There are full spectrum light bulbs and then there are the light box therapy lights. I paid about $100 for my light box. They are different I think.

I don't remember all the facts now, but I think there was a difference between the blue light and the white light. Also check the power of the lamp (LUX or whatever it's called) because it makes a difference in how long you have to use it each day. Mine is 10,000 LUX so I only use it 10 minutes in the morning and will build up to 20min as it gets further into winter.