The mounting screws of most cameras are unified with tripod screws.
It usally called “Camera screw”, “tripod screw”
There are few differences between manufacturers and types of cameras.
The screw size is 1 / 4-20 UNC (1/4 inch coarse).
The screw diameter is about 6 mm.
There is no difference in single lens reflex cameras, small digital cameras, surveillance cameras, FA cameras..
The mounting screws shown in the bottom photo are all the same size.
With a small camera or an old camera, it may be used 3 / 8-16 UNC (3/8-inch coarse) The screw diameter is about 9 mm.
You can prepare a screw for camera fixing, but fixtures are also sold in various ways for both civilian and industrial.
Since the angle can be changed. Thus, it is one more way to use existing products.
Since it is a standard screw for the camera, you can use commercially available camera (tripod, pan head etc).
Since various conversion screws of 1/4-inch ⇔ 3/8-inch are available, tripods can be used even if the screw diameters are different.
Examples of camera fixing devices
Below is a part of LPL’s catalog.
・Examples of industrial camera fixtures
The following is a part of the catalog of SFC Co., Ltd.
If the lens is long and heavy, there are also lens mounts
(All our lenses for microscope are φ50 mm (fixed part)