Who invented the Blu-ray player?

It was originally invented by Sony.

This has become a very contested notion since the emergence of a technology trail going back some 25 years in the Silicon Valley. Patent Office research indicates the submission of a methods and apparatus patent application being issued to Kenneth W. Easterling of San Jose, California. This application clearly defines the novel and unpatented domain of Ultraviolet light sources as applied to laser diodes used in optical storage devices.

Historically, these light sources were of an Infra-red nature which meant they were to be found on the lowest end of the light spectrum and at a lower frequency. Subsequently, when applied to precision focusing limited the device to a relatively large "footprint". To take advantage of the precision tuning capability of the ultraviolet frequency or the highest end of the light spectrum, and allow the device to have the highest resolution, thus "footprint", Mr. Easterling applied for a methods and appartus patent in November of 1992.

In April of 1997, Mr. Easterling approached Sony's Technology Center in Rancho Bernardo, California with a revolutionary leap in technology for the Compact Disc industry. A non-disclosure agreement was signed by Sony's then Vice President of Technology and a transferrance of technology began. Years passed and the interest level ceased.

In 2001 Sony Corporation introduced Blu Ray Disc technology and rest is history.