This shirt is made of chemical fiber.

My specialty is fiber optics.

It's difficult to understand the principles of electrooptics.

He is immersed in the study of geometrical optics.

He has expert knowledge.

He is studying computer science at a specialized school.

He couldn't say anything about issues outside of his field of expertise.

There are many different specialty stores in this town.

He is a specialist fool, with no interest in anything outside his field.

She is planning a date with her current boyfriend.