DIY Projector using an OHP

This is another projector i made about 2 years ago, but i still have fully working.

I don't have a lot of time to tell you what to do step by step, and my English is really bad, but i have lots of pictures that may help anybody who want to make one of this cheap (under 50 UK Pounds)

If you have any question... Just ask, I'll be glad to help.

Comments

[alexr15]

 hi i dont get one thing.

 so first light source then condenser lens  then fresnel lens  then lcd and finally ohp lens (i wont be using a mirror) -- is it the right order or i am missing somenthing  --. hope you will answer

[newtonn2]

Yes, thats the way it goes.

[newtonn2]

Hi there. The fresnel lens is from the ohp, both of them. The OHP has two lenses together, you could keep them together and place them just b4 the LCD, that wont let you adjust the keystoning. If you separate them and place one after the LCD and make it able to till, you will be able to adjust keystoning.

[cd isp]

can i attach lcd and OHP fresnel lens,and then they are connected to a holder,so that lcd and fresnel lens will move.will this help in adjusting key stoning effect.

[newtonn2]

To adjust the keystoning you will need to fix the lcd and connect the fresnel in a way you can tilt it

[alexr15]

 well thats my problem cause i dont have an ohp. i bought a very strong light source( oh and do i still need an condenser lens since my halogen lamp comes with reflector and some sort of plastic in front, probably with the same effect of a condenser lens??)   , i have an  ohp lens (triplet) and 7" lcd , but no fresnel lens. and the only one i found to buy are not ohp lens but simple one also called magnifying glass . is this good?

[ElvenChild]

Hello, would you mind disclosing the dimensions of the enclosure? Thankyou for your time, bye!

[maxpower49]

one more question what order dose everything go as far as the lcd panel frenel lens and the glass

[maxpower49]

ummm instructables took out the annoitations you had on each slide

[newtonn2]

Ohh nooo. I try to edit the sideshow to see if I could fix it there. But all the comments seams to have desapaired.

[maxpower49]

it's alright.. lol as soons as i get everything i need to make this project another problem appears

[Abhineo]

Hi Newtonn. First i would like to give you thanks for sharing you knowledge in the world and i impressed with your projects. However i have some minor doubts on creating my own projector. Appriciate if you could clear those. I bought a Appolo odyssy 11000 OHP from US through one friend, but in india it requires 50$ (2000 rs /-) voltage converter to operate. I took converter from one friend and it didn't booted up. its bulb power is 410w/82 V. Looks like some problem is in its PCB. however replacing the production and getting back another i thought of some alternatives, but want your opinion please. * I could replace the PCB and the bulb by indian voltage (230 V) operated MH 400 Watt buld, that is not costing me more than 50$ here including ballast with inbuilt capcitors. so that would run in indian voltage without converter. But i have doubt on running its 2 fans that look like CPU fans but couldn't get volt / power rating on it. Please provide me your thoughts. * Due to its portable design, i am thinking to use its own cabinet for LCD projector by using 7" car lcd dvd player. i have attached the pics of projector, but can you please give me a rough diagram for placing lenses LCD mirrors in side the cabinet. Please provide me length width in inches for cutting the fresnal mirror and glasses for best outcome. here is specifications of projector. http://www.mmvideosystems.com/video_equipment_rental/equipment_detail/apollo_11000_odyssey.html And i am going to use 600x480resolution below LCD screen http://cgi.ebay.in/ws/eBayISAPI.dll?ViewItem&item=120610726143&fromMakeTrack=true Spec - Item Description TFT Active Matrix Mobile LCD Monitor Built-In Dome Light Use 7" TFT LCD display panel Super High quality Picture High Resolution Display Wide viewing angle: 120 °horizontal 100°vertical NTSC/PAL Auto Switchable Full function remote Power consumption: 8W Power supply: 12V DC * - I have doubt on using condenser lens, the projector have not any, where i could get and what type? I am very sorry to asking may be very minor things but i am a newby here so please assist. Thanks, Abhishek

[newtonn2]

Sorry for a very late answer. Before anything... Do you still need some help with the projector?

[ashhroxy]

Hello! Newton. Your projector is impressive. Could you possibly tell me the weight and dimension of your projector

[Abhineo]

Also, Have you used any uv/ir filter? i heard projection get awesome results by using this? It is very costly to get so want to confirm that before buying?

[raun123a]

did u use a ballast didnt see ne could u give me a quick tip as to how use one

[mackintoshlinessless]

hi newtonn just quickly but what is the diameter of your triplet lens and the magnification if you know that too. thank you :)

[newtonn2]

 I'm not too sure. I think the focal length is about 300mm.  It came out of an OHP, maybe you could use the lens from the OHP you got.

[mackintoshlinessless]

sorry i dont really understand what focal length is but is the lens say more than an inch? by the way is a resolution of 800 by 600 enough for a good viewing experience?

[hantly]

 hi there 
i could realy do with some help i have dismantled my ohp!! the transformer has seven outputs and one of then doesnt have any wires but that is not the point its just that it ways a tonne. that means the projector will do. i mean does yours and if not i dont think i need all the outputs is there a lighter one i could use? i cant say the voltage really. the brown wire says 240V and the blue one common! 

[newtonn2]

 
Sorry for really late answer.

