Patent ID: 8343042

Claim:
An endoscopic coupler for relaying an image formed at the distal end of an endoscope to a detector located downstream of the coupler, said coupler comprising: a hermetically sealed housing having transparent entrance and exit windows arranged along an optical axis; a lens cell slidably mounted for translation in said hermetically sealed housing along said optical axis; a lens mounted within said lens cell for receiving light through said entrance window and imaging it through said exit window and onto the detector; a focusing ring mounted outside of said hermetically sealed housing for relative rotation with respect thereto; a mechanical arrangement located within said hermetically sealed housing and adapted to translate said lens cell to move said lens along its axis; a first continuous plastic cylindrical tubular magnet fixedly mounted to said focusing ring for movement therewith as said focusing ring is rotated, said first continuous plastic cylindrical tubular magnet comprising a plastic binder having magnetic powder distributed throughout and aligned as continuous magnetic poles that alter in polarity around the circumference of said first continuous plastic cylindrical tubular magnet but do not alter in polarity along its axial length; and a second continuous plastic cylindrical tubular magnet mounted inside of said hermetically sealed housing for relative rotation with respect thereto, said second continuous plastic cylindrical tubular magnet also comprising a plastic binder having magnetic powder distributed throughout and aligned as continuous magnetic poles that alter in polarity around the circumference said second continuous plastic cylindrical tubular magnet but do not alter in polarity along its axial length, said second continuous plastic cylindrical tubular magnet being configured and arranged to rotate as said focusing ring is rotated and being coupled to said mechanical arrangement so that the rotary motion thereof causes said lens cell to translate along the axis of said lens to focus it.