier, which end portion is slightly narrower than the size of the through-hole. The connection between the connection pin in the through-hole and the component carrier is achieved by dispensing solder paste in the through-hole, or at the opening of the through-hole, and soldering the connection pin to the component carrier.
According to another known assembly technique, the connection pin may be designed as a rivet and will then be anchored to the component carrier by riveting to the component carrier. In order to provide electrical connection between the component carrier and the connection pin, the connection pin is usually also soldered to the component carrier.
In many applications, each connection pin is anchored to a component carrier via one of its ends, and the other end of the connection pin is intended to be mounted on the surface of another module in the electronic assembly, such as another component carrier, a printed circuit board (PCB), a motherboard, a component board, etc. Whenever such surface mounting is used, one important factor is the tolerances between the different parts. For example, the tolerance related to the distance between the end of each pin facing the surface on which it is to be mounted and the surface itself, is crucial if successful mounting is to be achieved. Since the surface of the module on which the component carrier with its pins is to be mounted generally has a high degree of planarity or flatness, the corresponding end surfaces of the connection pins must also represent a common surface with a high degree of planarity/flatness, or in other words, a high degree of co-planarity of the end surfaces. However, this can be a problem, often due to the fact that the anchoring of the pins in the through-hole of the component carrier nearly always involves some sort of deformation of the pin or the through-hole and/or the component carrier. Also the assembly technique of soldering the pin in a through-hole can result in lack of sufficient co-planarity. Other reasons for irregularities in the planarity of the component carrier can be irregularities that existed already in the original component carrier as such, or in the case of the component carrier being a PCB there may be irregularities that occurred during printing of the circuit pattern. A typical failure in electronic assemblies as described above occurs when the lack of co-planarity of the connection pins of a mounted device, such as a component carrier, impedes the soldering of an intended mating surface which will result in an air gap and lack of electrical connection between the pin with its device and the mating surface.

Method for mounting connection pins in a component carrier, a die tool for mounting connection pins, a component carrier forming a module for an electronic assembly, and such an assembly


The present invention has for an object compounds of formula (I) and colorants containing these 4-aminobiphenyl-3-ol derivatives of general formula (I) for dyeing keratin fibers, particularly hair,

The present invention has for an object colorants for oxidative dyeing of keratin fibers, particularly human hair, containing 4-aminobiphenyl-3-ol derivatives.
In the area of keratin fiber dyeing, particularly hair dyeing, oxidation dyes have attained substantial importance. In this case, the coloration is produced by reaction of certain developers with certain couplers in the presence of an appropriate oxidant. Suitable developers are, in particular, 2,5-diaminotoluene, 2,5-diaminophenylethyl alcohol, p-aminophenol, 1,4-diaminobenzene and 4,5-diamino-1-(2-hydroxyethyl)pyrazole, and suitable couplers are, for example, resorcinol, 2-methyl-resorcinol, 1-naphthol, 3-aminophenol, m-phenylenediamine, 2-amino-4-(2′-hydroxyethyl)amino-anisole, 1,3-diamino-4-(2′-hydroxyethoxy)benzene and 2,4-diamino-5-fluorotoluene.
The oxidation dyes used for dyeing human hair must meet numerous requirements in addition to producing hair colorations that are stable for at least 4 to 6 weeks. For example, these dyes must be harmless from a toxicological and dermatological standpoint, and the hair colorations obtained must have good light fastness, resistance to permanent waving, rubbing fastness and resistance to shampooing as well as sufficient resistance to perspiration. Moreover, by combining appropriate developers and couplers, it must be possible to create a wide range of different color shades.
The adjustment of lighter color shades presents a special problem in terms of uniform dye uptake from the hair roots to the hair tips and in terms of resistance of the colorations to permanent wave treatment. The use of direct yellow-dyeing aromatic nitro dyes together with oxidative hair dye precursors represents a partial solution of the said problem, but the stability of the colorations over a period of several weeks is often unsatisfactory.

Agents for dyeing keratin fibers, containing 4-aminobiphenyl-3-ol-derivatives

Abstract: whereinR1 and R2 independently of each other denote hydrogen, a halogen atom, a cyano group, a hydroxyl group, a C1–C4-alkoxy group, a C2–C4-hydroxyalkoxy group, a C1–C6-alkyl group, a nitro group, a trifluoromethyl group, a —C(O)H group, a —C(O)CH3 group, a —C(O)CF3 group, an —Si(CH3)3 group or a C1–6-hydroxyalkyl group or R1 and R2 together form an —O—CH2—O— bridge.


A light exposure tool of the present invention is so structured as to enable the correction of a linear intrafield error of a shot and of a higher-order intrafield error of the shot depending upon an interfield of a wafer. The light exposure tool comprises a reticle having a written circuit pattern, a reticle stage having the reticle placed on it, a reticle XY stage drive controller, a reticle stage position measuring mechanism, a wafer stage having a semiconductor wafer placed on it, the semiconductor wafer having a plurality of alignment marks formed on it for position identification, a wafer XY stage drive controller, a wafer stage position measuring mechanism, a projection optical mechanism for projecting the circuit pattern of the reticle onto the wafer to create a shot, an alignment mechanism for detecting positions of the alignment marks 9 and setting the reticle and wafer in a desired position, a calculation device, a shot rotation adjusting controller, and an isotropic magnification controller. At a time of light exposures by the projection optical mechanism on the wafer, a per-exposure systematic error of at least one of a rotation error, magnification error and skew error is approximated with an n-th order function Ls (x, y) in an interfield coordinate (x, y) of the wafer to control the alignment mechanism in accordance with the function Ls (x, y) and to correct the per-exposure systematic error depending upon the interfield coordinate of the wafer.

