What size is 1/1.63"? Why can't we move away from this arcane way of expressing sensor size? My guess is, the sensor is still less than 6mm in height ...
According to a Panasonic site, the sensor has 2.00 micron cell size (is this the biggest in recent compact sensors?) and the total active pixel count is 3968x2736, though all its JPEG output options crop that to one of three different shapes from 3648x 2736 in 4:3 to 3968 x 2232 in 16:9. The output crops seems to be limited to the image circle diameter of the lens, at least at its wide end where the image circle is typically smallest.
Multiplying out gives
- sensor active area of 7.936x5.472mm, diagonal 9.64mm
- 4:3 format area of 7.296x5.472mm, diagonal 9.12mm
- slightly smaller diagonal and smaller image area for the other shapes (more elongated formats like 3:2 and 16:9 record less of the total image area within a given image circle.)
I would love this to be called a 9.6mm diagonal sensor (or a 7.9x5.5mm sensor, but one number is all that some camera buyers will swallow!), with the 4:3 crop called 9.1mm diagonal format and so on.
And I agree that the small sensor size probably limits the f/2-2.8 lens to less low light performance and DOF control than an f/4-5.6 lens in even the smallest DSLR format, but for the many compact cameras users seeking mostly images that are sharp across the frame (meaning with fairly substantial DOF), it could be appealing.
Aside: This is as close as we are likely to get to the recurring square sensor dream: expanding the sensor to a rectangle that covers the part of the image circle that fits all commonly used image shapes. This would be harder in an SLR, due to the mirror needed being larger than for any one output format.