Electroluminescent Panel Research Articles

The role of payoffs and signal ratios in criterion changes during a monitoring task.

Forty-eight subjects detected a long-duration (1.7 or 1.3 sec.) change in brightness (from a 5 ft.-l. standard to a 4 ft.-l. level) of an electroluminescent panel during a 60-min. monitoring session. Signal/nonsignal ratios (1/9 or 1/1) and payoffs (lax, neutral, or strict) were combined factorially in a between-subject design. Signal ratios affected both the percent of signal detections and the percent of false-alarm errors. When subjects monitored under the lower signal ratios, a decrease in percent of signal detections occurred over time. Payoffs affected only the percent of false alarms in the higher signal rate conditions. Signal detection theory analyses resulted in a slight decrease in d' and a marked increase in β during the watch period. The change in β was due primarily to the lower signal ratio conditions. Payoffs had no effect on subsequent β change. It was concluded that signal ratios rather than payoffs play the major role in determining decision performance in simple visual monitoring tasks.

Instant Xrays from electroluminescent panel

Instant Xrays from electroluminescent panel

Convenient Lighting System for Inducing the Production of Sexual Forms of Aphids Feeding on Artificial Diets

A temperature of 15°C and a daily photoperiodic regime of 14 hours of darkness and 10 hours of illumination (10–20 lux) provided by green electroluminescent panel lights (domestic “night-lights” made by the General Electric Co.) induced virginoparae of holocyclic strains of the aphids Mysus persicae (Sulzer) and Aphis fabae Scopoli to produce sexual morphs within 2–3 generations. The aphids were reared on artificial diet.

The Electroluminescent Panel as a Binary Light Source

The most readily available and least expensive device used to expose very small areas on film, as required for experiments in image processing, has been found to be the electroluminescent panel (EP). This device has several characteristics that are highly advantageous for use in replacing a tungsten light source and a shutter. The EP luminance output is a function of both the ac driving voltage and frequency and can be turned on and off very rapidly. The EP is available in different spectral emission ranges, allowing flexibility in its use; also the spectral emission can be shifted by driving the EP for a specific application. The spectral output, with reference to how it is affected by driving voltage and frequency, is discussed and the spectral match between the film and the EP is shown. Photographs are used to show in detail the results of the EP binary light source and how it has been used in image processing.

Optical system for precision spark chamber spectrometer

Criteria, design and the performance of an optical system for a large spark chamber spectrometer capable of measuring momenta in the range of 300–1000 MeV/ c to about ±2% and the portion of sparks and fiducials in space to ± 1 2 mm is described. The system is equiped with a grid of fiducials made of electro-luminescent panels surrounding the spark chambers The spark location in space is obtained by interpolation between the local fiducials. The optical system has been stable during the course of a year and a half and showed no deterioration in the precision of locating sparks over that period.

Use of an Electroluminescent Panel as a Small Spot Light Source for Data Recording

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Electroluminescent Panel as a Modulatable Light Source

The electroluminescent panel can be used as a linear modulatable light source at audio frequencies. (Brightness vs voltage linearity is extremely good for modulation as high as 60%.) Linear operation is accomplished by operating the panels at three times the normal voltage with a carrier frequency of 10 kHz. The rapid aging and resultant light loss which normally accompanies operation under these conditions is eliminated through the use of an efficient heat sink.

The application of electro-luminescence to photic stimulation

A new method of photic stimulation is described which uses two electro-luminescent panels mounted in a pair of goggles. When suitably excited by AC, the panels become uniformly illuminated over the whole surface. Flicker is produced by modulating the exciting AC, and a circuit is given for producing square wave modulation of the panel brightness. The goggles standardize the distance between the source and the eye; they also obviate the need to control the ambient illumination. The method has been found to induce photic driving comparable with that obtained with a stroboscope.

Electroluminescent Panels as Pulsed Fiducial Marks in Spark Chamber Experiment

Electroluminescent Panels as Pulsed Fiducial Marks in Spark Chamber Experiment

Saturation of Electroluminescent Image-Retaining Panels by Laser Beams

Saturation of Electroluminescent Image-Retaining Panels by Laser Beams

Electroluminescent Panels as Bright Area Light Sources

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TANGENT SCREEN STIMULI OF VARIABLE LUMINANCE.

In 1961, after several years of experimentation, I presented a self-illuminated stimulus for tangent screen perimetry¹utilizing a white electroluminescent panel lamp which maintains a constant and standardized level of brightness at all times, under all conditions of room and background illumination. The need for such a stimulus of constant and measured luminance has been recognized for years. It was one of Goldmann's^2,3prime considerations in designing his perimeter and it prompted me⁴to develop fluorescent sulfide tangent screen stimuli activated by ultraviolet (black) light which thus become their own source of light. It has been almost impossible to maintain a constant incandescent illumination on all areas of a 1 or 2 meter tangent screen without resorting to complicated and expensive installations of lights and reflectors. Projection methods for use with tangent screens have not been satisfactory and are also difficult to maintain at a constant level

Electroluminescent panels based on glass

Electroluminescent panels based on glass

Zur Vorsensibilisierung von Manganaktivierten Zinkkadmiumsulfiden durch elektrische Felder und Infrarotstrahlung

The powder phosphor ZnCdS-Mn was used to make a more detailed investigation into memory, which was first described by Destriau in 1958. The effect of a field and infra-red radiation is modified by prior sensitization of the luminophore; this is apparent during further X-ray radiation primarily as a much higher luminescence intensity which later slowly decreases. A comparison of the results of measuring the brightness and charge on an electroluminescence panel permits conclusions to be reached on the actual mechanism. When a field is applied it excites polarization, the field of which does not have a great influence on the effect studied.

