DIY- homemade projector

Step 2 How to begin

to begin get your box and cut the top off then about halfway down put a piece of cardboard with the fresnel lens in it and firmly tape it down (see pic) cut out another piece of card board the same width as the box and cut a hole in it for your light the cardboard around the hole should be covered in tin foil to reflect the most light. insert it in your box make sure it is in line with the fresnel lens and should be at least 3inches away from it. (update) i just learnt that if you want to make the picture about 3x brighter you need to put a cone + condenser lens/strong magnified glass on the light (see pic)

Comments

[jothi.instru]

hi.... can u say wat is that fresnel lens mean... is those available in shops...

[simbu.rm]

hi Fresnel lens very low cost of ebay.in for just Rs.675/- only

simbu

[porkypinekiwi]

yes you can get it in a shop its some times called a credit card sized magnified glass. its just a piece of plastic with lines on it that that makes it a flat magnified glass. ill put a new instructable up soon to make it easier

[zahmed1]

when the screen gets projected onto your wall how many inches can it go? will it go to a size of 100 inches from a distance plz tell me cuz im setting up a home cinima with a limited budget

[porkypinekiwi]

you could make it go to 100 inches but with the light im using you wouldnt be able to see much (it would be VERY dark)

[bcrawford-1]

is their any small electronics that you can take apart for the lcd? like an ipod or portable dvd player?

[porkypinekiwi]

yes, anything with a flatscreen will work, but it needs to be working when you take it apart. it just takes the screen and makes it bigger.

[haguayo73]

how annoying is that you have to login to see large images

[-max-]

thats why i NEVER log out! *,* U

[porkypinekiwi]

yea i know !!! even i do to see mine!!!

[dbuilder2]

is a condenser lens needed?

[porkypinekiwi]

no it is not needed but highly recommended because it makes it alot brighter.

[007.sammy112]

 please tell me the distances between light and maginifing glass and lcd

[porkypinekiwi]

to be honest i dont know and it depends on how big your screen, light and  magnified glass is, first you need to get the light focused on the screen using a condenser lens (a magnified glass) but dont put it so close so you can see the light( i am using leds and if its too close you can see the led pattern on the projected image) just play around with  it.

[DrNerdington]

I'm no projector or optics expert, but I don't think the foil is a good idea. Rather than reflecting useful light, it will just add to "spurious reflections" that end up as light pollution that tends to wash out the picture.

[porkypinekiwi]

in my original model i just used cardboard and when i put the foil in it really made it brighter and did nothing to the picture there is only one way for the light to get out and thats through the lcd/fresnel lens

[DrNerdington]

Well, I can't argue with empirical evidence, but that contradicts what I've read about the light path of a projector (and the logic of how lenses work).

If I ever get around to building one, I'll be sure to experiment in this area. 

[Ahmedqatar]

This is amazing .. i agree with DrNerdington about the usage of foil  .. maybe using another type of material to reflect the light is better .. like a mirror or so!

[porkypinekiwi]

yes i think a mirror is a very good idea but im just using what i have at home maby later ill get 1