The present invention relates to an exposure tool and method for use in a process for manufacturing a semiconductor device, such as an LSI, and, in particular, to a technique for improving the overlay accuracy of a pattern projected by an optical type stepper and scanner.
Recently, with a microminiaturization of a circuit pattern of an LSI (large scale integrated circuit), an optical stepper of a high resolution type has been widely used as a pattern transfer means. When a device pattern is written on a wafer with the use of this exposure tool, it is necessary to highly accurately align a semiconductor wafer prior to being exposed with light. Upon alignment, a mark position is normally detected on a wafer. The method for detecting the position of the wafer mark is largely classified into a die-by-die system and global alignment system. The die-by-die system detects a mark position on a wafer at each chip for alignment and can achieve high overlay accuracy. The global alignment system, on the other hand, detects several alignment marks on a wafer with an alignment optical system and exposes the wafer with light by correcting a chip array from those detected mark positions. The die-by-die system can achieve high overlay accuracy, but is poor in productivity. This is the reason why the global alignment system is increasingly used.
FIG. 1 diagrammatically shows an arrangement mechanism in the conventional stepper and an alignment signal detecting system. FIG. 2 shows one practical array form of alignment marks 9 initially formed on a semiconductor wafer 4 in FIG. 1. In FIG. 1, a wafer 4 is placed on a wafer stage 5 and the wafer stage 5 can be translated by a wafer stage drive controller, not shown, in an xy direction to the wafer stage 5. A reticle having a light exposure area with a circuit pattern written thereon by an electronic beam is placed on a reticle stage 10 and the reticle stage 10 is translated by a reticle stage drive controller, not shown, in an xy direction to the reticle stage.
The alignment mechanism 1 is arranged near a projection lens 2 and illuminates the alignment marks 9 on the wafer 4, by alignment light, such as an HeNe laser 3, from an alignment light illuminating section, not shown, and allows the alignment light which is reflected/diffracted on the alignment marks 9 to be converted by a light receiving mechanism, not shown, to an electric signal and then by an alignment signal processing circuit (not shown) to position information (alignment output signal). A wafer stage laser interferometer 7 illuminates, with laser light, a mirror 7a mounted on the wafer stage 5 and measures the position of the wafer stage 5 by detecting the laser beam reflected on the mirror. A calculation device 8 calculates the alignment mark position information from the alignment mechanism 1 and wafer stage position information from the laser interferometer 7 and outputs, based on a result of calculation, a signal for controlling the position of the wafer stage 5.
Explanation will be given about the light exposure method using the light exposure tool.
Prior to exposing the wafer 4 with light, the alignment mark position is measured by the alignment optical system with the wafer 4 mounted on the wafer stage 5 and a shot array on a wafer surface is found from the alignment mark measuring position. The shot array position on the wafer surface can be separated into a linear error Lw, that is, a linear systematic error, and random error (Swx, Swy) in an interfield of the wafer.
The wafer's linear error Lw contains, as shown in FIG. 3A, a translate error (.alpha.x, .alpha.y) in an xy direction, rotation error (an error in a rotation direction of the wafer) .theta.w, a scaling error (Ex, Ey), that is, an error representing an expansion/contraction error, and an orthogonality error .theta.wo in the interfield.
With (dxw, dyx) representing the difference between a designed mark position (x, y) and a mark position obtained by measurement, the mark detection position error on the wafer can be expressed as the functions of the coordinate (x, y) in the interfield given by EQU dxw=.alpha.x-(.theta.w+.theta.wo).multidot.y+Ex.multidot.x+Swx EQU dyw=.alpha.y+.theta.w.multidot.x+Ey.multidot.y+Swy (1)
where
(.alpha.x, .alpha.y): the translate error coefficient in the xy direction; PA1 .theta.w: the rotation error coefficient; PA1 (Ex, Ey): the scaling error coefficient representing the expansion/contraction of the wafer; PA1 .theta.wo: the orthogonality error coefficient; and PA1 (Swx, Swy): the remaining random error coefficient. PA1 .DELTA.xw=.alpha.x-(.theta.w+.theta.wo).multidot.y+Ex.multidot.x PA1 .DELTA.yw=.alpha.y+.theta.w.multidot.x+Ey.multidot.y PA1 (Mx, My): the magnification error coefficient representing an expansion/contraction in the shot; PA1 .theta.s: the shot rotation error coefficient; PA1 .theta.so: the shot skew error coefficient; and PA1 (Ssx, Ssy): the remaining random error coefficient. PA1 a wafer stage having a semiconductor wafer with a plurality of alignment marks formed thereon for position identification; PA1 a wafer stage position measuring mechanism for measuring a position of the wafer stage; PA1 a projection optical mechanism for projecting a circuit pattern onto the wafer to expose a predetermined area of the wafer with beam; PA1 an alignment mechanism for detecting the positions of wafer in an aligned state; PA1 a calculation mechanism for calculation-processing a signal obtained by processing an alignment output signal from the alignment mechanism and output signals obtained from the wafer stage position measuring mechanism; and PA1 a control mechanism which, at a plurality of exposures of the wafer by the projection optical mechanism, controls the alignment mechanism in accordance with an n-th order function (x, y) in an interfield coordinate (x, y) of the wafer by approximating a per-exposure systematic error of at least one of a shot rotation error, magnification error and skew error with the n-th order function Ls (x, y) and corrects the per-exposure systematic error depending upon the interfield coordinate. PA1 effecting calculation-processing by finding at least one of systematic errors Ls (.theta.s, Mx, My, .theta.so) at each of a plurality of shots created on the wafer and approximating at least one of a shot rotation error, magnification error and skew error with an n-th order function Ls (x, y) in an interfield coordinate (x, y) of the wafer; and PA1 effecting control by correcting at least one of a shot rotation (.theta.s), shot magnification (Mx, My) and shot skew (.theta.so), during the writing of the circuit pattern on the wafer, in accordance with the function Ls (x, y).
These linear error coefficients (.alpha.x, .alpha.y, Ex, Ey, .theta.w, .theta.wo) in the interfield of the wafer is found by the calculation device 8 using the least squares method.
The shot position (xw, yw) actually exposed with the light after alignment is given by the following expressions (2) with respect to a designed value (X, Y): EQU xw=X+.DELTA.xw EQU yw=Y+.DELTA.yw (2)
where
On the other hand, the intrafield error of the shot can be separated, as shown in FIG. 3B, into an intrafield linear error Ls (shot rotation, magnification and skew errors) and intrafield random error (Ssx, Ssy). With (dxs, dys) representing the difference between the designed mark position (Xs, Ys) and the mark position obtained by measurement, the position error in the intrafield can be expressed as the functions in the intrafield coordinate (xs, ys) which can be given by: EQU dxs=-(.theta.s+.theta.so).multidot.ys+Mx.multidot.xs+Ssx EQU dys=+.theta.s.multidot.xs+My.multidot.ys+Ssy (3)
where
These linear error coefficients (Mx, My, .theta.s, .theta.so) in the intrafield are found with the use of the least squares method.
In a stepper type light exposure tool of a step-and-repeat light exposure type, it is possible to correct the shot rotation (.theta.s) and isotropic magnification (Mx+My)/2 of the intrafield linear errors Ls.
In the scan type light exposure tool, on the other hand, using a mercury-vapor lamp or other light sources such as an excimer laser and adapted to expose the wafer with the light by moving the wafer and reticle relative to each other while moving the wafer stage and reticle stage, it is possible to, while under the scan light exposure, correct the linear errors Ls (.theta.s, Mx, My, .theta.so) in the intrafield, individually.
Conventionally, the correction of the intrafield linear error Ls has been made by correcting the constant. There occurs a variation in the intrafield systematic errors, depending upon the wafer stage position, such as an error resulting from a variation in the shot rotation by a wafer stage position displacement resulting from a yawing error of the wafer stage 5 and mirror bending (distortion) of the laser interferometer 7 serving as the wafer stage position reference. The correction of such an error resulting from such a variation has not been done in the current practice. With the recent increase in the size of a wafer, such intrafield systematic error varying depending upon the position displacement of the wafer stage has reached a stage where it cannot be disregarded any longer. As set out above, such intrafield systematic error Ls has not been corrected in any conventional light exposure tool and method using the conventional optical stepper, surely presenting a near-future problem.

Exposure tool and method capable of correcting high (N-TH) order light exposure errors depending upon an interfield coordinate


Improved location estimates for transceivers is described. The location estimate of transceivers can be improved for sector transceivers that are co-located at a sectored cell site. The location estimate for each individual co-located sector transceiver can be updated as a centroid of all of the co-located sector transceivers. The location information of the transceivers can be used to provide network location estimation to mobile devices which do not have accurate positioning estimates.

