KTNC - Optical zoom block - Rolling Shutter 2mp

The rolling shutter is often perceived negatively and commonly associated with issues. However, this mechanism, also known as the "rolling shutter," is primarily an image acquisition system used on CMOS sensors.

Understanding the rolling shutter requires examining sensor technologies. These technologies are generally divided into two main categories: CMOS and CCD. CCDs expose the entire photosensitive surface at once. After exposure, the sensor is then closed to transfer electric charges to the reading areas. Although this process, known as the global shutter, is suitable for CCD technologies, it proves to be less effective with CMOS sensors found in our cameras and digital devices, as they are less light-sensitive.

To reduce the duration of photodiode occlusion, a method of line-by-line reading (from top to bottom of the sensor) is implemented. After reading each line of photodiodes, it can be exposed again more quickly.

It is worth noting that this technical limitation is not inherently linked to CMOS technology, but rather arises from technical decisions and economic considerations. Indeed, CMOS sensors with global shutter have been available for some time for industrial applications. However, these require an increased number of transistors per photodiode, resulting in increased production complexity and costs.

All models of KTnC Rolling Shutter optical blocks (click on the part number to download the datasheet):