Edwin H. Land, whose research into optics led to the development of the first commercially successful instant camera, announced yesterday that he would end his active involvement with the company spawned by that invention, Polaroid Corp., to devote full time to pure research.

Land resigned as chairman and director of Polaroid yesterday. He has been gradually relinquishing control of the company he founded nearly a half century ago to devote more attention to the Rowland Institute for Science, a not-for-profit research company he set up in 1979 and funded with Land family money. The Land family owns about 10 percent of Polaroid.

The 73-year-old Land long has been an oddity in American business ranks. Even as the operation of Polaroid dominated his responsibilities, Land continued to do research for the company, generally preferring that to management.

Land will continue as Polaroid's honorary chairman, a spokesman said, and serve as a consultant for the remainder of this year. William J. McCune Jr., Polaroid's president, assumed the title of chairman.

"I have been planning for some years to change from my career at Polaroid to a new one in pure scientific research," Land, who rarely gives interviews, said in a statement. "The research I have already been involved in at the institute seems so significant that I regard it as important not to delay further my move to this new organization."

There was no elaboration on the type of research Land mentioned, although the statement said the Rowland Institute, which has a staff of about 20 scientists, is working in fields ranging from physical chemistry to human color vision.