Knowledge about el Character LCD Modules

The polarity of the voltage waveform of the EL luminous efficiency and life has a very important influence in the inorganic electroluminescent ZnS the conductive thermal electrons are accelerated by the high electric field excitation collision trespassing excitation light effects are produced, using unipolar pulse voltage as a driving voltage, will affect the service life, and the use of positive and negative polarity pulse voltage as the drive voltage in favor trespassing recovery after touch, do not affect life.graphic lcd display module
EL lead electrode is formed by two insulating layer between the electrodes to isolate the performance of the capacitive load driving circuit, the equivalent load of approximately 0.2-0.9nf/cm2 EL driving current is small, the size of the area of ​​the main light emitting material with requirements of the brightness ratio and to determine, generally 0.14mA ~ 1mA/cm2, EL larger the area, the capacitive load is quite increases, also increases the current flow, and thus the driving circuit with the capacitive load capacity and also considerably improved impact resistance.
EL brightness is closely related with the characteristics of drive power, to maintain the brightness is not lit, to changing the polarity of the pulse voltage, which is driven by AC EL, between the poles of a voltage when the EL, the light emitting layer is established field. Electrons in the electric field direction under the effect of accelerated motion reverse, when the electric field strength is strong enough, enough number of electrons motion, fast enough, through the collision, the luminescent material atoms in the excited state occurs on the level jumping, excited state electron light level performance jump move, if the electric field direction of the same, the number of electrons in motion gradually reduced, to excite atomic level transition occurs, the brightness of the EL gradually decreases until it does not light, if the electric field is alternating, the direction of the electron with the electric field is always in high-speed motion changes state, the atom level transition occurs uninterrupted, when the electric field changes its height when the frequency is fast enough will remain stable, no flicker, practical applications, can be roughly considered at a certain frequency is proportional to the luminance and the driving voltage, typically drives the EL peak value of the AC voltage 30V-250V
Brightness not only affected by the voltage and frequency dependent, can also be refined slightly landlord for a certain brightness is proportional to frequency voltage, operating frequency is usually cold 50-400Hz sometimes several KHZ frequency, which can be accessed at this time brightness saturation voltage plus large, no obvious improvement in the luminance. Moisture and brightness, life is inversely proportional.OLEDs
EL from the half-life is (half brightness) to be measured. It is defined as the display brightness down to half the period of initial luminance, usually this time is 3000-12000Ph, visible EL life is very long, but long high-pressure, high-frequency, so that the brightness is saturated for a long time, it will accelerate the aging and shorten its life. Because the human eye into a nonlinear response to luminance of semi-bright and full bright differentiate obvious, thus allowing EL light work less than full, and in the circuit with self-complementary circuit voltage through a corresponding increase to prolong life, but This formula in the production process can be improved to extend its life.