ok, this is a movie I have been trying to find for about 20 years

It was mad in the late 70’s or early 80’s.

possibly a made for TV movie or and episode of Twilight Zone (or something similar)

All I can remember from it is this:

there is a scientist that creates a machine that (I think) accidentally makes a link to another dimension, he invites his assistand and the assistants girlfriend to see it. To prove it works he turns the machine on and places her compact on the platform, the reflection is of a tree. Somehow they get pulled in one at a time, firs the scientist, a few minutes later the assistant, then a few seconds after him the girl. When she gets there she wanders for a couple of days before finding the assistant, discovering he had been there for a week, then they find the scientist and find he had been there for a year.

This has been driving me nuts for years, if you can help, PLEASE! It was a good movie and id like to see it again!