Experimental Study on Voltage Sag Tolerance of LED Electronic Display

Widely used LED electronic displays have high requirements for power quality. Because of the status quo of LED technology update and the lack of related experimental work, this paper first analyzes the hardware composition of LED electronic display and switching power supply module. In addition, the paper points out that the transient tolerance of LED screens is mainly determined by switching power supply modules. Then, a test platform was built, and a certain type of LED screen was selected to investigate the influence of voltage temporary drop value and duration, phase jump, and initial Angle of temporary drop on the tolerance of LED electronic display. It provides data support for evaluating and managing the effects of voltage sags on LED electronic displays and the design of power supply schemes.

Prevention strategies for refractive errors in users of electronic display screens: a systematic rapid review of the literature

The prevalence of refractive errors has been increasing over time, and its correlation with the increase in time spent in front of electronic media and screens has been studied. However, the literature regarding prevention strategies for this phenomenon is scarce compared to that found for other conditions associated with the use of video terminals such as computer vision syndrome and dry eye syndrome. This review aims to compile the main prevention strategies for refractive errors, specifically myopia, associated with the use of electronic media. For this, a systematic rapid review of the literature in databases and gray literature databases was carried out, finding that the general recommendations focus on increasing outdoor exposure at least 120 minutes a day, maintaining a distance of at least 30 minutes. cm from the device screen, take breaksduring reading sessions and do blinking exercises, among others, as well as clinical measures such as the use of ophthalmic drops with atropine, glasses or multifocal lenses, and orthokeratology.

The main subjective manifestations of computer vision syndrome

Purpose: to analyze the main subjective manifestations of computer vision syndrome (CVS).Materials and methods. We examined 100 patients aged 24–36, whose daily professional activity (at least for 2 years) involved visual-intensive work associated with electronic display systems (at least 4 hours a day) and requiring a sufficiently high responsibility level. All patients had complaints characteristic of asthenopia in CVS, indicating the stages of subcompensation or decompensation (in accordance with the recommendations of the Expert Council for Accommodation and Refraction of All-Russian Public Organization “Association of Ophthalmologists”). Each patient underwent an individual interview which was conducted according to the standard technique in order to identify the range of complaints that arise from long-term work with a computer.Results. The most common ocular (visual) subjective manifestations included the foreign body sensation, “sand” and itching in the eye; dry eyes; tiredness of vision; redness of the eyeballs; tension of eye muscles; “cramps”, burning in the eye — (which was mentioned by 100% of the testees). Other manifestations were somatic (headache — 89%; pain in the neck and the back — 79%), professional (patients wishing to interrupt work or take a break — 83%; periodic loss of visual concentration — 77%) and medico-psychological (the fear of vision deterioration — 65%).Conclusion. The established subjective manifestations improve the prospects of CVS diagnostics and can serve as basis for assessing the quality of life of patients engaged in vision intensive work.

Bluetooth Controlled Notice Board Using Arduino

The project is an electronic notice board that is controlled by an android device and displays message on it. Traditionally, there were notice boards where any information or notice had to be stick daily. This becomes tedious and requires daily maintenance. The project overcomes this problem by introducing an electronic display notice board interfaced to an android device through Bluetooth connectivity. The Bluetooth receives the message from the android device that is sent to an Arduino. Notice board is a primary thing in any institution/organization or public utility places like bus stations, railway stations and parks. But sticking various notices day-to-day is a difficult process. The Notice board is a common display for effective mode of providing information to the people, but this is not easy for updating the messages instantly. This project deals about an advanced Hi-Tech wireless Notice Board. This system is enhanced to display the latest information through an Android application of smart phones or tablet.

Modeling and Recipe Optimization of Anti-Glare Process Using Sandblasting for Electronic Display Glass

Recently, anti-glare (AG) surface treatment technology has been considered as a standard process to enhance the visibility of electronic display devices. For AG, the hydrofluoric acid (HF)-based chemical etch method is the most common approach for the current display glass industry. However, in order to overcome the environmental and durability degradation problems of the HF-based chemical etch method, this paper proposes an eco-friendly physical surface treatment technology using the sandblasting method. Based on the preliminary analysis results using the central composite design (CCD) method-based response surface modeling methodology (RSM), additional experiments and analyses were performed for process modeling and optimal process recipe generation. To characterize the sandblasting process, the mean value of haze was considered as the process output, and the pressure of the nozzle, the distance of the nozzle from the surface of glass, the glass feed rate, and the grit size of the abrasives were considered as process inputs. Based on the process model using the statistical response surface regression method and machine learning-based approaches, the proposed method can generate optimized process recipes for various haze targets of 10%, 20%, and 30%, with an average haze difference of 0.84%, 0.02%, and 0.86%, and maximum deviations of 1.26%, 1.14%, and 1.4%, respectively. Through the successful completion of this work, it is expected that the proposed surface treatment method can be applied to various products including mobile phones, tablet PCs, and windshields of vehicles.