(EP849802-A2)      The method involves coupling a first capacitor (C1) to a read-out circuit during first portion of read-out period which follows the integration period. A first potential resulting from integrated photocurrent of the first capacitor is stored and amplified. A second capacitor (C2) is coupled to the read-out circuit during second portion of read-out period.    A second potential resulting from integrated photocurrent of the second capacitor is subtracted from stored first potential to generate difference potential. The difference potential is then amplified.    ADVANTAGE -   Ensures simultaneous detection of infrared radiation in two spectral bands. Prevents spectral crosstalk in photocurrent signal. Reduces noise generation and circuit complexity.    (JP10281869-A)      The method involves coupling a first capacitor (C1) to a read-out circuit during first portion of read-out period which follows the integration period. A first potential resulting from integrated photocurrent of the first capacitor is stored and amplified. A second capacitor (C2) is coupled to the read-out circuit during second portion of read-out period.    A second potential resulting from integrated photocurrent of the second capacitor is subtracted from stored first potential to generate difference potential. The difference potential is then amplified.    ADVANTAGE -   Ensures simultaneous detection of infrared radiation in two spectral bands. Prevents spectral crosstalk in photocurrent signal. Reduces noise generation and circuit complexity.    (JP3187760-B2)      The method involves coupling a first capacitor (C1) to a read-out circuit during first portion of read-out period which follows the integration period. A first potential resulting from integrated photocurrent of the first capacitor is stored and amplified. A second capacitor (C2) is coupled to the read-out circuit during second portion of read-out period.    A second potential resulting from integrated photocurrent of the second capacitor is subtracted from stored first potential to generate difference potential. The difference potential is then amplified.    ADVANTAGE -   Ensures simultaneous detection of infrared radiation in two spectral bands. Prevents spectral crosstalk in photocurrent signal. Reduces noise generation and circuit complexity.