I like this Thanko Notebook Tripod Stand, it gets your stupid leg-burning laptop off your lap and onto an ergonomic and adjustable surface. Sure it’s just an aluminium plate with a 1/4″ tripod thread and air vents, but it’s probably got a million uses; books, computers, sheet music, notebook holder. Might even come in handy if you shoot with a PC tethered to your camera. Even comes with a couple of Velcro straps to make sure your PC stays where you put it. ~US$21 (¥1980) but doesn’t come with the tripod.
We use commercially available camera tripod, just note that for fine height adjustment of the camera made the PC used as a convenient height adjustment. Adjust the side of the sofa legs longer, and set up a mini desktop PC. When the vehicle and adjust the length of the short legs and a mini in the car or use it as an alternative desktop PC.