The present invention provides an improved rHBsAg that exhibits a higher antigenicity and immunogenicity than that previously known in the art. A method of making the improved rHBsAg is also provided. The improved HBsAg is used to provide vaccines with lower amounts of active ingredient, vaccines with higher immunogenicity and combination vaccines which produce and protective immunization against infection by hepatitis B virus and other infectious agents.

The major surface antigen of the hepatitis B virus is a 25 kDa protein, HBsAg. The protein is known in three forms: preS1, preS2 and S. The preS1 and preS2 forms include 14 and 39 amino acids that are cleaved from their N-termini in vivo to yield the 226 amino acid S form. (Valenzuela P., et al. (1979) Nature, 280:815; Valenzuela P., et al., Synthesis and assembly of hepatitis B virus surface antigen particles in yeast. Nature. (1982) 298:347–350. Miyanohara A., et al., Expression of hepatitis B surface antigen gene in yeast. PNAS U S A (1983) 80(1):1–5)
Over the past two decades, recombinant hepatitis B surface antigen expressed as the S form in yeast cells (rHBsAg) has superseded plasma-derived antigen as a vaccine against hepatitis B infection (Valenzuela et al., 1982; McAleer et al., 1984). In the plasma of infected animals, the surface antigen protein assembles into 22 nm particles comprising lipids and HBsAg. However, the assembly of the yeast produced rHBsAg into these virus-like particles has remained poorly understood.
It has been established that reduction of the disulfide bonds in HBsAg abolishes or greatly decreases both its antigenic and immunogenic properties (Reviewed by Tiollais et al., 1981, Guesser et al., 1988; Mishiro et al., 1980; Chen et al, 1996; Hauser, et al 1988). For example, eleven out of the total 14 cysteine residues are conserved among three different type of S protein of Hepatitis B viruses, namely, HBsAg of human, woodchuck, and ground squirrel viruses. However, these three types of S protein share only medium to low overall sequence homology among (Stirk et al, 1992). Interestingly, all 8 cysteine residues in the"a" determinant loop (62 aa between predicted Helix B and Helix C) are fully conserved. This indicates that disulfide bonds may have an important role in maintaining the structural integrity of the antigenic determinants or epitopes (Stirk et al., 1992).
The importance of the presence of disulfide bonds to the functional and structural integrity of proteins has been well documented, particularly for ribonuclease A (Ubuka T., (1996) Protein disulfide isomerase-catalyzed renaturation of ribonuclease A modified by S-thiolation with glutathione and cysteine. Biochem Mol Biol Int. 38(6):1103–10; Fahey, R. C., (1977) Biologically important thiol-disulfide reactions and the role of cyst(e)ine in proteins: an evolutionary perspective. Adv Exp Med Biol. 86A:1–30; Lyles M M, et al., (1991) Catalysis of the oxidative folding of ribonuclease A by protein disulfide isomerase: dependence of the rate on the composition of the redox buffer. Biochemistry. 22;30(3):613–9).
In the case of rHBsAg, the correct disulfide bond pairings are important antigenic determining factors since they are most likely required for the integrity and stability of the major epitopes. (Wampler et al., 1985). Multiple chemical forms of hepatitis B surface antigen. Proc. Nat. Acad Sci. 82:6830–6834. On over-expression in yeast cells, it is believed that the HBsAg molecules need to find a lipid environment for folding into the membrane-embedded structures as seen in the plasma-derived 22 nm lipid/protein particles. However, because of a lack of the control of the cellular redox environments, unlike the propagation of the virus in the infected cells, during over-expression, and sub-optimal conditions during purification and formulation of rHBsAg, the recombinant proteins are expected to assume certain sub-optimal conformations as a result of mismatched disulfide bond pairings.
Although some cysteine-rich proteins or peptides are reported to have strong propensity to form the correct disulfide bond pairings during oxidative refolding (Moroder et al., 1996; Mosiol et al., 1994), productive folding is always in competition with nonproductive folding. These latter pathways lead to either wrong disulfide bond pairings or aggregation of polypeptides.
The rate and yield of oxidative renaturation of small reduced polypeptides have been reported to be influenced by the ratio of low molecular weight disulfide/thiol compounds. The relationships are rather complex and do not parallel the redox potential of the system, as reported using reduced RNAse A as a model protein (Wetlaufer et al., 1987).
It is reported that a redox buffer with both forms of glutathione, i.e., GSSG/GSH mixture, might facilitate the conformational searching by promoting the formation of the correct pairings and unlocking the mismatched ones. However, the use of GSSG/GSH mixtures was only demonstrated for some small proteins and peptides (Moroder, et al., 1996).
It is believed that in a natural system of cells infected by HBV, the nascent HBsAg molecules need to find a lipid environment for the formation of certain intramolecular and/or intermolecular disulfide bonds that lead to proper folding into the native conformation of the protein. In the natural system, this process leads to the formation of particles of approximately 22 nm in diameter made up predominantly of HBsAg protein associated with a lipid membrane. Similarly, when expressed in yeast cells or other expression host, it is believed that the nascent rHBsAg needs to find a lipid environment prior to the spontaneous folding into membrane-embedded structures.
However, in recombinant processes, the rHBsAg is over-expressed in a non-natural system using a host cell. Insect, yeast and CHO cells are commonly used although other cell types may be employed. When overproduced in such a system, the rHBsAg is an assortment of aggregations of scrambled forms and non-native conformations due to mismatched disulfide bond pairings. These artifacts of over-expression yield molecules locked into conformations of low antigenicity. Therefore, once produced, the over-expressed rHBsAg is typically processed outside a cellular environment to eliminate some of the undesired artifacts of over-expression.
In a method presently used in the art, once the over-expressed rHBsAg is purified from the host cells, the antigen is treated with thiocyanate in an oxidative step to induce a conformational search and yield the form of rHBsAg known as Form III (Wampler, et al., 1985) (See FIG. 1). Thereafter, formalin treatment is used to lock the rHBsAg into whatever conformation it has assumed under the chaotropic, partially denaturing conditions of the thiocyanate treatment. Finally, the rHBsAg it is precipitated with adjuvant.
Previous studies reported that one could achieve an enhancement of antigenicity of rHBsAg by incubation at elevated temperatures as well as the inhibitory effect of formalin to the same process. Moreover, the role of the different disulfides being generated (i.e., intra- and intermolecular) was also described (Wampler, et al., (1985)). In these studies, the conformational search for the thermodynamically most stable forms of rHBsAg occurred spontaneously. Therefore, the optimal percentage of correct three-dimensional structures of the rHBsAg could not be obtained by those methods. Most importantly, the reported procedures yield product that varies for potency as well as consistency. This is possibly due to the poorly-controlled redox conditions, residual metals and surface contacts during process and formulation. Thus, vaccines including rHBsAg made by previously reported methods varies considerably in amount of protein required to induce a protective response in a vaccinated subject.


A pulling grip assembly and methods, systems, and apparatuses for constructing the pulling grip assembly are disclosed. The pulling grip assembly can include a pulling grip. The pulling grip can include an elongated body portion and a lug portion. The lug portion can include a blind hole for receiving an assembly including a hollow fastening member and a pulling cable retained within the hollow fastening member.

Multiple conductor cabling consisting of multiple, independent wires or conductors are an integral part of many systems, including electrical and power systems. Such cabling may be installed by pulling the independent conductors in parallel through pipe or conduit over long distances. A pulling rope running through the conduit is attached to each conductor, and the pulling rope is pulled through the conduit, drawing the multiple conductor cabling from spools or other delivery mechanisms and through the conduit. The amount of force required to pull several conductors through a lengthy conduit, potentially with many bends or turns, may be substantial, and if the force is applied to the cabling improperly, one or more conductors may be damaged during the pull. Such damage may hamper performance of the multiple conductor cabling or present safety issues. In addition, finding and repairing the damaged portions of the conductors may be prohibitively expensive or physically impossible, and may necessitate replacement of the entire cabling.
The conductors may be attached to the pulling rope through a pulling grip assembly. The pulling grip assembly may include a pulling grip attached to each conductor and a pulling cable or lanyard that attaches each pulling grip to the pulling rope. Typically, the pulling grip has a first end and a second end and defines an interior cylindrical cavity into which a conductor may be inserted, via the first end, for attaching the pulling grip to the conductor. The second end of the pulling grip may define an aperture that the pulling cable or lanyard can be passed through for attachment to the pulling grip. Based on this construction, any moisture or debris that the pulling grip encounters can gain access to the interior cylindrical cavity of the pulling grip, via the aperture of the pulling grip, and ultimately the conductor on which the pulling grip is attached, causing damage and capacitive alterations to the conductor.


The invention provides an LED package and a backlight device incorporating the LED lens. The LED package has a bottom surface and a light exiting surface cylindrically extended around a central axis of the package from the bottom surface. Also, a reflecting surface is positioned on an opposite side of the bottom surface and symmetrical around the central axis such that light incident from the bottom surface is reflected toward the light exiting surface. Further, a scattering area is formed on the reflecting surface. According to the invention, by applying scattering materials on the reflecting surface of the LED package, a reflecting paper does not need to be attached, thereby simplifying a process and reducing the manufacture time and cost.

