Abstract: A method for applying illumination correction for an optical computer mouse, includes: flashing a light source of the mouse directed towards a surface; accumulating voltage on a pixel array of the mouse to obtain raw pixel values of an image frame in response to detecting light reflected from the surface; applying analog correction to the raw pixel values based on digital gain coefficients to obtain an array of corrected pixel values forming corrected image data; digitizing the corrected image data with an analog-to-digital converter to obtain digital pixel values forming digital image data; and updating the digital gain coefficients so that a gain coefficient corresponding to a digital pixel value is incremented if the digital pixel value is below or equal to a given pixel threshold value, and so that the gain coefficient is decremented if the digital pixel value is above the given pixel threshold value.

Abstract: A method for tracking a position of an optical computer mouse based on determining a spatial displacement between image frames. A respective image frame is considered as an anchor frame if the respective image frame comes first in a sequence of image frames or the distance of the respective image frame to its immediately previous anchor frame is equal to or greater than a displacement threshold, and the respective image is considered as an intermediate frame if its distance to its immediately previous anchor frame is below the displacement threshold. Only anchor frames are stored in memory and used for future displacement measurements between image frames captured by the mouse.

Abstract: A method of determining an absolute angle of a magnetic field includes receiving a first digital measurement value Bx of a first magnetic field component indicating intensity of the magnetic field along a first axis; receiving a second digital measurement value Bz of a second magnetic field component indicating the intensity of the magnetic field along a second axis, orthogonal to the first axis; determining absolute values for the first and second magnetic field components; and determining the angle of the magnetic field with respect to the first or second axis. The angle is determined so that the angle is derivable from the value of arcsin of Bz or of its approximation, when the absolute value of Bz? the absolute value of Bx, and derivable from the value of arccos of Bx or of its approximation, when the absolute value of Bz> the absolute value of Bx.

Abstract: A method of determining an absolute angle of a magnetic field includes receiving a first digital measurement value Bx of a first magnetic field component indicating intensity of the magnetic field along a first axis; receiving a second digital measurement value Bz of a second magnetic field component indicating the intensity of the magnetic field along a second axis, orthogonal to the first axis; determining absolute values for the first and second magnetic field components; and determining the angle of the magnetic field with respect to the first or second axis. The angle is determined so that the angle is derivable from the value of arcsin of Bz or of its approximation, when the absolute value of Bz? the absolute value of Bx, and derivable from the value of arccos of Bx or of its approximation, when the absolute value of Bz> the absolute value of Bx.

Abstract: The present invention relates to a method, to a computer program and to a system to establish wireless communication between at least two Bluetooth Low Energy (BLE) devices the method comprising the steps of: switching a first BLE device (20) into a scanning mode (SM), switching a second BLE device (30) into an advertising mode (AM), and broadcasting a first advertising packet (31) from the second BLE device, switching the second BLE device (30) into the scanning mode (SM), receiving the first advertising packet (31) by first BLE device (20), and switching the first BLE device (20) into the advertising mode (AM), and broadcasting a second advertising packet (21) from the first BLE device (30).

Abstract: The present invention relates to a method, to a computer program and to a system to establish wireless communication between at least two Bluetooth Low Energy (BLE) devices the method comprising the steps of: switching a first BLE device (20) into a scanning mode (SM), switching a second BLE device (30) into an advertising mode (AM), and broadcasting a first advertising packet (31) from the second BLE device, switching the second BLE device (30) into the scanning mode (SM), receiving the first advertising packet (31) by first BLE device (20), and switching the first BLE device (20) into the advertising mode (AM), and broadcasting a second advertising packet (21) from the first BLE device (30).