Development of a multifunctional CMOS image sensor for in vivo sensing of neural activities in a mouse deep brain

Abstract

We developed a multimodal CMOS image sensor includes an pixel array, electrodes, and LED. The electrodes were placed on the pixel array. Windows were opened in the electrode over the photodiodes to enable the fluorescence to be imaged using the pixels under the electrodes. An LED was mounted on the chip for miniaturization and the sensor chip was shaped like a shank to facilitate smooth insertion into the brain tissue. In a brain phantom, the change in the electrical potential was successfully sensed by the electrode, and green fluorescent beads were simultaneously imaged using the pixels under the electrode. We also demonstrated that the device could successfully operate in deep brain of an anesthetized mouse.