NHS gold-plated plastic rest spectacles, 1948-1960.
© Science Museum / Science & Society Picture Library
Manufactured by Algha. Spectacles have been in use in the West for at least 700 years. The earliest had convex lenses, and were designed to be worn by people with long sight to help them focus on nearby objects. Later, concave spectacle lenses were made for peole with short sight. In 1784 Benjamin Franklin (1706-1790) invented 'bifocals' - spectacles split into two parts, each with a different focal length. When the National Health Service was established in 1948, eye tests and spectacle frames and lenses were all provided free of charge. Unfortunately, demand greatly exceeded supply, and it became necesary to produce a large stock of a limited range of frames to meet this demand which had created waiting lists of up to two years for glases.