Abstract: An information code has a positioning layer for coding position information and a data layer for coding arbitrary non-positional data. Both the positioning layer and the data layer may be formed by circularly shifted instances of a window sequence. A product may have information code. Further, the information code may be coded and decoded by using methods for coding and decoding and may be decoded by using an apparatus.

Abstract: A modular unit is designed for an electronic pen. The modular unit comprises a carrier (70) with a receiver for a writing implement, a printed circuit board (72), a two-dimensional radiation sensor (78) mounted on the printed circuit board, and an imaging unit (82) which defines an image plane. The carrier (70), the printed circuit board (72), and the imaging unit (82) are joined together with the imaging unit (82) facing the radiation sensor (78) to locate the image plane at the radiation sensor (78). The modular unit may comprise an analysis system dedicated to a particular optical analysis application, such as position determination based on images of a position-coding pattern. A radiation source, such as an LED or a laser diode, may be arranged on the printed circuit board or mounted in a holder on the imaging unit. The imaging unit (82) may be implemented as a boresight unit for controlling the spatial origin of radiation transmitted towards the radiation sensor (78).

Abstract: A position code is recorded by capturing a sequence of images while writing on the base with a user unit. The position code may be decoded to a sequence of absolute positions reflecting the movement of the user unit over the base. If the position code in any image is not sufficiently recorded, e.g. because it is obscured by other graphics on the base, the spatial relationship of the image to another image in the sequence is determined. If the position code in this other image in the image sequence is decodable to an absolute position, the absolute position of the image in which the position code is not decodable could nevertheless be determined by using the spatial relationship. In this way the movement of the user unit can be recorded even though the position code is obscured, which could be the case when the same printing ink is used for both the position code and other graphics on the base.

Abstract: An information management system comprises a product provided with a position code a digital pen capable of reading the position code, a look-up unit, and a plurality of databases connected to the digital pen via a first communication path. The databases include a pen database, a position database, and an event database. The information management system also includes an interface unit, separate from the look-up unit, and used to provide access to the pen database, the position database, and the event database via a second communication path that is separate from the first communication path.

Abstract: A computer-implemented method is designed for on-demand printing on digital printers of a coding pattern to code data on a surface. The coding pattern comprises a plurality of parallel number sequences which represent different rotations of a cyclic number sequence. The method could involve retrieving a digital representation of the coding pattern, and identifying the rotations therein to derive shift information which designates a phase difference between each rotation and the cyclic number sequence. In the printing operation, all the different rotations may be represented by the cyclic number sequence embodied as at least one code block image. This code block image is repeated in accordance with the shift information to form a printable image in the printer.

Abstract: A computer-implemented method is designed for printing on regular digital printers of a coding pattern consisting of regularly spaced code symbols. In the method, a page-describing code (e.g. in PostScript programming language) is generated for the printer. The generation of the page-describing code is based a character definition set which assigns a set of characters to represent a set of mutually unique groups of the code symbols. By mapping the set of mutually unique groups against the coding pattern, the location of corresponding groups within the coding pattern can be identified. Each of the corresponding groups is then represented by its assigned character in the page-describing code. The resulting page-describing code is small in size and has a reduced set of printer instructions that can be processed efficiently by the receiving printer.

Abstract: A system for information management comprises a central unit and a plurality of user units which are arranged to record information and send the information to the central unit. Particulars are stored in the central unit about a plurality of regions, each of which represents an area on at least one imaginary surface. One of the user units records information which comprises at least two coordinates and sends the information to the central unit. When the central unit receives the information from the user unit, it identifies to which region the coordinates belong and determines how the information is to be managed, based on the region affiliation.

Abstract: A method and a computer program are described for developing a product (110), and services associated with the product, which product has at least one activation area (308) which is provided with a position code (403) that codes at least one position on an imaginary surface (601), which position causes a device (710) that detects the position code (403) to initiate an operation that utilizes information recorded by the device (710). A digital representation of at least part of the product comprising image points is produced, each image point in the digital representation of the activation area (308) corresponding to a position on the imaginary surface (601). A digital template that can be used for making the digital representation of the product is also described.

Abstract: An optical system comprises an imaging arrangement (1?, 1?) that transmits an image to an image plane; a sensor; and one or more locator elements that locate the imaging arrangement (1?, 1?) to provide the image on the sensor. Tolerances of the locator element(s) allow a lateral translation and a rotation of the imaging arrangement (1?; 1?) around a nominal rotation point. A parameter of the optical system is selected such that a movement, resulting from either the lateral translation or the rotation, of an optical axis (OA) on the sensor is at least partly counteracted by a movement, resulting from either the lateral translation or the rotation, of the image on the sensor with respect to the optical axis (OA). Thereby, the optical system is wholly or partly self-compensating with respect to tolerances affecting the angular position or the lateral position of the imaging arrangement.

