Multimedia projector is a miracle of 21st century technology, a very useful and multifunctional device. In an apartment, you can organize a full-fledged home theater, because the projection of the image allows you to view video on the screen in the entire wall. Using the projector for educational purposes makes it possible to broadcast video in a wide format for better assimilation of information by students. In the framework of this article, we will try to understand the principle of operation of various types of projectors, consider the technical characteristics of the devices, and also give recommendations on choosing a more practical model.
What is a multimedia projector?
A multimedia projector is a device that projects an image or video from an external source onto a large screen. The source can be removable media, a computer or other device that has an operating system. The development of technology has given additional functions to projectors. Now you can find models that synchronize with the storage media via a wireless Wi-Fi network. It is very convenient and practical.
Let's name the main characteristics of multimedia projectors. The undoubted advantage of these devices is the size of the projected screen. If we compare the device in terms of cost with a TV, the screen of which has a similar size, then the projector wins. The minimum price of a device intended for home use varies between 14,000-30,000 rubles.
Image quality depends largely on the specifications of the multimedia projector and screen properties. The canvas should have a high reflection coefficient, then the image will be clearer and sharper. To get a rich picture, you need to remove all extraneous light sources in the room.
Before viewing a recording from a removable media, you need to do some preparatory work. The projector is connected to the storage medium, to the sound system. The characteristics of the screen for the projector must meet certain requirements. Adjusts the sharpness of the image on the screen. Some models make extraneous sounds during operation, this creates inconvenience when watching a movie. The noise comes from the cooling system built into the projector.
The stationary projector is most often mounted on the ceiling. If the model is portable, then it is most convenient to place it on a cabinet or table. To start using the projector, you need to turn on the unit and correct the image by fitting it in the corners until the screen projection is properly rectangular.
Projector Classification
Currently, there are a huge number of projectors that differ significantly from each other not only in cost and functionality, but also in technical characteristics, manufacturing technologies for internal parts and profile purpose. Let's present a classification of types of projectors. By functional purpose, projectors are divided into 3 groups:
- Home cinema. These devices are intended for home use. The characteristics of home projectors of the budget line have the most basic functions. The devices are easy to use and are in the middle price range. The screen size can reach two meters diagonally. The projector has connectors for connecting to a personal computer, laptop or game console. In the absence of the necessary connectors, special adapters can be used to synchronize devices. These projector models also have a number of disadvantages: low brightness of the lamps, low level of clarity in budget models.
- Projectors for cinemas. These are professional powerful devices that project images on a widescreen cinema screen. These projectors are very expensive.
- Projectors for study and business. They are used in educational institutions and enterprises in order to convey information for review. The characteristics of school projectors differ in theiraffordable cost. Screen projection can reach 7 meters diagonally. Some models have a built-in speaker.
- 3D projectors.
Innovative devices that project a three-dimensional image. Such devices are used in the film industry, in educational institutions, as well as in museums and exhibitions.
Depending on the design of the modulator, the projectors are divided into:
- TFT projectors. The modulator is represented by a compact color LCD matrix manufactured using TFT technology. The distribution of light over the matrix is carried out by a condenser, which is a system of lenses.
- Polysilicone projectors. Three monochrome matrices (red, blue, green) are used to project the image. The optical system combines images from three matrices and a high-definition color picture is obtained. To distribute the light, special built-in mirrors are used, which direct the same amount of light to each of the three matrices.
- DMD projectors. Built on a reflective type system. The DMD-matrix consists of a large number of micromirrors, which can reflect the incoming light onto the lens or into the absorber. This forms an image on the screen.
The following types of devices are distinguished by the method of illumination of the modulator:
- Translucent type. The transmitted light flux is subjected to modulation, which leads to a strong heating of the matrix. For cooling, a fan is installed in the projector case,which makes noise during operation.
- Reflective type. The light flux is reflected and directed to the matrix. This does not cause much heat, which means that the installation of a serious cooling system is not needed.
Types of projectors and their specifications
The clarity of the picture and the drawing of the image largely depend on the resolution of the file being played from the media. In addition, the quality of the projected image depends on the specifications of the projector as well as the projection technology, lens specifications and resolution.
LCD technology
Light passes through the liquid crystal panel, which consists of a large number of pixels controlled by electrical signals. The pixels receive different amounts of voltage, which adjusts the level of transparency of an individual pixel, which means that the brightness of each point on the screen changes. This is how a complete projection image is formed.
