1. R. Bhandari, "Device for and method of making element appear in shortest network path by minimal decrements and increments", Patent #8,233,397, granted July 31, 2012 by United States Patent and Trademark Office (USPTO). 

2. R. Bhandari, "Mode converter and method for generating an optical orbital angular momentum mode of a topological charge of opposite sign", Patent #11,467,342, issued by the United States Patent and Trademark Office (USPTO) on October 11, 2022.