Art-house cinema chain Picturehouse, which owns Norwich's Cinema City is being acquired by multiplex chain Cineworld in a �47.3mn deal expected to net its founder a multimillion-pound payout.

Picturehouse owns 21 cinemas with a total of 80 screens, including the Abbeygate Picturehouse in Bury St Edmunds, and the Arts Picturehouse in Cambridge.

Cineworld, which is also buying Picturehouse's theatrical distribution arm, Picturehouse Entertainment, said the deal would allow it to tap into 'new audiences in a high value and growing part of the market'.

Picturehouse, which has 750 staff, would continue to be run as a separate business within Cineworld and its existing management team would remain in place, Cineworld added.

Other cinemas owned by Picturehouse include the Cameo in Edinburgh, the Picturehouse in Stratford, east London, and the Phoenix in Oxford – the chain's founding cinema, bought in 1989.

Lyn Goleby, co-founder and managing director of Picturehouse, is set to pick up a substantial sum from the deal, as as one of the company's major shareholders. The Arts Alliance and investment firm Albion Venture Capital also held significant stakes in Picturehouse.

The art-house chain was founded to challenge the multiplex cinema model and show independent, art-house and foreign language films that often do not make it on to the big screen.

Ms Goleby said it would stay true to its roots after the takeover. 'We are known for our high quality city centre cinemas and our distinctive, wide-ranging programming,' she said.

'The unique character of Picturehouse cinemas will remain and our team will continue to bring the widest range of film to customers.'

The deal was announced on the opening day for Picturehouse's 21st cinema, The Duke's at Komedia in Brighton, and it hopes the Cineworld acquisition will allow it to launch another 10 sites that are in the pipeline.

Ms Goleby and co-founder Tony Jones started the group when it bought the Phoenix in Oxford and has since expanded through acquiring and building cinemas, particularly in London and university cities such as Cambridge, Edinburgh, Brighton and York.

Mr Jones, who held a minority stake in the group, is now retiring, but will remain involved with the Cambridge Film Festival, which is screened at the Arts Picturehouse in Cambridge.

Cineworld is launching a cash-call to investors to raise around �16m to help fund the Picturehouse takeover and said Ms Goleby will put �1m into the share placing.