Abstract: An automatic level-sensitive Laplacian filter for image processing. Laplacian filter coefficients and normalization divisors are made a function of intensity on a pixel by pixel basis. Pixels indicating a high intensity may be greatly changed by neighboring pixels. Pixels indicating a low intensity receive relatively little or no filtering. In a specific example embodiment, the intensity range is divided into bands, with a different filter for each band. The resulting images are visually sharpened (edge enhanced) with very little impact in darker areas of the image.

Abstract: A method for reliably measuring preformatted servo patterns, on a magnetic tape, for positioning a magnetic head. The tape has constant frequency stripes marking servo pattern areas. The drive reading the preformatted tape has a read channel amplifier with automatic gain control (AGC). When a stripe is detected, AGC is enabled. Before leaving a stripe, AGC is placed on hold. The amplitudes of two servo bursts are then measured with a gain that has been calibrated by a signal from a stripe. During the time AGC is enabled, the amplifier peak output is limited to less than half the maximum amplifier peak output. The servo pattern signal amplitude is about twice the signal amplitude of a stripe, so that servo patterns are measured with almost the maximum signal-to-noise ratio. When a stripe is detected, a counter counts pulses resulting from the stripe signal, for a fixed time, to ensure that the stripe detection is valid.

Abstract: A dynamic logic circuit having additional test circuitry and control, enabling the dynamic logic gate to operate normally during testing or alternatively to force the dynamic logic gate output to a known state during testing to provide a known input for downstream logic. With the additional test circuitry, there is no need for input test signal sequences to propagate logical test vectors to tested nodes. The dynamic logic circuit includes a storage node that is precharged during a precharge cycle and logic circuitry that may discharge the storage node during an evaluation cycle, depending on logic inputs. The logic circuitry discharges through a clock transistor. Additional test circuitry is added to discharge the storage node during the evaluation cycle, in response to a test control signal and a test state signal. When the dynamic logic gate is operating normally during testing, the test circuitry is disabled.

Abstract: A method of inhibiting copying of digital data. In a first embodiment, a sequence of symbols is added to original data, the sequence of symbols selected to encode into channel bits having a large accumulated digital sum variance. The sequence of symbols is then encoded by a special encoder that generates special channel bits that don't have a large accumulated digital sum variance. The special channel bits may be unambiguously decoded, but the resulting decoded symbol sequence will likely be reencoded into channel bits having a large accumulated digital sum variance. In a second embodiment, a single symbol in the sequence of symbols is replaced after error correction symbols have been added. The sequence of symbols with one substituted symbol is encoded into channel bits that don't have a large accumulated digital sum variance.

Abstract: A method of improving the performance of a computer processor by recognizing that two consecutive register instructions can be executed simultaneously and executing the two instructions simultaneously while generating a single data address and while performing exception checking on a single data address. During an instruction fetch process, two consecutive instructions are tested to determine if both are either register load instructions or register save instructions. If both instructions are load or save register instructions, the corresponding data addresses are tested to see if both data addresses are in the same double word. If both data addresses are in the same double word, then the instructions are executed simultaneously. Only one data address generation is required and exception processing is performed on only one data address.

Abstract: A process for creating new software procedures during run time. An applications program calls a procedure that indirectly corresponds to a set of variables. A library determines that the procedure is not already defined in the library. In a first embodiment, the library builds a source code file to be compiled. In a second embodiment, the library object code creates a string of directives that form part of a command line calling a compiler. The compiler compiles a source code file, selectively compiling only portions of the source code file designated by the command line directives that were created by the library code. For either embodiment, the resulting newly compiled procedure is provided to the applications program by the library in a manner that is transparent to the applications program. No changes are required to the applications program or to the compiler.

