Research Visa is granted to those desiring to go to India for undertaking some Research work. Usually the Research Scholars applying for Research Visa have their case sponsored by the Shastri Indo-Canadian Institute which is a body jointly set up by India and Canada to promote research. If your research work is sponsored by some other institute or university or yourself, then also the procedure remains the same.
Please note that you have to apply for Research Visa even if you hold a Person of Indian Origin (PIO) card or Overseas Citizens of India (OCI) card issued by the Government of India.