Ocean 2015 – FPD rendering
Modelling a smartphone display from measurements
Flat panel displays (FPDs) have complex light emission properties. The perceived luminance of a pixel highly varies with direction. This dependency to the viewing angle is not the same for all sub-pixels, and changes with color levels, sometimes resulting in very poor image quality when viewed from a side.
Ideally, rendering a FPD display for assessing image quality would require:
- 180° hemispherical mappings of surface emission
- For each sub-pixel type
- For multiple sub-pixel levels between 0 and 255
- As spectral values, or as non gamma-clipped colorimetric coordinates, such as XYZ
This data was provided by ELDIM, which manufactures quality measurement systems for FPDs. The measured surface emission mappings range over 176°, or 88° to the surface normal direction, and were repeated for red, green and blue sub-pixels, for 9 sub-pixel levels each. The data is provided as CIE XYZ or spectral (31 wavelengths) values. The hemispherical distribution is represented as a circular image, similar to a fish-eye projection.
The information is then used in Ocean as surface emission properties, together with any regular image to be displayed on the simulated device.
Application : visualizing display quality and redability
By rendering a smartphone from various angles of view, we can assess one of the keys figures of merit for a FPD:
Rendering in various environments allows evaluating readability when lighting conditions change:
By changing the reflective properties of the glass surface, we can evaluate the impact of anti-reflective coatings on contrast:
The new features in Ocean 2015
The following new features from Ocean 2015 were used here, and may have many other applications:
ELDIM display measurement systems
ELDIM is a partner company located in Normandy, France. It provides fast and accurate systems for measuring the angular characteristics of displays, in terms of luminance, color coordinates, spectral and polarization content.
Stay connected : next week feature highlight
Next newsletter will be focused on measured BRDFs, one of the most requested feature of the new release!
Other Ocean 2015 features
New features will be presented this fall in a weekly “feature higlight” update. In the meantime, you may discover them by downloading Ocean 2015