French term (edited): pupitre portable tactile

If I were describing this in EN, I would probbaly naturally call it a '(control) console' — you could easily omit 'control' if the function is made clear elsewhere, e.g. "all lights are controlled from a portable console"

You might also refer to it as a 'desk' (sound desk, lighting desk) — though in the absence of further qualification, I think that does rather tend to conjure up images of a free-standing piece of furniture — though perhaps less so these days, where more and more models seem to be table-top designs.

--------------------------------------------------
Note added at 2 jours9 heures (2016-12-12 22:04:05 GMT)
--------------------------------------------------

The description given in the source text: « Il peut se poser sur un support à roulettes ..., ou au bras avec des sangles » seems to clearly indicate this is a comparatively larger device than a mere 'hand-held remote control'; the fact it can be strapped on the forearm suggests it might be some kind of 'tablet' device, and even if it were, I don't think 'control console' would be out of place (certainly no more so than calling it a 'pupitre'!)— though of course, if you know for sure what actual form it takes, it might be best to say so; that well-known contrast between FR and EN, where one often emphasizes the function whereas the other emphasizes the form.

I suspect the name given to it here 'pupitre' (my suggestion 'console') is more about the function it fulfils, rather than the literal, physical form it takes; this is almost certainly going to include some kind of computer screen that in some way 'mimics' the setup being controlled.