Teaching projector as a liquid crystal projector, Projection Machine
Keywords: projector transformation
Be
Author: Chen Lidong
The teaching projector is also known as the transmissive projector (national standard product name). At present, the domestic liquid crystal projector will move the optical structure of such a machine, but only have some improvements. There are a few ok, using a teaching projector to make a liquid crystal projector. One is to reduce the difficulty of production. Reduced production procedures and shorten the production time. For friends who are interested in making their own hands-on ability, the teaching projector is mature product, the use is safe and reliable, and the design is reasonable, no need to renovate, but also make many optical principles Unfamiliar friends take a lot of detours. Second, for friends who like to do hand, use teaching projectors to make a projector can be easily replaced with LCD screen, which is conducive to future experiments and upgrades. This paper introduces all the processes of the projector to make a project, for friends who are interested in making reference. First, you must purchase a teaching projector. The size of the projector can be selected from 250 × 250 mm, which is not affected by the length of the 10.4-inch LCD screen. If the model of the 200 × 200mm tablet is selected (the model is relatively rare), the 1O.4-inch screen cannot be completely displayed. There are approximately 1 cm to each other on the left and right sides of the screen. But this projector is small, low price, or consideration. Here is a 250 × 250mm panel product produced by the Nanjing Machinery Factory. The machine uses 250W / 24V halogen lamp, the price of the bulb is 8 yuan, and the life is about 100/ hours. Two bulbs are installed in the machine, and the conversion is performed by a mechanical chaler. If a bulb is damaged in use, it can be easily converted to another light bulb without having to replace it immediately, very practical. The lens of the projector has two types and multiple pieces, and the preferred is of course multiple sheets, but if you can buy a single-chip, you can also purchase a concave structure due to its lens. Its imaging quality is much better than the flat convex and double-convex structure we are often seen. The model purchased by the author is single-chip, the focal length is 290mm, shorter than the diagonal length of the panel, and is wide-angled. Regardless of the model and the lens, you should turn on the power when you purchase, check the projection effect, the method is: Align a white wall, the distance is 2 to 3 meters, adjust the focus handwheel, when the panel When the projection of the edge is the clearest, it is clear that the image has a rainbow like a colorless scattered i bright and dark, and the deformation (concave or convexes toward the center). If the up and down broadband occurs, the mirror is not 45 degrees. ~ Do not appear to be avereminated, while dispersion is within 2mm. Because this is the edge of the picture, it is also inevitable, let alone the LCD we use will be smaller than the size of the tablet, so this phenomenon will be reduced in actual use. Check the time to be short as possible. Just when contacting the projector. It is often found for curiosity, and no items are set up. This is incorrect (there is also the same warning content in the projector's instructions, so we must read the instructions carefully), especially in the mirror When you open! You only have to feel it with your hand, you know why: Turn on the power, put your palm on the table, only a little temperature, slowly put your palm to the lens, feel the temperature will get more and more high, There will be a burning sensation at the bottom of the lens. The temperature above the lens is higher. It is enough to ignite paper, matches, and if the mirror is placed horizontally, it will be burn down, but as long as it places a small slide on the panel, it will greatly alleviate. Then, under the illumination of strong light, the mirror will look very dirty, then it is possible to wipe the cloth or liquid of any material, and can only be blown with a balloon. Purchase the projector, then choose the LCD screen. Also get a larger size projection screen, but also get the highest brightness, 10.4-inch screen is first choice. With a LCD screen, you have to give it a housing to protect the LCD is not damaged in use. It is not difficult to make a shell for the LCD screen. Place the screen and decoding board, the tank, and the control panel on a plane and try to close. At this time, you should pay attention to the annections and up and down. Because the front of the screen (the correct direction of the screen is displayed during the correct direction of the screen) is facing the lens, the front side faces the projection panel, and the screen is directed to the direction of the screen. Then measure the length width size they occupy, add 2crn each with this size, and make an interior. The thickness of the frame is tone. The frame must have a certain strength, the material is not limited, preferably insulating material. The material of the frame should not be too thick, so as to avoid the shell of the shell and the lens support rod on the projector, it is impossible to put the screen to the main position of the panel, and there is no problem within 2 cm. Make a panel with the outer dimension of the frame, preferably use plastic or flat thin wooden board. Both the panel with the box with "302" AB rubber, load all parts, then dig out a length of the same size as the display portion of the screen, and the housing is done. Put the screen with the holes on the casing, stick to some hooks around the screen to secure it with the panel. The same method is used to secure the components such as decoding plates to lead the power cord to the AV line. Place this frame on the projector panel and place the screen in a proper position. Check that there is no leakage around the shell and add a trapeze. Open the LCD power supply and signal source, turn on the projector power, adjust the mirror to 45 degrees. Turn the rocker hand wheel, the image will appear on the curtain. After a few minutes of opening the projector, to monitor the temperature of the LCD screen, the low-light liquid crystal screen often causes damage due to heat absorption. Therefore, it is necessary to place a size of about 10 x 10 cm next to the screen. After adding the wind, the temperature of the LCD screen is very low, then you can sit down and enjoy the happiness that the big picture is brought!
Our other product:
