RGB Primary Colors Research Articles

High-efficiency anti-stokes Raman blue laser in CO2 enables high-luminance RGB laser-driven white light

Stimulated Raman scattering (SRS) is an efficient nonlinear frequency conversion method, enabling simultaneous generation of red, green, and blue (RGB) lasers. In order to synthesize a white light source for laser display by SRS, a 532 nm laser was used as pump source, and high purity gaseous carbon dioxide (CO2) was used as the Raman active medium. First, by optimizing experimental parameters, with an f = 1.5 m focal lens, in 0.8 atm CO2 pumped at 304 mJ, a first-order anti-Stokes (AS1) 495 nm blue laser was achieved, with an energy of 31.9 mJ, peak power of 10.9 MW and conversion efficiency (CE) of 10.5 %. Then, Then, the second-order Stokes light (S2) at 624 nm, residual pump laser (S0) at 532 nm, and AS1 laser were utilized as RGB primary colors. By the variation of pressure below 1 atmosphere (atm), the laser-driven white light (LDWL) with adjustable correlated color temperature (CCT) below 4700 K were simulated. Finally, LDWL up to 2.6 × 1018cd/m2 of a CCT of 3300 K could be synthesized at an RGB power ratio of PR: PG: PB = 0.447:0.094:0.459, resulting in a white light power CE of 44.4 % and luminous efficacy of 113.7 lm/W. In addition, use of the 574 nm yellow Raman light is expected to realize a four-primary (RGBY) laser display scheme with higher Luminance and broader color gamut. Moreover, the feasibility of using a 515 nm Yb: YAG laser as pump source to widen the range of CCT and improve the brightness of LDWL was discussed.

Equalization of RGB coupling efficiencies of metasurface waveguide coupler by adjusting imaginary part of refractive index

Optical metasurfaces offer high-efficiency and flexible wavefront shaping for near-eye displays, especially in wideband waveguide couplers accommodating RGB primary colors. By leveraging the resonance characteristics of sub-wavelength periodic nanostructures, metasurfaces surpass the limitations of traditional optics that rely on multiple components and mediums. In this study, we propose adjustment of the imaginary parts of the material refractive indices as a new method to achieve balanced first-order diffraction efficiencies among RGB colors over a wide field of view (FOV) in an in-coupling metasurface waveguide coupler. Physical mechanism is investigated deeply and systematically in theory. It is found that nanostructure resonances deflect the wavefront and Poynting vector, significantly enhancing first-order diffraction efficiency, while resonance-enhanced absorption plays a crucial role in balancing the diffraction efficiency of RGB primary colors. First experimental demonstration well confirms the practical feasibility of this method and a uniform first-order diffraction efficiency of approximately 20% is achieved among RGB colors across a FOV as large as ∼30° over a single-piece glass substrate. This research provides insights into the design and mechanisms of metasurface waveguide couplers, advancing our understanding of metasurface-based RGB displays and facilitating further advancements in this field.

Exploring Na Doping in ZnO Thin Films: Electrical and Optical Insights

Strategies to achieve p-type behavior in semiconductor oxides are an important current topic of research. Our study showed that sodium-doped zinc oxide thin films are a plausible approach. The insertion of dopant allowed a transition between n-type p-type electrical behavior in specific temperature ranges around 300 K. Annealing procedures under controlled atmospheres, including Ar, N2, and O2, increased the hole density up to a magnitude of 1016 cm−3, although this also reduced the window temperature. The micro-photoluminescence spectra showed an enhancement of defect-related emissions as the dopant content increased. Notably, yellow-green emissions (around 2.38 eV–520 nm) were the most prominent in the as-grown samples. After annealing, a strong redshift of the defect band was observed (around 1.85 eV–670 nm). Our findings showed that p-type ZnO:Na films exhibited emissions associated with RGB primary colors. In a chromaticity diagram, as-grown samples appeared near the white range, annealed films were close to the warm white area, and O2 annealed films trended within the red range.

