Yes it's quite big. I use mine as I'm relaxing in an arm chair watching TV. I put the light box on a chair only an arms length away from me and positioned at an angle. You must not close your eyes ...but let the light stream in from this angle, (just off centre) You don't need to look at it direct.
If you problem is early waking (as mine was) have your light session early evening 7.00pm ish.
If your problem is not being able to fall asleep easily then have your light session in the morning.
If you have it longer than arms length away from your face, then you will need to use it for a longer length of time.
Be patient and use it EVERY day at approx the same time.
By Christmas you should be sleeping 2 hrs a night longer than you are now.
Good luck with it Dita. It worked well for me... I hope it does for you.