Mobile devices, such as smartphones, tablets and laptops location services enable location based applications or services to be provided on the devices. These services require that the mobile device determine their current location, or an estimate of the location using location technology such as a global positioning system (GPS) receiver. However a GPS receiver or signal may not always be available, or its accuracy too low due to the particular radio frequency environment, and an accurate location for the mobile device may be able to be determined.
It is possible to estimate a location of a mobile device based on a radio scene captured by the mobile device, however an accurate location of the associated transceivers is required to provide location estimate. The radio scene may comprise a plurality of cell identifiers (IDs) and associated received signal strength indicator (RSSI) value from cellular transceivers the mobile device is receiving signals from. If the locations of the transceivers are known, the location of the mobile device can be estimated using trilateration, or more generally n-lateration.
FIG. 1 depicts the use of trilateration for determining a location of a mobile device. In FIG. 1, it is assumed that the person 102 has a mobile device. The mobile device may communicate with numerous cell sites 104a, 104b, 104c having transceivers (referred to collectively as cell sites 104). If the position of the cell sites 104 are known, and a distance 106, 106b, 106c from each of the cell sites 104 to the person 102 is known, it is possible to determine the location of the person using trilateration, which is the case of n-lateration for n=3. The signal strength of signals 108a, 108b, 108c received at the user's mobile device from the cell sites 104 can be used to provide an estimate of the distance the user is from the transceivers of the respective cell sites 104. The mobile device may provide a current radio scene to a location service that can provide the required location information of the cell site. The location service can perform the trilateration and return the estimate of the mobile device's location back to the mobile device, which can then use the estimated location as desired.
FIG. 2 depicts an illustrative representation of determining a location of a cell site. The cell site 202 communicates with a plurality of users 204a, 204b, 204c, 204d, 204e, 204f (referred to collectively as users 204), or more precisely the mobile devices of the users 204, that are within a transmission radius 206 of the transceiver of the cell site 202. If the locations of the users 204 are known as well as the distances 208a, 208b, 208c, 208d, 208e, 208f from the users 204 to the cell site 202, the location of the cell site 202 can be determined. Additionally or alternatively, if a large number of users provide their location information, the location of the cell site can be estimated as a centroid of the provided mobile device locations.
While the above technique for determining a cell site's location as a centroid of mobile device positions works well if the users providing their location information are evenly distributed about the transceiver of cell site, the technique will provide a location estimate with a larger error if the users are not evenly located about the transceiver of the cell site, as may be the case for co-located transceivers of sectored cell sites.
As described above, in order to provide a location service when GPS information is not available or is inaccurate from the mobile device, the location of cell sites must be known to use network based location techniques. Although the wireless carriers, or infrastructure service providers, that operate the wireless network will know the location of the cell sites to a high degree of accuracy and can use network based location techniques to determine a location of a mobile device, this information is often not available to third parties or applications that may wish to provide location services to mobile devices. As such, it is necessary to be able to accurately determine the location of cell sites in a network in order to provide location services without relying on service provider location information.
Therefore there is a need for a system and method for improved location estimates of co-located sectored cell sites.

System and method for improving location estimates of co-located sectored cell sites for location services


An integrated circuit chip package according to the present invention includes an integrated circuit chip mounted on a substrate by a plurality of solder bumps. A mold compound is used for underfilling air gaps between the chip and the substrate. The integrated circuit chip package is formed by placing the chip and substrate within a mold cavity and pressing a transfer mold compound into the mold cavity. Air spaces between the integrated circuit chip and the substrate are underfilled by the mold compound as it is pressed in between the integrated circuit chip and the substrate. Air is allowed to escape from between the chip and the substrate during the underfilling through a vent which extends through the substrate. The underfilling material may also be used to encapsulate the chip at the same time that underfilling is performed.

The invention relates to an integrated circuit chip mounting system and more particularly, to an integrated circuit chip package and a method of electrically connecting and mounting integrated circuit chips to a substrate.
Flip chip technology is well known in the art for electrically connecting an integrated circuit chip to an integrated circuit substrate or package. Formation of one type of flip chip involves forming solder bumps on electrical interconnection pads on the active or front side of a semiconductor chip. The chip with solder bumps is then inverted onto a laminate substrate with the solder bumps aligned with metal circuits provided on the substrate. The solder bumps on the chip are then soldered to the metal pads on the substrate by melting the solder in a reflow furnace. A solder joint is formed by the reflowing of the solder between the semiconductor chip and the substrate. After the chip has been attached to the substrate by the reflow soldering process, narrow gaps are present between the solder bumps.
The substrate is typically comprised of a ceramic material or a polymer composite laminate, while the chip is formed of silicon. Due to these different materials, there is a mismatch in the coefficient of thermal expansion between the semiconductor chip and the substrate on which the chip is mounted. During temperature cycling the semiconductor chip and substrate expand and contract at differing rates. Accordingly, the soldered joints between the semiconductor chip and the substrate will have a tendency to fail because of the coefficient of thermal expansion mismatch. In addition, because of the very small size of the solder joints, the joints are subject to failures.
The strength of the solder joints between the integrated circuit chip and the substrate are typically enhanced by underfilling the space between the semiconductor chip and the substrate and around the solder joints. The underfill material is typically a polymer adhesive which reduces stress on the solder joints.
The conventional method of underfilling includes dispensing the underfill material in a fillet or bead extending along two or more edges of the chip and allowing the underfill material to flow by capillary action under the chip to fill all the gaps between the semiconductor chip and the substrate. The solder bumps create a very narrow gap between the semiconductor chip and the substrate which is about 0.002-0.005 inches (0.051-0.127 mnm). Therefore, the underfill material which is capable of flowing through these narrow gaps contains only a small amount of filler material because the filler material will prevent the underfill material from flowing easily into the gaps. This type of underfill material with a low amount of filler material has an extremely high mismatch of coefficient of thermal expansion with the semiconductor chip, the solder bumps, and the substrate. Accordingly, it would be desirable to use an underfill material having more filler and thus, less of a thermal expansion coefficient mismatch with the substrate and chip.
An example of an integrated circuit chip 100 which has been attached to a substrate 102 by solder balls 104 and underfilled by a conventional method is illustrated if FIGS. 3 and 3a. The underfill material 106 has been drawn into the spaces between the solder balls 104 by capillary action to fill the air spaces between the integrated circuit chip 100 and the substrate 102.
The use of capillary action to suck the underfill material into the gap between the integrated circuit chip and the substrate takes between 5 and 20 minutes, depending on many factors including the size of the chip and the underfill material used. Another drawback of the conventional underfilling method is the occurrence of voids in the underfilling material.
Accordingly, a need exists for an underfilling method for completely filling the spaces between an integrated circuit chip and a substrate which can reliably underfill at a faster rate than known methods.
An integrated circuit chip package according to one aspect of the present invention includes an integrated circuit chip having an active surface with interconnection pads disposed thereon, and a substrate having a first surface with bonding pads substantially corresponding to the interconnection pads of the integrated circuit chip and a second side having a plurality of solder pads electrically interconnected with the bonding pads. A vent hole extends from the first side to the second side of the substrate, and is positioned beneath the integrated circuit chip when the chip is mounted on the substrate. A plurality of solder bumps electrically connect the interconnection pads of the integrated circuit chip with the bonding pads on the first side of the substrate. A molded underfill material is molded around the integrated circuit chip. The molded underfill material surrounds the solder bumps between the integrated circuit chip and the substrate and extends into the vent hole in the substrate.
A further aspect of the present invention relates to a method of underfilling an integrated circuit chip which has been electrically interconnected to a substrate. The method includes the steps of placing the integrated circuit chip and substrate within a mold cavity, injecting a mold compound into the mold cavity, underfilling a space between the integrated circuit chip and the substrate with the mold compound by the pressure of injection of the mold compound into the mold cavity, and allowing air to escape from between the integrated circuit chip and the substrate during underfilling through a vent in the substrate.
The present invention addresses the deficiencies of known underfilling methods by underfilling faster and more reliably than the known methods. In addition, the present invention forms an encapsulated integrated circuit chip package and performs underfilling in the same step.