Abstract: A method of filtering images with a filter that is dependent on image type. For binary images, a fixed Laplacian filter is used for all pixels. For non-binary images, an automatic level-sensitive Laplacian filter is used. For non-binary images, Laplacian filter coefficients and normalization divisors are made a function of intensity on a pixel by pixel basis. Pixels indicating a high intensity may be greatly changed by neighboring pixels. Pixels indicating a low intensity receive relatively little or no filtering. In a specific example embodiment, the intensity range is divided to bands, with a different filter for each band. The resulting images are visually sharpened (edge enhanced) with very little impact in darker areas of the image.

Abstract: A method of measuring and compensating the effects of stray light in a spectrometer and use of the method to improve linearity and accuracy in the spectrometer. Light from a broadband light source (100) is blocked in a particular band of wavelengths by an optical filter (104) and light outside the particular band of wavelengths is transmitted by the filter. A spectral measurement within the particular band measures aggregate offset, including the effects of stray light, dark current and electronic offset. In absorption spectrometry, a first spectral measurement within the particular band is measured with a chemical sample not present and a second measurement is made with a chemical sample present. The first spectral measurement is used for compensation of a reference spectrum and the second spectral measurement is used for compensation of a sample spectrum, each within the particular band.

Abstract: A container for a recordable compact disc. The container includes a window area with adjacent scales. A boundary between a recorded area and an unrecorded area on the compact disc is visible through the window area. The adjacent scales indicate recorded time, remaining time, recorded data in megabytes or remaining capacity in megabytes.

Abstract: A method and apparatus for mixing liquids using electroosmotic flow. Multiple capillaries (100, 104, 106) or microchip channels meet at a common junction (102). One capillary (100) is used for mixed liquids and each of the remaining capillaries (104, 106) are used for supplying a liquid (112, 114) to be mixed. Each of the supply capillaries (104, 106) has a free end that is immersed into a vial (108, 110) of liquid (112, 114). A first power supply terminal (112) is attached to a free end of the mixed liquid capillary (100). The liquid in each vial has an electrode that is switchably connected to a second power supply terminal. Closing a switch (116, 118) causes liquid to flow from a vial through the common junction and through the mixed liquid capillary. Each switch is independent and each may be closed continuously, switched at a constant duty cycle, or switched at a variable duty cycle. As a result, continuous mixing or variable ratio mixing may be achieved.

Abstract: A sensor assembly and an optical image color scanner using the sensor assembly. The sensor assembly is of the type having three separate rows of optical sensors. Two of the three sensor rows have color filters and one is unfiltered (receptive to white light). For gray scale scanning, only the unfiltered (white) sensor row is used, thereby maximizing the speed of gray scale scanning. For color scanning, three color values are computed as a linear transformation of values from the two filtered and one unfiltered values. The linear transformation may be as simple as subtracting signals from the two filtered sensor rows from the signal from the unfiltered (white) sensor row. For color scanning, memory buffers are required for two of the three sensor output signals. For highest accuracy in color scanning, the exposure time for the white sensor row is reduced relative to the exposure time for the two filtered sensor rows.

Abstract: A computer Input/Output (I/O) subsystem providing communication and control between a computer and external audio and telephone devices. The external signals include stereo audio input signals, stereo audio output signals for headphones, monaural audio microphone input signal, monaural audio output signal for a speaker, analog telephone lines and ISDN. Data to and from the multiple computer I/O ports and data to and from the multiple external devices is all merged for communication over a single time-domain-multiplexed full-duplex serial bus. The telephone circuit is designed as an option and is either analog or ISDN. When the telephone circuit is installed, the serial bus is automatically reconfigured to accommodate the additional data and control information. The telephone circuit transparently merges serial telephone data and serial audio data. For example, MODEM data I/O can occur simultaneously with audio sample data.

Abstract: A method of testing series passive components in electronic assemblies. Only one test pin per passive component is required, thereby reducing the cost and complexity of test fixtures and the electronic assemblies. A passive component is connected between the output of a driving circuit and (optionally) an input of a receiving circuit. The output of the driving circuit is placed in a low impedance state. The receiving end of the passive component is stimulated and the response is measured. For reactive components, the stimulus and response are AC. For resistors, multiple DC measurements may be made. A optional DC bias may be provided to limit DC current and to further reduce the small signal output impedance of the driving circuit.

