In-depth understanding of what parts of the projector is composed

2021/03/27

Now whether it is a home theater type, a portable business type or an educational conference type projector, it has become a portable device that we often use in our lives. Do you know the projector you often use? let's take a look at what parts the projector is made of.

 

 

 

(1) The projector’s Condenser system


The condenser lens of the projector is mostly a threaded lens, also called a Fresnel lens, which is composed of two thin flat plexiglass plates engraved with concentric circular threads, which functions as a large-diameter convex lens. The threaded lens has the advantages of large diameter, light weight, and good light transmission. The disadvantage is that the temperature rises above 70°C will cause deformation.

In order to reduce the surface temperature of the threaded lens, a crescent mirror, also called an auxiliary condenser, is placed between the light source and the condenser. It can not only block the radiation of the heat energy of the light source to the threaded lens, but also expand the containment angle of the threaded lens. There is a glass on the threaded lens, which can not only show the projection film, but also write, and can also be used as a demonstration of some experiments or teaching aids.


(2) Plane mirror
The projector is equipped with an adjustable plane mirror to convert the vertical optical axis from the condenser into a horizontal optical axis. Therefore, the slide is changed from vertical to horizontal, and the enlarged positive image is obtained on the screen, so that the teacher can face the students while explaining and presenting, which is very convenient. The projector must be turned on before turning on the flat mirror to ensure that the light emitted by the light source is directed to the screen after turning on, so that the light spot appears on the screen; if the flat mirror is not turned on, it will reflect the light emitted by the light source back to the screen after turning on the projector. The light source increases the temperature inside the machine and the surface of the light source and affects the life of the projector.


(3) Other parts and circuits of the projector
There are some important electrical equipment and ventilation equipment in the projector. Among them, the transformer converts 220 V mains power into 24 V AC voltage for projection light bulbs. Projection bulbs are mostly 24 V/300 W bromine tungsten lamps, and a lot of heat is generated during operation. If it is allowed to accumulate, the temperature inside the machine will inevitably increase, which will damage the threaded lens and electrical equipment. Therefore, the machine is equipped with a squirrel-cage fan to discharge the heat from the machine in time and reduce the temperature inside the machine.The rotating focus button will drive the projection lens and the plane mirror to move up and down in the vertical direction, changing the distance between the projection lens and the object (projection film), and realize the focusing process. In addition, the elevation angle of the plane mirror is adjustable, and the height of the image on the screen can be adjusted by changing the elevation angle. The mirror can also be rotated 360 degrees in the horizontal plane, so that the image can be projected on any wall of the projection room without moving the body.

 

The projector, like the slide projector, also uses the principle of convex lens imaging to project a transparent object onto the screen to form an enlarged image. The projector is mainly composed of an optical system, ventilation equipment and circuits. The structure of the projector and its usage The slide projector is similar.

 

 

Dongguan Yingjia Electronic Technology Co., Ltd.A high-tech enterprise specializing in the research and development, production and sales of electronic products such as LED projectors, vehicle-mounted HD driving recorders, driving recorders, 360-degree driving recorders, hidden recorders, driving recorders, GPS navigators, etc., We have our own R&D team, and our products have been exported to Europe, America, North America, Southeast Asia and other countries.