Method of underfilling an integrated circuit chip


A method of detecting an edge within digitized images, said method comprising steps of: (a) obtaining said image in a digital form; (b) building a 3D graph of intensity distribution within said image; (c) finding Regions of Interest ROI in the image and subtracting out the background; (d) establishing edge lines within said image; establishing a resultant edge line for each ROI by averaging or maximizing the set of independently obtained edge lines corresponding to said plurality of criteria but that differ from each other by a margin increasing with a predetermined increment; and (f) generating at least one report presenting the quantitative and/or qualitative parameters in a form of accurate quantitative measurements and qualitative inferences regarding medical and general diagnosis of the images and patients utilizing one or more output modules.

The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Importantly, although the operational/functional descriptions described herein are understandable by the human mind, they are not abstract ideas of the operations/functions divorced from computational implementation of those operations/functions. Rather, the operations/functions represent a specification for the massively complex computational machines or other means. As discussed in detail below, the operational/functional language must be read in its proper technological context, i.e., as concrete specifications for physical implementations.
The logical operations/functions described herein are a distillation of machine specifications or other physical mechanisms specified by the operations/functions such that the otherwise inscrutable machine specifications may be comprehensible to the human mind. The distillation also allows one of skill in the art to adapt the operational/functional description of the technology across many different specific vendors' hardware configurations or platforms, without being limited to specific vendors' hardware configurations or platforms.
Some of the present technical description (e.g., detailed description, drawings, claims, etc.) may be set forth in terms of logical operations/functions. As described in more detail in the following paragraphs, these logical operations/functions are not representations of abstract ideas, but rather representative of static or sequenced specifications of various hardware elements. Differently stated, unless context dictates otherwise, the logical operations/functions will be understood by those of skill in the art to be representative of static or sequenced specifications of various hardware elements. This is true because tools available to one of skill in the art to implement technical disclosures set forth in operational/functional formats—tools in the form of a high-level programming language (e.g., C, java, visual basic, etc.), or tools in the form of Very high speed Hardware Description Language ("VHDL," which is a language that uses text to describe logic circuits)—are generators of static or sequenced specifications of various hardware configurations. This fact is sometimes obscured by the broad term "software," but, as shown by the following explanation, those skilled in the art understand that what is termed "software" is a shorthand for a massively complex interchaining/specification of ordered-matter elements. The term "ordered-matter elements" may refer to physical components of computation, such as assemblies of electronic logic gates, molecular computing logic constituents, quantum computing mechanisms, etc.
As outlined above, the reason for the use of functional/operational technical descriptions is at least twofold. First, the use of functional/operational technical descriptions allows near-infinitely complex machines and machine operations arising from interchained hardware elements to be described in a manner that the human mind can process (e.g., by mimicking natural language and logical narrative flow). Second, the use of functional/operational technical descriptions assists the person of skill in the art in understanding the described subject matter by providing a description that is more or less independent of any specific vendor's piece(s) of hardware.
Scientific endeavors generally require precise and accurate quantification to determine results. In medicine, and in the field of cardiology in particular, the results obtained from various tests are used in further decision-making regarding the patient including accurate diagnosis and treatment. Many tests, especially those involving imaging, provide results that require great skill to analyze by a trained expert or specialist. Due to the huge amount of information presented in an image and the lack of accurate fully automated systems for analysis, the field of medicine is frequently left to semi-quantitation (e.g., grade on a 1 to 4 scale). While this may be adequate for many purposes, observer bias, lack of reproducibility, and lack of the ability to be precise often results in the need for more testing to try to be certain of the diagnosis, or painstaking effort by the physician to make sure the treatment is given in the effective regions (e.g., that the proper location on the field of image is treated by X-rays, etc.). The ability to perform rapid and accurate quantification using computer-assisted image analysis can be a great aid in these fields.
Currently there have been great limitations in the full automation of image analysis. There are edge-detection system and methods available that look for a general change in the picture but generally require noise subtraction and input from a user to focus on the areas of interest or from an encyclopedic database to compare the image to in order to identify or delimit the object of interest in the image. The edges detected are generally based on first and second differentiation and are binary (edge present/absent) but not qualitative (do not reflect information about different types of edges present). Users of current processes need frequent and direct operator input to effectuate an analysis.
None of the current technologies and prior art, taken alone or in combination, address nor provide a utility solution for fully automated diagnostic data analysis and image quality assessment based on the extraction of predefined parameters from the input of data to be used for further reporting as accurate quantitative measurements and qualitative inferences regarding medical and general diagnosis of patients.
Specific uses and applications of this process include the field of coronary angiography and echocardiography. The raw images obtained in these arts including cineangiograms of the coronary arteries and echo images of the cardiac chamber walls until presently have not readily been amenable to accurate fully automated analysis of artery caliber (diameter along its length to evaluate amount of stenosis) or chamber dimensions and wall thickness.
In coronary angiography until present the cardiologist has had to estimate the percent stenosis along the length of the artery as revealed by the gold standard coronary angiogram (luminogram) or by other techniques including intravascular ultrasound or Computerized Tomographic (CT) scan. However, actual automation of this analysis is burdensome and currently has been inaccurate and therefore unreliable. Using the new detection methods inside a larger method of straightening the artery so that perpendicular cuts are obtained for measurement is providing the ability for both a fully automated and a more accurate analysis of the whole length of the artery.
In echocardiography field, there is currently no fully automated method of measuring cardiac chamber borders and dimensions. The input of the technologist is required in multiple steps of the image analysis. The new method is being developed to enable fully automated chamber measurements and wall thickness analyses and ejection fraction calculation. This would enable accurate noninvasive hemodynamic and cardiac output determinations.
Furthermore, great promise is expected in the field of artificial vision. By comparing two pictures temporally or side-by-side, with the fine resolution and discriminating abilities of the new method, the distances and dimensions of objects will be quickly amenable to calculation. By efficiently and automatically determining the shape and size of the object, automated identification should be greatly improved.
Further uses include the field of CT and MRI (magnetic resonance imaging) and ultrasound scans. The ability to accurately automatically measure chamber edges is expected to allow for automated analysis of normal and abnormal and for generation and comparison to encyclopedic database for further refinement of the art and science besides improving diagnosis and treatment for each individual patient. Another use would be for automated identification and marking of an organ edge for radiation therapy, for example.
WO2017168424 discloses a method of analyzing and assessing an image comprises the steps of: (a) obtaining said image in a digital form; (b) processing said image; and (c) establishing at least one edge line within said image. The step of processing said image further includes: (a) building a 3D graph of intensity distribution within said image; (b) calculating identifying vector angle values (IVAVs); said angles adjoin to points of said 3D intensity distribution graph which correspond to individual pixels of said image; said angles lie in a plane defined by an intensity axis of said image; (c) setting a range of lower and upper thresh-hold level values (THLV1 and THLV2) between which edge points are indicatable; and (d) indicating edge points according to said THLV1 and THLV2.
Accuracy of edge detection largely depends on the set THLV1 and THLV2 values. There is a long-felt and unmet need for a method and a system where dependence of a position of an edge detected in grayscale images is neutralized and made independent of specific absolute values of the grayscale (and specific threshold THLV values).

