Introduction: HD Image Projector
This is an upgrade on the previous image projector that I made. I called it HD simply because of the improved image output.
Improvements on the previous image projector:
It now uses 2 lenses for a brighter image
Allows full adjustment of lenses and light source in all directions
It now uses a halogen spot light bulb for a super bright image even in daylight (warning, this bulb gets EXTREMELY hot)
What is this projector for?
This projector allows you to draw a picture/text on a transparent sheet and have it projected onto a wall. Alternatively you can project camera film, movie film reel etc.
What you need (this isn't an exact science, you can swap bits out with whatever you have laying around:
30" length of 2x2
30" length of furring strip (thin strip of wood)
2 magnifying glasses (or camera lens, fresnel lens, magnifying sheet, anything that magnifies really)
A light source; torch, bulb etc (I recommend a halogen spot light light source)
Nuts and bolts
Step 1: Test and Measure
Before doing anything permanent, you need to test your lenses and light source to work out roughly what the distance should be between them.
Arrange your items on the floor in the same line up as shown in the image.
What's the layout in the attached image?
Start by placing your light source, next a magnifier, then your image/drawing/film and finally another magnifier.
Move the items around until you get a clear image projected onto the wall and make a note of the distances between each item.
I tested with a macro camera lens, a canon 33mm DSLR lens and a magnifying glass, All worked perfectly fine. I also tested with a few different bulb types. I settled with a halogen spot light bulb since it provides the strongest and most focused light without having to buy specialised bulbs.
Step 2: Adjustable Lenses and Light Source
In this step, you'll be making the adjustable lens/light holders. Repeat this step 3 times for 3 duplicate holders (2 for magnifiers and 1 for the light source).
MAKE PIECE A
Cut a piece of furring strip to about 10 inches
Draw a 6 inch line down the middle, about 2 cm from the top (Picture 1)
Score that line with a knife (this makes it easier to drill holes in a straight line)
Drill holes close together along the line (the hole size should match the size of your bolts) (Picture 2)
Now is the tricky part, Hold your drill on it's side and push it down over the line you drew and the holes you drilled. The idea is to remove the wood between the holes so you're left with a rail that you can slide a bolt between. (Picture 3)
Sand down the hole and ensure your bolt slides freely inside it. (Picture 4 - Only 2 pieces shown. You must make 3 )
MAKE PIECE B
Now do the same as above but with a 5 inch strip of wood and a middle rail width of 4 inches. (Picture 5)
ATTACH PIECE B TO THE BASE
Attach piece B to your base (30" 2x2 mentioned in the intro) with two screws. Place a nut between the screw and the base to act as a spacer. Place a bolt through the rail hole, facing out. (See picture 6 and picture 7)
ATTACH PIECE A TO PIECE B
Drill a hole at the bottom of piece A and slide it onto the bolt of piece B. Secure it loosely with a nut. (Picture 8)
As mentioned above, you need to repeat these steps 3 times. Attach each adjustable rail (Picture 8) at the correct distances apart as per the measurements you made in step 1.
Step 3: Prepare and Mount Lens / Light Source
Prepare lens and light source for mounting
You simply need to attach a nut to each lens and the light source. You'll need to improvise depending on the frame of your items. For the magnifying glasses I simply glued a nut to the edge of each lens frame.
For the light source I glued a nut to a small piece of wood and secured the light fixture to the wood with rubber bands. This means that I can swap the light source out with torches and such like by simply removing the rubber bands and attaching the wood to the new light source in the same way.
Mount lens and light source to rails created in step 2
Spin a nut onto a bolt until it reaches the end. Slide the bolt through the top rail of the mount you made in step 2. Spin another nut onto the bolt from the other side. Turn the bolt into the nut attached to your lens/light source. (Picture 4)
The rail system allows full movement in every direction, allowing perfect alignment. (Picture 5)
Repeat these steps for each lens/light source - You should end up with something that look similar to Picture 6
Step 4: Ready to Project
For now, I'm holding my film reel sample (From Spirited Away movie, bought at Ghibli Museum, Japan) in place with some playdoh.
I'm considering coming up with some kind of wheel that can play animations.
Even in daylight, I can get a very strong image of a reasonably large size by using a 50w halogen spot light bulb. I want to test a 100w bulb but have yet to find a store which has them in stock. Unfortunately the pictures don't do justice to the brightness of the image, but then that's generally always a problem when taking pictures/video of a projector.