By Geoff Adams-Spink
Age & disability correspondent, BBC News
The PenFriend is able to store 70 hours of audio
A device that allows blind people to attach and read audio labels on everyday objects has gone on show.
The PenFriend uses minute barcodes which - when scanned by a digital pen - trigger MP3 files recorded on the unit.
It has been developed by a UK firm together with the Royal National Institute of Blind People (RNIB).
It costs less than £60, and can be used to label foods and medication as well as clothing, personal documentation and film and music collections.
"At the moment we are just scratching the surface: we are starting development of address books, organisers, diaries and calendars," explained Alison Long of the RNIB.
The PenFriend is the result of collaboration between the charity and London-based company, Mantra Lingua.
It uses optical identification technology (OID) to print microdots on to adhesive labels which are then read by the scanner in the tip of the PenFriend.
This in turn triggers an MP3 file, usually of the user's own voice, giving a spoken description of the item that is labelled.
It can hold up to 70 hours of audio recordings and can also be used as a standard MP3 player.
This means that people are not limited to just a few seconds to describe the object being labelled.
Information such as a food item's sell-by date, its ingredients and even cooking instructions can be included.
In the case of medication, the purchase date and dosing instructions can be added.
Mantra Lingua originally used a talking pen device with its children's books and approached the RNIB to see whether it would be useful for vision-impaired children.
Coincidentally, the charity had been looking for a low-cost labelling product.
"We saw the potential in the talking pen and commissioned them [Mantra Lingua] to develop and manufacture the PenFriend," explained Ms Long.
She says that the secret of the device is in the software that reads the microdot barcodes.
Audio labelling is not a new idea, but previous versions tended to use more expensive Radio Frequency Identification (RFID) tags to label products.
"This is exciting because it's giving people independence at an affordable price and without being technical," said Ms Long.
"We've already had a lot of positive feedback - so many letters from people who have said it has changed their lives."
It was on show at the RNIB Techshare exhibition in London's Docklands.