A hermetic optical fiber feedthrough assembly (10, 60, 110), comprising: a first ferrule portion (40, 40', 140) having a first surface defining at least a groove (34, 34', 34", 134) receiving at least an end section of an optical fiber (24, 124), wherein the groove defines the location and orientation of the end section with respect to the first ferrule portion, and wherein the first surface of the first ferrule portion is provided with a first well defining a first pocket in the first ferrule portion; a second ferrule portion (42, 42', 142) having a second surface facing the first surface of the first ferrule portion, wherein the second surface of the second ferrule portion is provided with a second well defining a second pocket in the second ferrule portion, wherein the first pocket of the first ferrule portion and the second pocket of the second ferrule portion together define a cavity between the first ferrule portion and the second ferrule portion, wherein the cavity is wider than the groove, wherein a suspended section of the optical fiber is suspended in the cavity, and wherein an aperture is provided in at least one of the first ferrule portion and the second ferrule portion, exposing the cavity, wherein the first ferrule portion is hermetically attached to the second ferrule portion with the first surface towards the second surface, wherein the cavity is sealed with a sealant fed through the aperture with the sealant extending around the suspended section of the optical fiber within the cavity, thereby to hermetically seal at least a section of the optical fiber within the hermetic optical fiber feedthrough assembly, wherein the first ferrule portion includes an extended portion beyond an edge of the second ferrule portion, on which the groove extends and terminates at an optical element located beyond the edge of the second ferrule portion, wherein an end face of the optical fiber is located at a predetermined distance from the optical element along the axis of the optical fiber, and wherein the groove accurately aligns the optical fiber with respect to the optical element, so that output light from the optical fiber can be directed by the optical element in a direction away from the first surface of the first ferrule portion to outside the first ferrule portion or input light from outside the first ferrule portion incident at the optical element can be directed towards the optical fiber. a first ferrule portion (40, 40', 140) having a first surface defining at least a groove (34, 34', 34", 134) receiving at least an end section of an optical fiber (24, 124), wherein the groove defines the location and orientation of the end section with respect to the first ferrule portion, and wherein the first surface of the first ferrule portion is provided with a first well defining a first pocket in the first ferrule portion; a second ferrule portion (42, 42', 142) having a second surface facing the first surface of the first ferrule portion, wherein the second surface of the second ferrule portion is provided with a second well defining a second pocket in the second ferrule portion, wherein the first pocket of the first ferrule portion and the second pocket of the second ferrule portion together define a cavity between the first ferrule portion and the second ferrule portion, wherein the cavity is wider than the groove, wherein a suspended section of the optical fiber is suspended in the cavity, and wherein an aperture is provided in at least one of the first ferrule portion and the second ferrule portion, exposing the cavity, wherein the first ferrule portion is hermetically attached to the second ferrule portion with the first surface towards the second surface, wherein the cavity is sealed with a sealant fed through the aperture with the sealant extending around the suspended section of the optical fiber within the cavity, thereby to hermetically seal at least a section of the optical fiber within the hermetic optical fiber feedthrough assembly, wherein the first ferrule portion includes an extended portion beyond an edge of the second ferrule portion, on which the groove extends and terminates at an optical element located beyond the edge of the second ferrule portion, wherein an end face of the optical fiber is located at a predetermined distance from the optical element along the axis of the optical fiber, and wherein the groove accurately aligns the optical fiber with respect to the optical element, so that output light from the optical fiber can be directed by the optical element in a direction away from the first surface of the first ferrule portion to outside the first ferrule portion or input light from outside the first ferrule portion incident at the optical element can be directed towards the optical fiber.