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Your problem is physics related. What you are asking for is a camera and lens that have a depth a focus from some minimum out to infinity. such that the target will never be closer than the minimum focus. Of course this can be done but there is a trade off.

A camera that has a wide depth of focus will have three features you may not want: A wide angle lens, physically small sensor size and numerically high f-stop number. I camera like this typically has poor low light performance and has a bit of "noise" or grain in the image. Most of the things engineers can do to improve the image alto reduce the depth of focus. They make up for this by using a focus motor on the lens. So it is a trade off, one thing for another.

One way you can solve the grain and noise problem is by seriously increasing the amount of light. Double the lighting power for every loss of 1 f-stop. A fixed focus lens operating at (say) f/5.6 needs 4 times as much light as the same lens at f/2.8 and 8 times as much as one at f/2.0 Image quality improves quite a lot as you add light, does wonders for the signal to noise ratio (because you are adding signal)

You also have a limit if you are using a USB 2 interface to the camera. You can't get uncompressed 1080P at 60 fps trough a USB cable. USB lacks the required bandwidth.

All that said. A good solution is the USB web cam that was made for the Sony Playstation II It was VERY inexpensive, under $10. They are used by many people for computer vision, especially video because that can to 480P at 60 fps. They are fixed focus and there is a two step manual zoom but even the wide setting is not very wide. This will be a problem if used for survilence. You would need to attach an auxiliary lens There is also a good quality microphone array on the camera.

wikipedia.org/wiki/PlayStation_Eye