Google images now has the date option

I tested this for a while but it never worked. I was amazed to see that they finally released this now. To filter images for date it is a matter of adding

&tbs=qdr:m (for a month)
&tbs=qdr:w (for a week)
&tbs=qdr:d (for a day)

to the URL. The structure seems to be the same one as for the normal search results.