Повышение защищенности информации от утечки через побочные электромагнитные излучения

The purpose of the article: development of software-implemented ways to increase the security of information from leakage through spurious electromagnetic radiation of a DVI video system. Research method: search for brightness gradations of RGB primary colors that form similar levels of spurious electromagnetic radiation by enumeration of experimental data obtained from fragments of the reconstructed image. Results: the first part of the article provides a review and analysis of the literature on the features of the functioning of the video interface of the DVI standard. The main characteristics of the TMDS coding algorithm, which can affect the parameters of spurious electromagnetic radiation of the video interface of modern computer technology, are considered. The second part of the article presents an experimental setup for analyzing the relationship between the visual contrast of an image and changes in the intensity of electromagnetic spurious emissions from a DVI video system. On the basis of an experimental comparison of the intensity values of side electromagnetic radiation for different color shades specified by RGB combinations, the possibility of using such pairs of color tone combinations that, on the one hand, are acceptable for the perception of information by the operator, and, on the other hand, have practically indistinguishable levels of side effects, is shown. electromagnetic radiation. The third part of the article (this is for the existing one) presents a method developed by the authors to increase the security of information from leakage through spurious electromagnetic radiation of a DVI video system. The possibility of implementing the proposed method for reducing the information content of spurious electromagnetic radiation of a video system when displaying two-color images is shown.

Tuning the Emission Wavelength of Lead Halide Perovskite NCs via Size and Shape Control.

The advent of lead halide perovskite nanocrystals (NCs), which are easily synthesized, ultralow-cost materials and have an impeccable luminous efficiency, has drastically changed the future perspective of semiconductor quantum dot devices. Although the band gap energy of lead perovskite NCs can be tuned by the halide composition, the instability problem prevails for mixed-halide perovskite NCs, caused by phase segregation due to ion migration when an external electric field or light is applied. To avoid this problem and obtain the stable emission of RGB primary colors, in this study, two synthesis pathways of pure-halide perovskite NCs are proposed. One approach is the modified hot injection method with “centrifugation of a frozen eutectic mixture” to separate small NCs efficiently, and the other is the “low-temperature mixing and heat-up method” for target materials including CsPbI3, CsPbBr3, and CH(NH2)2PbBr3 (FAPbBr3). The emission wavelength of FAPbBr3 is tuned ion-stoichiometrically, unlike Cs perovskites. These various synthesis pathways of pure-halide perovskite NCs enable the efficient production of high-quality perovskite NCs and allow precise tuning of the emission color to the desired wavelength. Although there are still several “gaps” remaining in the available emission wavelength, the new methodology proposed in this study could potentially be employed for manufacturing more stable perovskite NC-based optoelectronic devices.

Optical metasurfaces for waveguide couplers with uniform efficiencies at RGB wavelengths.

Optical metasurfaces hold great potential for near-eye display applications with high optical efficiency, light-weight and compactness. Taking advantage of optical resonances in subwavelength features, metasurfaces can diffract optical beams at RGB primary colors efficiently, forming superimposed virtual images over a real-world scene with merely a single glass substrate in augmented realities (AR) applications. We report for the first time a metasurface with double or triple nano-beams in each period for high angle diffraction with a uniform efficiency at RGB wavelengths. An efficiency as high as 30-40% of the first diffraction order is obtained across field of view, allowing a single piece of AR glass for light in-coupling to deliver image uniformly. The underlying physics is investigated through systematic full-vector numerical simulations. It is found that strong resonances inside the nano-beams with different sizes are the main reason for the deflection of wavefront as well as the Poynting vectors, leading to an efficient coupling of the incident light into the first-order diffraction. The resonances also manipulate the light absorption among the RGB colors for uniform efficiency. This work provides a new understanding of optimal metasurface structure for waveguide couplers using multiple nano-beams.

3D Measurement of Human Chest and Abdomen Surface Based on 3D Fourier Transform and Time Phase Unwrapping.

Monitoring respiratory movements is an effective way to improve radiotherapy treatments of thoracic and abdominal tumors, but the current approach is limited to measuring specific points in the chest and abdomen. In this paper, a dynamic three-dimensional (3D) measurement approach of the human chest and abdomen surface is proposed, which can infer tumor movement more accurately, so the radiotherapy damage to the human body can be reduced. Firstly, color stripe patterns in the RGB color model are projected, then after color correction, the collected stripe image sequences are separated into the three RGB primary color stripe image sequences. Secondly, a fringe projection approach is used to extract the folded phase combined 3D Fourier transform with 3D Gaussian filtering. By the relationship between adjacent fringe images in the time sequence, Gaussian filter parameters with individual characteristics are designed and optimized to improve the accuracy of wrapped phase extraction. In addition, based on the difference between the fractional parts of the folded phase error, one remainder equation can be determined, which is used for time-phase unwrapping. The simulation model and human experiments show that the proposed approach can obtain the 3D image sequences of the chest and abdomen surface in respiratory motion effectively and accurately with strong anti-interference ability.

