公开(公告)号：US3873782A

公开(公告)日：1975-03-25

申请号：US33087773

申请日：1973-02-08

Applicant: RCA CORP

Inventor： PALMER RICHARD CLAXTON

IPC: G11B9/06 ,  G11B3/46 ,  G11B9/07 ,  H04N5/92 ,  G11B3/44

CPC classification number: G11B3/46 ,  G11B9/075

Abstract: To protect a playback stylus against arcing, a relatively small value capacitance is provided in series circuit relationship with the stylus electrode. This capacitance limits damaging charge flow through the stylus electrode from the record medium surface.

Abstract translation: 为了保护重放触笔免受电弧放电，提供了与触针电极串联电路关系的相对较小的电容值。 该电容限制了从记录介质表面穿过触针电极的损坏电荷流。

公开(公告)号：US3930117A

公开(公告)日：1975-12-30

申请号：US52331174

申请日：1974-11-14

Applicant: RCA CORP

Inventor： CLEMENS JON KAUFMANN ,  PALMER RICHARD CLAXTON

IPC: G11B3/46 ,  G11B9/07 ,  H04N5/92 ,  H04N5/76

CPC classification number: G11B9/075 ,  H04N5/9204

Abstract: A stylus support element of dielectric material (e.g., sapphire) has a tip formed with a tapering, flat rear face, having converging straight edges which terminate in a curved bottom edge. Sides of the support element tip extend in converging fashion toward a narrow stylus front, while a curved surface, extending forward from the bottom of the rear face with a gradually diminishing width, forms the bottom of the support element. The rear surface of the support element is coated with a thin layer of conductive material (e.g., hafnium) which forms a stylus electrode. Overlying the conductive layer is an additional layer of dielectric material (e.g., aluminum oxide) having a thickness which is large relative to the thickness of the conductive layer, but small relative to the length of the curved bottom of the stylus support element. In use of the stylus in video disc playback apparatus, the stylus tip is received in the groove of a disc having a conductive surface covered with a dielectric coating. As geometric variations of the groove bottom, representative of recorded picture and sound information, pass beneath the stylus, the capacitance between the stylus electrode and the disc''s conductive layer varies. The capacitance variations are converted to electrical signal variations representative of the recorded information. Presence of the dielectric overcoating on the stylus electrode establishes a degree of symmetry for the stylus response, that eliminates or reduces spurious effects of sound interference with picture information that may be encountered in the absence of the overcoating use.

Abstract translation: 电介质材料（例如，蓝宝石）的触笔支撑元件具有形成有锥形的平坦后表面的尖端，其具有终止于弯曲底部边缘的会聚的直边缘。 支撑元件尖端的边缘以会聚的方式朝向窄的触针前端延伸，而从背面的底部向前延伸并且逐渐减小的宽度的曲面形成支撑元件的底部。 支撑元件的后表面涂覆有形成触针电极的导电材料（例如铪）的薄层。 覆盖导电层是介电材料（例如，氧化铝）的附加层，其厚度相对于导电层的厚度大，但相对于触针支撑元件的弯曲底部的长度较小。 在使用视频光盘播放装置中的触控笔时，触控笔尖被接收在具有覆盖有电介质涂层的导电表面的盘的凹槽中。 由于表示记录图像和声音信息的凹槽底部的几何变化通过触针下方，触针电极和盘的导电层之间的电容变化。 电容变化被转换成表示记录信息的电信号变化。 在触针电极上存在电介质涂层可以确定触针响应的对称程度，消除或减少在没有外涂使用时可能遇到的图像信息的声音干扰的杂散效应。