Definitely do not go to HR and create a problem where there isn't one.
Free life advise: I would urge you to train yourself to be respectful in the workplace and focus on looking a woman in the eye.
For some, eye contact is uncomfortable and in that case focus on the area between her eyes ( this worked for me as an awkward young man ).
As a side note, if a woman is uncomfortable with the occasional glances, a minor adjustment to a professional conservative work attire usually can fix this ( in short hide most of the cleavage and don't expose upper thigh ).
If a woman chooses to expose major amounts of cleavage or thigh ( showing thigh ), a certain number of guys are going to glance no matter what.