Asynchronous laser pulse detection and passive imaging

An imaging device including at least one detection element formed of a photodetector associated with and connected to a circuit for reading signals generated by the photodetector, the circuit being provided with:

• an integration stage equipped with an integration capacitor for integrating charges coming from the photodetector,
• a pulse detection stage for detecting current pulses produced by the photodetector following the receipt of light pulses, and
• a bias stage of the photodetector and equipped with a direct injection transistor coupled to the photodetector,
• the readout circuit further being provided with a so-called “intermediate” stage arranged on the one hand between the bias stage and between on the other hand respectively the integration stage and the pulse detection stage, the intermediate stage being provided with transistors forming a current mirror provided with a branch coupled to a drain of the direct injection transistor and producing on an input branch of the integration stage an image current of a given current delivered by the direct injection transistor, the intermediate stage being configured to convert said given current into a potential on an input node of said pulse detection stage, said input node being arranged on a gate electrode or at a source electrode of a transistor of said intermediate stage.