Displays and OLEDs

Introduction

Film Optics has extensive experience in designing and manufacturing specialist film structures for use in display applications. Our core expertise is in the design and development of complex and challenging structures for use in specialist applications and new product development.

Displays

Whilst specific details are confidential, areas in which we have developed and manufactured optical structures for clients include...

  • Interactive display solutions
  • Micro-screen and near eye applications
  • Tactile screens using opto-mechanical actuation
  • Security screens with very narrow viewing angles
  • Auto-stereoscopic 3D displays
  • Dual view screen
  • Micro Fresnel backlight films
  • Front lighting solutions
  • Controlled viewing angle solutions

OLED out-coupling films

A large proportion of the light produced by OLED’s is trapped as ‘waveguided modes’ inside the OLED due to the effects of total internal reflection, particularly at the substrate/air interface. Film Optics developed a surface structured out-coupling film using an array of micro-lenses which enables these waveguided rays to be emitted by changing the incident angle as shown in the figure. The result is a gain of 30% - 70% in the total light emitted by the OLED.

  OLED out-coupling films

As each OLED device has its own unique emission profile, to maximise the out-coupling efficiency it is important to use a structure designed to work with the precise characteristics of the OLED. Film Optics has extensive expertise in the design, modelling and testing of novel structures gained working in conjunction with leading OLED developers.
Independent testing of structures designed and manufactured by Film Optics has confirmed that our structures out-performed those of structures available from other sources.

Integrating Out-Coupling and Light Management
The integration of a micro-structured optical film on the surface of the OLED enables more options than simply improving the efficiency of the device. By modifying the surface micro-structures , the direction and intensity of the light emitted by the OLED can be manipulated to create a variety of effects.

The out-coupling optical features can be modified to provide additional light redirection (at a slight loss to the out-coupling efficiency), so that the same film can for example make the OLED comply with anti-glare standards for office fittings, provide an asymmetric ‘wall washer’ light pattern, or give a ‘bat wing’ two beam strip emission useful in retail. In this way a single OLED design, coupled with different surface films, produces a range of lighting products.