Insulated electrocardiographic electrodes

Claim 1

An electrode for detecting bioelectric potentials comprising: a. housing means made of substantially non-electrically conductive material and having a flat outer surface portion; b. an electrically conductive substrate having a front face and a back face mounted in a fixed relationship to said outer surface portion of said housing means such that said substrate and said outer surface portion of said housing means are essentially parallel; c. a substantially non-electrically conductive dielectric material mechanically bonded to and completely covering said front face of said substrate by means of radio-frequency sputtering techniques and wherein said resulting substrate is mounted on said outer surface portion of said housing means such that said dielectric material will be in intimate contact with an external body when said electrode is placed thereon and said back face of said substrate is exposed to the internal environment of said housing means; d. electrically insulative encasing material extending continuously along and completely covering the edges of said substrate for preventing electrical current flow between said substrate and the external body; e. an impedance transforming means mounted within said housing means and electrically connected to said back face of said substrate for providing said electrode with a relatively low output impedance and a relatively high input impedance whereby the impedance of said electrode may be matched with and connected directly to conventional monitoring equipment having a relatively low input impedance; and, f. means for connecting said transforming means to the monitoring equipment.