System and methods for fully automated data analysis, reporting and quantification for medical and general diagnosis, and for edge detection in digitized images


Column/I-beam interconnect structure including an attaching plate joined to an I-beam end. This plate possesses, along its lateral margins, angularly oriented upper and lower through-passages, each characterized with a reception axis, and designed to receive, along that axis, portions of a hex nut-and-bolt set which is used to clamp together two adjacent, angularly related attaching plates. The socket portions, or outer chambers, of the through-passages are formed with spaced and generally parallel-planar upper and lower surfaces which act in these socket portions to restrain a received hex nut against rotation about its own rotational assembly axis which, in the socket portion, is coincident with the socket portion's reception axis. This arrangement uniquely allows for a structural configuration wherein laterally directed moment loads are transferred very closely relative to the elevations of such beams' flanges, and more specifically, as close as possible to key axes of force transmission such as those that lie laterally centrally in the planes of these flanges.

This invention relates to column/beam interconnect structure, and in particular to such structure which is employed to interconnect structural columns and beams that are employed in a building frame structure to handle both gravity and moment loads. This structure is also referred to herein as beam-to-column attaching structure.
A preferred embodiment of the invention is described and illustrated herein in the context of interconnecting square cross-section, hollow, steel columns and steel I-beams through interengageable inner an outer collar structures that are interposed a column and a beam. More specific details of such collar structures per se, beyond those which are pictured and described herein to disclose the present invention, can be found in currently co-pending Regular U.S. patent application Ser. No. 09/943,711, filed Aug. 20, 2001, for "Moment-Resistant Building Frame Structure Componentry and Method". Accordingly, reference is here made to that application as a source of background information.
Where columns and beams of the type mentioned above interconnect, and with specific attention paid to the issue of how such an interconnection is designed to handle moment loads, the regions of adjacency of the ends of upper and lower I-beam flanges and the nearby sides of columns are especially important. In these regions, the more that it is possible to assure that laterally directed moment loads are transferred very closely relative to the elevations of such beams' flanges, and more specifically, as close as possible to key axes of force transmission, such as those that lie laterally centrally in the planes of these flanges, the better is the use that is made of the full capabilities of such columns and beams to manage moment loads.
The present invention addresses this matter in unique, special and effective ways by helping to assure, in particular, that lateral moment loads are so transferred. With reference to the inner and outer collar structures mentioned above, and in accordance with implementation of the present invention, socket-drive hex nut-and-bolt sets are employed to clamp each outer collar to an associated inner collar. The inner collar includes a plurality of inner plate components (also referred to as attaching plates), one for each face of a column, suitably attached, as by welding, to the column faces. In the context of describing the present invention, a column has four, orthogonally related faces. The inner collar plate components employed for such a column thus are four in number, and when distributed at a particular longitudinal location along a column, "wrap" around the column, and meet one another, lateral edge to lateral edge, at right-angle corners.
The outer collar is also formed of four plate components, or plates, at least some of which are attached, also as by welding, to the ends of I-beams. The number of such outer collar plates attached to beam ends at a given collar connection with a column is determined by the number of beams that are to be connected to the column at that point. These plates, which are anchored to the ends of I-beams, are substantially planar in nature, and possess spaced inner and outer faces which, with interconnected columns and beams in place, face the outside of the column and the confronting near end of a connected I-beam, respectively. These inner and outer faces are also referred to herein respectively as "other" and "one" faces, and the outer collar plates are referred to collectively as angular-modularity plates.
The inner and outer collar plate components are provided with gravity-seating/locking, complementary mating structure, and the vertical lateral edges of the outer-collar plate components are provided with suitably angled (45° in the illustration now being given) through-bores and outer sockets, or outer chambers, that align across corners when two such components are properly orthogonally (angularly) positioned relative to two inner collar plate components that are attached to two orthogonally adjacent faces in a column.
The mentioned nut-and-bolt sets, or assemblies, are employed in such aligned through-bores and sockets, with the head of each bolt received within one of the associated sockets and with the nut received in the other associated socket. These nut-and-bolt sets are appropriately tightened to clamp a fully assembled outer collar structure onto a receiving inner collar structure. When so tightened, the nut-and-bolt sets join adjacent outer-collar plates, and participate as tension elements with respect to the handling of moment loads between a column and a beam.
Significantly, the present invention proposes an arrangement wherein pairs of vertically spaced nut and bolt sets are disposed, elevationally, very close to (but within the space between) the two spaced planes which are occupied by the upper and lower flanges in an associated, adjacent, anchored-to I-beam. They thus are positioned in a manner to maximize their capabilities for moment load handling. This "close to" spacing is uniquely permitted because of the fact that the sockets in each associated through-bore and outer socket structure are formed with vertically spaced, substantially parallel-planar surfaces which provide modest clearance for receiving two of the usual diametrally spaced parallel-planar surfaces on the outside of a hex nut, with these two sides of that nut closely confronting these socket-structure surfaces, thus to prevent the nut from rotating in a socket about it own "assembly axis" which co-aligns with the axis of alignment associated with that socket. The nut-and-bolt assemblies discussed herein are referred to as having assembly axes which are those axes about which relative rotation between an associated nut and bolt takes place.
Given this configuration, a nut-and-bolt set can be tightened simply by rotating the socket-drive bolt head in the set without the need for using any tool to prevent nut rotation. Were the structure which has just been described, configured differently to require the use, for example, of a wrench to hold a nut against rotation, larger socket space would have to be provided to accommodate the insertion of such a wrench so as to be able to grip the nut. Such an accommodation would be accompanied by a requirement that upper and lower nut-and-bolt sets, and specifically their axes of force transmission, not be so closely spaced to I-beam upper and lower flanges, and a consequence of this would be that the effective movement-handling capabilities of a nut-and-bolt set would be diminished for the reason suggested earlier relating to proximity to the "key" axes of beam/column force transmission that lie centrally in the planes of a beam's flanges. Also, this would mean that each outer collar plates would have to have more material removed in order to provide wrench access to a nut, and the associated outer collar plate per se would, accordingly, be somewhat weakened in comparison with such a plate prepared in accordance with this invention.
These and other features and advantages which are offered by the present invention will become more fully apparent as the description which now follows is read in conjunction with the accompanying drawings.

Column/beam interconnect nut-and-bolt socket configuration


In a reactive force pedal device, between a motor-side output shaft and a pedal member, a one-way clutch is provided which allows transmittance of rotational force when performing a depressing operation of the pedal member and disables transmittance of the rotational force when performing a revert operation of the pedal member.