This technology has significantly reduced the size of projectors and reduced their cost. The maximum light intensity at the same time began to reach 10,000 lm.
This technology has some downsides. The liquid crystal matrix begins to degrade and age over time. Wear will adversely affect image quality. Dead pixels may appear on the matrix. During operation, the device gets very hot, so a powerful fan is built into the case to cool it, which creates quite a loud noise. The bright and powerful lamps of such projectors have a highcost.
CRT technology
One of the first technologies for the manufacture of projection devices, which has been used for several decades. We list the main characteristics of multimedia projectors created using this technology. The basis of the projection principle is a cathode ray tube. Picture quality can be superior to other technology projectors. The black color is saturated, the contrast is good. The duration of continuous operation can reach 10,000 hours.
Viewing is possible only in a darkened room, since the maximum brightness level does not exceed 300 lm. The devices produced by this technology are distinguished by their massiveness and large dimensions. The device can weigh several tens of kilograms. And setting up the device is so complicated and lengthy that sometimes you need qualified help from a specialist.
The principle of operation of the projector is as follows: the signal is divided into components of three colors (red, blue, green), the intensity of the beam changes. Light passing through a magnetic field exposes the surface of the screen to a scan. A monochrome picture is created on the screen, the image of which is projected onto the screen. As a result, three projections are connected, and a color image is obtained.
D-ILA Technology
Devices produced using this technology are also equipped with LCD elements, but not translucent, as in LCD technology, but reflective. The light-modulating layer is located above the single-crystal silicon substrate. It is in it that the matrix control circuit is located. itgives a significant advantage over LCD matrices, since smaller matrices are capable of delivering higher resolution. There is no pixel grid on the projection of the picture.
The principle of operation is the same as that of LCD matrices: matrices create pictures of three colors and project the image through the lens onto the screen. The devices are small in size. Projection on wide screens is possible without loss of image quality. There are also negative sides: expensive lamps, the appearance of dead pixels, the lack of information about the service life of such devices due to the novelty of the technology.
DLP technology
The matrix is represented by a large number of small mirrors that can change their position. Each mirror can project light either onto a screen or into a light absorber. It turns out black and white colors on the projection. When the mirror changes its position with a high frequency, we get shades of gray. To separate other colors, a color wheel is used, which has light filters. It is because of the rotation of the disk that you can observe the "rainbow effect" on the screen. The color wheel in some models may have additional colors - yellow, cyan, magenta. There is also a transparent segment that plays the role of producing a pure white projection color.
The brightness of a black and white picture is especially important for devices that are used to demonstrate presentations or diagrams. On some models, increasing the brightness level of the light makes the picture dimmer.
Three-matrix projectors produced using this technology,work on the principle of overlaying three monochrome RBG images to obtain a full color image. Such devices have a high level of brightness, which can reach 18,000 lm. The winning features of this type of devices are as follows: small size, durability, low noise level, high brightness. Disadvantages include costly lamp replacement, possible dead pixels, "rainbow effect" in single-matrix models.
Laser projectors
One of the latest imaging technologies is laser. These devices are characterized by high cost, good performance and the highest level of projected image quality. Continuous operation of the laser can be carried out for 20,000 hours. Let's consider some characteristics of laser projectors. The brightness of 4500 lm will allow you to watch video even in a room that has additional light sources. Ultra-focus lenses of laser projectors allow you to place the device in close proximity to the projection screen.
The principle of operation of the device is similar to the previous ones. The laser forms three monochrome images that are superimposed on each other and blended. A system of mirrors takes part in creating a focused image. Laser projectors can project an image onto huge screens, while the image will be very rich and bright, and the color reproduction will be realistic. The screen surface does not have to be highly reflective.
Projector lamps
Light source to exerciseprojection is a lamp built into the projector body. Light output is measured in lumens. Currently, there are models that are capable of delivering 60,000 lumens. If we consider projectors of minimum power, it is worth noting that some budget devices have LED lamps that produce a luminous flux of hundreds or even tens of lumens.
In home viewing conditions, a projector with a luminous flux of 1000-1500 lm is sufficient. In the absence of other light sources, the quality of the projected image will be acceptable. Rooms with additional lighting will require more powerful projector lamps.
If the lamp in the projector is burnt out, it is better to replace it with the original one. But sometimes it is not possible to find an identical lamp, then you can use similar analogues, which are more affordable and available in stores. Let's look at some options and the main characteristics of projector lamps.
