The camera box shape let thinking that the CCD is mounted along the largest size of the camera box. According to the data found in this document, the maximun size of a picture is 4208x3120. When I take a picture, I get 4096x3072 which is a 4/3 ratio portrait. When I take a picture of the scene in front of me, the camera box is horizontal since my arm is too. However, the CCD dimensions are 6.1mm by 4.5 mm and it can also be mounted vertically in the camera box. My feeling is that the CCD is vertical since I can get maximum resolution taking a picture in portrait format.
The choice of the CCD orientation is questionable mostly when we want to use this CCD to take video of a landscape scene. I read in this forum that the maximum resolution for a video is 1920x1080 (about 2 MPixels) and that the CCD captor is not used at its maximum. In my opinion, this is not totally true. Here the “binning” concept could be a good explanation : the association of neighboring pixels is often used to increase the CCD sensitivity, especially when the light is low. Unlike in photography, to get a video at 30 fps it is not possible to vary the exposure time of each image. However, it is possible to increase the sensitivity by increasing the binning. Here, the maximum usable binning is 2x2 = 4 CCD pixels to form 1 pixel in the target image in the video. In that way, you can get a full HD video in low light condition using 4x1920x1080 = 8.3 MPixels. In this mode, only 13.1-8.3 = 4.8 MPixels are wasted. The next binning mode would require 3x3x1920x1080 = 18.7 MPixels which cannot be handle by the Optimus 2 camera.
In very low light condition, the camera automatically decreases the frame rate then increasing the exposure time of each image (like in photography).
I think the CCD use is well optimised but its orientation should be horizontal in the camera box. May be for an Optimus 3 version ? …