I have just basic understanding of Physics from elementary school. But I still wonder, why after 10 years of cameras in cellphones, there is no "small-pack" optical zoom.
I think there should be no problem to make small, but still precise lenses. It should not be a problem to make small light sensor, while keeping large resolution. It should not be a problem to make tiny electric motor or servomotor to move the lenses and pack all that into 1 cm x 1 cm x 0.5 cm packing.
So what is the problem? I think there may be 3 explanations:
There is some limit in physics (nature), that does not allow to do that (which one?)
There is some limit in engineering, which makes tiny optical zoom extremely expensive.
It might work, but nobody came yet with the idea to make tiny optical zoom.
Can you validate or disprove any of 1/2/3?