The need for large print

Many older people have difficulty in reading standard text even with appropriate spectacles and optimum illumination. The situation is made worse by the use of small characters with fine strokes, printed on a patterned background. Also many people who can read standard text find it very tiring, so prefer to read large print when they can.

Large print publications should be designed to specifically help with reading problems, and should not just be an enlarged version of the ordinary print.

With more people living to an older age there is a growing need for publications of all types to be produced in large print. These include:

• Instruction and guide books
• Application forms
• Statements and bills
• Timetables
• Medical information
• Letters from utility, finance and insurance companies

The effects of ageing on eyesight

The problems

The ageing process significantly affects the human eye. Less light reaches the retina, and a decrease in the ability of the eye to change its focus produces an unclear image on the retina. Also eye conditions such as macular degeneration and cataracts are age-related so these conditions are becoming more common.

Macular degeneration

Macular degeneration is the main cause of low vision in the UK. The macula is at the centre of the retina and is used for detailed activities such as reading and detecting colours. People with macular degeneration have to use the less sensitive areas of the retina for recognising characters. This has significant implications on the design of a font for large print publications.

Printed text in 'Times' at 10 point size, as seen by a person with macular degeneration.

Printed text in 'LPfont' at 16 point size, as seen by a person with macular degeneration.

Cataracts

A cataract is an opacity of the lens of the eye. This can occur in different ways so that the light rays which reach the retina may be split causing multiple images. Cataracts can form at any age but most often develop as people get older. Having cataracts is like driving a car with a dirty windscreen -if the sun is in front of you, then your view can be seriously impaired.

Scientific research

The research involved a review of the relevant literature, interviewing publishers of large print materials and others involved in delivering large print materials to the readers. Then a series of practical experiments were undertaken with existing and potential adult readers of publications in large print. The design project independently examined parameters including:

LPfont was designed to maximise character definition and legibility. A full report of the research involved in the development of LPfont is available at www.snapi.org.uk/info/reports/lpfont report/index.htm