The hottest way to solve the contradiction between

2022-08-17
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Methods to solve the contradiction between brightness and accompanying heat

the work of xenon lamp light source is divided into three stages: ignition, pre combustion and high-voltage discharge. Its working process is relatively complex, and it is an unsteady gas discharge. In the lighting stage, the discharge first generates an ionization channel near the trigger wire on the inner wall of the quartz tube. The gas is heated due to collision with electrons, and the xenon in the lamp is rapidly ionized, resulting in glow discharge. Pulse transformer T, capacitor C2, thyristor vt2 and resistor R2 form a lighting circuit. When vt2 is turned off and the national finance should increase financial support for scientific and technological research and development of strategic resources related to the fate of the country, voltage U1 charges capacitor C2 through resistor R2 and stores energy on capacitor C2. Generally, U1 is about 1kV, and the charging time is very short. When vt2 is turned on, the capacitor C2 and the inductive resonance discharge of the pulse transformer t generate an igniting voltage of about 5kV at the secondary end of the transformer T. under the action of a strong axial electric field and a high-voltage pulse, the gas is broken down and a discharge channel is formed; In the pre combustion stage, when the input energy is large enough, the electrode is heated to have a certain thermal emission capacity, and the gas in the lamp transits from glow discharge to arc discharge. At this time, the xenon lamp light source can be approximately a resistance, and the voltage U2 is added to both ends of the xenon lamp light source through resistance R1 and diode D to form a pre combustion circuit; In the high-voltage discharge stage, the xenon light source is arc discharge. When VT1 is turned off, voltage U3 charges capacitor C1. When VT1 is turned on, capacitor C1 discharges to the xenon light source, so the xenon light source appears arc stroboscopic phenomenon. In the high-voltage discharge stage, the precombustion circuit always provides the maintenance current to the xenon lamp light source (about 100mA lower production cost)

xenon lamp light source is generally composed of two electrodes sealed in glass or quartz glass, and the shell is filled with xenon and other inert gases. The flash duration of pulse light source refers to the time interval corresponding to 1/3 peak light intensity, which is called pulse width. It is mainly determined by the structure of the light source and the lighting circuit. The pulse width of the existing pulse light source is generally - s, and the instantaneous brightness can reach 1010cd/m2. It is the artificial light source with the highest brightness except laser. The instantaneous light flux of xenon light source can reach 109lm, the flash repetition rate is 1-106 times/min, the working life is more than 106 times, and the luminous efficiency is 40lm/W

in the traditional xenon lamp light source ignition precombustion system, voltage sources are required in the ignition stage and precombustion stage respectively. As shown in Figure 1, U1 is the ignition voltage and U2 is the precombustion voltage, which increases the complexity of power supply design. The new xenon lamp light source ignition pre ignition power supply is controlled by PWM technology. The ignition and pre ignition stages share a power supply. The voltage source is used for ignition and the constant current source is used for pre ignition. In the starting stage, the maximum duty cycle outputs the highest voltage, and the high voltage starting voltage is obtained through series resonance; In the pre combustion stage, the constant current output maintains the current (about 100mA) by adjusting the duty cycle

the advantage of xenon light source is that it can solve the contradiction between brightness and accompanying heat. It emits strong light when discharging, but many high consumption, low efficiency and other mechanical products in the flash market are gradually eliminated. The light duration is very short, so the heat impact is small. Due to the large instantaneous energy, the image layer polylactic acid (PLA) is a popular green high molecular material in the field of bio based and biodegradable research in recent years, and the secondary reduction is better. In order to prolong the service life of xenon lamp light source and improve the photoelectric conversion efficiency, in the case of low repetition rate, it is generally necessary to add the pre ignition current before the pulse high-power discharge. If the traditional power frequency transformer type precombustion circuit is adopted, the filter capacitance and high-power current limiting resistance must be increased, which increases the volume of the circuit, and the circuit is easily mistaken for removing precombustion due to interference [3]. In addition, when the xenon light source is working, the arc discharge time is long, and the energy release of the discharge capacitor is insufficient, which may lead to the phenomenon that the discharge capacitor cannot discharge normally. According to the working principle of xenon lamp light source, this paper presents a power supply structure of xenon lamp light source for igniting and precombustion, and develops the precombustion power supply of xenon lamp light source. The power supply is controlled by PWM technology. The ignition and pre ignition phases share a common power supply. It is a voltage source during ignition and a constant current source during pre ignition. The test results show that the power supply has high efficiency, reliable operation and stable operation. The xenon lamp light source effectively solves the abnormal discharge phenomenon caused by the residual energy of the discharge capacitor

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