Help with planning a project. DIY projector

Alright, so I realized that I could make myself a projector which is much cheaper and probably nicer than what I could buy, only it would cost much less to make it myself. I am curious about the quality of the picture, but I don't think that I will be able to find out how it looks without just going for it myself. The plans are fairly straightforward for the main parts, but the devil is in the details. The way that it works is outlined in the first link below. Essentially, we take apart a laptop screen and replace the stock backlight with a very powerful one (a 100W led), and then add on a lens for focusing, throw it all in a box and bam. Projector made.

Now, for the minutia. First, lets look at the led. I would like to make the led removable in my own personal build so that I would be able to use it as a flashlight whenever needed. However, rigging that up to the power is something that I have not quite figured out yet, but we will get to that in a bit. Here is the how-to video about building a flashlight with a 100W led which would work in a projector like this.

And now for the laptop screen. There are two ways to do this, that I can see. First, you can do what Logan and Wendell did and use a spare screen, a controller board, and possibly power from either a laptop style adapter or a home-made molex-to-round adapter, which is what they did. I am not sure exactly how they went about making that power cable, and I don't know how to make sure to get the right plug for the round plug, but I am sure that can be done easily enough. A little soldering never hurt a project. The second way to do this that I see is to use a whole laptop and basically convert its screen into a projector. Dismantle the screen, stick it in the box, attach the body of the laptop to the projector's box and bam, you have a self contained projector based pc. That eliminated using it for your cable tv, unless you find some sort of adapter which I am sure is possible, but a simple controller board for throughput would be the more straightforward solution, though not quite as cool, imo. Below is the link to the video that Logan and Wendell made about using a controller board and whatnot. Using a 15.6" screen seems..... inadvisable based on the schematics in the first link, though that is more readily available and is in fact what my spare laptop uses, so it is what I would likely use in my own build. Should it work ? If the light is directed over the screen correctly, it should work all the same so long as I can get it to focus, I imagine, but this all seems more problematic than necessary.

And now for the confusing bit. The power supply. I think that the most simple way to go about it for a simpler, throughput style projector (which uses the controller board, not a laptop) would be to put a power supply inside of it and run both the screen and the led off of it. However, rigging that up seems a bit of a hassle to me. I imagine that you would need to use molex or something to power the led, but I don't really know the best way to go about this. As you might be able to tell, I don't have too much experience. The right boost converter thing should allow the use of a sata power from the psu to work, I believe. And as the boost converter used in the video from DIY perks above (about the led light) allows for conversion between 12V to 30V it should work for going from sata (12V) to the led (26-30V). Then a molex to round for the laptop screen. Next a switch would need to be made to power on the psu. If I am not mistaken, this can be done by shorting two pins on the 24pin connector. Easy enough to solder together a power switch off of that. The problem then becomes working it so that the sata power is able to charge the batter which would be on the led unit for the flashlight aspect. If done with an entire laptop instead of a controller board, a separate power supply would be needed for the led, though that is how it is made in the video above, so that shouldn't be too much trouble.

And finally, the bit that I just don't know about. Maybe someone here is more knowledgeable about optics than I am, but I believe that I should need a lens to focus the image coming from the projector (which would then flip the image, but that is fixed by mounting the screen upside down). Only problem is that I have NO CLUE what kind of lens I should be looking for, how much it would cost, and where to get one (amazon preferably).

From my estimations, a build like this one, with a removable led flashlight, a laptop screen, a controller board, and a pc psu should run somewhere around $300 US (if in the US at least, which I am). Considering that those leds are rated at ~7000 lumens, that is one hell of a deal for a projector, assuming that the picture is halfway decent, which I imagine it would be.

Anyway, input and thoughts are appreciated. Obviously, I am not afraid of having to do any soldering work or anything like that, so whatever suggestions you might have for a build like this are welcome. Also, if you have reason to believe that this wouldn't even be worth the effort and money, let me know as it could save me that effort and money.

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