Electroholographic display unit for three-dimensional display by use of special-purpose computational chip for holography and reflective LCD panel

Photopolymers have been applied in many Additive Manufacturing (AM) systems and mostly are cured by UV light. Biodegradable photo-curable polymers are very limited and are not commercially available. DLP-projected maskless AM systems become more and more popular nowadays, but its working area is limited if the part resolution is required. For larger working envelope purpose, liquid crystal display (LCD) panel has great potentials, and LCD’s resolution has been improved significantly in the past few years due to the smart phone application. Therefore, in this research, LCD panel is used to replace DLP for a maskless AM system to cure biodegradable materials, Polycarprolactone (PCL) and Poly(ethylene glycol) diacrylate (PEG-DA). Due to the characteristics of LCD panel, the material systems should be sensitive and photo-polymerized in visible-light range, particularly in RGB. In this study, various percentages of visiblelight photoinitiator, Irgacure 784, in the material systems were investigated. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized to characterize cured biomaterials. Because of the use of photoinitiator, the biocompatibility of the cured materials was also concerned, and hence, MTT assay tests were performed. The preliminary tests of fabrication, using the LCD-projected maskless AM system, cured grid patterns to illustrate the feasibility. The visible-light-curable PCL and PEG-DA will be able to be adopted in tissue engineering scaffold applications in the future.

This article documents the results of the first in a series of experiments designed to evaluate the suitability of a novel, high resolution, color, digital, liquid crystal display (LCD) panel for diagnostic quality, gray scale image display. The goal of this experiment was to measure the performance of the display, especially with respect to luminance. The panel evaluated was the IBM T221 22.2" backlit active matrix liquid crystal display (AMLCD) with native resolution of 3840 x 2400 pixels. Taking advantage of the color capabilities of the workstation, we were able to create a 256-entry grayscale calibration look-up table derived from a palette of 1786 nearly gray luminance values. We also constructed a 256-entry grayscale calibration look-up table derived from a palette of 256 true gray values for which the red, green, and blue values were equal. These calibrations will now be used in our evaluation of human contrast-detail perception on this LCD panel.

We present a method to display an integral three-dimensional (3D) image without gaps between multiple display active areas by using multiple liquid crystal display (LCD) panels and multi-image combining optical systems (MICOS). We designed a MICOS to improve the resolution characteristics and decrease the luminance unevenness corresponding to the viewpoint. Furthermore, we developed a method for correcting the distortion of the integral 3D image by using image processing. We prototyped an integral 3D display using four 8K dual-green (8KDG) LCD panels and the improved MICOSs. The prototype display achieved to magnify the display area about 5.66 times more than when a single LCD panel was used.

A digital time‐modulation pixel memory circuit on glass substrate has been designed and verified in a 3‐μm low temperature poly‐silicon (LTPS) technology. The proposed circuit can generate 4‐bit digital codes and the corresponding inversion data by time‐modulation technique to refresh the static image without activating the data driver circuit. Therefore, the data driver of liquid crystal display (LCD) panel is not required to provide the image data of the frame by the proposed circuit while the LCD panel operates in the still mode. The power consumption from data driver can be further reduced in the LCD panel.

A photolithography processing and wet-etching technology for use in forming ZnO transparent electrodes that are just a few micrometers in line-widths for application to Liquid Crystal Display (LCD) panels was developed. The chemicals (developed or obtained commercially) used for the photolithography process included a strong alkaline photoresist-developer, an alkaline photoresist-stripper with pH11-13 and a weak acidic etchant with pH 5.5-6.8 suitable for ZnO compound films with amphoteric properties. Optimization of the process conditions for photolithography and etching played a critical part in the development of the technology. We succeeded in forming transparent fine-patterns of Ga-doped ZnO films with 4 micronmeter line-widths and space-widths using this method. These fine line sizes indicate that our technology has reached a technical level comparable to those used for forming the ITO fine-pattern electrodes currently used for commercially available LCD panels.

In‐cell sensor technology applied in Liquid Crystal Displays (LCDs) panels are investigated to enable adaptive adjustment of screen brightness and color temperature based on ambient light, thereby enhancing the display performance of screens in various environments. By incorporating ambient light sensors (ALS) and color temperature sensors (CTS), which are compatible with the normal manufacturing process of LCD panels, TCL CSOT has achieved a technological upgrade compared to traditional LCDs technology. In‐cell ALS referred to a wide sensing range of 0~10000 lux and high resolution of 1 lux below 50 lux. In‐cell CTS showed an effective range of 3500~9000 K with detection accuracy of 800 K. With these sensors, LCDs panel can adaptively change its brightness and color temperature within different environments, leading to a new feature of TV, monitor and other commercial LCDs.

Color reproductions for LCD (Liquid Crystal Display) panels are different from that of CRT (Cathode Ray Tube) display. Color reproductions for a typical color LCD panel for personal computer (TFT transmissive type for Sharp Mebius MN930-X23) are examined. The reproduction color gamut on the (x,y) chromaticity diagram are measured by varying the input digital levels. The color reproduction area becomes smaller in accordance with the lower input digital level. The correlated color temperatures also vary with the input digital levels. The lower the input digital levels, the higher the correlated color temperatures. The method for making the correlated color temperature constant is shown in this paper. The gamma curves for three primary colors are modified to fix the correlated color temperatures. The compensation of the correlated color temperature has been confirmed on the LCD panel.

