Abstract: A hand-held bar code reader includes a laser scanning module and a two dimensional image sensor and processing for reading a bar code. The laser scanner assists the 2D image processing by providing information on location, type, range, reflectivity, and presence of bar code for 2D reading. Additionally, the 2D imaging reading operation is improved by using the laser scan as a spotter beam for aiming.

Abstract: An apparatus for viewing a retroreflective object positions a light source proximate a human eye, by affixing it to, for example, a pair of goggles. The light source emits light outward in substantially the direction of view of the human eye. Upon striking a retroreflective object, the light is strongly reflected back to the human eye, producing a unique visual effect. The apparatus may be used in toy form to simulate a night vision scope. Various combinations of colored light sources, optical color filters interposed between the human eye and the retroreflector, and colored retroreflectors may be used to enhance the visual effect and increase the play variations available. The light source may switch on and/or off automatically, or may flash. Electronic light sensing means may provide a visible and/or audible alert when a retroreflective object is in view.

Abstract: A method for determining degrees of freedom of an object, and in particular, to a device for determining up to six degrees of freedom of a head mount display and a handle. A first camera is attached to a head mount display and senses an optically modulated target. The first camera's video output signal is processed with a digital computer to determine the position and orientation of the head mount display. A second camera is attached to a head mount display and senses an optically modulated target attached to a handle. The second camera's video output signal is processed with a digital computer to determine the position and orientation of the handle.

Abstract: A method for determining up to six degrees of freedom of a camera relative to a reference frame comprises sensing an optically modulated target with the camera and processing the camera's video output signal with a digital computer. The target may have a single pattern, multiple patterns, or patterns of varying size. Multiple targets may also be used. A very wide field of view camera may be used in conjunction with a method for removing geometric distortion from the camera's view. Target patterns may be transmissive, reflective, or retroreflective, or may actively emit light. Asymmetric patterns are used to eliminate ambiguity in the recovery of the degrees of freedom.

Abstract: A bar code reader includes a first and second memory arrangement in which a two dimensional image containing the image of a bar code symbol at a random location and orientation is stored in a first memory. Thereafter, the contents of the first memory is processed by a specialized controller to determine whether any portion of the stored image is likely to contain a bar code symbol, and if so, at what location. If a bar code symbol is located, then the portion of the image stored in the first memory which has been identified as likely to contain a bar code symbol is transferred to a second memory. In the second memory, the stored image is processed by a digital signal processor in order to orient, filter and scan the stored bar code image.

Abstract: A hand-held bar code reader with a two dimensional image sensor for omnidirectional bar code reading, includes variable imaging optics, and flash illumination with variable flash illumination optics. A spotter beam is provided for aiming the hand held bar code reader at a bar code symbol. The spotter beam is also used to measure the range to said bar code from said hand held bar code reader and to determine the focal length of said variable imaging optics and variable flash illumination optics. The imaging optics are adjusted automatically to provide the correct magnification and focus of a bar code regardless of range to the label. The variable focal length flash illumination optics are used to concentrate illumination energy only in the field of view of the bar code reader. The flash illumination energy is conserved by measuring the ambient light and setting the level of flash illumination energy in accordance with the measured level of ambient light.

Abstract: A bar code reader includes an image capture means for storing a two dimensional image in memory, which stored image may include a bar code symbol within the field of view of said image. The present bar code reader further includes method and apparatus for determining the location and orientation of said bar code symbol within the field of view of said image, and then filtering said located and oriented bar code symbol along an axis perpendicular to said detected orientation. Thereafter, the filtered bar code symbol is scanned and applied to a decoder to produce a decoded bar code output.

Abstract: A bar code reader utilizing a two dimensional image capture optical system, includes a method and apparatus for distinguishing a preferred bar code out a plurality of bar codes within the field of view of the bar code reader. The method and apparatus for distinguishing a preferred bar code includes placing a special pattern proximate to the bar code to be distinguished. In one embodiment, a predetermined pattern at a predetermined location and orientation relative to the bar code is placed on a label. The reader includes means for detecting the presence of the predetermined pattern after the bar code has been located. The bar code reader first locates each of the plurality of bar codes, and then checks each located bar code to determine whether the predetermined pattern is present. If the predetermined pattern is detected, then the corresponding located bar code is scanned and decoded as the preferred bar code.

Abstract: A multiple resolution optically encoded label is readable at two or more optical resolutions, and is able to store two or more respective channels of optically encode information. Low resolution information is encoded in a plurality of large cells arranged in a predetermined geometric pattern. Each of the large cells includes a plurality of smaller cells for storing high resolution information. Method and apparatus are disclosed for encoding both high resolution data, and low resolution data, as well as for finding and reading both high resolution and low resolution data.

Abstract: An optically encoded information bearing label containing a two dimensional array of data cells includes a finder pattern comprising a plurality of spots arranged in a predetermined geometric pattern substantially analogous to the predetermined geometric pattern of said two dimensional array of data cells. The finder pattern is detected by first scanning the image area to detect spots. The locations of detected spots are compared to the known geometry of the finder pattern in order to provide for rapid and reliable finding of the finder pattern and the information bearing label. Additionally, the detected finder pattern spots provide information for decoding the two dimensional data array in order to compensate for label magnification, tilt and other distortions.

Abstract: A bar code reader includes an optical system for storing a two dimensional image in memory, which stored two dimensional image contains a bar code symbol. A method and apparatus is disclosed for detecting the location of said bar code image by computing the accumulated sum of the products of the derivatives of respective first and second scan lines as a location score for the image under consideration. The higher the location score, the higher the probability that the area under consideration contains a bar code image. Also, a method and apparatus is disclosed for determining the fine orientation of a located bar code image by the cross-correlation of interpolated scan line data. The bar code image is filtered by shifting interpolated scan line data in accordance with the detected peak of the cross-correlation and combining the shifted scan line data.