Abstract: An electrode for an external electrode fluorescent lamp. The lamp has intensity striations. The electrode has a periodic non-uniform area sufficient to cause a periodic non-uniformity in the electric field between two electrodes. The non-uniformity of the electric field is sufficient to prevent wandering of the striations. The striations have a range of pitch. The pitch of the area in the electrode is within the range of pitch of the intensity striations. Examples of non-uniform areas include serrated or sinusoidal edges and circumferential slits.

Abstract: A method and apparatus for mounting an optical sensor in an optical instrument. The optical sensor is attached to a rigid substrate. The substrate has two locator holes, with the sensor mounted between the holes. Rigid locator pins attached to the housing of the instrument protrude into the locator holes. A spring pushing against the substrate forces the locator holes against corresponding locator pins, aligning the substrate within a plane. In a first embodiment, the holes are positioned so that the optical sensor is rigidly held at its midpoint, minimizing dimensional deviations along the length of the sensor with temperature change. The sensor assembly is easily removable and the mounting apparatus does not mechanically stress the substrate or the sensor with temperature changes. The mounting apparatus is easily manufactured, allows precise alignment, and is inexpensive.

Abstract: An intergrated circuit package with plastic or glass reinforcement of leads to increase lead rigidity, to improve lead alignment and positional stability, and to prevent bent leads. The invention is particularly applicable to surface mount packages. For plastic packages, plastic between the leads is formed during molding of the plastic package. For metal packages, the plastic is molded as a separate operation. For ceramic packages with lead frames, glass may be formed as a separate operation or may be formed at the same time as a glass seal for the ceramic package. Reinforcement can optionally be thicker than the leads for increased rigidity. Optional extended lead lengths enable plastic or glass to be formed on either side of the soldered foot area of each lead. No changes to test fixtures or to pick and place equipment are required.

Abstract: A tape drive having a protection barrier to keep improperly inserted tape cartridges from damaging the read/write head. In a first embodiment of the invention, a short protection wall is positioned in front of the read/write head. This protection wall prevents a tape cartridge inserted sideways into the tape drive from contacting the read/write head. The protection wall also prevents a partially opened cartridge door from striking the read/write head. In a second and third embodiment of the invention, one or more protection pins are used to protect the read/write head. These protection pins also keep a cartridge inserted sideways into the tape drive or a cartridge door partially opened from striking the read/write head.

Abstract: A robotic gripper with two fingers for friction gripping. The fingers are self-locking in that an increased resistance to a pulling force results in an increased gripping force. The fingers are mounted onto a thumb that slides in a sleeve. A post extends into slots in the fingers so that movement of the post relative to the thumb causes the fingers to rotate around pivot points on the thumb. The friction force required to move the thumb relative to the sleeve is greater than the friction force required to move the post relative to the thumb. Therefore, movement of the post typically results in rotation of the fingers and a stationary thumb, but there are several ways in which the post can be locked relative to the thumb to provide movement of the thumb relative to the sleeve. The sleeve also includes features so that if an object is being gripped as the post is moving away from the sleeve, the fingers do not grip when the post is retracted.

Abstract: A system and method for automatically enabling and disabling a termination impedance circuit for a computer bus. A peripheral device on the computer bus has two external bus connectors. A connector cover is provided for at least one of the peripheral bus connectors. The connector cover must be removed before a mating bus cable connector can be attached. The presence or absence of the connector cover is detected by sensor within the peripheral device. If a connector cover is detected, one of the peripheral bus connectors must be open (not connected to the bus) and termination is enabled. If a connector cover is not detected, termination is disabled. In one embodiment, the connector cover has a projection that passes into the peripheral device. In an alternative embodiment, a reflective surface is used. The cover may optionally be captured by a hinged edge or attached via a tether.