Improved Image Sensor for Outdoor Security & Surveillance cameras
A Finnish company has developed a new image sensor technology based on patented MIG (Modified Internal Gate) pixel architecture. The technology allows non-destructive image read-out, which offers significant advantages for image recognition in low-light situations.
A Finnish company has developed a new image sensor technology based on patented MIG (Modified Internal Gate) pixel architecture that increases sensitivity and image quality in security & surveillance cameras.
In security & surveillance camera applications identification is generally performed from a stored video stream. In low light, however, the image quality of single video frames is often too poor for identification. In order to improve the image quality one should look in the stored video stream for periods when the subject remains more or less still over several frames.
By merging frames together during such a period image quality and consequently identification can be improved considerably. When frames are merged together Modified Internal Gate (MIG) image sensor technology enables much better image quality than conventional image sensor technologies. This is due to the fact that the signal in MIG sensors can be readout accurately in a non-destructive manner whereas in CMOS Image Sensors (CIS) or Charge Couple Devices (CCD) accurate readout is always destructive, i.e., the signal is always destroyed.
Innovations & Advantages
MIG architecture provides superior low light image quality when compared to any other image sensor technology. In figure 1, below, simulated images of merged frames are presented for MIG and high-end CMOS Image sensors.
A great benefit of the MIG sensor is that no frame rate optimization is required since the sensor can always be operated with maximum reasonable frame rate without impeding the image quality, unlike the traditional sensors. Moreover, MIG sensor cannot be distracted with bright light sources.
The manufacturing of MIG image sensors is compatible with existing CMOS processes enabling the readout and digital logic circuitry as well as the MIG pixel matrix to be incorporated into the same chip.
Current and Potential Domains of Application
Security applications in low-light situations.