TDK has started mass production of a see-through OLED display for phones.
"The product is a see-through type, but is constructed so that the display contents cannot easily be seen from behind, to protect the user's privacy", said TDK.
It is a QVGA (320x240) 2.4in (36x48mm) display, with transmittance of 40% and 150cd/m2 brightness.
Rather than using separate red, green and blue emitters, there is a white-emitting material behind a grid of RGB colour filters.
"The use of the colour filter principle means that the service life of the each colour of RGB elements is identical, and colour shift is absent," claimed TDK.
The firm refers to its technology as 'organic electroluminescent' or 'organic EL', even though it is based on Kodak's small molecule OLED intellectual property, and fast switching characteristics allow passive matrix control.
"All organic EL displays from TDK employ the passive matrix principle," said the firm.
Called UEL476, it will be available this spring.