The projector is an indispensable video output device in modern multimedia conference rooms and multimedia classrooms. Its role in the multimedia field is to amplify images for people to appreciate, which is incomparable to ordinary CRT and LCD TVs. Yes, it can project traditional video signals and computer VGA signals through the adapter onto the screen for people to enjoy and use. A projector is an instrument that projects light for everyone to watch. However, the lumen of the image projected by the light from the display screen alone is low, so in order to pursue quality, the manufacturer specially added a lamp as a light source. If you want to project it to a large place, it is usually on a wall or curtain without a light source. At this time, the role of the light is reflected. The function of a plane mirror is to change the propagation direction of light, and the function of a light bulb is as a light source. If the words projected on the screen are too small, the lens (convex lens) should be closer to the object (words) and the lens should be farther away from the screen. Projector lamps are mainly used as a light source for projection. However, the lumen of the image projected by the light from the display screen alone is low, so in order to pursue quality, the manufacturer specially added a lamp as a light source. If you want to project it to a large place, it is usually on a wall or curtain without a light source.