- Metal halide lamps. A variety of high pressure gas discharge lamps. The radiation of the light flux occurs due to the action of metal halides on mercury vapor. The light is very bright, and the lamp itself consumes a small amount of energy. The light becomes dimmer over time.
- Discharge lamps. They are built on the processes of the occurrence of an electric discharge in gases. Projector lamp specifications vary slightly depending on the materials used. High light output - up to 55 lm/W.
- Xenon lamps. Light emits a metal arc,located in a flask with xenon. The lamp produces a bright white light that is as close to daylight as possible.
- LED lamp. Used in budget projectors. Gives out a small level of light, only a few tens of lm.
- UHP lamps. The glow occurs due to the creation of an electrical discharge in mercury vapor. The lamp is small and produces a very bright light.
- P-VIP lamps. Variety of halogen lamps. High brightness and long service life.
Sony projectors. Models and Reviews
Sony's projector range has several dozen models.
SONY VPL-HW65ES
Projector designed for home use. We list the main characteristics of this multimedia projector. Maximum image quality - Full HD. Luminous flux - 1800 lm. The device is small and portable. The projection image is distinguished by its brightness and color saturation. Lamp life reaches 6000 hours. Manual lens adjustment will allow you to use the projector in different locations. Price: RUB 240,000-260,000
Positive feedback: handy device, small size, good picture quality, can be used in partially lit rooms.
Negative feedback: high cost, no glasses included.
SONY VPL-VW1000ES
The main features of the multimedia projector are as follows. The device is equipped with a heavy-duty lens that allows you to view the image in 4K resolution. Output brightness - 2000 lm. At home use, such a luminous flux will allow the device to produce rich and contrasting colors. You can view 3D movies with this unit. Price: RUB 1,000,000
Positive feedback: perfect image, small size of the device, no noise during operation.
Negative feedback: very high cost, more suitable for professional use.
SONY VPL-SW235
Thanks to 3LCD technology, the projected image has a high clarity and contrast ratio. The technical specifications of the projector are as follows: maximum resolution 1280800, luminous flux 3000 lm. There are 3 brightness modes. You can connect the projector via the USB port without the need to install additional drivers. There is a possibility of wireless synchronization. Price: RUB 63,000
Positive feedback: there is a remote control function from an iOS device via an app, good image quality, the ability to install the projector at a distance of 79 cm from the screen.
Negative feedback: high cost, only stationary installation of the device.
SONY VPL-SW630
Device type - widescreen three-matrix LCD projector. Maximum resolution 1280800, luminous flux 3100 lm. Designed for office or home use. There are VGA, HDMI connectors. Price: RUB 61,000
Positive feedback: good image quality in dark conditions, no noise.
Negative feedback: high cost, no wireless sync,short lamp life.
Epson projectors. Models and Reviews
EPSON EB-W42
Made by LCD technology, TFT matrix type, maximum resolution 1280800. Light flux 3200 lm, there is a built-in function of wireless connection via Wi-Fi network. The image has a sufficient level of clarity and contrast. Price: RUB 55,000
Positive feedback: relatively low cost, built-in speaker, good picture.
Negative feedback: short lamp life.
EPSON EB-X41
Projection technology - LCD, matrix type - TFT, color brightness - 3200lm. You can output images and videos from a removable USB storage device. To connect other types of media, there is an HDMI and VGA output. Price: RUB 34,000
Positive feedback: reasonable price, good brightness and contrast in a dark room.
Negative feedback: noisy operation, with partial lighting, the visibility of the screen deteriorates significantly.
EPSON EB-S05
Made with LCD technology. Maximum resolution 800600, luminous flux 3200 lm. Connects to storage media via VGA or HDMI connectors. There are built-in speakers. Mounting provides front projection, rear projection, ceiling mounting is possible. Price: RUB 24,000
Positive feedback: good image quality, relatively low price, remote control included.
Negative feedback: high fan noise, poor picture quality when availableadditional light sources.
EPSON EB-X05
Projection technology - LCD. The maximum resolution is 1024768, the luminous flux is 3300 lm. Wired connection via VGA and HDMI ports. There are built-in speakers and a remote control is included. Price: RUB 26,000
Positive feedback: the ability to project an image up to 300 inches, good video quality in the absence of extraneous light sources, relatively low price.