Mine is really heavy too. There is another way to do with is buying an electronic transformer. But they are soooo expensive, it makes the project not worthy any more if you have to buy it.

Mine is heavy, but I didn't need to move if front it's place so once is fitted, you don't worry about the weight any more.

[mackintoshlinessless]

i cant wait to build one of these but the only problem is that i cant find ohp's anywhere not even on ebay (80 dollars+ ). BTW how did you cut the frezel lens out becuse it wont load that picture. Also how big is the dimentions of your lcd screen and cut out lens. thank you

[newtonn2]

 I don't remember the side of the fresnel lens once is cut. cut it a bit bigger than the LCD. All depends on how you are going to fit them.

[mackintoshlinessless]

is this a good monitor to use:
http://cgi.ebay.com.au/A47-New-7-Inches-Headrest-LCD-IR-screen-IR-Car-DVD-TV-/220596436088?cmd=ViewItem&pt=AU_Car_Parts_Accessories&hash=item335c927c78
thankyou, btw where else can you by a a triplet lens from?

[newtonn2]

 Hi, sorry for late reply.

The LCD is not bad, but you could probably find one with better resolution.

[noik]

 Best projector I've seen on instructables.

[newtonn2]

 Thank you!  Did you see my other projector using a LED as light source. 

See here

[noik]

 Yes, I saw, I'm going to make one to:)

[mackintoshlinessless]

struggleing to find a cheap OHP???? ask the teachers at the wood, metal works because usually the school asks them to repair them but i asked and got two for free. all that was wrong is that both bulbs had blown. good luck

[matthewkhoury75]

hey newtonn, its me again. on my small projector, I have wired everything up to the laptop charger and the switch and it all works.  I am putting everything in the box and was wondering were you got the screw in this picture http://www.instructables.com/file/F4MDADPFRXWGXGF from? I need something like this and was wondering if you know were i can get one? I have a cd drive but dont know were it may be in it? Please reply asap.

thanks in advance

[newtonn2]

 Hi there Matthew, nice to hear from you.  I'm glad you have your projector almost there.

Could you please let me know what part of the screw you need?. As I made the components that the screw is holding. 

[matthewkhoury75]

Hello newtonn, I am almost finished with my projector, all i have to do is drill a couple holes and put everything inside the box.  I would really appreciate it if you could tell me how you made those screws. It would save me alot of trouble to use those screws to hold the lcd in place and the condenser lens than glueing them or some other sort of permanent hold which would make it nearly impossible to replace the light.

Thanks,
Matthew

[newtonn2]

 I made them with a screw, and a aluminium cylinder.  I find then and make the thread on the aluminium and place the screw. the pictures says it all. I have not more info I can give you about it. I just made it out of part I had around.

[matthewkhoury75]

Do you have any pictures of the aluminum cylinder itself or a picture of just a random aluminum cylinder? I do not really understand what it is. A picture of it by itself would help me understand where I could get one.

Thanks,
Matthew

[matthewkhoury75]

Hey newtonn, not to mean or anything but the sooner you can answer my question the better.  If you are confused about something could u just tell me how you made the hole screw assembly.  As I said below, i need some way to mount the condenser lens and hold it in mid-air and i may use another screw to hold the lcd.

thanks,
matthewkhoury75

[matthewkhoury75]

I need the clamp at the end of a screw to mount my condenser lens, I have a small condenser lens, so I cannot glue it to the edge.  I would also like to use it to hold the lcd in place.

[alexr15]

 i am having a lot of trouble with heating. i dont get it how yours could stay at 30-35 C.  i am using a 500w halogen bulb.  i have 2 tempered glasses between the light source and the LCD , and i also have 3 fans(2 between light and tempered glass and one between glass and fresnel) all of them are blowing air OUT of the box ( should i put one to blow in?? though i tried this and still didnt work) and still the temperature goes way over 50C after 10-15 min.... what else should i try ( except from changing my light source since i dont want to sped any  more money on this project) . looking for an answer.

thank you

[matthewkhoury75]

Hi, I have made a projector like this before.  My light was 400w 36v and it was cool enough with two fans.  First make sure that your fans are good. If you can barely hear your fans when just one is on, then you may need to get new fans.  If you fans have three cords coming out: a red, a black, and a yellow or white as the last one, then I would try to replace the fans because they are very slow.  Second, all of your fans should be blowing air in and there should be some kind of opening where the air can escape. I hope this helps.

[newtonn2]

 
Hi there!
It's going to b really difficult to use that bulb. I used a 250w OHP lamp with it does get hot, but not that hot. There is other ways to cool down the LCD. Could you send me pictures so I can give you more help?

[alexr15]

 yes i will post some pictures but it will take  a while. i dont have any right now. i am working at this only on weekends since i work pretty far from home... any way next weekend its easter so ill take a break but most probably the weekend after :) , in case i dont find any other solution till then, i will post some pictures.

ps; i just saw a 85w cfl bulb (compact fluorescent bulb) that they says its equivalent to more than 400w (incandescent). the con is that its pretty big (25-27 cm long). the pro that its really cheap (8,99e) . i will try to use one of this with a lamp and if the resutl is goog porbably i will stick to it ( although the projector will be more than huge :)) )