Biological systems are a source of inspiration in the development of small autonomous sensor nodes. The two major types of optical vision systems found in nature are the single aperture human eye and the compound eye of insects. The latter are among the most compact and smallest vision sensors. The eye is a compound of individual lenses with their own photoreceptor arrays. The visual system of insects allows them to fly with a limited intelligence and brain processing power. A CMOS image sensor replicating the perception of vision in insects is discussed and designed in this book for industrial (machine vision) and medical applications.

The CMOS metal layer is used to create an embedded micro-polarizer able to sense polarization information. This polarization information is shown to be useful in applications like real time material classification and autonomous agent navigation. Further the sensor is equipped with in pixel analog and digital memories which allow variation of the dynamic range and in-pixel binarization in real time. The binary output of the pixel tries to replicate the flickering effect of the insect s eye to detect smallest possible motion based on the change in state. An inbuilt counter counts the changes in states for each row to estimate the direction of the motion. The chip consists of an array of 128x128 pixels, it occupies an area of 5 x 4 mm2 and it has been designed and fabricated in an 180nm CMOS CIS process from UMC.

Biological systems are a source of inspiration in the development of small autonomous sensor nodes. The two major types of optical vision systems found in nature are the single aperture human eye and the compound eye of insects. The latter are among the most compact and smallest vision sensors. The eye is a compound of individual lenses with their own photoreceptor arrays. The visual system of insects allows them to fly with a limited intelligence and brain processing power. A CMOS image sensor replicating the perception of vision in insects is discussed and designed in this book for industrial (machine vision) and medical applications. The CMOS metal layer is used to create an embedded micro-polarizer able to sense polarization information. This polarization information is shown to be useful in applications like real time material classification and autonomous agent navigation. Further the sensor is equipped with in pixel analog and digital memories which allow variation of the dynamic range and in-pixel binarization in real time. The binary output of the pixel tries to replicate the flickering effect of the insect's eye to detect smallest possible motion based on the change in state. An inbuilt counter counts the changes in states for each row to estimate the direction of the motion. The chip consists of an array of 128x128 pixels, it occupies an area of 5 x 4 mm2 and it has been designed and fabricated in an 180nm CMOS CIS process from UMC.

CMOS image sensors (CIS) have come a long way from the late 1980s and early 1990s up to where they are today. However, already since the very first developments in the field, column-level single-slope analog-to-digital converters (SS-ADC) were incorporated. The combination of an image sensor with on-chip column-level ADCs demonstrates exceptional performance as far as speed and power are concerned. It is not only the imaging array that went through a lot of new developments, so did the SS-ADC configuration. This monograph gives an overview and background of the various developments of the SS-ADCs. In Part I, some background information is given about the general CIS architecture, the CIS pixels and the noise sources present in a CIS. Part of this general technical information is used in the remaining section. Part II describes the various architectures used in a SS-ADC, starting with the most simple and earliest device described to the more complex architectures that include additional features in the ADC. After the description of the overall structure of the SS-ADCs, in Part III more details are studied about the various building blocks that are used in the SS-ADCs, such as amplifiers, comparators, ramp generators and counters. The monograph concludes with a future outlook, included in Part IV.