초록 ▼

An infrared detector comprises an envelope in which a detector element (3) is mounted on an end of a cold finger (1). A chemically-active getter (30) is present in the space between the cold finger (1) and the envelope window (7) and outer wall (2). In accordance with the present invention the gette

An infrared detector comprises an envelope in which a detector element (3) is mounted on an end of a cold finger (1). A chemically-active getter (30) is present in the space between the cold finger (1) and the envelope window (7) and outer wall (2). In accordance with the present invention the getter comprises a porous layer (30) of chemically-active getter material deposited on an inside surface area of the outer wall (2) at a location separated from both the cold finger (1) and the window (7). The getter (30) can be activated (or re-activated) by heating through the portion of the outer wall (2) on which the getter material (30) is deposited, e.g. using a heater coil (50). Preferably the getter material (30) on the outer wall (2) extends around heat reflector, e.g. a reflective surface area of the cold finger (1). The cold finger (1) may be operated to cool the detector element (3) while heating the layer ( 30) to activate the getter.

대표청구항 ▼

An infrared detector comprising an envelope, a cold finger in the envelope and at least one detector element mounted on an end of the cold finger so as to be cooled by the cold finger in operation of the detector, the envelope having an outer wall extending around the cold finger and an infrared-tra

An infrared detector comprising an envelope, a cold finger in the envelope and at least one detector element mounted on an end of the cold finger so as to be cooled by the cold finger in operation of the detector, the envelope having an outer wall extending around the cold finger and an infrared-transmissive window facing the detector-element end of the cold finger, a space being present between the cold finger and the window and outer wall of the envelope, and a chemically-active getter present in said space to getter gases from the space, characterised in that the getter comprises a porous layer of chemically-active getter material deposited on an inside surface area of the outer wall at a location separated from both the cold finger and the window.