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 the 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. A method and device of using the product are also disclosed.

Abstract: A position code is applied on a surface to code positions in one or more directions. The code is based on a main number series which has the property that the place in the main number series of each number sequence of a first predetermined length is unambiguously determined. A position is determined based on one or more such number sequences of the first predetermined length. The orientation of the position code is discriminable from the main number series, but only for number sequences of a second predetermined length that exceeds the first predetermined length.

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: 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, 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: A method aims to identify a virtual raster pattern in an image of a surface that is provided with a plurality of position-coding marks. Each mark is associated with a respective intersection of raster lines belonging to the raster pattern. By means of the method, the virtual raster pattern is identified via Fourier analysis of the image. A computer program product and a device for position determination are also described.

Abstract: A method of providing a position code on a surface, which position code codes a plurality of positions on the surface. A cyclic number series is used, which has the characteristic that the position in the number series of each number sequence of a first predetermined length is determined unambiguously. The number series is printed out a plurality of times across the surface, different rotations of the first cyclic number series being used so that displacements arise between adjacent number series. The surface is divided into a plurality of code windows, which comprise at least three number series and have one number series overlapping one number series of adjacent code windows. The position of the code windows in the x-direction is coded by means of the displacements between the cyclic number series belonging to the code window. A second number series is used for coding in the y-direction.

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: The divider is composed of a number of strips, at least one of which extends longitudinally and another of which extends transversely. The strips have slots for interconnecting the strips. Each slot is defined by spaced apart side edges which extend generally vertically from the top edge of the strip to an intermediate portion and which extend further to a terminal portion. Each strip has a thickness which is greater than the distance which separates the side edges of the slot in the intermediate portion but which is less than the distance which separates the side edges of the slot in the terminal portion.

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 of providing a position code on a surface, which position code codes a plurality of positions on the surface. A cyclic number series is used, which has the characteristic that the position in the number series of each number sequence of a first predetermined length is determined unambiguously. The number series is printed out a plurality of times across the surface, different rotations of the first cyclic number series being used so that displacements arise between adjacent number series. The surface is divided into a plurality of code windows, which comprise at least three number series and have one number series overlapping one number series of adjacent code windows. The position of the code windows in the x-direction is coded by means of the displacements between the cyclic number series belonging to the code window. A second number series is used for coding in the y-direction.

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 and a device for determining a virtual raster of a code pattern consisting of a plurality of marks with associated coordinates mn. Each mark is located at a nominal position but displaced from the nominal position in one of a plurality of directions, depending upon the value of the mark. The nominal positions form raster points gn of the virtual raster, and the raster points are situated on raster lines, which intersect at a first angle. In addition there is a device for determining an initial vector V1,2 on the basis of the coordinates m1, m2 of one or more marks, which initial vector extends approximately between a first and a second adjacent raster point g1, g2. A calculation device determines a second vector V2,3, which forms said angle with the first vector and is the same length as the first vector and extends from the second raster point g2 approximately to a third raster point g3. The mark coordinate m3 which is associated with the third raster point g3 is determined.

Abstract: A method aims to identify a virtual raster pattern in an image of a surface that is provided with a plurality of position-coding marks. Each mark is associated with a respective intersection of raster lines belonging to the raster pattern. By means of the method, the virtual raster pattern is identified via Fourier analysis of the image.

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.