When the laser video projector works, it is in a heat balance state under the action of the cooling fan, which is related to the external temperature. When the external temperature exceeds a certain temperature (mostly 35 - 36 C), the temperature of the important parts of the interior will also exceed its rated value. Important heat sink parts have their own temperature sensors (such as near the liquid crystal, above the bulb, on the radiator of the power supply). Once the temperature reaches the critical point above the region, the protection program inside the projector will start and automatically shut down the projector. This is the basic working principle of the radiation system and high temperature thermal protection function of the projector. This function ensures the longevity of the projector to the greatest extent.
The physical properties of the LCD projector's core component, the LCD plate, determine that its working temperature is not allowed to be too high. Once the temperature exceeds its endurance range, other optical components will be damaged, for example, the polarizer near the LCD will be deflected at higher temperature. In addition to the optical system, the switching power supply of laser video projector is also an important heat source. The switching power supply undertakes the task of supplying power to the projector circuit and to the light bulb.
In order to use laser video projector safely, heat dissipation and high temperature thermal protection function become a design requirement that all projectors must consider. In the LCD projector, the fan set is used to heat dissipation for the core part of the projector and the main heat source such as power supply. At the same time, in order to ensure the life of the projector, the temperature sensor installed in the projector monitors the temperature change in the projector in real time and feeds back to the processing circuit.