There is known an arrangement for applying a reaction force from an actuator to an accelerator pedal depending on the amount through which the accelerator pedal is operated {for example, Japanese Laid-Open Patent Publication No. 2007-026218 (hereinafter referred to as "JP2007-026218A")}. According to JP2007-026218A, an accelerator pedal 3 and a servomotor 19 are operatively coupled to each other by a pedal lever 5 and an arm 15. The servomotor 19 has a drive shaft 19b supporting on a distal end thereof a gear 19a that is held in mesh with a gear segment 15b on the pedal lever 5. The servomotor 19 applies a reaction force through the above structure to the accelerator pedal 3 (see Abstract and FIG. 1).
According to Japanese Laid-Open Patent Publication No. 2005-132225 (hereinafter referred to as "JP2005-132225A"), a depressing force changing means which comprises a variable friction plate 7, a fixed shaft 8, and an actuator 9 (e.g., an electromagnetic solenoid) is used to indicate a switchover of driving characteristics to the driver of a vehicle (see Abstract and [0011]). According to JP2005-132225A, furthermore, a one-way clutch 12 is disposed between a rotational shaft 3 to which an accelerator pedal 2 is fixed and the variable friction plate 7 (FIG. 10). When the accelerator pedal 2 is returned, the one-way clutch 12 prevents a frictional force of the variable friction plate 7 from being transmitted to the rotational shaft 3 (see [0038]).


A process for providing illumination source conditions for the accurate determination Zernike tilt coefficients in the presence of coma is described. Large feature-shift coma sensitivity is simulated for a range of illumination conditions. The resulting source sensitivity data is modeled and a practical array of source shapes, each of which is optimized to eliminate the effects of transverse distortion due to third-order coma, is identified. The optimized set of source shapes can be used to more accurately determine Zernike terms a2 and a3 using a variety of methods. Knowledge of the lens distortion data in the absence of coma induced shifts can be entered into more traditional overlay regression routines to better identify systematic and random error. Additional applications of the above outlined procedure include: improved lithographic simulation using conventional optical modeling software and advanced process control in the form of feedback loops that automatically adjust the projection lens for optimum system performance.

