LEPV (benefit is sent) the brightness that Bai Jing soft act promoted whole and umbriferous system through increasing screen gain, although match the low brightness projector of 2000 lumen, also can achieve the expensive loud system of 6000 lumen, big political integrity made an appointment with what Gao Liang spends projector to purchase cost. In use process, because projector brightness is reduced, power comsumption is reduced, can save power consumption effectively, save expense of charge of electricity thereby.