Recent trends and future developments in radar displays

The paper starts with a brief recapitulation of the development of radar displays, from the simple form of moving coil plan position indicator (p.p.i.) to the development of the d.c.-coupled fixed-coil displays, capable of allowing for target marking during intertrace periods. An extension of this technique uses secondary high-speed deflection coils to provide alpha-numeric identification of the intertrace position.A description is given of a modern transistorized radar display, capable of performing the dual role of raw marked radar display or synthetic display.Improvements in cathode-ray tubes, and the need for the bright display is discussed. Particular emphasis is given to the bright direct-view storage tube, and the method of operation and performance of displays using these tubes is given.Radar to television scan conversion systems are described in both forms, using either the bombardment induced conductivity tube, or the storage vidicon. Some comments are made upon the possible use of new devices such as electroluminescent panels.

Ultrasonic Research at the Ultrasonic Research Laboratory of the Hungarian Railway Scientific Research Institute

The ultrasonic research supported by the laboratory can be classified into two main parts: nondestructive material testing and active application of sonic and ultrasonic energy. In the field of nondestructive material testing, theoretical and experimental attempts have been made on the correlation of the internal stresses of manufactured parts and of the propagation properties of ultrasonic waves. The investigations made up to present proved that, by measuring ultrasonic velocities with an accuracy of 0.1%, the residual stress distributions in metals can be detected. Now, efforts are made to construct a measuring device suitable not only for laboratory tests but also for technical investigations. Some experimental studies have been made on the problem of appointing the size and shape of imbedded scoria and other inclosures in metals, and interesting correlations were found between the identifiableness of the enclosure and the ultrasonic method applied. Some preliminary experiments were carried out in order to test the effect of ultrasonic irradiation on electroluminescent panels and in slightly ionized gases. Work has begun on the development and application of airborne and hydrodynamic acoustic generators to different technological processes, such as combustion, heat exchange, emulsification, etc. The laboratory cooperates with the I. Gynecological Clinic and has developed several methods and devices for ultrasonic therapy. One of their last works deals with the acting mechanism of the resolving gallstones by ultrasonic irradiations.

Construction and Performance of an ELF Display System

An experimental display system featuring a solid-state display screen has been constructed and evaluated. The system includes a 256-cell-per-square-inch electroluminescent panel, row and column drivers for the panel distribution matrix, and character generation equipment to form target images on the display in accordance with a computer-word input. The brightness pattern on the 4-by-8-inch electroluminescent panel is controlled and stored by a ferroelectric microarray. A matrix of gaseous discharge elements called ionic switches distributes the control signals to the ferroelectric structure. Both conventional and novel techniques were used to fabricate the panel. Less than 2 per cent of the 8192 cells of the completed panel are faulty. Highlight brightness is 2.8 foot-lamberts and contrast is 25:1; both figures are below design objectives due to limits set on panel excitation for this model. Image storage time is more than adequate for the 5 seconds frame time of the system, and the electronic scanning matrix performs as required. The general appearance of target images on the panel is satisfactory although uniformity can be improved by better mechanical design and fabrication process control.

A Review of Panel-Type Display Devices

A review of the activities of various governmental, industrial, and academic institutions is made in the field of panel display devices. These devices are thin sheets which can display luminescent information. Insofar as possible the present state of the art is indicated. The displays are grouped as: evacuated, solid, gas, liquid and mechanical. Among the evacuated types are listed the thin cathode ray tubes and the image intensifier. The solid-type displays employ the electroluminescent panel in conjunction with an xy matrix of electrodes. Recent progress in panels of the above type with memory are included as well as a brief discussion of solid-state image intensifiers. Descriptions of proposed gaseous displays as well as of liquid and mechanical displays are included. A brief discussion of switching circuits is included. Actual as well as possible applications of these devices are listed.

Crossed-grid electroluminescent panel displays with sequential and random access

Several electronic systems have been devised to obtain access to crossed-grid or x-y electroluminescent panels. These panels incorporate a continuous layer of glass-imbedded electroluminescent phosphor overlaid by an impedance-matched non-linear resistive layer. This layer is used to suppress the cross-light effect which results from half voltage excitation on the coordinate lines. Arrays with 16 elements to the linear inch have been prepared. Brightness-voltage data are presentd for panels operating in the frequency range of low audio to 300 kc. Magnetron beam switching tubes are employed as the basic switching and modulating elements for both sequential scanning and random access operation. A fast sequential, single pulse system, capable of element excitation in the low microsecond range is described. Where the panel frame time is not critical, an ac burst system is feasible. The random access system is also described. The principle of this system has been demonstrated in a 100- element panel audio-frequency oscilloscope.

Control of persistance in EL panels

The performance of electroluminescent (EL) display panels which employ photoconductors (PC) as the control element is strongly dependent upon the design of the panel, the processing techniques and the materials used in construction. This discussion will be limited to variable persistence panels and the factors which control the shape of the brightness wave envelope. Through proper design and construction, square wave brightness output is possible. Data are presented on panels with (1) a simple layered structure, (2) a layered structure with an optical barrier between the EL and PC layers, (3) a grid type structure, and finally (4) a grid structure with a transparent ohmic conductor between the EL and PC elements.