Abstract: A multiple resolution optically encoded label is readable at two more optical resolutions, and is able to store two or more respective channels of optically encoded information. Low resolution information is encoded in a plurality of large cells arranged in a predetermined geometric pattern. Each of the large cells includes a plurality of smaller cells for storing high resolution information. Method and apparatus are disclosed for encoding both high resolution data, and low resolution data, as well as for finding and reading both high resolution and low resolution data.

Abstract: An omnidirectional bar code reader uses a virtual scan of raster scan digital image memory to create the equivalent scanning pattern of a mechanical laser scanner. A two dimensional image of bar code symbol at any random orientation is captured in a memory. In one embodiment, the image memory is scanned to create a virtual scan equivalent to the scan pattern of a laser scanner. In another embodiment, the image memory is divided into plurality of memory segments, and simultaneous virtual scan is provided in each of the respective memory segments. In yet another embodiment, the memory is divided into a plurality of overlapping memory segments and simultaneous virtual scan is provided in each of the respective overlapping memory segments. The overlap between the memory segments is made large enough so that a bar code symbol of the expected size will be entirely included in one or the other of the overlapping memory segments.

Abstract: The article of the invention is an optically readable label for storing encoded information, said label comprising a data array of a multiplicity of information-encoded polygons arranged in a predetermined geometric pattern, and said polygons having at least two different optical properties.a process for encoding information in an optically-readable data array comprised of information-encoded polygons by assigning optical properties to individual polygons in a predetermined pattern, ordering the polygons in a predetermined sequence, and printing the polygons with at least two optical properties.A process for retrieving information by optically scanning a data array of information-encoded polygons, preferably hexagons, creating an optical replica of the digital bit stream representative of the optical properties of the information-encoded polygons, decoding that optical replica and retrieving the decoded bit stream.A system for performing the foregoing encoding and decoding processes.

Abstract: The article of the invention is an optically readable label for storing encoded information, said label comprising a data array of a multiplicity of information-encoded polygons arranged in a predetermined geometric pattern, and said polygons having at least two different optical properties. A process for encoding information in an optically-readable data array comprised of information-encoded polygons by assigning optical properties to individual polygons in a predetermined pattern, ordering the polygons in a predetermined sequence, and printing the polygons with at least two optical properties. A process for retrieving information by optically scanning a data array of information-encoded polygons, preferably hexagons, creating an optical replica of the digital bit stream representative of the optical properties of the information-encoded polygons, decoding that optical replica and retrieving the decoded bit stream. A system for performing the foregoing encoding and decoding processes.

Abstract: The article of the invention is an optically readable label for storing encoded information, said label comprising a data energy of a multiplicity of information-encoded hexagons contiguously arranged in a honeycomb pattern, and having at least two different optical properties.A process for encoding information in an optically-readable data array comprised of a honeycomb of contiguous hexagons encoded by assigning optical properties to individual hexagons in a predetermined pattern, ordering the hexagons in a predetermined sequence, and printing the hexagons with at least two optical properties.A process for retrieving information by optically scanning an information-encoded data array of contiguous polygons, preferably hexagons, creating an optical replica of the digital bit stream representative of the optical properties of the information encoded polygons, decoding that optical replica and retrieving the decoded bit stream.A stream for performing the foregoing encoding and decoding processes.

Abstract: A signal transition detection circuit detects a transition which satisfies predetermined criteria related to magnitude and time. These criteria include that the magnitude of a group of signal samples preceeding the transition and a group thereof following the transition each be relatively close in magnitude and that the difference between the magnitudes of signal samples preceeding and following the transition be at least a predetermined amount. Further, detection criteria are included to test for smoothness and monotonicity of the transition and to exclude detection of transitions having magnitude changes exceeding a predetermined amount.

Abstract: A signal transition enhancement circuit detects transitions in the magnitudes of successive sampled data signals and substitutes certain data samples preceeding and following the transition for certain other data samples within the transition, thereby to decrease the number of data samples required to complete the transition. As a result, the rise and fall times of signals developed in response to the sampled data signals will be reduced. A transition is detected when respective sampled data signal magnitudes within two groups of successive samples are respectively relatively close in magnitude and the magnitudes of two selected signal samples differ by at least a predetermined amount.

Abstract: A color TV receiver designed to digitally process I and Q color mixture signals incorporates chroma gain control, static tint control and autoflesh in the circuitry for converting the I and Q signals to (R-Y), (B-Y) and (G-Y) for R,G,B matrixing. The magnitude and angle of the vector sum of I and Q are first determined. The angles are then adjusted for static tint control and then applied to a ROM which is programmed to output angles adjusted for fleshtones. Angles from the autoflesh ROM are applied to a summing circuit which algebraically adds to the flesh corrected angle, angle values corresponding to the angular displacement between the I axes and the (R-Y), (B-Y) and (G-Y) axes. The angles produced by the summing circuit are applied to a look-up ROM which produces the cosine values of the applied angles.The magnitude signal is amplified by coefficients which relate the I and Q signals to (R-Y), (B-Y) and (G-Y) components and which coefficients may be amplified by a chroma gain signal.

Abstract: A method is described for generating continuously variable sets of weighting coefficients for application to weighting circuits of a sampled data filter. The generated coefficients are produced by scaling the time axis of the impulse response described by a set of standard or nominal weighting coefficients in an inverse manner to a desired scaling of the filter frequency response. The coefficient values at the scaled time points are calculated by a piecewise linear interpolation process and correspond to the scaled coefficients. By this technique, a large number of sets of weighting coefficients may be generated from a single set of coefficients with relatively few circuit elements.