Measuring penetration rates of water vapor and oxygen though OLED packaging materials by mass spectrometry is a new method. Currently, the sampling of penetration gas is dynamic sampling method. The sensitivity of this method is magnitude of 10-4 g/m2day, which can not reach the ideal magnitude of 10-6 g/m2day. Static accumulation sampling method for improving sensitivity of measuring is present in this paper. Comparing with dynamic sampling method, the sensitivity of this sampling method has been improved 1-2 magnitudes. The devices of static accumulation sampling method have been designed. The experiments of measuring penetration rates of water vapor and oxygen through packaging materials have been done. The results and analysis of the experiments have been introduced.
Surface roughness of indium-tin-oxide (ITO) film plays a crucial role on the performance of organic lighting emitting
devices (OLEDs). A set of polishing apparatus with carbon dioxide snow jet as an actuating medium is established, and
the surface polishing of ITO glass are carried out by this equipment. The surface morphology of ITO film is measured by
using an atomic force microscope (AFM) before and after polishing treatment. The results show that before polishing,
the mean values of Ra, Rpv and the RMS of the ITO surface are 1.463, 46.87 and 2.726 nm, respectively. After polishing,
the value decreases to 0.773 nm, 19.51 and 1.078nm. It indicates that the polishing method is effective to reduce the ITO
surface roughness. Another merit of this polishing method is that the polishing process has a cleaning effect to the ITO
glass surface The performance of OLED can be enhanced and the production cost of device can be reduced.
ITO glass cleaning is LCD, OLED and other flat panel display industry's key technologies. At present, the usual wet cleaning technology consumes large amount of water and chemicals, and produces a large amount of contaminant venting. CO2 snow jet spray cleaning has been successfully applied to cleaning the surface of semiconductor chip, vacuum devices and space telescopes. Surface cleaning of indium tin oxide (ITO) film was carried out with carbon dioxide snow jet treatment .Based on the measurements of the contact angles, X-ray photoelectron spectroscopy and scanning electron microscopy (SEM) ,the influence of carbon dioxide snow jet treatment on surface cleaning of indium tin Oxide film was investigated and compared with the samples of low frequency immersion ultrasonic cleaning. Experimental data show that the carbon dioxide snow jet treatment effectively removes particulate and hydrocarbon on ITO surface.
The requirements for ITO glass used in OLED are higher than those for LCD used. It has to keep much strict control on the process for making ITO glass because of the numerous impact factors. An orthogonal analysis method is used to deal with those factors, and the ITO glass good enough for OLED used by the DC magnetron sputtering has been got. The glass properties are 17Ω/, 81% transmittance in visible region. By the orthogonal analysis method, we just use limited materials and take experiment times to finish the crafts research.
Based on modulation transfer function (MTF), a CRT projection tube resolution measurement system has been developed. This system features auto optical focusing and voltage focusing. It has high resolution, fast measuring speed and friendly operation interface. The results indicate that the error of the system is within ±4% by measuring the standard optical slit ranging 30μm to 500μm, while repeatability is better than 95%. Moreover, the measured data demonstrate that the resolution of YAG projection tube can meet the demands of HDTV.
A type of chromatic measuring system, which was based on the spectroradiometric method, controlled by a computer was developed. Spectra, chromaticity coordinates and correlated color temperature (CCT) of light-emitting diode (LED) can be real time measured by this system. It has high resolution of wavelength with 0.2nm, fast measuring speed and friendly operation interface. The measurement data indicate that the system has higher accuracy than CS-100. Difference between measured result and standard data of the system is within ± 2%, while repeatability is better than 98%.
The luminance and the lifetime of new cathode-ray projection tubes, formed by YAG single crystal faceplates deposited with P53 or P53(Ga) phosphor powder, is investigated in this paper. Since the YAG faceplates have high thermal conductivity, the tubes can operate at high power density for long time. The experiments demonstrated that the lifetime of the YAG tubes have reached several thousands hours at high intensity. The cathodoluminescent efficiency of P53(Ga) phosphor is higher than that of P53 phosphor, but the maintenance of P53 phosphor is better.
A 3-inch phosphor screen using YAG single crystal as the substrate has been developed for compact projection displays. In order to obtain higher brightness, high resolution and high resistivity against high-density electron bombardment, the phosphor screen properties are improved from the bulk property of the phosphor as well as the screen process. An improved phosphor which has an optimum phosphor composition of (formula available in paper) has been developed.
It is found that the deterioration of the projection phosphor screen is accelerated by phosphor screen heating. Therefore, a critical step in the development of projection tubes of greater luminosity is the improvement of the phosphor deposition method that relies in a higher thermal conductivity of the phosphor layer. We have developed a novel phosphor deposition technique for YAG projection display application.
We have developed new RGB YAG projection tubes with multilayer interference filters and obtained 60% to 100% higher luminance, higher chromaticity with good resolution, contrast on the projection screens than conventional YAG projection tubes without filters. The details of the filters' design and fabrication are given in the paper.
To overcome the difficulty that the operating pressure range of usual mass-spectrometers does not meet the pressure ranges of gas lasers, the authors have improved the M.S technique by the following four procedures: (1) Making an ultramini-flow valve which can sample the laser mixture and take mass-spectrum only by a little amount of gases; (2) Creating a high pressure ultramini-flow valve possessing pressure-linearity up to 1000 times 133 Pa, especially suitable to M S analysis of TEA carbon-dioxide lasers; (3) Investigating the time-delay and giving an evaluate method to correct them; (4) Proposing a method, the sample gas bottle method, to overcome the sensitivity-fluctuation of the M S tube through comparison.