After leaving school, he entered his father's optometry business, while learning the theoretical side from Oliver Lodge.

[1] When Thomas was twenty-one, his father went on a long voyage to recuperate from overwork but died during the journey.

Thomas took over and not only maintained the reputation of the lenses his father had designed but he continually improved them and added new patterns.

He also invented the Naturalist's Camera for which he received the medal of the Royal Photographic Society.

Bergheim, who wished for a lens which would give him correct drawing and soft definition without sacrificing the natural structure of the original.