Compact integral Stirling linear cryocooler

An integral cryocooler comprising:

• a cold finger within an elongated space defined inside an elongated housing, wherein a tip of the cold finger freely protrudes outside an opening at an exterior end of the elongated housing, and wherein a root of the cold finger is supported in a cantilevered manner at an interior end of the elongated housing;
• a cryocooler cover sealingly connected to the elongated housing to form a pressure vessel;
• a ferromagnetic mover coaxially fixed to a movable capped cylinder that is located within the pressure vessel and surrounds the interior end of the elongated housing to form a compression space;
• and
• a stator, located outside the pressure vessel and comprising two cylindrical permanent magnets with opposite and axial magnetization surrounding a driving coil, such that when an alternating electrical current flows through the driving coil, the movable capped cylinder is moved axially back and forth to alternately compress and expand the compression space.