- Reproducibility : will give quantitative information about how well particular measurements and retrieved performance data do reproduce if the devices are measured over and over again by means of the same calibrated measurement equipment,
- Variability : will give quantitative information about the spread of the performance data from sensor to sensor/from camera to camera,
- Reliability : will give quantitative information about the stability of the sensor and camera performance over time.
The measurements will be performed on a higher-end, more expensive camera with a global shutter CMOS sensor and on a lower-end, cheaper camera with a rolling shutter CMOS sensor. The cameras will be thoroughly measured every 6 months over a period of 5 years, from 2017 to 2021.
Will the sensors be stressed/used between measurements or is this just a static age test? What's the goal here, check reliability and stability of the sensor or the measurement system? Why not use an oven/humidity chamber instead of passing of time? If the passing of time is the only stressor here, not very interesting, there's not a lot of things to age in the silicon, it's not like it's bread.
ReplyDeleteFirst, just passing of the time allows us to estimate the sensors shelf life. Many sensors, like ones in the consumer cameras, are powered off most of their life.
DeleteSecond, the accelerated aging is a good tool to estimate reliability, but not so good to see how sensor really changes over time. Like color filters fading probably accelerates differently from the image lag in photodiodes, for example.
So, it's going to be quite interesting research. I'd guess this data might be collected in places that check long term image sensor effects, like space research organizations. But so far, I have not seen it available for general public.
In the text on the webpage it is mentioned :
DeleteIn a second stage of the reliability, starting after one year (= after 3 measurement cycles), the sensors will be extra stressed, such as :
Temperature – humidity stress at 85 °C – 85 % humidity,
Stored under UV-light to test the stability of the colour filters,
Exposed to gamma-rays,
Exposed to cosmic rays at higher altitudes,
….
Subsequent measurement cycles will give quantitative data about the reliability of the sensors under harsh conditions.
Apparently you did not read the complete text ....
Mr./Mrs. Anonymous, please fill out the small form on the website (www.harvestimaging.com/newproject.php) and you will get all answers to your questions.
ReplyDeleteThis could be even more interesting if these are included
ReplyDelete- Test on a monochrome imager, especially of QE (etaloning) stability
- Test on a camera working continuously with 70 -80 % duty cycle, with a light source (for long term burn-in test, and development of new defects)