I think many people would like to have a home theater in their home. If you have already thought about this, then you must have come across the question - how to make a big screen? If you buy a TV, it will cost a pretty penny, and even a large TV with a diagonal of one and a half meters will not create the impression of a cinema. Another option is to buy a projector. Of course, the idea is also a lot of money, plus you can hardly find any components, and if you do, they are expensive. I mean the projector lamp, and it does not last long.
But when using a real projector at home, you can create a real cinema.
There is a third way that I went - to make the projector myself. To the article, this does not matter, but I will still tell you why I decided to take this step. I had a dream floating in my head for several years to build my own home theater. And then a girl appeared in my life ... And you can’t even imagine what a desire I had to invite her to watch a movie at the cinema. In our seedy town, apart from numerous pubs, there are practically no sights, but only heard about cinemas here. So I decided to build my own.
In general, whatever the goals are, let's get started.
Details and accessories.
Having rummaged through the Internet, I ordered the following with delivery by mail: two fresnel lenses with a focal length of 220 mm and 317 mm, an 80 mm / 1: 4 / FR = 320 lens, and the heart of the projector is a 15 mm LCD matrix with a resolution of 1024x768.
I ordered a case at the sawmill, designed it myself, so a lot of shortcomings were revealed during assembly.
Light. Powerful LED and driver for it. LED power 100W. It was all sent straight from China.
Assembling the projector
First, let's take a look at the monitor.
And very carefully remove the matrix itself.
An anti-reflective film is located on the front of the matrix. Of course, you can leave it, but I preferred to remove it, thereby improving the image quality.
It is removed like this: covered with wet napkins or a towel and left for 10-12 hours. Then it is carefully removed.
Checking the functionality, after removing the anti-glare.
Everything is working. Now let's start assembling the case.
We customize the wrappings on which the matrix and fresnel lenses will be attached
We attach the lenses with ordinary self-tapping screws, with the ribbed side of the lens inward.
Yes, I also forgot to say about buying a radiator with a cooler from a computer. I installed an LED on this radiator, before lubricating the surfaces with a heat-conducting paste for better contact. For reference: a powerful 100W LED is equivalent in light intensity to a 400W metal halide lamp.
We insert and attach the driver and heatsink to the case.
We check and are a little disappointed: our Chinese friends sent a defective LED - one section is off .... Oh well .... Plus, the driver is heating up, and decided to reinstall it.
We rob our box with lenses, insert the matrix in the middle. The image matrix must be rotated 180 degrees relative to the top and bottom and flipped. In other words, where the top is, there should be a bottom, and where the left edge is, there should be a right edge. This is done to ensure that everything is projected correctly, since the lenses flip the entire image.
We fix. lens with a focal length of 220 mm to the LED.
We turn it on and empirically find the place where our box of wrappings is attached, so that the light is distributed evenly across the screen.
Here I got a good picture when projected onto a wall with wallpaper. diagonal 2.5 meters.
Watching movies at home on the big screen is a very common desire. But its realization is noticeably expensive for most dreamers. Otherwise, they would simply buy either a projector or a TV. But for those who understand the design of electrical appliances, it is quite possible for them to independently make a projection device for a home theater. This will be discussed further.
A bit of theory
First, let's look at the diagram of the correct projector. Obviously, not everyone can make such a device. If only because it will require several accurate and high-quality factory-made optical parts:
- lens;
- lenses.
The uniform distribution of light on the screen will depend on them. Light must enter the lens at the correct angle. If you do not know the optical characteristics of the lens and lenses, all distances can be determined empirically.
The source of the image in the projection device is a matrix on liquid crystals. They work for the light. Moreover, each pixel on the screen is projected with an increase in size. Therefore, the original image should be as clear as possible. The more pixels the better. The so-called FULL HD is 1920×1080 pixels. The brightness of the projection lamp will determine the maximum screen size on which you can watch movies with acceptable brightness and contrast.
The simplest projector
If the reader owns a smartphone or tablet with a bright screen and a resolution close to FULL HD, and also dreams of watching movies on a big screen, he can try to make a simple device out of a box, a lens and his gadget. The box-body should be larger than the gadget in any cross section, and the lens should be commensurate in diameter with the size of its screen. But the distance to the screen will depend on its focal length. The idea is simple:
- a hole is cut in the box for the lens;
- a gadget is placed inside, which can be brought closer or further away from the lens.
The gadget is installed in a mandrel, which is convenient to move in the box. For a mandrel, another box with smaller dimensions can serve as a perfectly suitable blank. The reflection of light from the walls of the boxes should be minimal. To do this, it is best to glue the surfaces with black velvet appliqué paper. Or paint with black matte paint. Instead of paint, you can use a thick black shoe cream. It is best to lay guides between the walls of the boxes, especially when using velvet paper. They will protect painted surfaces from rubbing.
That's the whole projector. See the details in the images below.
Painted box-case
The lens is applied to the body and outlined with a pencil.
A hole is cut along the line from the pencil with a sharp knife.