1. Field of the Invention
The present invention relates generally to optical metrology and more particularly to methods for the determination of intra-field distortion and lens aberrations for projection imaging systems used in semiconductor manufacturing.
2. Description of the Related Art
Semiconductor manufacturers and lithography tool vendors have been forced to produce higher numerical aperture (NA) lithography systems (steppers or scanners) using smaller wavelengths (for example, 193 nm DUV lithography) in response to the semiconductor industry's requirement to produce ever-smaller critical features. See, for example, the statement of the well-known "Moore's Law" at "Cramming More Components Onto Integrated Circuits", G. Moore, Electronics, Vol. 38, No. 8, 1965. The ability to produce (manufacture) sub-wavelength features can often be determined by considering the rather simple (3-beam) Rayleigh scaling Resolution (R) and Depth-of-Focus (DoF) equations: ˜λ/2NA and ˜λ/2NA2. See "Introduction to Microlithography", L. Thompson et al., ACS, 2nd Edition, 1994, p. 69. These coupled equations stress the inverse relationship between resolution and DoF based on the exposure wavelength (λ and numerical aperture (NA), for features printed near the limit of the optical system. High NA lithography (including immersion lithography) has led to improved resolution and a reduction in the overall focus budget, making lithography processes difficult to control. See "Distinguishing Dose from Defocus for In-line Lithography Control", C. Ausschnitt, SPIE, Vol. 3677, pp. 140:147, 1999, and "TWINSCAN 1100 Product Literature" ASML. In addition, the push for faster product development, reduced cycle time, and better cost management often means that photolithographic exposure tools (steppers and scanners) are pushed beyond performance specifications, where lens aberrations and exposure source variations become critical to monitor and understand. See "Impact of Lens Aberrations on Optical Lithography", T. Brunner, IBM, Vol. 41, pp. 1:2, 1997 (available at the URL of www.research.ibm.com). Aberrations (wave front deviation), defined as the deviation of the real performance of a projection lens from ideal performance, can be mathematically formulated a number of ways, but in each case the result is a mathematical description of the phase error across the lens pupil. See, for example, "Basic Wavefront Aberration Theory for Optical Metrology", J. Wyant, K. Creath, ISBN 0-12-408611-X, Chapter 1, pp. 1-53, 1992. Lens aberrations are typically responsible for both local (field dependent) transverse error (feature-shift) and critical dimension variation (feature shape error). The present discussion will be concerned with aberrations responsible for transverse error, stemming from both source and lens. We use a rather general Zernike aberration convention, where A0, 0, 1 and A0, 0, −1 (or a2 and a3) are the Zernike x-tilt, y-tilt coefficients, where A0, 3, −1 and A0, 3, 1 (or a8 and a7) are the Zernike coma-x, coma-y coefficients, and where O(ax) represents higher order aberrations, each of which is responsible for some portion of transverse distortion and possibly other effects. Several methods exist for determining transverse distortion as function of field position using overlay metrology. See "Analysis of Overlay Distortion Patterns", J. Armitage, J. Kirk, SPIE, Vol. 921, pp. 207:221, 1988, "Method and Apparatus for Self-Referenced Projection Lens Distortion Mapping, A. Smith et al., U.S. Pat. No. 6,573,986 issued Jun. 3, 2003, and "Method and Apparatus for Self-Referenced Dynamic Step and Scan Intra-Field Lens Distortion", A. Smith, U.S. patent application Ser. No. 10/252,020 filed Sep. 20, 2002. However, the ability to precisely determine the Zernike coefficients (a2 and a3) depends on the ability to separate out the distortion effects of (low order) coma since both aberrations give rise to feature-shift. The third-order coma (x-coma, y-coma or both), or the effects from third-order coma, can occur when image contributions from different pupil radii shift relative to one another, as described by Equation 1 below, a generalized Zernike polynomial (of the third-order) for the optical path difference (OPD):OPD(Z7, Z8)=factor*(3ρ3−2ρ*sin(φ), cos(φ) or factor*(3ρ2−2)*Z2, Z3  (Eq. 1)where Z8, Z7 represent the Zernike polynomials for x-coma and y-coma, ρ is the exit pupil radius, φ is the angular position in the pupil, and Z2, Z3 represent the Zernike polynomials for x and y field tilt. See "Impact of Lens Aberrations on Optical Lithography", supra, for discussion of Zernike polynomials.
Equation 1 shows clearly that rays (for geometric descriptions) passing near the center of the pupil deviate differently than rays near the edge of the pupil. These ray deviations cause both CD variation (asymmetric feature patterns) and feature-shift. The variation in phase across the exit pupil in the presence of x-coma, for example, is shown in FIG. 1a. Since most photolithographic exposure tools allow for different source shapes, the feature dependent shift is also a function of source shape and varies slowly across the exposure field or scanning slot. In the presence of coma, a small pin hole (opening<<transverse resolution) on a reticle is imaged into a comet-type object, as shown in FIG. 1b. Finally, since lithographic features are created by the complex superposition of many small aberrated point sources, the resulting feature shapes generally depend on both the size and orientation of the reticle patterns.
Detailed and accurate knowledge of the aberrations (especially those related to transverse distortion) can be fed directly into (inter and intra-field) overlay modeling and control routines to improve overlay performance, since the overlay control models (for example, models such as Klass II and Monolith) require understanding of all sources of distortion or transverse displacement. See "Analysis of Overlay Distortion Patterns", supra, and "Mix-and-Match: A Necessary Choice", R. DeJule, Semiconductor International, pp. 66:76, February 2000. Overlay registration, or misregistration, is the translational (positional) error that exists between features exposed layer to layer in the vertical fabrication process of semiconductor devices on silicon wafers. Typically, alignment attributes or overlay targets are used to determine the magnitude of the error (see FIGS. 2a-2b). Other names for overlay registration include registration error and pattern placement error; for this description, the terms "overlay error" or "error" will be used. An overview of overlay modeling and control schemes can be found in "Analysis of Overlay Distortion Patterns", supra, "Measuring Fab Overlay Programs", R. Martin et al., SPIE Metr. Inspection, and Process Control for Microlithography, XIII, pp. 64:71, March 1999, and "Method for Overlay Control System", C. Ausschnitt et al., U.S. Pat. No. 5,877,861 issued Mar. 2, 1999. Finally, in addition to lateral shifts, distortion related aberrations are also responsible for degrading image fidelity (or modulation), proportional to the variance of the distortion along the scanning direction. Given details of the lens distortion, those of skill in the art can generally make changes in the configuration of the slit geometry and improve imaging performance.
There are various sources of overlay error for both targets and patterned features. See, for example, "The Waferstepper Challenge: Innovation and Reliability Despite Complexity", Gerrit Muller, Embedded Systems Institute Netherlands, pp. 1-10, 2003. These overlay error sources include reticle (tilt, pattern misplacement, warp), source (telecentricity, source settings), overlay mark fidelity, feature dependent processing error, wafer (topography, flatness), lens (aberrations, telecentricity), stage (static and dynamic stage error global alignment), overlay measurement (tool induced shift, precision), and tool matching (stage, lens, matching accuracy). See, for example, "Thinking Outside the Box for Improved Overlay Metrology", I. Pollentier et al., SPIE Microlithography Proceedings, Vol. 5038, pp. 12:16, 2003, and "Method and Apparatus for Self-Referenced Dynamic Step and Scan Intra-Field Scanning Distortion", A. Smith, U.S. patent application Ser. No. 10/252,021 filed Sep. 20, 2002. It is interesting to note that the overlay error associated with large feature alignment attributes only approximates the overlay error associated with the actual printed circuit features since features for a variety of reasons including: size differences, pattern placement error, inherent overlay mark error, source/aberration coupling.
Over the past 30 years the microelectronics industry has experienced dramatic rapid decreases in critical dimension (feature-size) by constantly improving photolithographic imaging systems and developing new reticle enhancement techniques. See, for example, "Resolution Enhancement with OPC/PSM", F. Schellenberg, Future Fab International, Vol. 9, 2000. Photolithographic imaging systems are often pushed to and beyond performance limits. As the critical dimensions of semiconductor devices approach 50 nm (and below), the overlay error requirements will soon approach atomic dimensions, making overlay process control extremely difficult. See "International Technology Roadmap for Semiconductors, 2001 Edition", SEMATECH, pp. 1-21. New methods for identifying and quantifying the sources of overlay error will become vital. In particular, methods for accurately determining lens aberrations (especially low order distortion) and source irregularity and their coupled effects on image fidelity and overlay will remain critical. Finally, another area where quantifying distortion error is of vital concern is in the production of photomasks (and direct-write lithography) during the electron beam (including; laser, multi-mirror, ion-beam) manufacturing processes. See "Handbook of Microlithography, Micromachining, and Microfabrication", P. Rai-Choudhury, SPIE Press, Microlithography, Vol. 1, pp. 417, 1997.
Aberration and Source
Some examples of typical illumination source or illumination geometry for photolithographic imaging systems are illustrated in FIG. 3. Several good references on aberrations and their effects on lithographic imaging can be found in the literature. See, for example, "Aberration Measurement of Photolithographic Lenses by Use of Hybrid Diffractive Photomasks", J. Sung et al., Applied Optics, Vol. 42, No. 11, pp. 1987-1995, Apr. 10, 2003, and "Impact of Lens Aberrations on Optical Lithography", supra. The effects of third-order coma on pattern shift are fairly well-known and numerical methods can be used to ray trace or model the behavior (determine pattern shift as a function of source shape, feature size and optical parameters) when the Zernike terms are known. In general, the coma aberration can be split into two terms, x-coma and y-coma. Where x-coma is responsible for shifting and/or degrading vertical features and y-coma shifts and/or degrades horizontal features. Since, in general, the Zernike polynomial expansion contains many significant terms (up to several hundred depending on the lens) it is hard to perform lithographic experiments that isolate the effects of one particular Zernike term, without complex assumptions. See, for example, "Experimental Assessment of Pattern and Probe-Based Aberration Monitors", G. Robins, A. Neureuther, SPIE, Microlithography Proceedings, Vol. 5040-149, pp. 1:12, 2003, and "Aberration Measurement of Photolithographic Lenses by Use of Hybrid Diffractive Photomasks", supra. One method of determining the Zernike coefficients using an in-situ interferometer is described in "Apparatus, Method of Measurement and Method of Data Analysis for Correction of Optical System", A. Smith et al., U.S. Pat. No. 5,828,455 issued Oct. 27, 1998.
Distortion
A conventional method for determining lens distortion in the presence of aberrations (FIG. 1c) is described in "Analysis of Image Field Placement Deviations of a 5× Microlithographic Reduction Lens", D. MacMillen et al., SPIE Vol. 334, pp. 78-89, 1982, where it is tactically assumed that the stepper or scanner wafer stage moves in a nearly perfect manner. Under the assumptions of a perfect wafer stage (stage error small and randomly distributed) one prints a large array of box-targets or alignment attributes (FIG. 2a) across the exposure field. Next, the stepper or scanner is programmed to step and print one small overlay target box inside each of the previously imaged field points (creating readable alignment attributes or a box-in-box target) using a constant aberration portion of the lens. One then determines (estimates) the lens distortion by measuring the feature-shift of the array (FIG. 1d) using an optical metrology tool and several modeling equations that account for additional overlay errors and statistical fluctuations. See, for example, "Measuring Fab Overlay Programs", supra, "KLA 5105 Overlay Brochure", KLA-Tencor, "Quaestor Q7 Brochure", Bio-Rad Semiconductor Systems, and "Measuring Fab Overlay Programs", supra. In general, it is common to ignore the effects of third-order or higher coma on large-feature-shift and to assume that the large-pattern shifts are entirely due to the effects of Zernike tilt terms of low order (a2 and a3 for example) or other easily modeled global shifts. In fact, as mentioned previously, even semiconductor fab overlay procedures disregard the effects of coma on overlay targets altogether.
Several preferred methods for determining lens distortion for steppers (or scanners) are described by A. Smith in U.S. patent application Ser. No. 10/252,021, supra, U.S. patent application Ser. No. 10/252,020, supra, and U.S. Pat. No. 6,573,986, supra. Smith describes a sequence of lithographic exposures and measurements using a novel reticle pattern to mathematically solve for lens distortion in the presence of stage noise and synchronization error. In addition, these preferred methods can be used to determine the Zernike tilt coefficients (a2 and a3) by subtracting off the effects of third-order (or higher order aberrations) if the aberrations for the lens are known. If the aberrations are not known then techniques such as those described by U.S. Pat. No. 5,828,455 can be used to determine the Zernike coefficients (x-coma and y-coma a8 and a7 for example) as a function of field position for both steppers and scanners. Once the coma coefficients are known (as a function of field position), a2 and a3 can be determined by subtraction.
For the preferred methods such as described in U.S. patent application Ser. No. 10/252,020, supra or U.S. Pat. No. 6,573,986, supra, lens distortion is determined by measuring arrays of alignment attributes (using standard overlay methods), solving a complex system of equations and then subtracting off both global and statistical sources of error. The results for lens distortion can be reduced to a simple linear combination of X, Y tilt and X, Y primary (third-order) coma, where higher order contributors are ignored. This relationship is shown in Equation 2.(DX, DY)=(a2*dX/da2+a8*dX/da8, a3*dY/da3+a7*dY/da7)  (Eq. 2)where:                DX, DY represent field dependent pattern shifts as determined by the technique of U.S. patent application Ser. No. 10/252,020, supra, U.S. Pat. No. 6,573,986 and the like;        a2, a3 are Zernike x-tilt and y-tilt coefficients, each a function of field position;        a7, a8 are primary Zernike y-coma and x-coma coefficients, each a function of field position;        dX/da2=dX/da3=(x,y) tilt shift coefficients=−λ/na*π;        dX/da8, dY/da7=(x,y) coma shift coefficients=complex function of source shape and feature pattern; and        λ, NA=projection tool wavelength, exit pupil NA
In general, if the coma coefficients a7 and a8 are known (across the exposure field or slot) one then calculates (simulates) feature-shift versus coma coefficient (a7, a8 or both) for a given source shape and feature-size and arrives at a good estimate of dX/da8 and dY/da7. Then, a2 and a3 can be estimated by manipulation of Equation 2.a2, a3=[(DX−a8*dX/da8)/(dX/da2),(DY−a7*dY/da7)*dY/da3)].  (Equation 3)
While several methods are known for determining lens distortion, an improved determination of lens distortion can be obtained if the cross coupling effects of third-order coma and tilt on transverse distortion are reduced or eliminated. These known methods would need knowledge of the Zernike coefficients (especially third-order coma) as a function of field position to eliminate the cross coupling effects of third-order coma and tilt on transverse distortion. Therefore, it would be desirable to have a process for determination of a2 and a3 in the presence of low order coma aberrations when it is not possible or convenient to determine a complete set of Zernike coefficients for a lens system and process.

