The present invention relates to a bolometer (10) comprising a substrate (12), a first membrane (16) formed by removing a first sacrificial layer (14) on the substrate (12), the first membrane (16) comprising a measuring element (18) for measuring an amount of incident electromagnetic radiation (R), a second membrane (22) formed by removing a second sacrificial layer (20) on the first membrane (16), the second membrane (22) enclosing the first membrane (16), a first cavity (24) formed between the substrate (12) and the first membrane (16), and a second cavity (26) formed between the first membrane (16) and the second membrane (22). The present invention further relates to a method of manufacturing a bolometer, as well as a thermographic image sensor and medical device.