Paul J. Kane

System considerations for RGBW OLED displays

Abstract— The fabrication of full-color RGBW OLED displays using a white emitter with RGB color filters has been previously described. This paper discusses the effect of several display-system factors on the important RGBW OLED display performance attributes of power consumption, lifetime, and perceived image quality. These display-system factors include the spectrum of the white OLED, the white OLED structure, the color-filter selection, the subpixel aperture ratios, and the pixel arrangement (including sub-sampling).

4.3: Lifetime- and Power-Enhanced RGBW Displays Based on White OLEDs

In this paper, we describe techniques for improving the power consumption and lifetime of full-color AMOLED displays with an RGBW pixel format. A highly efficient and stable white OLED, with color optimized for the display white point (D65) has been developed, which enables low power consumption as well as stable emission. Additionally, a novel approach for improving the lifetime of RGBW displays using subsampled R and B subpixels is discussed.

Full-color AMOLED with RGBW pixel pattern

Abstract— A full-color AMOLED display with an RGBW color filter pattern has been fabricated. Displays with this format require about one-half the power of analogous RGB displays. RGBW and RGB 2.16-in.-diagonal displays with average power consumptions of 180 and 340 mW, respectively, were characterized for a set of standard digital still camera images at a luminance of 100 cd/m2. In both cases, a white-emitting AMOLED was used as the light source, and standard LCD filters were used to provide the R, G, and B emission. The color gamuts of these displays were identical and the higher overall efficiency of the RGBW format results from two factors. First, a large fraction of a typical image is near neutral in color and can be reproduced using the white sub-pixel. Second, the white sub-pixel in an RGBW AMOLED display is highly efficient because of the absence of any color filter. The efficiency of these displays can be further enhanced by choosing a white emitter optimized to the target display white point (in this case D65). A two-emission layer configuration based upon separate yellow and blue-emitting regions is shown to be well suited for both the RGBW and RGB formats.

P-34: Image Quality Impact of Pixel Patterns and Image Processing Algorithms for RGBW OLED Displays

Several RGBW pixel patterns were simulated with different RGB to RGBW color conversion approaches, and the resulting image quality was quantifiably compared to RGB pixel patterns. The image quality of select RGBW pixel patterns was found to be comparable or slightly higher than traditional RGB pixel patterns having the same number of pixels.

Interlaboratory comparison of photographic modulation transfer function measurements

The precision of sine-wave modulation transfer function (MTF) measurements of a color negative film was investigated at three laboratories within the Eastman Kodak Company. A spatial frequency range of 0.19 to 40.0 cycles/mm on Kodacolor Gold 100 film was em- ployed for the measurements. The precision of the measurements at two of the laboratories was found to be equal, with the third set of measure- ments being less precise. The precision was measured by the standard deviation, at discrete frequencies, of replicate MTF measurements. This work may provide necessary supporting experimentation for an ANSI/ ISO color-negative-film MTF standard, which would enable meaningful comparisons of results between laboratories.

Hybrid light coding for fast and high-accuracy shape acquisition

We present a high-accuracy shape acquisition approach that uses a combined Gray code and phase-shifting structured light projection. The Gray code pattern coarsely divides the projected plane into local regions, whereas phase-shifting precisely determines the pixel-accurate index for each point on the plane. The combination of the two codifications greatly decreases the number of patterns as compared to Gray code alone. It also retains high resolution without the required phase unwrapping step in the phase-shifting algorithm, which is time consuming. Most importantly, it works for multiple objects or discontinuous surfaces without using markers, as employed by the phase-shifting method. Experimental results with real objects and human faces indicate the effectiveness of the proposed approach.