Display technologies for portable communication devices

Kimmel, Jyrki; Hautanen, J.; Levola, T.

doi:10.1109/jproc.2002.1002528

Cited by 28 publications

(12 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…15 These approaches still satisfied the users of the second-generation mobile services, as even the games were very simple, and short message service (SMS) was the main feature of advanced communications in the phones. 9,10 As the first color-screen phones appeared on the market by the end of the 1990s, also wide spectrum light sources such as white LEDs and miniature cold-cathode fluorescent lamps (CCFLs) were used in more advanced products. 9,10 The light-guide design also required better uniformity and spectrally independent output characteristics.…”

Section: State Of the Art Of Backlight Light Guidesmentioning

confidence: 99%

“…9,10 As the first color-screen phones appeared on the market by the end of the 1990s, also wide spectrum light sources such as white LEDs and miniature cold-cathode fluorescent lamps (CCFLs) were used in more advanced products. 9,10 The light-guide design also required better uniformity and spectrally independent output characteristics. Light guides quickly started to apply more advanced features such as statistically distributed scattering centers, reflecting and refracting output coupling designs, 15 and, finally, microreflector and refractor arrays.…”

Section: State Of the Art Of Backlight Light Guidesmentioning

confidence: 99%

“…An important category of mobile displays is the organic light-emitting diode (OLED) display. 9,10 In these displays, the light emitted by the display is generated directly at each subpixel, and grating arrays will not be required in these displays either. The power consumption of OLEDs is highly dependent on the content to be displayed, as the electric power is transduced to emitted light for the most part only at the lit subpixels.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Diffractive backlight grating array for mobile displays

Kimmel¹,

Levola²,

Laakkonen³

2008

J Soc Info Display

View full text Add to dashboard Cite

Abstract— The display backlight unit (BLU) is the most power‐consuming subunit in mobile liquid‐crystal displays. The state‐of‐the‐art BLUs utilize scattering, refractive, and reflective microstructures to generate a uniform distribution of white light through the display. More effective means of transmitting light through the display color filters could be obtained by using diffraction, but previously proposed diffractive backlights do not fully utilize all the possibilities to design gratings effectively for optimal color separation and outcoupling. This paper presents a new pixelated diffractive backlight grating array as an approach for overcoming these obstacles in BLU design. A model array was fabricated to couple out red, green, and blue primary colors from the respective subpixel locations. The results show that it is possible to manufacture such an array and that the light couples out as intended, giving a starting point to design mobile‐display modules with low light‐transmission losses.

show abstract

Section: State Of the Art Of Backlight Light Guidesmentioning

confidence: 99%

Section: State Of the Art Of Backlight Light Guidesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Diffractive backlight grating array for mobile displays

Kimmel¹,

Levola²,

Laakkonen³

2008

J Soc Info Display

View full text Add to dashboard Cite

show abstract

“…Characterized by the screen diagonal size loosely less than 30 mm, microdisplays are used to resolve the contradiction between the large viewing size and small device size [1]. They are applied in two main fields, projectors [2,3] and near-to-eye (NTE) systems [4,5].…”

Section: Introductionmentioning

confidence: 99%

Optimal scan strategy for mega-pixel and kilo-gray-level OLED-on-silicon microdisplay

et al. 2012

View full text Add to dashboard Cite

The digital pixel driving scheme makes the organic light-emitting diode (OLED) microdisplays more immune to the pixel luminance variations and simplifies the circuit architecture and design flow compared to the analog pixel driving scheme. Additionally, it is easily applied in full digital systems. However, the data bottleneck becomes a notable problem as the number of pixels and gray levels grow dramatically. This paper will discuss the digital driving ability to achieve kilogray-levels for megapixel displays. The optimal scan strategy is proposed for creating ultra high gray levels and increasing light efficiency and contrast ratio. Two correction schemes are discussed to improve the gray level linearity. A 1280×1024×3 OLED-on-silicon microdisplay, with 4096 gray levels, is designed based on the optimal scan strategy. The circuit driver is integrated in the silicon backplane chip in the 0.35 μm 3.3 V-6 V dual voltage one polysilicon layer, four metal layers (1P4M) complementary metal-oxide semiconductor (CMOS) process with custom top metal. The design aspects of the optimal scan controller are also discussed. The test results show the gray level linearity of the correction schemes for the optimal scan strategy is acceptable by the human eye.

show abstract

“…Active-matrix LCDs (AMLCDs) have been favored for use in mobile applications due to their high image quality and long-term reliability. 1 However, the growth of mobile multimedia systems demands further performance enhancement of LCD panels, such as higher dynamic image performances. However, motion blur is still one remaining disadvantage of AMLCDs.…”

Section: Introductionmentioning

confidence: 99%

Motion‐blur characterization with simulation method for mobile LCDs

Zhang¹,

Li²,

Yang³

et al. 2008

J Soc Info Display

View full text Add to dashboard Cite

Abstract— A simulation method based on measured liquid‐crystal responses and human‐vision properties was proposed to characterize the motion blur of LCDs. A perceptual experiment was implemented to validate the simulation model within different viewing conditions by changing the visual angle. The results indicate that the smaller visual angle of the mobile display has no statistic significant effect on smooth‐pursuit eye tracking when perceiving a moving block on a screen. The calculation process of quantitative metric was presented based on the measured light behavior and the simulation model. In the end, the different motion‐blur reduction approaches were evaluated for mobile LCDs.

show abstract

Display technologies for portable communication devices

Cited by 28 publications

References 18 publications

Diffractive backlight grating array for mobile displays

Diffractive backlight grating array for mobile displays

Optimal scan strategy for mega-pixel and kilo-gray-level OLED-on-silicon microdisplay

Motion‐blur characterization with simulation method for mobile LCDs

Contact Info

Product

Resources

About