1. Field of the Invention
The present invention relates to a light-emitting diode (LED) package for a backlight device. More particularly, the present invention relates to a side-emitting LED package having scattering material applied on a reflecting surface, and a backlight device incorporating the LED lens.
2. Description of the Related Art
Applications using a light emitting diode (LED) as a light source are found in an LCD backlight device (system), a lighting device and the like. Also, in broader applications, an optical package may be employed in the LED to further enhance its efficiency and functions.
FIG. 1 shows an example of an LED package for an LCD backlight device.
The LED package of FIG. 1 is a side-emitting LED package 10 comprising a bottom surface 12, a side surface 14 and a funnel-shaped reflecting surface 16. An LED chip 18 is disposed inside the package 10 and the bottom surface 12 of the package 10 is supported by a mount 20 such as a printed circuit board.
The reflecting surface 16 is symmetrical around an axis A such that light generated in the chip 18 is reflected toward the side surface 14. In addition, the center of the LED chip 18 is placed on the axis A. As denoted by reference numeral L1 of FIG. 1, this allows a majority of light generated in the LED chip 18 to be emitted outward through the side surface 14.
However, some portions of light L2, L3 generated in the LED 18 are first reflected from the side surface 14, and then exit upward from the package 10 trough the reflecting surface 16. Alternatively, the light L2, L3 passes through the reflecting surface 16 along the axis line A to exit upward. Also, light L3 generated on an edge of the LED chip is emitted upward from the package through a central portion of the reflecting surface 16.
The light emitted upward radiates in a narrow and strong band. Thus without eliminating it, the LED package 10 is hardly adopted in the LCD backlight device or indirect lighting.
Therefore, to overcome this problem, as shown in FIG. 2, a reflector or reflecting paper 30 is attached to the LED package 10.
The reflecting paper 30 is attached to a top of the LED package 10 to reflect light exiting upward. Light L1, L2 reflected by the reflecting paper 30 enters inside of the LED package 10 again or disappears between a reflecting surface 16 and the reflecting paper 30, or inside the package. This completely blocks light from exiting upward from the package 10, and easily ensures the light to be emitted sideward.
At this time, a bonding section B between the package 10 and reflecting paper 30 is formed on the top of the reflecting surface 18 so that it has a narrow bonding area and thus a weak bonding force. Therefore, for smooth and secure bonding, the package 10 needs to be reconstructed partially. Meanwhile, such reflecting paper attached may lead to undesired reflection of light L3.
To attach the reflecting paper is a delicate manual job that can be hardly automated, thus increasing the manufacture time and cost for the backlight device. Moreover, the reflecting paper attached easily falls off, undermining reliability of the backlight device.
Problems arise when the structure of FIG. 2 is applied to the backlight device. An explanation thereof will be given hereunder with reference to FIG. 3.
As shown in FIG. 3, a direct-type backlight device 40 comprises a flat reflecting plate 42, side-emitting LED packages 10 as described in FIGS. 1 and 2 installed on the reflecting plate 42, reflectors or reflecting papers 30 disposed on the LED packages 10 as stated with reference to FIG. 2, a transparent plate 44 positioned at a predetermined distance G1 from the reflecting papers 30 and a diffuser plate 46 positioned at a predetermined distance G2 from the transparent plate 44.
The LED package 10 generally emits light L1, L2 sideward. The light L1 emitted is reflected from the reflecting plate 42, and passes through the above-disposed transparent plate 44. Thereafter, the light L1 is diffused at a desired uniform intensity in the above-disposed diffuser plate 46 and provides a backlight to a liquid crystal panel 48 disposed above. Another light L2 strikes a bottom of the transparent plate 44 and some portions of the light L21 enter the transparent plate 44 and provide a backlight to the liquid crystal panel 48 through the above-disposed diffuser plate 46.
Meanwhile, other portions of the light L22 are reflected from the transparent plate 44 to the reflecting plate 42 and then reflected onto the reflecting plate 42. Then the light L22 provides a backlight to the liquid panel 48 through the transparent plate 44 and diffuser plate 46 in the same manner as the light L1 does.
The backlight device 40 of this structure enables an array of LED packages 10 to be installed below the liquid panel 48, advantageously ensuring an efficient supply of a backlight to a large-sized LCD.
However, a predetermined distance G1 is required between the LED package 10 and the transparent plate 44 and also a predetermined distance G2 should be kept between the transparent plate 44 and the diffuser plate 46. Disadvantageously, this increases a thickness of the backlight device 40 of this structure.
Specifically speaking, light L generated in the LED package 10 is generally reflected upward through between the reflecting papers 30, thus forming dark areas DA shaded by the reflecting papers 30 on the transparent plate 44. To eliminate the dark areas DA and resultant bright lines, a predetermined distance G2 or more should be sufficiently maintained between the transparent plate 44 and the diffuser plate 46 so that lights mix together until before passing through the transparent plate 44 and entering the diffuser plate 46.
As described above, to ensure light traveling from the reflecting plate 32 to the liquid crystal panel 48 to radiate at a uniform intensity, such predetermined distances G1, G2 or more should be maintained, which however necessitates an increase in a thickness of the direct-type backlight device 40.

Side-emitting LED package having scattering area and backlight apparatus incorporating the LED lens


Provided herein is a fluidic cartridge having a body comprising a malleable material and a layer comprising a deformable material bonded to a surface of the body that seals one or more fluidic channels that communicate with one or more valve bodies formed in a surface of the body. The valve can be closed by applying pressure to the deformable material sufficient to crush and close off a fluidic channel in the body. Also provided are a cartridge interface configured to engage the cartridge. Also provided is a system including a cartridge interface and methods of using the cartridge and system.

Versions of systems including sample cartridges and fluidic systems for sample extraction and analysis are described in, for example, U.S. Pat. Nos. 6,190,616; 6,551,839; 6,870,185; 7,244,961; 8,394,642 and 8,431,340; US patent applications 2006/0073484; 2009/0253181; 2011/0039303; 2011/0126911; 2012/0181460; 2013/0139895 and 2013/0115607; and International Patent Applications PCT/US2013/130910 and PCT/EP2012/001413.
US patent publication 2003/0197139 refers to a valve for use in microfluidic structures.
US patent publication 2009/0314970 refers to a mechanically-actuated microfluidic pinch valve.
US patent publication 2013/0240140 refers to a process for producing a microfluidic apparatus and related laminating devices.
International publication WO 2012/136333 refers to a heat weldable film for labeling plastic polymeric reaction tubes.
U.S. Pat. No. 6,883,774 refers to a microvalve and method of forming a microvalve.
U.S. Pat. No. 7,318,912 refers to microfluidic systems and methods for combining discreet fluid volumes.
U.S. Pat. No. 8,313,941 refers to integrated microfluidic control employing programmable tactile actuators.
U.S. Pat. No. 8,501,305 refers to a laminate.


An upside-down image, generated when a video camera is rotated about a horizontal axis to face to substantially the same direction as a display unit does, is electrically corrected to be an upright image. A video camera unit made compact to realize a reduction in weight of a video camera rotating mechanism. An image arrangement convertor circuit is provided between the video camera unit and a liquid crystal display serving as a display unit or a recording unit. A switch is provided in a housing for detecting an angular position of the video camera unit. The video camera, which has an imager device and a lens, is pivoted on an edge of the housing for rotation about an axis parallel to the edge. The image arrangement convertor circuit is operated unitarily in accordance with an angular position of the video camera to automatically correct an upside-down image to an upright image. Since the video camera unit is composed of minimally necessary parts and is rotatably pivoted on an edge of the housing, a rotatable joining portion of the video camera unit with the housing can be reduced in size and weight. This structure also allows the user to adjust the angle of the video camera unit only with the thumb and index finger.

