XGA Projector, Unique Folded Design, Ceiling Mounted, Long Throw

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We have built a LCD projector, XGA after studying various web sites and forums. For pictures of projector and Screen Shot, please visit our own web page by clicking the link - www.drtsolutions.com/Projector.htm
The projector uses long throw lens and is mounted at ceiling height 22 feet from the wall used as screen for 10feet wide image. It has all inputs including component video, VGA, S video, TV Tuner and easy keystone correction. It uses 13.3" XGA LCD, Metal Halide lamp 400W, 135mm triplet projection lamp and two small exhaust fans etc. Our study of various forums revealed that design of the enclosure should be such that it should be possible to adjust all the elements easily with precision and hence I made the enclosure with front opening for such adjustments and the projection lens is also mounted with similar adjustments. Overall results are excellent. The cost is nearly 20% of the equivalent commercial version with added advantages of a very cheap lamp, much longer lamp life, much longer LCD life due to enough ventilation etc. The only disadvantage is size but we have placed it on an almirah, top of which was already vacant. Hence the projector does not require any special mountings or space.
This project was initiated as our 29" TV was moved out and one of the rooms fell vacant. While studying alternatives, I studied diy projector sites, came across www.tomshardware.com and started building such projector after buying a junk overhead projector (OHP) from a local disposal shop for Rs. 1400=00 (i.e. $30). The metal halide lamp 400W was kept inside the metal enclosure of the OHP. The exhaust fan and the top glass remained as in OHP. The fresnel lens was taken out and mounted on four long screws. All trials and settings were made using a transparency of our own photographs.  Having achieved a satisfactory 10 feed wide image, we obtained a 13.3" LCD monitor. Taking out the screen was a challenging task. Finally we could do so after obtaining a special flat ribbon cable. LCD screen was placed on top of the fresnel lens. We got very good results but the projector was occupying centre of the room at a distance of 10 feet from the screen. Then we obtained the long throw lens, a reflecting mirror was mounted at 45 deg. long throw lens was placed in a wooden assembly having adjustments shown in the pictures. Thus the distance was increased to 22 feet from the screen with the projector placed on an almirah. In the meantime I studied various other sites and accordingly the unique design of the enclosure was developed. Now my grandchildren and other family members, relatives and friends are enjoying the theatre like atmosphere in the said vacant room..
Our web page www.drtsolutions.com/Projector.htm is constantly updated based on queries in different forums.
 
Uniqueness is on account of most easy adjustability of all elements. Further uniqueness is innovative front opening. Many of the new comers experience difficulties in getting image due to not having such adjustments. Further due to such adjustability, the projector can be placed in any location and optimized. Such design was developed after studying problems expressed in various forums relating to diy projectors
 
Pictures of Projector and Screen Shots

The pictures of our Projector and Screen Shots are attached. by using the unique front opening all the elements inside can be easily adjusted and optimised. The projection lens is also adjustable to an fro as well as up and down. In one of the picture, the projector is shown to be placed on top of an almirah. The wall screen in the same room is 22 feet away. One of the screen shots is from an Indian movie. Two other shots are 3D pictures taken by me with my grand daughter standing in front of the screen. For more details on above, please visit our web page by clicking here:-
XGA Projector
 

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in Fig. 3 - Long throw lens assembly,

how is the lens secured to the wood inside. What I mean is when this mount is secured to the rest of the box you want to slide this entire mount away and towards the box to focus. In order to do this the mount show in figure 3 would have to lock the lens in that wooden hole. Another words the lens cannot slide withing the hole of the mount. These lenses dont have any mounting points. So how did you secure it there so it does not rotate or slide withing the hole?
 
On 24.02.06 we shot the following pictures of the screen 120" wide at 22 feet from the projector placed at ceiling height on an almirah. Wife Padma is standing before the screen. The pictures are quite bright and brightness can be further enhanced as it is at 50% default value of LCD. The digital camera is set at auto with ISO 50 setting. The reflector has been made out of a bowl which was got nickel plated.
 

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