A lens is inserted into the hole, which is glued along the contour
We place the carriage inside the box-case and use the projector
The result that we see on the screen is highly dependent on the size of the image on it. If the size is reduced, the brightness and clarity of the frame will improve. The image quality in this simplest projection device is at the “better than nothing” level. But the reason for this is obvious - a higher brightness of the image source and additional optics are needed.
High quality homemade projector
Next, we will tell you how to make a projector with your own hands, observing all the requirements. You need to start by disassembling the gadget. It is dismantled with the preservation of its performance so that the liquid crystal matrix of the screen is available for transillumination by an extraneous light source. If you cannot do this, then building such a projector is not for you.
Used parts:
- LED power supply board;
- LED 100 W (light source with minimal dimensions has an advantage);
- fan power supply board;
- fan control board;
- intermediate lens;
- output lens;
- gadget control panel via Wi-Fi;
- two intermediate Fresnel lenses;
- liquid crystal matrix from the gadget.
Radiator Mounted LED
Demonstration of the effectiveness of the Fresnel lens.
An intermediate lens is placed between the LED and the Fresnel lens in order to reduce light loss.
Elimination of projection distortion by a matrix suspension with lenses with horizontal and vertical deviation
And here is the result of the work done. The distance to the screen is 4 meters, the diagonal of the frame on the screen is 100 inches. Everything is clearly visible.
Based on a slide projector
But there is an easier way to create a projector. To do this, you can use a projector for slides that are projected from a sheet of A4 paper (overhead projector). Since all the optics are already in place, it remains to attach only the image source to it. They can become a monitor matrix. It will have to be disassembled to maintain performance. Since after installing the matrix in the projector, the monitor, as usual, is connected to the computer. It is best to use a projector that shines through the slide rather than using reflected light.
What happens as a result of this hybridization of a monitor with a projector is shown in the images below.
That's all there is to it. Unless, of course, you have such a projector. What kind of visibility is obtained on the screen as a result, the image below demonstrates.
The size and quality of the frame on the screen are very good. Moreover, there are projectors for projecting small slides that are commensurate with the screen of a smartphone. They are cheaper. Therefore, you can buy a smartphone with a broken screen and a faulty projector for its matrix. And what should happen as a result, has already been shown above.
Did you know that with the help of an old box and stationery you can assemble a home projector for your phone with your own hands? This is an easy and fun experiment you can do at home.
There is a lot of information on the Internet about this, but I put everything together and wrote down the finished instruction.
Step 1: How smartphone projectors work
There are two main types of projectors. All of them come with their own features, strengths and weaknesses, but most work on LCD and DLP technologies. LCD is an older technology, but that doesn't mean it's becoming obsolete. LCD stands for Liquid Crystal Display. The way it displays the picture on the screen is exciting and not as difficult as you might imagine.
The light bulb is tuned to transmit a fairly powerful light through a prism. A prism breaks light into its component colors, which are sent through small LCD screens. The screens themselves send out signals that pass through specific pixel locations. The light is then projected through the lens onto a screen where the images can be seen by the human eye. DLP, Digital Light Processing, or Digital Light Processing, is a bit more complex.
This time, the light passes through a spinning color wheel on a chip that is equipped with hundreds of thousands of tiny mirrors. The mirrors are switched off or on by electronic impulses according to the need at that moment in time. Although only one color is displayed at a time, the other follows it so quickly that it looks like the primary colors are blending to the desired color.
The image appears to be constantly glowing, when in fact, small parts of it are constantly flickering. This technology was developed by Texas Instruments and is based on older technology used for color television in the 1950s. Knowing the difference between these two types of phone projectors can be important as LCD is considered better for static or high contrast images. DLP, with its brighter colors, is considered more suitable for video.
Some DLP projectors are known to exhibit the rainbow effect. This can happen when white objects move against a dark background, at which time small shadows of red, blue or green can be seen. Most modern DLP projectors have overcome this problem with multiple chips and faster color wheel speeds.
Step 2: Things We'll Need
Materials:
- Magnifying lens (loupe)
- foam panel
- Smartphone
- Glue stick
- PVA glue
- shoe box
Tools:
- hobby knife
- hot glue gun
- cutting knife
- Hacksaw
- Ruler
Step 3: Cut the handle off the magnifier
Carefully cut the handle off the magnifier with a hacksaw.
Step 4: Reinforce the box
Reinforce the box by gluing the doors and corners.
Step 5: Let the glue dry
But do not get carried away too much, a few minutes is enough.
Step 6: Positioning the Lens
Place the box upright. Place the lens on top and center. Using a pencil, draw a circle around the contour of the lens.
Step 7: Cut out an even circle
If you have a compass blade attachment, you can easily cut a perfect circle, otherwise try to make it as even as possible.
Step 8: Extrude the Cutout
Put pressure on her. Satisfaction is almost the same as from popping a pimple.
Step 9: Positioning the Lens
Before gluing the lens, align it exactly with the hole.
Step 10: Glue the Lens
Step 11: Trim the Excess Cardboard from the Lid
After you put the lid on the box, it may cover part of the lens (this depends on the dimensions of the box). Take the cut out circle and use it as a template to draw and cut out the desired piece of the lid.
