During the one and only sleep-over I ever had as a child, I was introduced to the Viewmaster showbeam!
I already had a Viewmaster – these great binocular-like things you could put a cartridge into and by facing a light source it would look like you could see the images in the binoculars. It was almost like looking into another dimension! They were ace!
Well the Showbeams, did what the other Viewmaster toys did, but they took the slide-like cartridges and projected them onto the wall! Basically the show beam was like a torch that you would slip the slides, or cartridges, into and then you could see the slide show happening in front of your eyes!
Basically it was like a projector. The boy at the sleep-over has a transformers based cartridge and a Scooby doo one too. It was great! When the lights were off it was almost like being at the cinema (A very bad, static framed cinema, mind!)
So, yes, this was a “stereoscopic” toy, and was released in 1982 as part of the Viewmaster range – as well as the binoculars/ classic viewmaster, you could also get a talking viewmaster that would run a narrative at the same time as showing the pictures!
I have a projector now, and it reminds me of that everytime I turn it on. A great toy, I just wish I’d had had one, still I've a projector now. So In your face 1980's!