Controllable synthesis of ultrasmall core-shell hexagonal upconversion nanoparticles towards full-color output

Lanthanide-doped upconversion nanomaterials in particular the ultrasmall (<10 nm) nanoparticles have recently gained substantial attention owing to their bright potential in diverse frontier applications such as multicolor displays and biomedical applications. However, it is still lack of mechanistic researches on crystal growth and a fine-tuning of luminescent properties for the ultrasmall nanoparticles. Herein, we report the controllable synthesis of ultrasmall hexagonal core-shell nanoparticles through controlling the crystal growth kinetics processes. By precise manipulation of the reaction temperature and lanthanide ions doping, the size of utrasmall nanoparticles can be reduced to 2.51 nm still with the hexagonal phase, which is critically important for upconversion. Besides, an epitaxial growth of a NaGdF4 inert-shell layer outside the core nanoparticles leads to a 23.5 times enhancement of the upconversion emission still with the ultrasmall size (6.21 nm). Moreover, the RGB primary color emissions are achieved through properly lanthanide ions doping in these ultrasmall nanoparticles and a set of multicolor output covering the visible spectral range are further obtained by precisely adjusting the mix ratio of the RGB ultrasmall nanoparticles, which shows a great potential in full-color displays and anti-counterfeiting applications.

PENERAPAN KEMOMETRIK PADA METODE CITRA DIGITAL UNTUK ANALISIS ION MERKURI (II) DENGAN INDIKATOR NANOPARTIKEL PERAK

Digital image method in quantitative analysis usually uses one of the RGB primary color components (Red, Green, Blue), so that not all digital image data can be extracted. Then needed a method that can render the whole RGB values as variables in quantitative analysis are known as chemometric. This research aims to know the influence of the application of chemometric against the sensitivity of the digital image. Chemometry method used is the Principal Component Regression (PCR) and Partial Least Square (PLS) using Unscramber X software from Camo software, USA.. This method is applied for the quantitative analysis of Mercury (II) ion with silver nanoparticles (NPP) immobilization on filter paper indicator. The research results showed that chemometric has a good influence against the level of the Limit of Detection (LOD) of the digital image, where the level of LOD with chemometric application of the Principal Component Regression (PCR) is 0.4311 ppb, and Partial Least Square (PLS) is 0.4310 ppb smaller than without the application of chemometric Single Linear Regression (SLR) at 0.837 ppb.

High transmittance and deep RGB primary electrochromic color filter for high light out-coupling electro-optical devices

We report a transmittance controllable electrochromic color filter (TCECF) by incorporating new electrochromic leuco dyes and their optimized composition. Each primary color red (R), green (G), and blue (B) electrochromic filter has an excellent transmittance of more than 84% at 650 nm, 540 nm, 450 nm, and the color coordinates are controllable from white (0.332, 0.347) to deep-red (0.621, 0.344), deep-green (0.327, 0.646), and deep-blue (0.179, 0.085), respectively. Also, each TCECF has good coloration efficiencies of 188.7 cm2 C-1 (R), 189.3 cm2 C-1 (G), and 147.8 cm2 C-1 (B) with high optical density change. A full color producible electrochromic color filter (ECF) is designed and fabricated by integrating primary RGB color filters with a refractive index matching adhesive layer. The fabricated three-stack full color producible ECF enables high transmittance of about 61% for clear white light extraction, and it can produce various colors including RGB. This TCECF technology will be very useful for high light out-coupling electro-optical applications, such as smart lighting, smart window, and display.