Step 12: Building a Smartphone Stand
Build a stand out of foam. Make sure it is perpendicular to its base, otherwise the picture will be distorted.
In this article, which continues our cycle of simple various crafts at home, we will tell you how to make a simple but adequately working projector at home. A homemade device that can be easily made at home even without special skills can replace a small home theater for watching movies or family photos.
Of course, the factory assembly wins in quality, but in terms of comfort and atmosphere, a homemade projector will be much better. Moreover, it can be done together with the child - this is a very serious plus for your relationship.
Even the child himself will not have any difficulties in assembling the projector from an ordinary box of cardboard and a banal magnifying glass if he decides to work on the device without the help of adults. This will take a maximum of 15 minutes.
Let's now tell you step by step how best to make such a projector with minimal time and effort. There are simple and complex schemes, we will analyze one that is as easy as possible in practical implementation.
Preparing to create a projector
To begin with, let's collect in front of us all those materials and components from which it will be possible to make our miracle projector itself.
We will definitely need an ordinary medium-sized shoe box, a 10X magnification lens, a stationery sharp knife, an ordinary marking pencil, black electrical tape, a paper clip and, of course, a smartphone. A homemade projector for viewing photos and videos will be ready very soon.
Carefully on one of the side walls of the box we cut out a hole exactly in the center in which the lens will be placed. It is very important that it is located strictly in the center - here a pencil will come in handy, with which we will draw diagonals on the side where we will cut the hole. It is in the center of the intersection of the diagonals that the lens will be placed.
We fix the lens with the help of a pre-stored electrical tape. However, other options for fixing are also suitable, for example, building glue or silicone.
Inside the box, we make a stand for placing a smartphone (if there is a special case that allows you to put a smartphone behind the lens, then no stand is simply needed).
We turn off the light, hang the curtains and start testing the projector. It will be necessary just by moving the smartphone to find the optimal location of it relative to the lens. It is necessary to achieve the highest quality image - everything is simple here and depends only on the position of the device and the box.
A properly working image flip application must be downloaded and installed on your phone. The fact is that when passing through the lens, the video or photo will automatically turn 180 degrees.
The best option for Android OS would be Ultimate Rotation Control, and owners of "apple" devices will be able to use Video Rotate & Flip or another option.
It is desirable to make a convenient input for the MicroUSB wire - phones are quickly discharged when playing videos or viewing photos.
As you can see, there is nothing complicated in making a simple home projector. The more pleasant moment will be that you will have to spend a minimum amount of money - after all, everything you need for it can be found in almost any apartment.
What points should be considered when working?
If you decide to make a really good projector, then you should increase all overall dimensions. Accordingly, use a tablet or laptop instead of a phone, and the box will also be larger, respectively. The manufacturing mechanics are exactly the same as in the small format.
IMPORTANT: If the image does not improve in any way, no matter how you move the device, then the problem is most likely the quality of the lens you have installed. It will be optimal if you find an old Soviet magnifying glass - their quality is simply amazing.
The brightness settings on your smartphone or tablet should be set to the highest possible. Painting the inside of the box black will also improve the quality of the projected image. Not every wall is suitable either - it would be best if the projection goes onto whatman paper placed on the wall evenly and at a right angle.
Be sure to organize viewing only at night and with minimal ambient light - only in such conditions the picture quality will be more or less normal.
Do not forget that this is homemade, not professional equipment - do not expect too much from it. Homemade projectors with a lens, without a magnifier, can also work fine.
We are sure that our ideas and detailed instructions for creating a home projector have become useful to you. Working with your child on such a device will help you establish additional contact with him, and cozy family evenings will be great activities to relax after a hard day at work. Make a projector and be sure that everything will work out for you.
DIY photo projectors
Have you ever imagined that you can make a home projector with your own hands from a simple shoebox, a touchscreen phone and a magnifying glass. Of course, you will not achieve a fair amount of clarity, but if you want to make a romantic evening for your beloved or try your hand as a young technician, this is just for you. And yet, let's find out with you how to make a projector out of a phone and a shoe box ?!
How to make a projector from your phone, what you need for this:
1)
Touch smartphone; 
2) shoe box;
3) Insulating tape or tape;
4) Magnifying glass or loupe;
5) Paperclips;
6) Stationery knife;
Homemade projector from the phone:
1) Shoe box in the middle should not be bright colors, if so, then paint the box inside with dark matte paint, or glue it with black paper. This is necessary in order to ensure good image quality.
3) When you cut a hole for the lens, it will need to be attached there. To do this, attach the lens to the hole and the joints, carefully glue it with adhesive tape (duct tape). The most important thing is to there were no gaps, so it is worth additionally checking the gluing points.
4) To mount the phone, we make fasteners from a paper clip. To do this, the paper clip must be unfolded, and then bent as in the picture.
5) If you studied physics at school, you should know that when an image passes through a lens, it will be inverted. Therefore, in the settings you need to flip the phone screen.
6) Since our projector missing focus ring, so we will focus it ourselves! To do this, we place the phone parallel to the wall of the box, then by moving back and forth we adjust the focus of the image. In this case, the room should be as dark as possible!
