Harry, how on earth you are going to cool this "assembly" down? rhetorical question though. you can't is the answer, unless you shoot at a sub-zero temperature.
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Same way you cool GPU's down! Modern microchannel-based cooling pipes embedded into the either the chip substrate itself (i.e. licence some IBM patents) and/or use multi-phase vapour/phase change cooling within micro-sized heat pipes and copper plates that can FAST TRANSFER heat to the outer parts of a case AWAY from areas typically held by a user during phone calls and or when held in the hand. (i.e. expelled from vents or grills embedded into the bottom and top of the phone when held in portrait mode!)
At the speeds envisioned by using ARM-based Qualcomm 855 chips and 8192x6144 pixel or 50.3 megapixel sensors, you're looking at a maximum thermal design power of 5 to 6 watts for the Snapdragon 855 main processor and MANY image sensors are under HALF-A-WATT to as much as 3 watts for very high pixel count image sensors, so by using the extra phase-change cooling or microchannel cooling, it adds barely $60 US to the cost of the phone!
At those cheap prices for the IBM microchannel cooling patents, on a flagship phone with 50.3 megapixels, it's a FINANCIAL NO BRAINER to add the requisite cooling technology to support the added 6 to 8 watts of heat dissipation per required N-amount of time!
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The parent company I do consulting for, does this ALL THE TIME !!! Phase change cooling mostly with copper plates and heat pipes on the backs of the image sensors and copper or aluminum fins on the outside of the case costs us merely in design time and BARELY $25 to $100 US per device in patent licencing fees depending upon the imaging devices! For that measly amount of money, WHY should we care? We just ADD it to the end user price anyways (which is a LOT more than what a $1500 a Flagship supersmartphone costs!). $60 US out of $1500 retail forsuper-cooling technology is just chump change! As a manufacturer you take the money and eat it! Give the user what they want which is a Big Phone with Lots of RAM, a Powerful CPU/GPU and a BIG-SIZE 2/3rds inch 48-bit RAW and Compressed colour, low-noise, low-light-capable CMOS image sensor!
AND ... for Large 2/3rds inch and APS-C flagship smartphone and tablet designs, that $60 estimated patent licence fee for advanced cooling technology is a MERE drop in the bucket which can EASILY be passed onto the end-user anyways! AND ME AS THE END-USER could care less about an added $60 US when I get a super-smartphone with gigabytes of system RAM, and a Snapdragon 855 attached to a 2/3rds inch image sensor giving me 60 fps 8192 by 6144 16-bits per colour channel RAW or interframe compressed video AND 50.3 megapixel super-sharp RAW 48-bit colour stills that EXCEED the quality of a Canon 5Dr/s ALL at only $1500 US! Again, WHY should I care about companies licencing for 60 dollars worth of cooling technology added on to make me happy? I WANT TO BE HAPPY with my super-smartphone! Soooooooo, goto IBM and licence the embedded CPU and image sensor microchannel cooling technology AND/OR micro-sized multi-phase-change cooling tech!
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SO YES!!! You CAN cool this in a super-smartphone and since a 2/3rds inch sensor NEEDS about 12mm of thickness anyways for the focal plane issue, you just add the extra cooling within the available left-over 12 mm thick spacing, in addition to putting in extra-thick batteries for all-day use of those big sensors!
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