The present invention relates to a portable imager apparatus which includes a video camera as an imager unit, a direct-view type flat display as an electronic view finder or display, and a semiconductor memory or video tape recorder (VTR) as a storage or recording unit, wherein the video camera, the flat display, and the recording unit are integrated with each other, and more particularly to an imager apparatus which allows a user to monitor an image on a flat display to adjust the angle of the video camera apparatus while imaging a subject.
Conventionally, an imager apparatus of this kind has been disclosed in JP-B-4-6154 entitled "Camera Integrated VTR Having Monitor TV". This camera integrated VTR has a VTR unit and a monitor TV unit integrally accommodated in a housing, with a video camera unit pivoted substantially in a central portion of the right side surface of the housing for rotation about a horizontal axis forming a right angle with the side plane. The camera integrated VTR may be entirely supported by the right hand of a user, or the housing may be supported by the left hand such that the monitor unit opposes the user while the video camera unit is held and rotated by the right hand relative to the monitor unit to change an inclined angle of the video camera unit for imaging a subject. Also, an article "High Image Quality MS Movie VL-HL1" by Etsuo Hoshikawa et al. (Sharp Technical Report Vol. 54, No. 11 pp. 67-70, 1992) describes an imager apparatus which has a VTR and a liquid crystal display integrated on the left side of a housing such that they are pivoted for rotation relative to each other.
The kind of imager apparatus as mentioned above is structured such that the video camera unit may be rotated by an angular distance of 180 to face to the same direction as the monitor unit does. This mechanism allows the user to image himself while viewing his image on the monitor unit. Generally, the video camera is set to obtain an upright image without topsy-turvy when a subject in front of the user is to be imaged. Therefore, if the video camera is rotated by 180 about the horizontal axis, an image is displayed or recorded in an upside-down state. In order to correct such an upside-down image of the user himself to an upright image for recording, the video camera unit is first directed to the user, and then the monitor unit is rotated by 180 about the horizontal axis to face to the user. In this event, since the image would be displayed upside down on the monitor unit if the vertical scanning was started from the uppermost left position on the screen of the monitor unit as is the case of normal imaging, the vertical scanning is inverted, i.e., started from the lowermost right position of the screen to turn over the display on the monitor unit, and consequently an upright image is produced on the monitor unit.
Since the vertical scanning of the monitor unit is performed from the lowermost line instead of the uppermost line of the screen, upright images are usually displayed on the screen when the video camera unit and the monitor unit face to the same direction. Stated another way, even if the video camera unit is normally held with the monitor unit rotated by 180 about the horizontal axis, upright images are displayed on the monitor unit. On the contrary, even if the monitor unit is normally held with the video camera unit rotated by 180 about the horizontal axis, upright images are displayed on the monitor unit. In summary, upright images are usually displayed on the monitor unit even when either the video camera unit or the monitor unit is turned over. In view of recording images by a recording apparatus such as VTR, it is correct to normally hold the video camera unit and turn the monitor unit over. However, it is often the case that, during imaging, the user holds the monitor unit at a constant angle (the screen of the monitor unit generally faces the user) and changes the angle of the video camera unit to follow a subject. Therefore, even when the user images himself, the user often rotates the video camera unit by 180 with the monitor unit left at a fixed position, considering that the same imaging way also applies in this case. As a result, upside down images are recorded on a recording medium by a recording apparatus.
Also, in the prior art examples described in JP-B-4-6154 and Hoshikawa's article, the imager apparatus is such a type that the user holds the video camera unit for imaging, where the video camera unit has a size equal to or close to that of the VTR unit or the monitor unit, and the VTR unit and the monitor unit are rotatably pivoted in the video camera unit. On page 70 of the Hoshikawa's article, a rotating member is disclosed for coupling the video camera unit and the VTR liquid crystal monitor unit. Since the rather heavy VTR unit and monitor unit are rotatably pivoted in the large video camera unit, joining portions for supporting these components require high strength, as will be also appreciated from the fact that a holder member such as a mechanism hold frame is needed. The structure for ensuring this high strength leads to a larger size and increased weight of the whole imager apparatus.

Imager apparatus with rotatable camera head


A glide head calibration technique uses two fly height calibrations on a disk media certifier. The first calibration point uses a spin down on bump technique at a first height, and the second calibration point uses a spin down on disk media roughness at a second lower height. With two height data points, a fly height curve of each glide head is approximated very accurately. Once the fly height curve is derived for each head, any fly height can be dialed-in by the disk media certifier for glide testing. This technique achieves glide fly heights between about 4 nm and 8 nm and does so with improved tolerances.

1. Technical Field
The present invention relates in general to improved calibration of glide heads and, in particular, to an improved system, method, and apparatus for measuring media roughness and combining that with spin down calibration to form a new and improved glide head calibration for media glide testing.
2. Description of the Related Art
Data access and storage systems comprise one or more storage devices that store data on magnetic or optical storage media. For example, a magnetic storage device is known as a direct access storage device (DASD) or a hard disk drive (HDD) and includes one or more disks and a disk controller to manage local operations concerning the disks. The hard disks themselves are usually made of aluminum alloy or a mixture of glass and ceramic, and are covered with a magnetic coating. Typically, two or three disks are stacked vertically on a common spindle that is turned by a disk drive motor at several thousand revolutions per minute (rpm).
The HDD also has an actuator assembly with an actuator that moves magnetic read/write heads to the desired location on the rotating disk so as to write information to or read data from that location. Within most HDDs, the magnetic read/write head is mounted on a slider. A slider generally serves to mechanically support the head and any electrical connections between the head and the rest of the disk drive system. The slider is aerodynamically shaped to glide over moving air in order to maintain a uniform distance from the surface of the rotating disk, thereby preventing the head from undesirably contacting the disk.
Typically, a slider is formed with an aerodynamic pattern of protrusions or air bearing design on its air bearing surface (ABS) that enables the slider to fly at a constant height close to the disk during operation of the disk drive. A slider is associated with each side of each platter and flies just over the platter's surface. Each slider is mounted on a suspension to form a head gimbal assembly (HGA). The HGA is then attached to a semi-rigid actuator arm that supports the entire head flying unit. Several semi-rigid arms may be combined to form a single movable unit having either a linear bearing or a rotary pivotal bearing system.
The head and arm assembly is linearly or pivotally moved utilizing a magnet/coil structure that is often called a voice coil motor (VCM). The stator of a VCM is mounted to a base plate or casting on which the spindle is also mounted. The base casting with its spindle, actuator VCM, and internal filtration system is then enclosed with a cover and seal assembly to ensure that no contaminants can enter and adversely affect the reliability of the slider flying over the disk. When current is fed to the motor, the VCM develops force or torque that is substantially proportional to the applied current. The arm acceleration is therefore substantially proportional to the magnitude of the current. As the read/write head approaches a desired track, a reverse polarity signal is applied to the actuator, causing the signal to act as a brake, and ideally causing the read/write head to stop directly over the desired track.
The presence of asperities on the surfaces of the disks can have a deleterious effect on the performance of disk drives. For this reason, a glide test is performed on finished disks to detect asperities that might contact the magnetic head flying at its normal height in a disk drive. In the test, a special glide head containing a piezoelectric transducer (PZT) is flown over a disk at an altitude or height that is below the normal drive fly height. Glide head contact with an asperity creates a PZT voltage response that generally scales with increasing size of the asperity. If the voltage response exceeds a predetermined level, the disk is rejected. As such, quantitative glide testing requires calibration of the voltage response with respect to asperity height.
In the prior art, there are a number of methods for calibrating glide head fly heights. One method of calibrating glide heads uses a laser-generated, nano-sized protrusion or bump on the surface of a disk that can serve as a calibration asperity. Laser nano-bump generation is a technique that is used throughout the data storage industry. Flying a glide head over a laser nano-bump whose height is known (e.g., by interference or atomic force microscopy) will thus generate a calibrated PZT response. However, when using a single laser calibration bump, statistical variation in the PZT signal from one run to another results in a wide response distribution.
In another method, the glide head is spun down onto bumps with a known average height arrayed around one or more tracks on a disk media. When the glide head touches the top of the bumps, that linear velocity is used to set the glide test at the average height of the bumps. This "spin down to bump" calibration methodology can only support bump heights down to about 8 nm. The laser melt process used to generate the bump disk media has difficulties maintaining bump height accuracies below 8 nm. However, present and future performance requirements need glide head fly heights down to about 4 nm.
One solution to this problem is to spin down onto the disk media with a substrate roughness that is very near the desired low fly height. Fortunately, most glass substrate roughness is in the range of about 3 to 4 nm. Substrate texturing techniques can generate spin down response up to about 7 nm. However, this solution alone has some deficiencies. A good glide head calibration technique should do more than just (a) set the right fly height for glide testing. The technique should also check each glide head for (b) proper flying characteristics and (c) uniform PZT response. Thus, since parameters (b) and (c) are not provided, the glide head PZT signal generated by spinning down onto the media roughness does not hold enough information to satisfy the requirements of a good calibration technique.
A second problem with spinning down onto disk media roughness is that the current glide PZT channel has problems handling the PZT response of the glide head flying at the media roughness height. Typical glide channels were designed to analyze glide heads hitting discreet media defects producing PZT signals with very fast rise and decay times. These transitions in the PZT signal trigger software interrupts allowing each discreet hit to be counted. The PZT signal of a glide head on media roughness can resemble a DC phenomena shift from low to high and stay high due to the many contacts around the track. When this happens, one cannot determine if the glide head is hitting one discreet defect or many contacts due to the media roughness.
The PZT RMS signal could be used to measure the disk media roughness with spin down. However, one significant weakness of RMS is that a single defect with sufficient amplitude can greatly affect the RMS reading of the entire track and thereby render useless any information gleaned therefrom. Thus, an improved system, method, and apparatus for glide head calibration at lower fly heights would be desirable.

System, method, and apparatus for glide head calibration with enhanced PZT channel for very low qualification glide heights

Hitachi Global Storage Technologies Netherlands B.V.


A learning apparatus for use with a computer comprising a set of tactile flash cards, each individual card having a tactilely perceptible pattern embossed on a surface of the card and two electrically connected contacts at a unique set of discrete spaced positions on the card with a preselected correspondence between the tactilely perceptible pattern on the surface of the card and the selected positions of the contacts, and a tactile flash card reader capable of sensing the positions of the contacts on a card and controlling the computer.

