HS system in SLR's?
One of the important components in the Canon HS system is a BSI-CMOS sensor. The Back Side Illuminated sensors are very efficient in the small sensor P&S cameras when otherwise a substantial portion of the tiny active diode area is taken up with interconnect.
BSI solves this problem by lapping the chip very thin so that the diode junctions are reached, then flipping the chip over so that the interconnect is now on the back side of the chip, and the old back side of the chip is now the top side where it gets the image light from the lens.
On a larger DSLR chip, this is not practical for two reasons: 1) The diodes are already so large that negligible additional area would be gained by this technique. Micro lenses perform the same function more cheaply. And 2) Thinning a large chip would make it so fragile that the yield would be extremely low, both from lapping accuracy and chip breakage, driving the cost very high.
As a result, there is very little reason to attempt BSI-CMOS for large chips, making the HS system unlikely in large DSLR CMOS sensors.
Looking to purchase a T3i, but was wondering if anyone knew if & when the HS system would be available in the Mid-level models?
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