Enhanced electrochromic performances of Polythieno[3,2-b]thiophene with multicolor conversion via embedding EDOT segment

A heterocyclic oligomer, thieno[3,2-b]thiophene (TT) end-capped famous 3,4-ethylenedioxythiophene (EDOT) unit and their electrosynthesized polymer P(TT-EDOT-TT) have been facilely achieved. To in-depth understand the effects of structural modification on physico-chemical properties and electrochromic performances of monomers and/or polymers, the absorption spectroscopy, electrochemistry, micromorphology, and spectroelectrochemistry were systematically studied. In contrast to TT and EDOT, TT-EDOT-TT possessed extended π-conjugation and narrowed band gap in molecular level. Through carefully comparison with PTT, it has been found that the electrochromic performances of P(TT-EDOT-TT) film exhibited much higher optical contrast (69%, while 3% for PTT in the near-infrared region) and superior coloring efficiency (255.3 cm2 C−1, while 36.8 cm2 C−1 for PTT), and switching times (within 1 s, while more than 9 s for PTT). Notably, P(TT-EDOT-TT) film can achieve the mutual conversion between RGB primary colors (red–green–blue) under variable voltages, which hold quite promising for display applications.

P‐106: Wide‐Color‐Gamut LCD with a Functional Reflective Polarizer

A functional reflective polarizer is added to an LCD's backlight unit to suppress the crosstalk between RGB primary colors. When integrated with a commercial two‐phosphor‐converted white light‐emitting diode (2pc‐WLED), the color gamut of the LCD can be boosted to 133.9% NTSC in CIE 1976, which is comparable to the quantum dot‐enhanced backlight.

RGB Primary Color LED Backlight System Based on MCU

A solution was proposed for the purpose of backlight. According to the principle of three primary color£¬A kind of RGB led backlight was designed with ncp6223 chip dedicated to the RGB illumination or backlight LCD display when ncp5623 was controlled by MCU. The realization of I2C bus which was used to control ncp5623 was taken the measure of direct driving of ncp5623 Using two arbitrary general-purpose IO pin of MCU. In respect of communication protocol, the software simulation was taken. Moreover only minimum system was needed for MCU. This method mentioned above simplified design and cut the cost because of absence of master I2C controller. In respect of software design, every template which realized a function of ncp5623 in the manner of software simulation of I2c protocol was given. In another word, a general method was given. From these templates, a lot of design such as Gradual intensity Dimming, RGB function and so on can be realized. This has a great signification for teaching and practice.

Stimuli-Responsive Color Films of Poly(4-vinylpyridine)-b-Poly(ε-caprolactone) Complexed with Cyano-Capped Chromophores

Here, we develop a method to fabricate stimuli-responsive color films using block copolymer, poly(4-vinylpyridine)-b-poly(ε-caprolactone) (P4VP-PCL), as a template complexed with functionalized chromophores. The P4VP block in the P4VP-PCL can be associated with a cyano end-capped chromophore via charge transfer, which is a noncovalent interaction that can be conveniently manipulated by external stimuli, giving a specific color. The color of the film can be switched by tuning the charge transfer interaction between the chromophore and P4VP with controlled environmental conditions, such as pH, temperature, and moisture, while maintaining high transmittance for visible light due to the formation of the nanostructure of chromophore/P4VP-PCL complex. However, the association/dissociation process between chromophore and P4VP is diffusion-dominated, which may limit the kinetic response time for color change. A way to create quick and reversible color switching can be achieved by a combination of stimuli. The contrasting color change of the responsive chromophore/P4VP-PCL thin films which exhibit RGB primary colors can provide a sensor film that is flexible, fast-responsive, and convenient.

A New Wide-Gamut RGB Primary Set and Efficient Color Encoding Methods for Ultrahigh-Definition Television (UHDTV)

This paper introduces a new wide-gamut RGB primary set and a new color-encoding method that are developed for ultrahigh-definition television (UHDTV). The extended gamut RGB-primary set compared with the conventional CRT-centric gamut is proposed in favor of inclusion of real-world surface colors and in consideration of the current and prospective colorimetric characteristics of flat panel displays using which UHDTV programs will likely be reproduced. The new color encoding method is derived to enable luminance and chrominance information to be accurately separated, resulting in orthogonal video signals. The new luma and color-difference signals generated by the newly derived encoding scheme are demonstrated to have insignificant crosstalk. It is also shown that this fact can contribute to improving image quality after subsampling color-difference components and to increasing compression efficiency.

