Robert Boschgmbh

Willy Buchs

Pierre Jeannin

Roland Cochard

Frieder Heizmann

Dieter Baas

Giovanni Odone

A playback apparatus for a storage disc permits improved damping of vibration of the storage disc normal to the plane of the disc. The playback apparatus includes a first disc and a second disc, where the storage disc can be positioned between the first disc and the second disc. A predetermined distance is provided between the storage disc and the first disc within a predetermined area. The area and the distance are selected so that when there is vibration of the playback at apparatus approximately normal to the plane of the disc with an acceleration not exceeding a predetermined value, there results an amplitude of a resulting vibration of an outside edge of the storage disc in relation to a mid point of the storage disc which is below a predetermined value.

Playback apparatus for a storage disc

A method is proposed which serves to control the focusing of a light beam, aimed at a rotating recording medium (,) for reading data, of a scanner (,) onto the recording medium (,) and the guidance of the light beam along the data tracks of the recording medium (,), each by means of a respective control circuit. The scanner (,) and the recording medium (,) are mounted on a fundamental substrate (,) in at least one housing (,), and the at least one housing (,), together with the fundamental substrate (,), the scanner (,) and the recording medium (,), forms a coupled mechanical oscillator, which is vibrated as a function of a vibration spectrum (,); the scanner (,) is accelerated by the vibration and a relative motion of the recording medium (,) with respect to the scanner (,) is effected, and the amplitudes of the relative motion and the accelerations have a frequency response. The masses, spring constants and damping values of the scanner (,), the recording medium (,), the fundamental substrate (,), and the at least one housing (,) are selected such that the frequencies at which the amplitudes of the relative motion of the recording medium (,) relative to the scanner (,) and the accelerations acting on the scanner (,) are maximal are located in a frequency band of the respective control circuit in which an amplification is performed, and the maximum values of the amplitudes in that frequency band do not exceed a predetermined value.

Method of regulating the focusing and guiding of a light beam

Compensation scale for measuring the weight or mass of an object

To measure the distance to a selected object, the range finder transmits infrared light in a beam having a straight limiting edge on one side. The object reflects light back from the illuminated region and a lens receives part of the light and creates an image of the illuminated region including the straight limiting edge on a plane inclined at an angle to the optical axis of the lens. A detector, including a photoelectric transducer part of which is masked by a mask having a straight edge, is moved along the plane until the edge of the mask and the edge of the image are aligned as closely as possible. The position of the detector when this alignment takes place is indicative of the distance of the object from the range finder.

Growing community of inventors

Lonay, Switzerland

Willy Buchs