Abstract: A method of preparing a surface on a die coater to improve the uniformity of the coating layer on the substrate. A surface of the die block is machined. The die block is then positioned on a measuring surface in a free state so that the machined surface being measured is substantially vertical. The vertical orientation of the die block substantially removes the effect of gravity on any residual stress during measuring. The steps of machining, positioning, and measuring the die block are repeated until the desired total indicated run-out is achieved. The positioning step may also include interposing at least two point supports between the die block and the measuring surface. In another embodiment, the die blocks are positioned in a reference state or a production state for measuring.

Abstract: The invention includes a method of generating a position error signal in a holographically imaged data recording system. This method comprises using an optical imaging system to image a plurality of holographically recorded pixels onto a plurality of camera pixels forming a data page. Each holographically recorded pixel is imaged onto an array of at least two adjacent camera pixels in any direction. The output signals from the arrays of camera pixels are used to calculate a position error signal. In a preferred embodiment, the holographically recorded pixel is imaged onto an array of four adjacent camera pixels that form a square having two pixels in each direction.

Abstract: Improved color image display accuracy can be achieved across a computer network by obtaining information characterizing the color response of display devices associated with a client residing on the computer network, and using the information to modify color images delivered to the client. To determine gamma and gray balance, a set of gray elements is displayed against a dithered gray background representing a gray level of approximately 25 to 40% and, more preferably, approximately 33%. In some embodiments, the gray elements and the dithered gray background may be limited to the green color channel of the display device. Dithered backgrounds in the range approaching approximately 33% more closely match the actual midpoint of black to gray transition for most display devices. The gamma and gray balance information can be obtained, for example, by guiding the client through a color profiling process that profiles the color response of the display device.

Abstract: Data recording tape is passed along guides and past a read/write head. Sensors detect the position of the tape and adjust the guides and the head as a function of the position. If the tape deviates from the target tape path, a controller moves a guide to steer the tape back to the target tape path, using the sensor signals. In cases of tape disturbance such as those involving rapid tape motion, an adaptive estimator uses the sensor signals to position the head to anticipate the expected position of the tape when the disturbance arrives at the head.

Abstract: The position of one or both edges of tape, such as magnetic tape, can be determined using a light source, such as a solid-state laser with a collimated beam, and a detector, such as a photodiode. The tape, by blocking a portion of the light, affects the amount of light reaching the detector. The detector generates signals as a function of the position of the tape. In the case of two detectors cooperating to measure the positions of opposing edges of the tape, the signals from the detectors may be processed to produce at least four useful signals, including a signal that is a function of the tape width and a signal that is a function of the position of the tape centroid.

Abstract: A data storage tape cartridge including a housing, first and second tape reels, a storage tape, first and second corner guides and an idler wrap guide. The housing defines a head access window. The tape reels are rotatably disposed within the housing, with the storage tape extending between the tape reels. The first and second comer guides are disposed within the housing at opposite sides of the head access window. Finally, the idler wrap guide is disposed within the housing and defines a tape path extending from the first tape reel to the idler wrap guide, and from the idler wrap guide to the first corner guide. The idler wrap guide is configured to frictionally dampen lateral movement of the storage tape upon rotation of the tape reels to greatly reduce servo off track events.

Abstract: Playback transducers for patterned media systems comprise temperature sensitive resistors, including thermistors and resistance temperature detectors. The transducers are typically thin film depositions mounted on a slider for flying head application. Possible configurations are generally V-shaped, may involve parallel or perpendicular recording geometry, and are conceptually similar to (but simpler in construction than) magnetoresistive or giantmagnetoresistive thin film transducers. The transducers may incorporate supplementary heating elements and/or coatings to optimize performance.

Abstract: A data storage tape cartridge (10) includes two tape guides (23, 24). The tapes guides (23, 24) have a foil (43, 143, 243) which is constructed from material which causes a wear pattern (200) to be formed in the foil (43), thereby removing localized forces and spreading out the forces and thereby decreasing the tape pressure.

Abstract: Magnetic patterned media comprise topographical features readable with a slider-mounted non-magnetic transducer sensitive primarily to a local aerodynamic boundary condition, in addition to a magnetic recording layer substantially conforming to the topographical features. Passage of a transducer over the features generates effects that can be detected in, and separated from, the magnetic recording signal.

Abstract: System for releasably retaining portions of a data cartridge shell in an assembled configuration including at least one first boss tower on a first portion of the data cartridge shell having a receiving hole with an inner surface. At least one second boss tower on a second portion of the data cartridge shell including an outer surface is adapted to releasably engage with the receiving hole at a boss tower interface in the assembled configuration. A plurality of retention ribs and a plurality of guide ribs are located at the boss tower interface to releasably retain the first portion of the cartridge shell to the second portion.

Abstract: A disc molding apparatus for forming an optical disc. The apparatus has a disc substrate cavity and a sprue mechanism in fluid communication with the cavity. A removable stamper located on one side of the disc substrate cavity forms data onto the disc substrate and the stamper is relasibly locked within the apparatus by an inner holder, which includes a locking mechanism. The apparatus also has a mechanism that forms a disc alignment mechanism in the disc substrate wherein the disc alignment mechanism is between the formatted data and a center of the disc substrate and the concentricity of the formatted data is specified relative to the disc alignment mechanism.