Braille is a tactile system using raised dots to represent the letters of the alphabet, numerals, punctuation marks, or musical notes for persons with severe visual impairment. Each letter of the alphabet, numeral, punctuation mark, or musical note is formed from raised dots arranged within a cell (a "braille cell") having three rows and two columns. Braille is read by moving the fingers gently over the surface which has been embossed with the braille dots.
There are many available devices to aid persons who know braille in using braille, but few devices to help the blind and those with failing vision to learn braille. This is unfortunate, as braille literacy can expand the world for persons having severe visual impairment.
Typically braille is taught by a teacher working with one student at a time. The teacher may present material written in braille to the student, who then attempts to read it correctly. The teacher is available to provide feedback as to the correctness of the student's reading of the braille. Self-study is difficult for a blind person as immediate feedback is normally not possible. The blind student cannot easily check his or her work.
The prior art of which the inventor is aware includes braille learning aids that use tactile flash cards with embedded magnetic tape read in a manner similar to that used in an audio tape player. For example, in Schloss, U.S. Pat. No. 4,027,405, a tape read head is moved past a length of magnetic tape embedded in a tactile flash card. To hear the letter or word corresponding to the braille embossed on the face of the card spoken the student places the card on the reader. The tape read head then moves past the embedded tape picking up the recording of the material corresponding to the braille. Devices such as that disclosed in Schloss contain moving parts and hence would be susceptible to damage by young students learning on their own.
An apparatus for learning braille capable of being operated independently by a person having little or no vision is highly desirable, particularly for unaided home study. Such an apparatus should be simple to use (for example, requiring minimal or no computer operating or keyboarding skills) and either be inexpensive or use readily available technology such as a personal computer with a sound card. Further, such an apparatus should be flexible enough to allow easy revision of both (1) the particular braille characters, words, or sentences being taught and (2) the voice reading the braille to be changed to either another person's voice or to a sound. For example, the word "bird" might be spoken and the sound of a bird played when a card having the braille for "bird" is read by the system.


Systems are provided for a modular multi-wavelength UV-VIS detector unit, such as an absorbance detector (e.g., spectrophotometer) included in a high-performance liquid chromatography system. In one example, a detector unit includes one or more light emitters and a sliding assembly configured to slidingly move a flow cell relative to the one or more light emitters, the one or more light emitters mounted on a floating rig to facilitate alignment between the one or more light emitters and the flow cell when the sliding assembly is in a closed position.

Spectrophotometers quantitatively measure the light reflection or transmission properties of a material as a function of wavelength. UV-VIS spectrophotometers, which utilize light in the ultraviolet (UV) and visible (VIS) regions of the electromagnetic spectrum, are commonly used to detect and identify analytes in liquid samples. For example, UV-VIS spectrophotometers (e.g., absorbance detectors) may be included as detectors in liquid chromatography systems, such as high-performance liquid chromatography (HPLC), two-dimensional chromatography, ion chromatography, and ultra-high pressure liquid chromatography (UHPLC) systems. An HPLC system may use one or more pumps to flow a pressurized liquid solvent (also termed "mobile phase") containing a sample mixture through a column filled with a solid adsorbent material (also termed "solid phase"). Each component (e.g., analyte) in the sample mixture interacts with mobile phase and the solid phase differently based on their chemical compositions and structures; components with a higher affinity for the mobile phase will flow through the column more quickly, whereas components with a higher affinity for the solid phase will flow through the column more slowly. The different flow rates of the different components enable components of a complex mixture to be purified, for example. In another example, a specific component may be identified based on an amount of time it remains on the column (e.g., retention time). After each component is eluted from the column, the respective component may flow through the detector (e.g., UV-VIS spectrophotometer).
While flowing through a flow cell of the UV-VIS spectrophotometer, each component is exposed to one or more wavelengths of light emitted from one or more light sources (e.g., deuterium lamps, mercury arc lamps, tungsten lamps, light-emitting diodes, and/or laser diodes). The light may be partially to fully absorbed by the component depending on the chemical structure and concentration of the component as well as the wavelength(s) of light used. Any unabsorbed light may pass through the flow cell and be transmitted to a signal detector (e.g., a variable-wavelength detector system or a diode array detector system).
In particular, deuterium lamps, mercury arc lamps, and tungsten lamps are relatively large compared to a typical flow cell of the UV-VIS spectrophotometer. Additionally, the light emitted from these light sources is spatially and spectrally broad, thus requiring optical conditioning. These light sources also have to be pre-warmed before use and typically have a limited life (for example, tungsten lamps has to be replaced after ˜2000 hours of use), increasing both the time and the cost of operation of the HPLC system. Therefore, light-emitting diodes (LEDs) are often used for a longer-lasting, smaller, and more cost-effective light source that does not require pre-warming before use.
However, unlike the spectrally broad lamps mentioned above, each LED emits a different wavelength of light. Therefore, the ability of the UV-VIS spectrophotometer to detect a particular analyte may be limited based on the spectral characteristics of the analyte and the configuration of the UV-VIS spectrophotometer (e.g., the emission wavelengths of the included LEDs). The detection needs of a user may change over time. As a result, the user may purchase additional, expensive equipment, such as a second HPLC system or a second UV-VIS spectrophotometer, in order to detect components with spectral characteristics outside of those detectable by a first UV-VIS spectrophotometer. In other examples, a service technician may upgrade the first UV-VIS spectrophotometer, such as by disassembling the first UV-VIS spectrophotometer and installing new components.
The inventors herein have recognized the above-mentioned issues and have engineered a way to at least partially address them. In one example, the issues described above may be addressed by a detector unit for an analyzer. The detector unit may include one or more light emitters and a sliding assembly configured to slidingly move a flow cell relative to the one or more light emitters, the one or more light emitters mounted on a floating rig to facilitate alignment between the one or more light emitters and the flow cell when the sliding assembly is in a closed position.
The above advantages and other advantages and features of the present description will be readily apparent from the following detailed description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

Systems for a modular multi-wavelength absorbance detector


Versatility of a memory card is improved by providing a memory card where data protection mode and normal mode can be selected at discretion. A portable auxiliary storage device includes a mode setting section, a mode detecting section and a memory access control section. The mode setting section allows a user to set a normal mode permitting reading data stored in a memory section or writing the data to the memory section without restriction and a data protection mode for restricting the reading or writing. The mode detecting section detects a mode set in the mode setting section. The memory access control section controls the read or write according to a state of the mode setting section detected by the mode detecting section.

A memory card of an SD card or the like (hereinafter, simply referred to as a "memory card"), a USB memory, and the like are portable auxiliary storage devices adopting a flash memory as a recording medium. Since these are designed in a small size, electronic data may be optimally carried. For example, when a personal computer (PC) having a card slot into which the memory card can be inserted is possessed at both working place and home, it is possible to store and carry only required data in the memory card without carrying the PC from the home to the working place or from the working place to the home each time. This convenience receives a support of the markets and the number of sales is rapidly increasing.
Confidential data on business or the like is usually stored in the portable auxiliary storage device. On the other hand, it may be frequently lost due to smallness. When the portable auxiliary storage device falls into the hands of a malicious third person, there is a problem in that business data may be copied and distributed through the internet.
Recently, with the improvement of networking infrastructure, the opportunity to perform electronic commercial transaction (so-called e-commerce) through the internet is increasing. For example, a user conducts the electronic commercial transaction such as online stock trading even while traveling. The user conducts the electronic commercial transaction using a PC provided in a guest chamber of a hotel or the like or a PC permanently installed in a so-called internet cafe. Personal information (for example, a user ID or password, a bank account number, a telephone number, and the like) used for the transaction is stored and carried in the portable auxiliary storage device. When it is forgotten to extract the portable auxiliary storage device from the PC of the traveling place or the PC of the internet cafe, the third person may freely use the personal information.
As described above, the portable auxiliary storage device of the memory card or the like is convenient, but it is necessary to surely perform security protection and conventionally a countermeasure thereof is being variously considered.
For example, a technique has been disclosed for prohibiting the read of information from the memory card after a lapse of a given time by requesting a write to a dummy area of predetermined data when information is read from the memory card and providing a timer within the memory card to count the lapse of the given time from the dummy write with the timer (for example, see Patent Document 1).
[Patent Document 1] Japanese Patent Unexamined Publication No. 7-200767
A memory card described in the above-mentioned Patent Document 1 has a certain effect as an information leakage countermeasure. However, in the above-mentioned memory card, the read of information within the memory by a third person may be prohibited, but also the information read of a memory card possessor himself may be prohibited. The above-mentioned Patent Document 1 describes an indication to postpone the prohibition of the information read by reperforming a dummy write in a period shorter than a predetermined time before the lapse thereof in the timer count when the possessor knows an operation of this memory card.
However, when this dummy write is often requested to the user, the usability of the memory card is significantly damaged. This situation may be avoided by always preparing both a memory card having a data protection function and a general memory card (without a protection function), but the case where the user is requested to always prepare a plurality of memory cards is contrary to the convenience of the memory card.


A centrifugal fuel distributor including a drive shaft rotatably mounted within a housing having a distribution cavity. A sidewall of the distribution cavity defines a plurality of spaced-apart fuel outlets, and a hollow armature is biased radially outwardly from the drive shaft, so that a distal end of the armature is in sealing contact with an inner surface of the sidewall. During operation, pressurized fuel travels through a fuel passage in the drive shaft and through the hollow armature while the drive shaft is rotated, so that the distal end of the armature slides along the inner surface of the sidewall of the distribution cavity and sequentially distributes fuel to the plurality of fuel outlets. The fuel then passes from each fuel outlet to fuel injectors mounted in cylinders of an engine incorporating the fuel distributor. A timing rotor is secured to the drive shaft and signals the position of the armature as the drive shaft rotates to an actuator controlling fuel flow, so that the actuator allows the fuel passage to be replenished with pressurized fuel each time the hollow armature distribute fuel to a fuel outlet.

