Vision Research announces the
Phantom v2010. The new 1MP camera is able to capture more than 22,000fps at full resolution or 1280 x 800. The camera is based on a custom-designed image sensor having 28um pixels. The pixels are said to have 12b "bit depth", not sure what it means. The sensor has a global shutter with fastest speed of 1us (standard version) or 500ns (export-controlled version). The physical size of the sensor is 35.8mm x 22.4mm.
A few questions hoping that someone could answer:
ReplyDelete-Do these high speed sensors use CDS?
-Analog or digital output?
-What type of pixel do they use (5T, 6T, 8T....?)
Thanks!
have you signed the NDA please :)- ??
ReplyDelete:D. The question was general and not necessarily related to this sensor ;)
DeleteProbably, these sensors will use the named false CDS. This CDS type remove the fixed or spatial offset noise, but cannot remove the temporal noise. But with a pixel as bigh as 28um, it is possible to include a local analogue memory per pixel to perform the true CDS.
DeleteIn relation with the output, probably is digital, because the anogue output at this very high speed is more difficult than the digital one. With a 28Gpixel per second. A single tab will need a data time of around 335ps. This is practically impossible. Even increasing the number of output by 100, the data time will be of 3.5ns, almost impossible jet. If 1000 output will be used, the data time will be 35ns, wich is very hard jet to transmit an a analogue signal, although is not impossible. But in this case 1000 A/D converters at 28MHz will be required.
From the allowed resolution selection, it looks like the readout is in 500 blocks of 128 x 16 pixels each. This is about 17 ns per pixel at full speed - still well within the range of a 12-bit ADC.
DeleteWith a 28 micron pixel and only 23.2k full well, there must be other stuff there, maybe even a slow ADC per pixel so only multiplexing is needed.
In another post some weeks ago we had a similar issue which did not get a clear answer. Why 12bit ADC for 57.9 dB DR? Especially in ultra high speed, high ADC resulution is very expensive. This is still a mistery for me..
DeleteFrom their website:
ReplyDelete•CMOS sensor
•1280 x 800 pixels
•28 µm pixel size
•35.8 mm x 22.4 mm
•12-bit depth
•TE and heat pipe cooled
•CAR in 128 x 16 increments
•ISO Monochrome 64,000T; 25,000D
•ISO Color 6,400T; 5,000D
•Dynamic range: 57.9dB
•Read out noise at 29.5°C (typical): 26e-
•Full well capacity: 23200e-
So, based on the info from their website... the answer to the original questions are:
ReplyDelete- No CDS is used - hence the noise is 26e- which is the kTC.
- Probably analog output
- most likely a 6T pixel since their mono ISO is so high - most of the pixel is likely collecting light.
Congrats to the team at Vision Research - 22 Gpix/sec output data rate is an impressive achievement.