CMOS image sensor with tunable dynamic range for catheter based endoluminal applications

Abstract A custom CMOS image sensor designed for catheter based visible and Near-Infra-Red (NIR) endoluminal applications is proposed. The sensor presents high dynamic range (HDR) capability in a controlled light environment, providing a user-programmable power responsivity curve. The fabricated chip is a monochrome imager including a 256 × 256 pixel array, a complete read-out channel, a series of DACs for internal references and digital blocks for chip control. The complete functionality of the chip is guaranteed through six signal pins, used for the I2C-like input interface and the differential analog output. Prototypes were produced using the AMS 0.35 μm OPTO technology. The imager was electrically and optically characterized. Characterization results show state-of-the-art performance in terms of pixel noise (PN