In conventional fuel delivery systems for internal combustion engines, a constant-delivery fuel pump supplies fuel under pressure from a tank to a fuel rail positioned on the engine. A plurality of fuel injectors are mounted between the fuel rail and the engine intake manifold, with the injector nozzles being positioned adjacent to the fuel/air intake ports of the individual engine cylinders. The fuel injectors are individually electromagnetically actuated by an engine control unit as a function of operating conditions and parameters at the engine.
A major cost associated with fuel delivery systems of the described character lies in the individual fuel injectors, and in the complexity of electrical conductors that connect the fuel injectors to the engine's electronic control unit. In addition, the fuel injectors are subject to wear, and may eventually feed differing quantities of fuel to the cylinders even when actuated for nominally identical time durations, thus resulting in less than optimum engine operation. Furthermore, conventional fuel injectors present additional difficulties when employed in conjunction with so-called alternative fuels. Fuels of this character have lower lubricity than conventional gasoline fuels, increasing wear at the individual injectors. The injector wear parts may be constructed of stainless steel to reduce wear, but this greatly increases cost. Moreover, because of lower energy content of alcohol-based alternative fuels, for example, the injectors must have a larger fuel opening and/or remain open longer than would otherwise be desirable in operation with gasoline. Thus, conventional fuel injectors are not well suited for use in association with engines intended for operation with alternative fuels having differing potential energy contents.
U.S. Pat. No. 3,664,318 to Giuffra discloses a fuel injection system not requiring conventional fuel injectors. The system includes a distributor housing fixed in a housing above a distribution cavity. A shaft is rotatably mounted in the housing and passes through the distribution cavity and the distributor housing. The distributor housing defines an aperture for each cylinder of an engine, and each aperture connects the distribution cavity with a fuel outlet of the housing. A flat, plate-like distributor rotor is secured to the shaft within the distribution cavity, blocking the apertures of the distributor housing. During operation, the distribution cavity is filled with fuel and the shaft and the distributor rotor are rotated. The distributor rotor defines a rotor aperture that sequentially aligns with each of the apertures in the distributor housing as the rotor rotates, so that fuel can pass to the fuel outlets and to fuel injectors in the engine cylinders.
One drawback of the Giuffra system is that the distributor cavity must be filled with fuel during operation before the fuel is distributed to the fuel outlets. Filling the distributor cavity, however, requires a complex fuel pumping means which adds many parts and increases the complexity of the distributor. What is desired, therefore, is a distributor that distributes fuel directly to fuel outlets without requiring that the distributor cavity be filled with fuel.


A waveguide coupling structure includes: a first section that supports a mode that has an associated first intensity profile that substantially overlaps with an intensity profile associated with a mode supported by a first waveguide portion at a first end of the waveguide coupling structure; a second section that supports a mode that has an associated second intensity profile that substantially overlaps with an intensity profile associated with a mode supported by a second waveguide portion at a second end of the waveguide coupling structure; and a third section, between the first section and the second section, comprising a core structure on a bottom cladding and a supporting structure on the bottom cladding. The supporting structure: (1) overlaps with at least a portion of an intensity profile associated with a guided mode of the third section, and (2) has a shape that is asymmetric with respect to a propagation axis of the guided mode in a plane parallel to a surface of the bottom cladding.

A waveguide is a physical structure that confines and guides the propagation of an electromagnetic wave. Some electromagnetic waves have a spectrum that has a peak wavelength that falls in a particular range of optical wavelengths (e.g., between about 100 nm to about 1 mm, or some subrange thereof), also referred to as optical waves. Photonic integrated circuits (PICs) often include optical waveguides for transporting optical waves around a device and into and out of optical elements (e.g., splitters, modulators, interferometers, resonators, multimode interference (MMI) couplers, etc.). These optical waveguides may be implemented, for example, by forming a core structure from a material having a higher refractive index (e.g., silicon, or silicon nitride) surrounded by a cladding (also called a "buffer") comprising one or more materials (or air) that have a lower refractive index, such as a buried oxide layer (e.g., silicon dioxide) of a substrate, such as a silicon-on-insulator (SOI) wafer. The cladding may in some cases surround the core structure, and may be formed by a single lower-index material, or by multiple different lower-index materials, which may include air if a core material is deposited on top of a cladding material without another material being deposited on top of the core material.
A variety of different types of structures having different geometries can be used to form waveguides in such PICs. For example, a ridge waveguide may refer to a waveguide that has a rectangular (cross-section) core structure on a lower-index cladding. A rib waveguide may refer to a waveguide that has a rectangular core structure having a particular height above the cladding, and lower-height slabs on either side of the rectangular core structure and composed of the same material as the rectangular core structure. These and other waveguide structures can support multiple modes of an optical wave being guided by the waveguide. A mode has an associated spatial distribution of an electromagnetic field intensity in a plane perpendicular to the propagation direction in the waveguide. A mode also has an associated polarization for the electric and magnetic fields of the electromagnetic wave. Some modes can be characterized as transverse electric (TE) modes for which the electric field has a polarization substantially perpendicular to the propagation direction, and some modes can be characterized as transverse magnetic (TM) modes for which the magnetic field has a polarization substantially perpendicular to the direction of propagation. In some cases, modes may be characterized as having hybrid polarization, which is not strictly a TE or TM mode, or has a substantially transverse electric or magnetic field that may not be perfectly perpendicular to the direction of propagation and thus is a substantially TE or substantially TM mode.

Managing mode transfer in asymmetric waveguide coupling structures


A fuel cell system has an improved connector assembly to provide for the quick connection of a fuel cartridge and the fuel cell. Two leak resistant connector members with an easy to engage coupling mechanism that stably grips the two connector members to provide for flow between the members. The first connector member is adapted to engage the second connector member to form a unitary structure, which can establish fluid communication between the connector members. Generally, both the first connector member and the second connector member comprise a fluid flow path that can be each sealed/unsealed by a poppet valve or other suitable valve members. In some embodiments, the connector members can be engaged/disengaged by rotating an element of the coupling mechanism. The connector assemblies can be particularly useful for the connection of a fuel cell with a fuel cartridge.

In general, a fuel cell is an electrochemical device that can convent energy stored in fuels such as hydrogen, methane, methanol and the like, into electricity without combustion of the fuel. A fuel cell generally comprises a negative electrode, a positive electrode, and a separator within an appropriate container. Fuel cells operate by utilizing chemical reactions that occur at each electrode. In general, electrons are generated at one electrode and flow through an external circuit to the other electrode where they are consumed. This flow of electrons creates an over-voltage between the two electrodes that can be used to drive useful work in the external circuit. In commercial embodiments, several "fuel cells" are usually arranged in series, or stacked, in order to create larger over-potentials.
A fuel cell is similar to a battery in that both generally have a positive electrode, a negative electrode and electrolytes. However, a fuel cell is different from a battery in the sense that the fuel in a fuel cell can be replaced without disassembling the cell to keep the cell operating. Additionally, fuel cells can have several advantages over other sources of power that make them attractive alternatives to traditional energy sources. Specifically, fuel cells are environmentally friendly, efficient and utilize convenient fuel sources, for example, hydrogen or methanol.
Fuel cells have potential uses in a number of commercial applications and industries. For example, fuel cells are being developed that can provide sufficient power to meet the energy demands of a single family home. In addition, prototype cars have been developed that run off of energy derived from fuel cells. Furthermore, fuel cells can be used to power portable electronic devices such as computers, phones, video projection equipment and the like. Fuel cells designed for use with portable electronic equipment provide an alternative to battery power with the ability to replace the fuel without replacing the whole cell. Additionally, fuel cells can have longer power cycles and no down time for recharging, which also makes fuel cells an attractive alternative to battery power for portable electronics.
As described above, fuel cells are becoming an increasingly attractive alternative to traditional energy sources such as batteries and fuel combustion. For example, fuel cells are currently being developed to power portable electronic devices such as, for example, laptop computers, video projection equipment and the like. It may be convenient for fuel cells designed for use with portable electronic devices to be compatible with portable and interchangeable fuel containers, which permit empty or partially empty fuel containers to be replaced in order to keep the fuel cell, and ultimately the portable electronic device, operating. In some embodiments, these fuel cells are designed to use liquid fuels such as, for example, methanol, although they can use other fluid fuels, such as compressed hydrogen or methane.
Generally, fuel containers or fuel cartridges suitable for use with portable electronic devices comprise a storage structure having a suitable fuel located therein. Additionally, these fuel containers can further comprise a passage which provides access to the interior of the container or cartridge. In some embodiments, the pass is coupled to a connector that is adapted to couple with a fuel inlet port on a portable fuel cell to establish fluid communication between the fuel cell and the fuel container once appropriate valves or other control element are opened. In one embodiment, fuel containers suitable for use with fuel cells designed for portable electronic devices can comprise a rigid outer container associated with a flexible inner container in which a fluid such as, for example, methanol is stored. In some embodiments, these types of fuel containers can further comprise a port in the outer container which allows transport of the filled inner container into the outer container. These types of fuel containers are described in, for example, commonly assigned and co-pending U.S. patent application Ser. No. 10/384,382, filed on Mar. 7, 2003, entitled "Fuel Storage Container For A Fuel Cell," which is hereby incorporated by reference herein. In addition, methanol, and other organic fluids suitable for use in fuel cell applications, are generally environmental pollutants and flammable and, therefore, can present safety and other release issues. As a result, it may be desirable to reduce the amount of potential fluid leakage during engagement of the fuel container with the fuel cell, while still maintaining the ability to quickly connect and disconnect the containers from the fuel cell.


