Abstract: A system for recording signals in a disc master comprises an electromechanical cutterhead responsive to the signals and a signal processing means interposed between the cutterhead and a signal source. The signals applied to the cutterhead are of the encoded type such that most of the signal energy is contained in signal components occupying a band of frequencies about one octave wide or less. The cutterhead is so constructed that its response to the signal components varies with frequency in substantial correspondence with the energy distribution of the maximum signal components over the afore-mentioned band. The signal processing means serves dual purposes. On the one hand, it cooperates with the cutterhead to provide a combined frequency response which is relatively uniform. On the other hand, it serves to reduce the energy level of high energy level signal components applied to the cutterhead.

Abstract: An unheated cutting stylus is positioned with respect to a metal master in order to cut a groove having a quiescent groove depth less than one micrometer while relative motion is established between the cutting stylus and the metal master. The cutting stylus is vibrated about the quiescent position thereof in response to a relatively high frequency signal while cutting the groove in order to cut an information track comprising short wavelength modulation (e.g., 0.6 to 1.6 micrometers) of groove depth in the bottom of the groove having a peak-to-peak dimension less than the quiescent groove depth. The cutting stylus vibration is effected by a piezoelectric element which is mounted directly between a pedestal and the cutting stylus by means of bonding materials. The pedestal, the piezoelectric element, and the cutting stylus are shaped to form a cutterhead structure having all external surfaces disposed in anti-parallel relationship to each other.

Abstract: An unheated cutting stylus is positioned with respect to a metal master in order to cut a groove having a quiescent groove depth less than one micrometer while relative motion is established between the cutting stylus and the metal master. The cutting stylus is vibrated about the quiescent position thereof in response to a relatively high frequency signal while cutting the groove in order to cut an information track comprising short wavelength modulation (e.g., 0.6 to 1.6 micrometers) of groove depth in the bottom of the groove having a peak-to-peak dimension less than the quiescent groove depth. The cutting stylus vibration is effected by a piezoelectric element which is mounted directly between a pedestal and the cutting stylus by means of bonding materials. The pedestal, the piezoelectric element, and the cutting stylus are shaped to form a cutterhead structure having all external surfaces disposed in anti-parallel relationship to each other.

Abstract: A cutterhead assembly suitable for forming a topographic signal-representative pattern in a recording medium such as a disc is constructed with non-parallel external surfaces so as to provide a response relatively free of undesired resonant modes over a relatively wide frequency range. The cutterhead includes a cutting stylus supported in a stylus mount. The stylus mount and therefore the stylus are driven by a piezoelectric element which is mounted on a supporting pedestal. A resilient mounting means is utilized to fasten the supporting pedestal to a mounting bracket.