Timing (as seems to be true with many things, wives tell us) makes a big difference.
You can make it better -- or worse. Timing matters.
CET has much info on this, and several online tool for figuring out when to use (and when to avoid) bright light:
http://www.cet.org/en/index.html (the "self-assessment" link)
It's a big area of research; this is a survey article.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1964886/?tool=pubmed
In the 1980s people thought "bright" --like daylight, with UV --was needed; researchers eliminated UV--it still worked;
they eliminated "warm" multiple phosphor lights--it still worked. Plain cool white office fluorescent tubes were used through the 1990s for depression.
Then in 2001 a new visual receptor in the eye was discovered
http://scholar.google.com/scholar?q=2001+melatonin+receptor
The old "bright lights" worked because they were bright in the narrow effective range: 440–480 nm (strongly emitted in both fluorescent and "white" LED lights).
http://www.jstage.jst.go.jp/article/jpa2/28/5/28_217/_article
Light is strong stuff, turns out. People most affected are very young children, older people, and some new mothers.
Yellow light from ordinary compact fluorescent 'bug light' bulbs works fine at night to avoid disrupting sleep by the way; it's plenty to read with or get around in a room say to feed a baby or take care of an old person without causing sleep problems.
If you're not in those categories -- younger adults have really robust sleep cycless -- this may be hard to believe 'til you read the science.
Spectra typical of lights with the strong blue emission: Regular fluorescent:
http://ledmuseum.candlepower.us/twenty1/palmt-10.gif
White LED:
http://ledmuseum.candlepower.us/tenth/mag3aa1.gif
CFL 'bug light' -- yellow filter on the tube, blocking almost all the blue:
http://ledmuseum.candlepower.us/seventh/cflbl1.gif
If you're reading this and want more on winter depression that first link above is the best place to start.