The disclosed computer-implemented method for performing micro-segmenting may include (i) identifying at least a portion of a device, (ii) measuring a variance value that indicates a level of variance in terms of websites accessed by the portion of the device over a period of time, and (iii) locking, in response to determining that the variance value satisfies a threshold level of simplicity, the portion of the device by applying a security profile to the portion of the device that limits the portion of the device to accessing a set of websites that is defined in terms of the websites accessed by the portion of the device over the period of time. Various other methods, systems, and computer-readable media are also disclosed.

In the context of computer security systems, "micro-segmentation" is the idea of locking down a system based on what that system is legitimately expected to do. In some examples, security vendors may plan on identifying devices that have website access patterns that are simple enough that the security vendors will feel confident that restricting those devices to the previously accessed websites will enable proper use of the device while also protecting against rogue behavior in the case that the device has become infected.
Nevertheless, according to some related systems, security vendors may only feel confident in applying micro-segmentation to devices that have website access patterns that are exceptionally simple, such as a device that only visits five separate unique domains. Although these related systems may provide some benefits, the list of sites that most devices access can vary wildly and will likely change over time. This is likely true even for relatively simple devices. In addition, some security vendors may profile the behavior of each device as a whole, yet these devices may typically execute a LINUX-based operating system that is running several sub-components. The instant disclosure, therefore, identifies and addresses a need for improved systems and methods for performing micro-segmenting.

Systems and methods for performing micro-segmenting


A guide system for a door assembly including a door, which door can be attached to the guide system in a pivotal manner, has a closed position in which at least one device object can be covered on the front side and a parked position in which the door can be moved, preferably slid, in a direction transversely to the front of the at least one device object, preferably into a lateral receiving shaft, by the guide system. The guide system for the door is assembled or formed on a support structure separate from the device object to be covered, the support structure having at least one stand surface for standing on the floor of a room and/or at least one assembly device for assembling on the wall of a room.

The invention concerns a guide system for a door assembly comprising a door which can be mounted pivotably to the guide system, with a closed position in which at least one furniture item can be covered at the front side, and a parked position into which the door is moveable, preferably slidably, by means of the guide system in a direction transversely relative to a front of the at least one furniture item—preferably into a lateral receiving shaft. The invention further concerns a door arrangement comprising such a guide system and a furniture arrangement comprising such a door arrangement. Finally the invention also concerns a method of mounting a furniture arrangement.
Usually furniture carcasses are closed by pivotal doors or sliding doors. The disadvantage there is that in the opened state the doors also project into the room or in the case of sliding doors they do not allow complete opening. To counteract that there is already the proposal that the doors are firstly moved to the side and then slid into a lateral receiving shaft oriented perpendicularly to the front of the furniture carcass (for example CH 693070 A5).
In the known solution the receiving shaft is integrated in the furniture carcass. This therefore involves a special furniture carcass. In that respect there are two variants: in a first variant this involves a pivotal door which, after being pulled out of the shaft, is simply pivotable about a vertical pivot axis to close the furniture carcass. In a second variant this involves a folding door which, after being pulled out of the shaft, can be unfolded, wherein the two leaves of the folding door are pivotably connected together by way of folding door hinges. It is possible therewith to cover a relatively large front surface of a furniture carcass. Nonetheless the door can be parked in space-saving fashion in the receiving shaft (parked position).

Guide system for a door assembly, door assembly, and device assembly


The present invention is a method and apparatus for increasing the effective contrast ratio and brightness yields for digital light valve image projectors using a variable luminance control mechanism (VLCM), associated with the projector optics, for modifying the light output and providing a correction thereto. Also included is an adaptive luminance control module (ALCM) for receiving signals from the video input board, the adaptive luminance control module producing a signal on a VLCM bus connecting the variable luminance control mechanism and the adaptive luminance control module, wherein the signal causes the variable luminance control mechanism to change the luminance of the light output and provide a corrected video signal for the projector.

Heretofore, a number of patents and publications have disclosed means for controlling the intensity, contrast or dynamic range of a projection image, the relevant portions of which may be briefly summarized as follows:
U.S. Pat. No. 5,386,253 to Fielding, issued Jan. 31, 1995, and incorporated herein by reference in its entirety, discusses exemplary projection systems utilizing one or more spatial light modulators (SLMs).
U.S. Pat. No. 5,717,422 to Fergason, issued Feb. 10, 1998, discloses a display and method employing a passive light modulator, a source of light, and a control for controlling the intensity of light supplied to the light modulator to provide images of good contrast for both bright and dark scenes. A method of displaying an image, which uses a passive light modulating display apparatus, includes controlling the intensity of light illuminating the display apparatus as a function of a brightness characteristic of the image.
US-20040001184A1 by Gibbons et al., published Jan. 21, 2004 (and claiming priority from PCT/US01/21367 filed Jul. 2, 2001), teaches a system for addressing deficiencies of electronic, SLM-employing projectors. It does so using techniques described as being capable of providing images of sufficient overall quality that they may be used in venues instead of, or in addition to, traditional large-format film projectors without disturbing audience perception that the viewed images are of high quality. The publication describes techniques including pre-modulation, luminance compensation, and partial luminance compensation.
A data and/or video projector's light valve optical engine is generally a device that uses means of modulating a fixed or variable light source based on either the reflective or transmissive properties of certain imaging panels. These panels may be Liquid Crystal Display (LCD), Liquid Crystal on Silicon (LCOS & SXRD), a Digital Micromirror Device (DMD) or any other pixelized imager panel(s) system.
Most high-lumen output video projectors use an arc lamp for the illuminating source. In the case of LCD and LCOS versions of imagers the white light produced by such lamps is usually separated into the primary colors of red, green, and blue using dichroic color-separating optics. Arc lamp separated colors are then passed through a polarizing filter to work with polarizing beam splitters. The primary color beams are either passed through the LCD panels (a transmissive technology) or reflected from LCOS panels (a reflective technology). However imperfections in both the means of polarization of the beams and the inability of the imagers to completely block the illumination source results in a reduction of the contrast ratio (CR) of the image.
DMD imagers utilize non-polarized light from the illumination source, may or may not contain beam splitters and contain micro-mirrors that direct light through the lens or away from the lens as directed to form the image (another reflective technology). Primarily, diffraction & reflection of light from various planes within the DMD and less than perfect reflectivity of the mirrors themselves results in a reduction of the contrast ratio of the image.
For the purposes of this presentation optical components between the illumination source (lamp) and the outermost exit lens are considered the projector's "optical engine." Optical engines include but are not limited to dichroic beam splitters (where applicable), polarizers (where applicable), imaging panel(s), re-combining optics (where applicable), light tunnels, light collimators, irises, etc.
The present invention is directed to a method and apparatus to increase the effective contrast ratio and brightness yields for all types of data/video digital light valve image projectors. This concept is partially based on the fact that the contrast ratio dynamic from such devices displaying a "bright" image is limited to a projector's simultaneous contrast capability (commonly measured as ANSI contrast ratio—hereinafter ANSI CR), and the fact that the ON/OFF contrast ratio limits a projector's "dark" image's dynamic to a point much less than a light-valve projector's ANSI CR capability. It is also based on the fact that current light valve projectors (LCD, LCOS, SXRD, DMD) have extremely limited ON/OFF contrast ratios, when compared to standard cathode ray tube (CRT) type projectors, and are in need of this design improvement.
CRT type projectors are able to maintain, for the most part, full ANSI CR regardless of the image's general level of illumination due to the variable intensity output capability of their tubes. However, light valve projectors have a steady state of illumination source (i.e. a lamp) that is modulated solely by the imaging device(s). As such it is necessary for the imaging devices, regardless of type (DMD/LCOS//SXRD, LCD, etc) within the projector, to generate all of the image's dynamics. Since all these imaging devices "leak" light to varying degrees (i.e., areas intended to be dark or off are not completely dark), this limits the projector's ability to maintain full ANSI CR, particularly at the lower intensity levels resulting in a lack of depth in the image.
Attempts have been made in the past to vary a projector lamp's output to boost on/off CR, but these have failed to provide significant improvement due to the limited variable light output range of lamps (maintaining sustained ignition) and the fact that varying the lamp intensity drastically changes the color balance (balance in spectral output) of the lamp, thus limiting most light-valve projectors to one or two illumination levels from their bulbs (current examples: bright and economy-lamp modes). None of the lamp intensity schemes interact in concert with the imager(s) or help to produce better engine contrast ratio yield as the invention described herein does, neither do projectors with simple fixed or manually or electrically adjustable irises. The present invention relies on the technological premise that digital imaging devices perform three basic functions, among others, in order to generate a usable image for display:                1) modulate imager(s) with a source signal to create a recognizable pattern (i.e. an image);        2) set the general level of scene illumination; and        3) "paint" the image to create color(s) with a variety of available techniques.
The present invention focuses on the second function set forth above—setting the general level of scene illumination, where this function is removed, at least partially, from the duty list of the imager(s) for the primary purpose of increasing overall contrast ratio and increasing the available ANSI dynamic for low-brightness images/scenes. In order to accomplish this function outside of the typical projection optical imaging engine, one aspect of the invention is intended for implementation in two stages, which are described in more detail below.
A first component of the present invention is a variable luminance control mechanism (VLCM). The VLCM is, in one embodiment, a special high-speed, temperature-resistant, electronically controllable iris system placed before, after or inside the optical engine of any light-valve projection device. A single (or multiple in some cases) iris system will be located at the point(s) either pre- and/or post-imager(s) within the optical engine that yields the best balance of results. This location will vary from projector to projector depending upon its particular design and on the intended results. In the case of single digital light processing (DLP) chip optical engines, this calls for a single iris system placed post-imager at a focal convergence point located post imager. The purpose of this adjustable iris is to vary the general scene illumination level, as the input signal varies, at a speed that is generally undetectable to the human eye. The main benefit of the luminance control function provided by the iris is extending the ON/OFF contrast ratio well beyond the ability of the imaging devices themselves. In other words, the use of the iris improves the ON/OFF contrast ratio by lowering the scene illumination on dark scenes to a nearly completely off level and thereby reducing the light "leaking" through the optical path of the projector. As will be described below, the use of one, or multiple irises, may also be employed to modulate or compensate for lamp brightness, including changes in or decay of the lamp/illumination source.
The addition of an iris does not change the color balance of the illumination (lamp) source or the imager(s); it is spectrally neutral in action. The shape of the iris may also be changed to assist in contrast ratio yields. For example, an oval or "cats eye" shaped iris may lend itself to a better contrast ratio yield than round or multi-sided (polygon) versions. Moreover, the present application contemplates that future implementations could also use extremely fast reacting photosensitive optics that would variably turn darker or lighter to either enhance or replace the mechanical iris method.
A second component employed in the present invention is an Adaptive Luminance Control Module (ALCM), which is coupled to the VLCM. The ALCM is a video signal processing system including circuitry and components that will operate and set the variable aperture opening or opacity of the VLCM and provide a corrected video signal to the input of the projector. This electronic luminance processing will follow the video input signal, tracking either the general (average) illumination level or the brightest point(s) in the signal (i.e., peak level detection) or any combination, and will output two different types of signals:                1) The VLCM drive signal. When fed a resultant, processed (analog or digital) signal, the VLCM will set the general scene illumination level. This optimizes both the engine's contrast (both absolute ON/OFF and ANSI CR) and the lumen output for the particular level of illumination that is needed to accurately reproduce the image. The VLCM drive signal is, effectively proportional to the input intensity of the video image (average or peak). The present invention contemplates the possibility that VLCM feedback may be required, and may employ one or more sensing mechanisms or circuits to indicate VLCM position or condition.        2) The image signal. The video output signal, post processing, is passed on to the projector's imager stage input. This image signal is processed and manipulated to take full advantage of the VLCM optical restriction capability.
This unique relationship is described below. The processing for the image signal is primarily look-up (gamma) and gain based, along with a "black level clamp". Output gamma will not track identically to the input signal's gamma; in other words, it will "adapt" to the input signal's illumination dynamics for optimization with the iris. There are various algorithms that will enable the desired functionality and will improve the technology. As used herein, "black level clamp" is a term describing the input to output signal proportion at 0 IRE. In other words, no matter what function the gamma tables and algorithms perform on the video signal; "0" input always equals "0" output.
In accordance with the present invention, there is provided an apparatus for improving the operation of a digital image projector, comprising: a video input board of the projector; a optical engine of the projector, said optical engine receiving video signals and generating a light output for at least one primary color from; optics for transforming the light output from said light engine to a focused image for projection to a display screen; a variable luminance control mechanism (VLCM), associated with the optics, for receiving the light output and provide a correction thereto; and an adaptive luminance control module (ALCM) or processor, for receiving signals from said video input board, said adaptive luminance control module producing a signal on a VLCM bus connecting the variable luminance control mechanism and the adaptive luminance control module, said signal causing the variable luminance control mechanism to change the luminance of the light output and provide a corrected video signal from the projector.
In accordance with another aspect of the present invention, there is provided a method for improving the operation of a digital image projector, comprising the steps of: receiving image signals from a video input board in the projector; using an adaptive luminance control module, producing an output signal on a VLCM bus connected to the adaptive luminance control module, said signal providing control information for a variable luminance control mechanism, located within the optical path of the projector; and adjusting the variable luminance control mechanism to produce a corrected light output from the projector.
In accordance with yet another aspect of the present invention, there is provided an apparatus for improving the operation of a digital image projector, comprising: a video input board of the projector; a light engine of the projector, said light engine receiving video signals and generating a light output for at least one primary color there from; optics for transforming the light output from said light engine to a focused image for projection to a display screen; a variable luminance control mechanism, associated with the optics, for receiving the light output and provide a correction thereto; and an adaptive luminance control module, for receiving signals from said video input board, said adaptive luminance control module producing a control signal, wherein said variable luminance control mechanism operates in response to the control signal to change the luminance of the light output and provide a corrected video signal for the projector
In accordance with another aspect of the present invention, there is provided a method for improving the operation of a digital image projector, comprising the steps of: receiving video signals from a video input board in the projector; and producing a first signal, using an adaptive luminance control module, to provide control information for a variable luminance control mechanism located within the optical path of the projector and a second signal which is a modified video signal, whereby the variable luminance control mechanism operates to produce a modified light output from said digital image projector.
One aspect of the invention is based on the discovery that the general level of scene illumination may be adjusted in a video projector to improve the effective contrast ratio. This discovery avoids problems that arise in conventional light projectors due to light leakage, etc. Using aspects of the present invention, overall contrast ratio and the available ANSI dynamic for low-brightness images/scenes may be significantly increased. In order to accomplish this function outside of the typical projection-imaging engine, this aspect is implemented using the ALCP and VLCM described herein.
The techniques described herein are advantageous because they can be adapted to any of a number of light projectors. As a result of the invention, it is possible to produce digital light projection systems with improved overall contrast ratios and available ANSI dynamics for low brightness images/scenes.
The present invention will be described in connection with a preferred embodiment, however, it will be understood that there is no intent to limit the invention to the embodiment described. On the contrary, the intent is to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

Method and apparatus for increasing effective contrast ratio and brightness yields for digital light valve image projectors


In a mobile communication system including a transmitter and a receiver, an LDPC code is generated by encoding received information data such that a fifth partial matrix obtained by combining a second partial matrix having even-numbered columns of a first partial matrix corresponding to the information data with a fourth partial matrix having odd-numbered columns of a third partial matrix corresponding to a parity, and an eighth partial matrix obtained by combining a sixth partial matrix having odd-numbered columns of the first partial matrix with a seventh partial matrix having even-numbered columns of the third partial matrix correspond to a ninth partial matrix obtained by exclusive-ORing the first partial matrix and the third partial matrix and a parity check matrix having a predetermined rank in a binary field. A space-time LDPC code is generated by spatial-mapping the LDPC code according to a predetermined spatial mapping scheme.

