Many variables involved in that question. What kind of lights? Each type of light has a certain amount of UVB output at certain distances. The closer the distance the greater amount of UVB. Many companies that manufacture their lights are not willing to give you that information, possibly because they have never had the research done on them or do not want the information out for comparison. If it is low output, it is probably safe, but do the research on the type of light. I forgot the website, but there is a company that sell mercury vapor lights that has a lot of good statistical data on different UVB lights and the amounts of natural exposure that one could expect in certain parts of the world. Not Mega Ray, but Mega(something?). If the lights that you are using are something like a mercury vapor, you will probably fry your little leopards.
Cheers,
Michael