FYI, all Foveon chips have done this. It is how the low resolutions images are quickly produced for the viewfinder. I suppose a lot of other CMOS chips do it also.
Actually, TPM does not assume the faster output speed. Rather, it stores the sequence of the frames in the pixel array and then reads the whole array out at the regular slow speed. The fast frame sequence is created by exposing the 1st, 2nd, 3rd, and so on groups of pixels with global shutter, whereas the shutter control speed rather than the readout speed defines the maximum frame rate.
Probably, I should have explained it better in the post.
So it uses global shutter technology to product a non-global shutter.
I suppose the light sensitivity is not great. Reading a large cell a million times a second gives a bit less than 1 us exposure on that large cell. With TPM, you get much smaller cells, though the exposure time can be a bit longer.
FYI, all Foveon chips have done this. It is how the low resolutions images are quickly produced for the viewfinder. I suppose a lot of other CMOS chips do it also.
ReplyDeleteActually, TPM does not assume the faster output speed. Rather, it stores the sequence of the frames in the pixel array and then reads the whole array out at the regular slow speed. The fast frame sequence is created by exposing the 1st, 2nd, 3rd, and so on groups of pixels with global shutter, whereas the shutter control speed rather than the readout speed defines the maximum frame rate.
DeleteProbably, I should have explained it better in the post.
So it uses global shutter technology to product a non-global shutter.
ReplyDeleteI suppose the light sensitivity is not great. Reading a large cell a million times a second gives a bit less than 1 us exposure on that large cell. With TPM, you get much smaller cells, though the exposure time can be a bit longer.
@ So it uses global shutter technology to product a non-global shutter.
DeleteIt uses a global shutter technology to produce a series of global shutter images, each one of them using a subset of pixels in the array.