1. Field of the Invention
The present invention relates generally to a mobile communication system, and in particular, to an apparatus and method for encoding and decoding a space-time Low Density Parity Check (LDPC) code having a full diversity gain.
2. Description of the Related Art
In communications, it is most important to efficiently and reliably transmit data over a channel. In the next generation multimedia mobile communication into which active research is currently being made, it is necessary to increase system efficiency using a channel coding technique appropriate for the system, as there is an increased demand for a high-speed communication system capable of processing and transmitting a variety of information such as image and radio data beyond that of the early voice-oriented service.
Unlike a wired channel environment, a wireless channel environment existing in a wireless communication system inevitably from suffers errors caused by various conditions such as multipath interference, shadowing, propagation attenuation, interference, and fading. These errors commonly cause an information loss in the transmitted data. The information loss seriously distorts actual transmission signals, causing a reduction in entire performance of the mobile communication system.
Generally, in order to reduce the information loss, various error-control techniques are used according to characteristics of channels to increase reliability of the mobile communication system. The most typical error-control technique uses an error correction code.
Mobile communication systems use diversity schemes in order to remove communication instability caused by fading, and a space diversity scheme, one of the diversity schemes, uses multiple antennas.
Generally, the space diversity schemes are classified into a reception diversity scheme using multiple reception antennas, a transmission diversity scheme using multiple transmission antennas, and a Multiple-Input Multiple-Output (MIMO) scheme using multiple reception antennas and multiple transmission antennas. The MIMO scheme is a kind of Space-Time Coding (STC) scheme, and the STC scheme extends a time-domain coding scheme to a space-domain coding scheme by transmitting signals encoded with a predetermined coding scheme using multiple transmission antennas, thereby achieving a low error rate.
FIG. 1 is a block diagram schematically illustrating a transmitter in a conventional mobile communication system using an STC scheme. Referring to FIG. 1, the transmitter includes an encoder 110, a spatial mapper 120, a plurality of signal mappers of first to Mth signal mappers 130-1-to 130-M, and a plurality of transmission antennas (Tx.ANT) of first to Mth transmission antennas Tx.ANT#1 to Tx.ANT#M.
Upon receiving information data, the encoder 110 encodes the received information data into coded symbols at a predetermined coding rate with a predetermined coding scheme, and outputs the coded symbols to the spatial mapper 120. For example, if the information data is comprised of k bits and the coding rate is k/N, the encoder 110 encodes the k-bit information data into N coded symbols.
The spatial mapper 120 spatial-maps the coded symbols output from the encoder 110 with a predetermined spatial mapping scheme such that the coded symbols can be transmitted via the M transmission antennas, and outputs the spatial-mapped signals to their associated signal mappers. There are various possible spatial mapping schemes used by the spatial mapper 120, and it will be assumed in FIG. 1 that the spatial mapper 120 spatial-maps the coded symbols output from the encoder 110 in their output order. For example, if it is assumed that a coded symbol stream output from the encoder 110 is C=[c1,c2, . . . ,cN], an output of the spatial mapper 120 becomes an
  M  ×      N    M  space-time codeword matrix defined as Equation (1).
                    C        =                  [                                                                      c                  1                                                                              c                                      M                    +                    1                                                                              …                                                              c                                      N                    -                    M                    +                    1                                                                                c                  2                                                                              c                                      M                    +                    2                                                                              …                                                              c                                      N                    -                    M                    +                    2                                                                                …                                                                                c                  M                                                                              c                                      M                    +                    M                                                                              …                                                              c                  N                                                              ]                                    (        1        )
Because the number of the transmission antennas is M, the spatial mapper 120 sequentially spatial-maps the coded symbols output from the encoder 110 in their output order, divides the spatial-mapped symbols into M signals, and outputs the M signals to the first to Mth signal mappers 130-1 to 130-M associated thereto. The first to Mth signal mappers 130-1 to 130-M each signal-map the signals output from the spatial mapper 120 with a predetermined signal mapping scheme, and transmit the signal-mapped signals over the air via their associated transmission antennas Tx.ANT#1 to Tx.ANT#M. Here, the first to Mth signal mappers 130-1 to 130-M each signal-map input signals according to a constellation for the predetermined signal mapping scheme, and output the signal-mapped signals to the first to Mth transmission antennas Tx.ANT#1 to Tx.ANT#M, respectively. Each of the first to Mth signal mappers 130-1 to 130-M signal-maps an input signal with a Binary Phase Shift Keying (BPSK) scheme, which shifts a phase in association with a transmission sign using a carrier having constant amplitude and phase, if the number of bits constituting the input signal is n=1; signal-maps the input signal with a Quadrature Phase Shift Keying (QPSK) scheme, if the number of bits constituting the input signal is n=2; and signal-maps the input signal with an 8-ary Quadrature Amplitude Modulation (8QAM) scheme if the number of bits constituting the input signal is n=3.
In FIG. 1, because k-bit information data is transmitted via M transmission antennas, its coding rate is
  M  ×            k      M        .
FIG. 2 is a block diagram schematically illustrating a receiver in a conventional mobile communication system using an STC scheme. Referring to FIG. 2, the receiver includes a plurality of reception antennas Rx.ANT of first to Pth reception antennas Rx.ANT#1 to Rx.ANT#P, a detector 210, a spatial demapper 220, a space-time decoder 230, and a spatial mapper 240. Although it is assumed in FIG. 2 that the number P of reception antennas in the receiver is different from the number M of transmission antennas in the transmitter, the number of reception antennas in the receiver may be equal to the number of transmission antennas in the transmitter.
The signals transmitted by the transmitter via a plurality of transmission antennas (the first to Mth transmission antennas Tx.ANT#1 to Tx.ANT#M) are received at the receiver through the first to Pth reception antennas. The first to Pth reception antennas output their received signals to the detector 210. The detector 210 detects transmission signals transmitted by the first to Mth transmission antennas from the received signals output from the first to Pth reception antennas, and outputs the detected transmission signals to the spatial demapper 220.
The spatial demapper 220 spatial-demaps the signals output from the detector 210 with a spatial demapping scheme corresponding to the spatial mapping scheme used in the transmitter, and outputs the spatial-demapped signal to the space-time decoder 230. The space-time decoder 230 decodes the signal output from the spatial-demapper 220 with a decoding scheme corresponding to the coding scheme used in the transmitter. When there is no error caused by the wireless channel environment, the signal output from the space-time decoder 230 is equal to the information data in the transmitter. Actually, however, because errors occur in the wireless channel environment, the space-time decoder 230 can perform iterative decoding for reliable decoding.
For the iterative decoding, the space-time decoder 230 outputs the signal decoded with a decoding scheme corresponding to the coding scheme used in the transmitter, to the spatial mapper 240. The spatial mapper 240 spatial-maps the signal output from the space-time decoder 230 with a spatial mapping scheme corresponding to the spatial mapping scheme used in the transmitter, and outputs the spatial-mapped signal to the detector 210 in order to perform iterative decoding. The application of the iterative decoding increases the decoding reliability of information data. Thereafter, the signal decoded in the space-time decoder 230 through the iterative decoding is output as the information data.
The term "space-time code" refers to a code encoded with the STC scheme, and the STC scheme, as described above, supplementally acquires additional information by extending a time-domain coding scheme to a space-domain coding scheme. That is, the STC scheme not only reduces an error rate by providing additional information in the time domain, but also increases a diversity gain in the space domain, thereby enabling correct signal decoding. Because the diversity gain corresponds to a slope of a signal-to-noise ratio (SNR) and an error rate of a space-time code, expressed with a log scale, when the space-time code is designed, maximization of the diversity gain (hereinafter, referred to as "full diversity gain") is the most important factor for determining performance of the space-time code.
In order to acquire the full diversity gain, the following Space-Time Code Design Conditions 1-3 should be satisfied in a process of designing the space-time code.
Space-Time Code Design Condition 1
In order to obtain the full diversity gain, a matrix B(c,e) should have a full rank for particular space-time codeword 'c' and space-time codeword 'e'. Here, the matrix B(c,e) is a matrix representing a difference between the space-time codeword 'c' and the space-time codeword 'e'.
Space-Time Code Design Condition 2 should be satisfied, especially when signals are mapped using the BPSK scheme.
Space-Time Code Design Condition 2
A space-time codeword has a full diversity gain, when all non-zero space-time codeword matrixes 'c' have a full rank in a binary field.
Space-Time Code Design Condition 3 should be satisfied, especially when signals are mapped using the QPSK scheme.
Space-Time Code Design Condition 3
A space-time codeword has a full diversity gain, when a space-time codeword matrix Φ(c) obtained by mapping all non-zero space-time codeword matrixes 'c' in a binary field has a full rank.
As described above, the space-time code is designed to have a full rank in order to acquire a full diversity gain. That is, the space-time code is designed such that its generation matrix (G) has a full rank.
The next generation communication system is developing into an advanced communication system providing high-speed, high-capacity data services having various qualities-of-service (QoS). In the high-speed, high-capacity data services, an information loss during transmission is fatal to the services. Therefore, error correction capability of the error correction code functions as an important factor of determining the entire QoS. Typically, the error correction code includes a turbo code and a low density parity check (LDPC) code.
It is well known that the LDPC code is superior in performance gain to a convolutional code that is conventionally used for error correction, during high-speed data transmission. More specifically, the LDPC code is advantageous in that it can efficiently correct an error caused by noises occurring in a wireless channel, thereby increasing the reliability of data transmission. In addition, the LDPC code can be decoded using an iterative decoding algorithm based on a sum-product algorithm on a factor graph. Because a decoder for the LDPC code uses the sum-product algorithm-based iterative decoding algorithm, it is lower in complexity to a decoder for the turbo code. In addition, the decoder for the LDPC code is easy to implement a parallel processing decoder, as compared with the decoder for the turbo code.
The turbo code has excellent performance approximating a channel capacity limit of Shannon's channel coding theorem, and the LDPC code known to have the highest performance shows performance having a difference of only about 0.04 [dB] at a channel capacity limit of Shannon's channel coding theorem at a bit error rate (BER) 10−5, using a block size 107. Shannon's channel coding theorem shows that reliable communication is possible only at a data rate not exceeding a channel capacity.
Generally, although a random code having a very large block size shows performance approximating a channel capacity limit of Shannon's channel coding theorem, when a MAP (Maximum A Posteriori) or ML (Maximum Likelihood) decoding method is used, it is actually impossible to implement the decoding method because of its heavy calculation load.
The LDPC code is defined by a parity check matrix in which the majority of elements have a zero value and a minority of elements except the elements having the zero value has a non-zero value, for example, a value of 1. In the following description, it will be assumed that a non-zero value is a value of 1. Because the parity check matrix of the LDPC code has a small weight, it is possible to perform decoding through iterative decoding even in a block code having a relatively long length. If a block length of the block code is continuously increased, the block code exhibits performance approximating a capacity limit of a Shannon channel, like the turbo code. Herein, the term "weight" refers to the number of elements having a non-zero value among the elements constituting the parity check matrix. Therefore, the next generation communication system tends to actively use the LDPC code as the error correction code.
However, when the LDPC code performs encoding using the generation matrix like the space-time code, performance of the LDPC code cannot be guaranteed. That is, the LDPC code, as described above, is advantageous in that it has low decoding complexity because of the small weight of the parity check matrix, but when the parity check matrix is converted to a generation matrix, a weight of the generation matrix increases, causing an increase in decoding complexity.
As a result, when the space-time code is designed using the LDPC code, it is difficult to apply the foregoing design conditions proposed for the generation matrix of a general space-time code. Therefore, there is a demand for a scheme in which a space-time code using the LDPC code can acquire the full diversity gain, i.e., for a parity check matrix capable of acquiring the full diversity gain.

Apparatus and method for encoding and decoding a space-time low density parity check code with full diversity gain