Scene-Adaptive RGB-to-RGBW Conversion Using Retinex Theory-Based Color Preservation

This paper proposes a retinex theory-based approach to RGB-to-RGBW conversion that preserves the human color perception within a pre-determined level of color distortion for RGBW displays. The proposed method primarily consists of two procedures. In the first, it searches for the maximum intensity level that induces no color distortion for a given image by extracting the white spectra from the common components of the RGB primary colors and adjusting all the pixels' gains uniformly. In the second, the proposed method applies an additional gain to each pixel based on its chromaticness and controls the color distortions arising from the individual gains using the color perception estimated by retinex theory and a feedback mechanism. Experimental results showed that the proposed method was more effective than conventional methods in terms of intensity increment and color preservation. For Kodak test images, the proposed method increased the average intensity by 1.4987 times with a color-distortion level of 0.0094 compared to reference RGB displays, whereas the conventional methods increased the average intensity by 0.8624-1.3429 times with color-distortion levels of 0.0325-0.0682. The surplus intensity yielded by the proposed method can be used to dynamically reduce the power consumption of a liquid crystal display (LCD) backlight or to provide brighter images on LCDs.

Contour Extraction for Images of High Temperature Long Shaft Heavy Forgings

Non-contact measuring method based on CCD camera is desirable for product quality of high temperature long-shaft heavy forgings. In the light of the characteristics of RGB primary color and halation in forging image, the mean red gray value in the high temperature area is proposed as the dynamic threshold to acquire external contours. Internal edges in the image of the hot forging are blurry and discontinuous. For these characteristics, a method based on quadratic B-spline curve is employed to extract and fit the internal contours. Experiments show that this method can effectively remove pseudo features and extract accurate internal and external contours for images of high temperature squaring and chamfering forgings of 900 0C to 1050 0C.

Wide Color Gamut Five Channel Multi-Primary Display for HDTV Application

Wide color gamut displays using monochromatic light sources, such as LED or laser, or applying multi-primary techniques have been introduced by several authors in forms of laboratory based models and for high end natural color vision applications. In order to bring these technologies into the consumer market, one of our latest investigations resulted in a rear projection type high definition multi-primary display (MPD) system which has been realized by a modification of our previous three channel DLP&#x2122; projection television. Thereby the full spectral energy of the UHP&#x2122; type projection lamp is sequentially separated into five primary spectrums through a rotating color wheel instead of the conventional RGB primary colors so that it enables to reproduce a wide range of colors than sRGB compatible display. The main focus of this study is to describe a gamut mapping method that allows using a full range of color gamut of MPD for a given limited color gamut of television signal. This approach is to display an image in such a way that the limited color saturations of the current television signal are adaptively enhanced for every observer. Through the gamut mapping, the picture quality of MPD is significantly improved in comparison with a conventional display system.

光学的ローパスフィルタによるボケの復元機能を有するデモザイキング

We used optical low-pass filters with solid-state imaging devices to produce images. The actual optical low-pass filter was formed by combining two types of doubly refractive crystal devices. The filters cannot sharply cut-off the high frequency components and they reduce the frequency components near the Nyquist frequency. Thus, the projected images on the surface are blurred. This paper presents a demosaicking method that restores the blur caused by optical low-pass filters. Our sharpening approach to demosaicking employs a Landweber-type iterative algorithm. For our sharpening-demosaicking approach, the Bayer's pattern of the RGB primary color filter array is not applicable. Therefore, we studied another color-filter pattern, namely the WRB filter array, which is preferable to the RGB filter array, where W-filtering means that all the visible light passes through it. Our mathematical formulations for sharpening-demosaicking are similar to the least square problem, but there are many different least square solutions. To avoid ambiguity in the spatial frequency domain, we introduced a pass-band limitation that corresponds with the sub-sampling pattern of the mosaicking of color filters into the iterative algorithm.

ディスプレイ Ａｓｉａ Ｄｉｓｐｌａｙ／ＩＤＷ’０１関連 チャネル間相互作用を考慮した液晶ディスプレイの色再現特性のキャリブレーション

We describe a display calibration model that is suitable for liquid-crystal displays (LCDs). In conventional display calibration models, the spectral radiance of light emitted from the display is estimated using the data measured for each primary color based on the assumption of RGB channel additivity, however, this assumption does not hold for LCDs. With only a few measurements of the spectral radiance or tristimulus values, the proposed model accurately approximates the colorimetric characteristics of the display. To evaluate the effectiveness of the model, we used it to measure the RGB primary colors, the CMYK secondary and the tertiary colors. The colors were analyzed based on principal component analysis to identify the effect of channel interaction. The proposed model was found to be more effective than conventional models for the colorimetry of LCDs.