Comparing it to giving away the secrets of a magic trick, the company's owner can't say what exactly they provided, but allowed that it's a spin-off of what they normally do:
The company, set up 20 years ago, is expert in building eye-testing equipment for opticians and anti-reflective coatings and tints.
"It's a great honour for a small company, here in Winchcombe, to be able to say we had a hand in it and supply the likes of Warner Brothers."
Ten years ago, the firm created true-colour holographs and sold the technology to US computer giant IBM.
The company previously supplied products for the makers of Wallace and Gromit.