Our previous study demonstrated massive emissions of liquid crystal monomers (LCMs) from liquid crystal display (LCD)-associated e-waste dismantling; however, the compositions, priority list, and inventory of LCMs in waste LCD panels remain unknown. Herein, we conducted the first comprehensive identification covering a broader range of LCMs, including 21 biphenyls and analogues (BAs), 28 cyanobiphenyls and analogues (CBAs), and 44 fluorinated biphenyls and analogues (FBAs), in waste television/computer LCD panels. A total of 64 of the 93 target LCMs, including 19 BAs, 6 CBAs, and 39 FBAs, were widely detected in collected waste LCD panels. Approximately 10-18 of the 64 detectable LCMs were identified as the main compositions in various waste LCD panels, which contributed to >90% of the total LCMs. Total concentrations of FBAs in the television/computer LCD panel samples were comparable to those of BAs but much higher than those of CBAs, indicating FBAs and BAs being the commonly used LCM categories. The composition distribution of LCMs varied between television/computer LCDs and among different brands of television/computer LCDs. A preliminary estimate of the globally direct release of LCMs from waste television/computer LCD panels into various environmental compartments was about 1.07-107 kg/year, which will increase considerably in the near future.

Anisotropic conductive films (ACFs) are adhesive films with anisotropic conductivity induced by dispersing conducting particles such as metal coated plastic balls and metal particles into polymer matrices such as thermoplastics and thermosetting resins. ACFs have been widely used for driver IC packaging technologies in FPDs(Flat panel displays) such as LCDs(Liquid crystal displays) for last two decades. So far various packaging technologies such as TCP(Tape carrier package) on LCD panel or PWB(Printed wiring board), COF(Chip on flex) on LCD panel or PWB, and COG(Chip on Glass) using ACFs have been realized to meet the requirement of fine pitch capability and make the flat panel displays smaller, lighter and thinner. In this paper, the history of ACF and driver IC packaging are described. In addition, it is mentioned that how important driver IC packaging is in implementing the miniaturization, high resolution, low cost and high display quality. ACF material design for COF which is advantageous in fine pitch interconnection is described. It is indicated that low temperature curable ACF is very useful in improving productivity of LCD modules and reducing the thermal stress at the interface in large LCD modules. We also indicates that the warpage of LCD panel after COG interconnection induces the light linkage issue in LCD modules. Lowering bonding temperature of ACF is also very important in reducing the warpae issue and avoiding the light linkage issue when COG is applied for driver IC packaging in large LCD modules.

We developed an electroholography unit for a three-dimensional display, which consists of a special-purpose c-omputational chip and a high minute reflective liquid-crystal display panel. We implemented them on one board whose size is approximately 28 cm x 13 cm. The chip can compute a computer-generated hologram whose size is 800 x 600 at nearly real time (0.15 s) for an object consisting of 400 points. After the calculation, the LCD panel displays the computer generated hologram made by the chip, and we can observe a three-dimensional (3D) motion image whose size is approximately 3 cm x 3 cm x 3 cm. The pixel pitch of the display panel is 12 μm, and the resolution is 800 x 600. To obtain a 3D motion image with large viewing zone and image size, we need to parallelize the unit. The unit can be readily scaled up, since the units consisting of the chip and the display are easily set in parallel

Image quality of flat panel displays, especially Liquid Crystal Display (LCD), has been improved for these years. Among those flat panels, an LCD has advantage for space occupancy, electrical consumption and heat dissipation and so on. Furthermore, its brightness is noteworthy for radiological image display. Because of an external light source of an LCD panel, the maximum brightness can be expected to exceed a CRT''s. In this paper, experimental remarks on characteristics of several LCD panels are mentioned. And also possibility of LCD as a display device of PACS workstation is discussed. A portable PACS workstation using a LCD panel based on PC under development is introduced.

Determination of toxic metals in discarded Liquid Crystal Displays (LCDs)

A high‐resolution autostereoscopic three‐dimensional (3D) display is proposed. It comprises two light source arrays (LSAs), a transparent liquid crystal display (LCD) panel, a scattering layer, and a lenticular lens. Light emitted from the LSAs is directed onto the transparent LCD panel, which projects the opening units corresponding to different parallax image pixels into distinct spatial locations, thereby creating new pixels. These new pixels are modulated and reconstructed by the scattering layer, incorporating both the original parallax image pixel information and the information from adjacent pixels post‐differentiation. Consequently, when the new pixels are projected through the lenticular lens to the viewpoint, a high‐resolution 3D image is displayed. The experimental results demonstrate the validity of our proposed autostereoscopic 3D display.

A holographic color display is developed with a reflective liquid-crystal display (LCD) panel and with low-power RGB lasers. A holographic system is also developed for simultaneous recording of 3-D color images with a color CCD.

We focused on the off-state current (Ioff) of oxide semiconductor thin film transistors (TFT) (In–Ga–Zn-oxide TFTs), which is lower than that of amorphous silicon TFTs and successfully made a prototype of a 6.0-in. extended graphics array (XGA) reflective liquid crystal display (RLCD) panel integrally including a data selection demultiplexer and a scan driver and capable of displaying still images at 1/180 fps. When still images are displayed, the frame frequency can be set low. This means that the frequency of rewrites of image data is markedly reduced. This leads to the reduction in the power consumption of an LCD panel. Our panel can solve the problems of electronic paper displays: high drive voltage and difficulty of displaying moving images. Thus, our panel is suitable for electronic paper displays.