Integrated Circuits and Materials

CMOS (Complementary Metal-Oxide-Semiconductor) image sensors have emerged as an important technology in digital imaging, driven by the demand for compact and integrated solutions across consumer and industrial applications. Unlike traditional charge-coupled devices (CCDs), CMOS sensors allow for the integration of sensing capabilities with both analog and digital processing at the pixel level. This integration is advantageous for applications that require high-speed image capture, efficient power usage, and compact designs, making CMOS sensors an ideal choice for devices such as mobile phones, digital cameras, and video conferencing systems. CMOS sensors support functionalities like auto-focus and image compression within the same chip, further reducing power and space requirements.

A typical CMOS imaging system pipeline begins with light focused onto a sensor through optics, where an array of pixels converts the incident light into electrical signals. In color imaging, a color filter array (CFA) is used to capture color information at each pixel, which is processed by an analog-to-digital converter (ADC) to digitize the signal. CMOS sensors use pixel-level processing to achieve high-speed readout and minimize power consumption, enabling high-resolution and dynamic range imaging. While CCDs have advantages in certain aspects like minimal temporal noise and higher low-light performance, CMOS sensors excel in versatility, making them a strong alternative for various advanced imaging applications.

Figure 0147 shows a CMOS image sensor pixel array with color filters and microlenses.