@navneetjain - First, it really depends on what country you’re in. In the USA, you can sell off a mirror that you’ve made for yourself, but you can’t turn it into a business selling the mirrors. The reasons involve the patent on the method of displaying information through a sheet of one way glass. Mich looked into it a few years ago and decided that the licensing the patent from the company that owns it wasn’t worth it.
Of course, the above advice is highly depended upon how your company enforces patent infringement. I am not a lawyer and would recommend seeking a good one before starting a business selling the mirrors.