Making a Plano-Convex Lens

It was early discovered that glass bends light and can be used to magnify. James Frost, a retired glass instrument maker from University College, London, demonstrates how a small plano-convex (flat on one side, round on the other) could have been made. This uses the 'lamp work' technique, now using a gas burner but previously a candle or lamp. Such a lens was known to the Romans, Arabic scientists and 13th century European scientists such as Roger Bacon.

movie file size: 4MB.

shot on 5th March, 1999. Camera: Chris Morphet.