Abstract: An optical input and/or control de and/or actuating variable functions of, for examp device, the optical input and/or control device ha radiation from a diode laser (3) is converged. As across the window (12), part of the scattered radi due to the movement of the finger (15), re-enters measured using the self-mixing effect of the lase radiation emitted by the laser (3) and re-entering of the laser and thus in the radiation emitted by photo-diode (4) which converts the radiation vari circuitry is provided which processes this signal. ice for manually selectively controlling e, an image capture device or a computer mg a transparent window (12) on which an object, e.g. a user's finger (15), moves tion, whose frequency is Doppler-shifted the laser cavity. Relative movement is diode (3), which is the phenomenon that e laser cavity induces a variation in gain e laser (3).

Abstract: Optical recording method and apparatus using this method. An optical recording method and recording apparatus using this method is described in which an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on an optical recordable medium, forming a read signal from the patterns, reading a preset value of the derivative of the modulation of the read signal with respect to the write power from the medium, and processing the read signal together with the preset value to derive an optimum value of the write power.

Abstract: An optical recording method and recording apparatus using this method is described in which an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on an optical recordable medium, forming a read signal from the patterns, reading a preset value of the derivative of the modulation of the read signal with respect to the write power from the medium, and processing the read signal together with the preset value to derive an optimum value of the write power.