Process for determination of optimized exposure conditions for transverse distortion mapping


A sheathed-element glow plug for self-igniting internal combustion engines has an electrical heating element which projects into a combustion chamber of the internal combustion engine, and a current feed-through for providing a heating current for the heating element through an opening in the combustion chamber. A switch is positioned in the region of the current feed-through, and the heating current may be controlled by the opening and closing of the switch.

Glow plugs are known, for example, from published German Patent Application No. DE 28 02 625. Such a sheathed-element glow plug includes a tubular metallic housing which bears a thread on its outer circumference, by way of which the sheathed-element glow plug is screwed into the cylinder. At the end of the housing of the sheathed-element glow plug nearest to the combustion chamber, a glow element is enclosed by the housing and cantilevered so that it reaches towards a sheathed-element glow plug built into the engine. A heating device is arranged in the glow element which, at the combustion chamber end, makes contact with the closed bottom of the glow element to make a ground connection, and at the end away from the combustion chamber makes contact with the supply voltage via a contact stud. Ceramic glow plugs are also known, in which the part reaching into the combustion chamber is made of ceramic. In the known glow systems, the current through the heating device is switched on or off by a preheating time control unit via a switch (relay, power transistor).


A monitor system includes a display panel, a storage case receiving the display panel, a support member movable in the storage case, arm members, first guides in the storage case, and second guides in the support member. The support member rotatably supports the lower end of the display panel. Each arm member has a first supporting point, a second supporting point, and an intermediate supporting point. Each arm member is connected to the display panel through the first supporting point. The second supporting points of the arm members are engaged with the first guides. The intermediate supporting points thereof are engaged with the second guides. In the monitor system with this structure, when the support member is moved forward, the display panel can be rotated upward with a relatively small force such that the display panel is brought from a horizontal posture to a raised posture.

1. Field of the Invention
The present invention relates to a monitor system having a display panel received in substantially a horizontal posture in a storage case, the display panel being projected out of an open front end of the storage case and being rotated upward to a raised posture when being used.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 6-64484 discloses a monitor system disposed in a console of a vehicle. This known monitor system has a display panel (display unit) received in substantially a horizontal posture in a storage case (fixed case). When the display panel is moved out of the storage case, the forward movement is transformed into the upward rotation of the display panel about the lower end thereof, so that the display panel is raised. On the other hand, when the display panel is moved into the storage case, the backward movement is transformed into the downward rotation of the display panel about the lower end thereof, so that the display panel is lowered to substantially the horizontal posture and is then received in the storage case.
The upward rotating and downward rotating mechanisms of the display panel in the known monitor system will be described below.
A movable bracket (support member) for rotatably supporting the lower end of the display panel is movably arranged in the fixed case (storage case). Points at which both sides of the lower end of the display panel are supported by the movable bracket will be referred to as first supporting points. The first supporting points are slidably engaged with raising guide portions formed in the fixed case along the length thereof, thus guiding the display panel. In addition, link members (arm members) are provided such that a second supporting point at one end of each link member is rotatably connected to the display panel in a predetermined portion on the side surface of the display panel and a third supporting point at the other end of each link member is slidably engaged with the corresponding restricting guide portion formed in the fixed case along the length thereof.
When the movable bracket supporting the display panel in substantially the horizontal posture is moved forward to move the display panel forward, the third supporting points of the respective link members are guided through the restricting guide portions and are then locked at the ends of the portions. Thus, the forward movement of each link member is stopped. In this state, when the movable bracket is further moved forward, the first supporting points for supporting the display panel are moved through the raising guide portions, so that each restricted link member pivots upward about the third supporting point by the moving force of the first supporting point. The upward pivoting of the link members about the third supporting points upwardly moves the second supporting points, at which the link members are connected to the display panel. Consequently, the lower end of the display panel is moved forward in response to the forward movement of the first supporting points, thus raising the display panel. When the first supporting points, i.e., the lower end of the display panel is further moved forward beyond a position below the second supporting points, the display panel is rotated about the second supporting points. Thus, the display panel is brought into a raised posture such that the display panel can be used.
In the state where the display panel is held in the raised posture, when the movable bracket is moved backward to backwardly move the first supporting points at which the movable bracket supports the display panel, the display panel is rotated downward about the second supporting points in the direction opposite to that in the above-mentioned operation. In addition, each link member also pivots downward about the third supporting point. Consequently, the display panel is brought into substantially the horizontal posture. When the movable bracket is further moved backward, the third supporting points and the restricting guide portions are released from their locked state. Thus, the display panel held in substantially the horizontal posture is received in the fixed case in response to the backward movement of the bracket.
In the above-mentioned monitor system, the display panel can be moved forward, raised, lowered, and moved backward by moving the movable bracket forward and backward (i.e., by a single driving source).
In the above-mentioned monitor system, the link members are pivoted upward about the respective third supporting points at one end thereof to raise the display panel that is rotatably supported at the second supporting points at the other end of the respective link members. Disadvantageously, when the distance between each third supporting point and the corresponding first supporting point, where a force is exerted in the horizontal direction, at the lower end of the display panel is reduced in the thickness direction of the display panel, a large force is required to raise the display panel. In other words, it is necessary to increase a driving force to be generated from the driving source for moving the movable bracket forward or backward.
On the other hand, to reduce the driving force to be generated from the driving source, the distance between each third supporting point, serving as a pivot of each link member, and the corresponding first supporting point at the lower end of the display panel has to be long in the thickness direction of the display panel. Disadvantageously, the thickness of the system is increased because the distance between the pivot of each link member and the lower end of the display panel has to be long.