Abstract: An electronic pen has a body which comprises a casing consisting of at least two casing parts which are joined to be separable, and electronic equipment arranged inside the casing. A girdle is arranged with a close fit round the joined casing parts. The casing and the girdle have coacting locking means which limit the movement of the girdle in the longitudinal direction of the pen in such manner that at least the girdle is destroyed as the locking is broken.

Abstract: A method, in an apparatus for position decoding, operates to extract a sequence of positions from a sequence of images of a position-coding pattern, as recorded by a sensor. The method, which may be embodied as a computer program on a computer-readable storage medium, involves the steps of retrieving at least one reference position (P1, P1?); and extracting the sequence of positions solely by matching information obtained from each of the images with a corresponding pattern reference area (MA), which represents a known subset of the position-coding pattern with a given, direct or indirect, spatial relation to the reference position(s).

Abstract: The invention relates to a method for generating a printout of a section of a global position-coding pattern in a system comprising a computer unit and a printer unit connected to the computer unit. The method is characterized by the steps of generating in the computer unit boundary information that describes the boundaries of the section in the global position-coding pattern; transmitting the boundary information from the computer unit to the printer unit; generating graphical information in the printer unit by means of an algorithm that defines the global position-coding pattern and on the basis of the boundary information, which graphical information describes pattern symbols in the section; and printing out the graphical information on a base by the printer unit.

Abstract: In an information code which is arranged to redundantly code at least one first information element by means of a first information element, one or more of the marks can be omitted for the coding of at least one additional information element. In addition, copy protection can be created for an information code that codes at least one first information element by means of a plurality of marks by the addition of at least one interference mark whose optical characteristics differ from those of the marks in the information code. After copying, all the marks will have the same optical characteristics.

Abstract: A product provided with a coding pattern which comprises a plurality of marks, each of which represents one of at least two different values, and which further comprises a plurality of nominal positions, each of said plurality of marks being associated with a nominal position and the value of each mark being determined by its location relative to its nominal position. The invention also comprises use of the product.

Abstract: A method aims at identifying, starting from objects in a digital image, a virtual raster included in a coding pattern. The objects in the image at least partially reproduce marks on a base, each mark being associated with a respective point of intersection of raster lines belonging to the virtual raster. The method comprises the steps of matching sets of objects against a cell unit, which corresponds to a recurring known basic element of said raster; when a set corresponds with the cell unit, identifying the objects in the set as approved; and reconstructing the virtual raster on the basis of the mutual arrangement of the approved objects. A computer program, a storage medium and a device for position determination are also described.

Abstract: In an information management system for handling digital position data recorded by an electronic pen, the pen is designed to operate essentially independently of other system components. The pen is controlled to incorporate the position data into a data file object suitable for storage in a file system, and to expose the file object to an external data handler. The data file object may then be transported in the system from the external data handler in a sequential chain of transfers, with each transfer being independent of other transfers. The pen may be controlled to convert recordings of a first code on a product to one or more absolute positions in a coordinate system, to convert recordings of a second code to data indicative of a functional layout of the product, the data defining one or more functional areas in the coordinate system, and to map the absolute position(s) against the data to identify if the absolute position(s) falls within the functional area(s).

Abstract: An optical sensor device has an illuminating light source and an image sensor. The image sensor captures a sequence of images under exposure of light from the light source. A controller in the optical sensor device has a control output and generates an exposure time control signal on the control output. The controller includes an exposure time control loop. Each iteration of the loop includes the steps: calculating an error between a set value and an actual luminance condition value determined in a current image in the sequence of images; calculating a current exposure time as a function of the error and an exposure time calculated during the preceding iteration of the control loop; and generating the exposure time control signal on the control output based on the current exposure time. The exposure time may thereby be determined so as to yield optimum contrast in an image which is to be captured by the image sensor.

Abstract: A method and a corresponding device for generating true random numbers for use in encryption of a message for secure transmission of said message from a sending device to a receiver, or for authentication of a sent message. An optical image represented by optical data is obtained by an optical sensor and processed in order to improve the stochasticity of the optical data. The thus processed data is then used for generating random numbers which can be used as an encryption key, or for generating an encryption key, for subsequent use in an encryption algorithm for encrypting the message. The method is implemented in a digital pen (DP) to be used in an information management system.

Abstract: The invention relates to a method, a computer program product and a device for arranging a first and a second coordinate area relative to each other, which first and second coordinate areas are coded on a first and a second surface by a position-coding pattern. The method comprises the steps of receiving an electronic representation of a continuous line that has been drawn over the surfaces while the position-coding pattern on these was recorded, and creating an association between the first and second coordinate areas, based on a direction in which the line was drawn over a discontinuity in the Position-coding pattern, a first association being created if the line was drawn in a first direction and a second association being created if the line was drawn in a second direction.