A sensor for thermal patterns, of the pyroelectric sensor type, including a contact surface (271; 571; 771) to apply an object to be imaged thereto, in particular a fingerprint, and a plurality of pixels (200; 400; 500; 600; 700; 800) distributed between a substrate (210; 510; 710; 910) and said contact surface (271; 571; 771), characterised in that each pixel comprises: - at least one charge collecting electrode (260; 460; 560A; 760A; 860); - a first structure, including a first portion (250A; 450A; 550A; 750A) comprising a pyroelectric material, said first structure being in direct physical contact with one from the at least one charge collecting electrode (260; 460; 560A; 760A; 860); - a second structure, including a second portion (250B; 450B; 550B; 750B) comprising a pyroelectric material, said second structure being in direct physical contact with one from the at least one charge collecting electrode (260; 460; 560A; 760A; 860), with the first structure, the second structure, and the at least one charge collecting electrode that are superimposed above the substrate and arranged so that each pixel includes two superimposed pyroelectric capacitors, where each pyroelectric capacitor includes, at least, the one portion comprising a pyroelectric material and the one charge collecting electrode, and with both pyroelectric capacitors sharing a same charge collecting electrode or a same reference electrode; - at least one heating element (220A, 220B; 420A, 420B; 520; 720A, 720B; 820), to heat the first and second portions comprising a pyroelectric material; and - an electronic device (280; 580) connected to the at least one charge collecting electrode, and configured to measure a difference between charges generated by one from the first and second portions comprising a pyroelectric material, and charges generated by the other from the first and second portions comprising a pyroelectric material. - at least one charge collecting electrode (260; 460; 560A; 760A; 860); - a first structure, including a first portion (250A; 450A; 550A; 750A) comprising a pyroelectric material, said first structure being in direct physical contact with one from the at least one charge collecting electrode (260; 460; 560A; 760A; 860); - a second structure, including a second portion (250B; 450B; 550B; 750B) comprising a pyroelectric material, said second structure being in direct physical contact with one from the at least one charge collecting electrode (260; 460; 560A; 760A; 860), with the first structure, the second structure, and the at least one charge collecting electrode that are superimposed above the substrate and arranged so that each pixel includes two superimposed pyroelectric capacitors, where each pyroelectric capacitor includes, at least, the one portion comprising a pyroelectric material and the one charge collecting electrode, and with both pyroelectric capacitors sharing a same charge collecting electrode or a same reference electrode; - at least one heating element (220A, 220B; 420A, 420B; 520; 720A, 720B; 820), to heat the first and second portions comprising a pyroelectric material; and - an electronic device (280; 580) connected to the at least one charge collecting electrode, and configured to measure a difference between charges generated by one from the first and second portions comprising a pyroelectric material, and charges generated by the other from the first and second portions comprising a pyroelectric material.