Abstract: Methods and systems for laser etching of optical servo patterns on magnetic data storage media using two or more beams of laser energy produced from a single source of laser energy to produce a servo pattern on the magnetic data storage media. By using two or more etching beams, the time required to produce a servo pattern on the magnetic data storage media can be significantly reduced. Alternatively, each servo track in the servo pattern can be written more than once. The servo patterns thus formed can be read optically or they may be read magnetically using magnetic overwriting (if the servo pattern is formed in a magnetic coating on the media). In either case, the servo patterns are either permanently formed in the media when read optically, or they can be recreated after bulk erasing if they are provided using magnetic overwriting. In yet another alternative, the servo patterns may be read both magnetically and optically, with the magnetic and optical reading occurring simultaneously or sequentially.

Abstract: A method of making a stamper for use in a data storage disk molding process. The method includes making a first stamper including the steps of providing a stamper body having an information layer thereon. The information layer is covered with a first metal layer. A second stamper is made from the first stamper, which includes the steps of covering the first metal layer with a second metal layer to form a stamper assembly, wherein the first metal layer and the second metal layer are bonded together. The first metal layer and the second metal layer are removed from the stamper assembly to form the second stamper, wherein removal of the first metal layer and the second metal layer is nondestructive to the information layer. In one application, the first metal layer and the second metal layer are made of nickel.

Abstract: Disclosed is a stamper assembly for forming an optical data storage disk in a disk molding process. The stamper assembly includes a block element having a first major surface, and a stamper member having a first major surface and an opposite, second major surface. The first major surface of the stamper member is adapted to contact a disk molding material for forming an optical data storage disk in a disk molding process. The stamper assembly further includes a medium for securing the stamper member to the block element, such that substantially the entire second major surface of the stamper member is affixed to the first major surface of the block element. This arrangement prevents relative movement between the stamper member and the block element. This substantially reduces stamper member wear and increases the useful production lifetime of the stamper assembly.

Abstract: A data storage cartridge includes a length of magnetic tape wound on a pair of tape reels within a housing to define a tape path. A tape guide disposed along a portion of the tape path includes a top and bottom flange. Each flange is resilient so that it acts to resiliently guide an edge of the tape. This minimizes violent crashes of a tape edge against the tape guide. Each flange may have a plurality of spaced resilient finger guides for directly contacting the edges of the tape. The finger guides serve to independently exert a force on the edges of the tape, thereby guiding the tape.

Abstract: The present invention provides methods and apparatus for stabilizing data storage media during laser servowriting of optical servo tracks on the media. The apparatus includes a spindle for rotating the media during servowriting, a fixed media platform, and a media support for stabilizing the vertical position of the media during servowriting. The media support may include channels to reduce or control the formation of an air bearing in the area of servowriting to stabilize the vertical positioning of the media. The media support may also include a vacuum slot for drawing a vacuum through the channels.

Abstract: A data storage cartridge (10) includes a housing (12) having a first section (13) and a second section (14) operatively connected to each other. A first positioning member (40) and second positioning member (50) are operatively connected to the housing and are in axial alignment with each other. A leader pin (30) is positioned in the positioning members (40 and 50). Springs (60 and 70) secure the leader pin (30) in position. A flexible locking post (82) provides a snap fit in an opening (92) and provides for two perpendicular pairs of locking surfaces to form a snap fit between the sections (13 and 14).

Abstract: Improved color image display accuracy can be achieved across a computer network by obtaining information characterizing the color response of display devices associated with a client residing on the computer network, and using the information to modify color images delivered to the client. The information may include a gamma estimate and a gray balance estimate. In one embodiment, the gamma estimate is limited to only the green color channel, without reference to the gammas for the red and blue channels. Then, the gray balance of the display device is estimated using the green-limited gamma estimate as a starting point, in combination with a number of red-blue shifts away from the gamma estimate. In particular, in the gray balance process, the green intensity value indicative of the gamma estimate is used to generate a set of gray patches that exhibit +/− (plus/minus) differences or “shifts” in red and blue away from the green value.

Abstract: A clearance-type tape guide for guiding a recording tape along a tape path having two tape reels. The tape slidably engages the tape guide along a surface having a length L1. The tape travels along the tape path for a distance L2 between the tape guide surface and the closer of the tape reels. According to the invention, L1≧0.3 L2.

Abstract: Release compositions include (a) from zero to about 30 parts by weight of a polymer selected from the group consisting of wherein R1, R2, R3, R6, R7, R10, R11, and R12 are each independently selected from an alkyl group, an alkenyl group, an aryl group, and an aralkyl group, such that at least one of R6 and R7 is an alkenyl group, l, m, and n are each independently an integer so long as the polymer contains greater than 3 mol % vinyl-containing siloxane groups; a (vinyl siloxy)(siloxy)-modified silica having a vinyl content of at least about 0.