Negative feedback: high noise level, loss of image quality with additional light.
LG projectors. Models and Reviews
LG PH30JG
The device itself is very tiny, its weight is 0.49 kg. The main characteristics of the projector are as follows: the maximum video resolution is 1280720, the light brightness is 720 lm. Wireless connection via Wi-Fi is available. It is possible to connect a USB storage device. Price: RUB 40,000
Positive feedback: good image quality; built-in battery, designed for 4 hours of work; the ability to connect speakers via Bluetooth.
Negative feedback: no HDMI and VGA connectors.
LG HF85JS
Ultra short throw high performance laser projector. Short throw projector specifications are as follows. The maximum resolution is Full HD, the luminous flux is 1500 lm. The device has the function of wireless synchronization with the storage medium. Can project an image from a distance of 12cm. Price: 130,000 RUB
Positive feedback: veryclear and contrasting projection pattern, small dimensions of the device, quiet operation, wireless connection.
Negative feedback: high cost.
LG PH450UG
DLP matrix technology. Maximum resolution 1280720, luminous flux 450 lm. There is a 3D function, a remote control is included. There are built-in speakers. Wireless synchronization via Bluetooth or Wi-Fi is possible. Price: RUB 45,000
Positive feedback: good picture quality, wireless connection.
Negative feedback: relatively high cost, built-in speakers are very quiet.
Acer projectors. Models and Reviews
Acer X118
DLP projector. Maximum resolution 800600, luminous flux 3600 lm. There is a VGA input for connecting the machine to a computer. It is recommended to use the machine in an office or school. Price: RUB 19,000
Positive feedback: low cost.
Negative feedback: can only be used in a dark room, short lamp life, grainy image.
Acer H6517ABD
DLP large format projector. The color wheel is six-segmented. Maximum Full HD resolution, luminous flux 3400 lm. Ports for connecting media - VGA, HDMI. The device belongs to the category of office equipment.
Positive feedback: low cost, there is a power saving mode.
Negative feedback: Poor video image quality, poor projection quality whenextraneous light, extraneous noise.
Acer C120
DLP matrix technology. Maximum resolution 845480, luminous flux 100 lm. The device gives an image with a diagonal of up to 2.5 m. The connection is via a USB port. Weight - 180 g. Price: 16,000 rubles.
Greetings: Very small and light portable, great for presentations.
Negative feedback: no HDMI and VGA connectors, poor video playback quality even in a dark room.
Acer H7850
DLP matrix manufacturing technology. Maximum resolution 38402160, luminous flux 3000 lm. Connection is via HDMI, VGA, USB ports. The device has 2 speakers. Price: RUB 125,000
Positive feedback: high quality resolution and color reproduction, it is possible to use both portable and stationary.
Negative feedback: high cost for this functionality, no wireless sync, no 3D function, short lamp life. High image quality requires a higher screen specification for the projector.
How to choose a projector
When choosing a projector, the buyer always doubts which model should be preferred. In order to make the right choice, you need to understand the main characteristics of the projectors. Let's take a closer look at how to choose the right device and select the necessary functionality.
The reason for doubt in the choice lies in the lack of awareness and knowledge about those orother technological features of devices. Consider the options for projectors that are best suited for specific purposes.
If you are looking for a projector exclusively for home use, then choose a model of a well-known brand, and not a Chinese counterpart, which will have a lower cost. In addition to the cost, you should pay attention to such parameters as:
- Max resolution. If you are not going to project an image on a very wide surface, then 800600 quality will be enough for you, it is better to take models that produce HD or Full HD quality.
- Luminous flux. The allowable range for the home version is 1000-2000 lm. In this case, a small illumination of the room in which the image is projected can be allowed. The power of the projector is a characteristic that is one of the most important performance indicators.
- Projection lamp type. Some lamps can last up to 30,000 hours. If you plan to use the projector frequently, then the quality of the lamp will be an important factor.
- Noise level. There are projectors whose fan is so loud that it interferes with the perception of the film itself. The volume of the device is indicated in the technical specifications, it is measured in decibels.
- Color rendition. The color scheme should be natural and realistic.
- Contrast limit. Choose a machine with a contrast ratio of 1000:1 or 2000:1. If this setting is lower, then darkened images will be difficult to distinguish.
- Connection methods. Somemodels do not have running slots for connecting an information source, since synchronization occurs exclusively wirelessly via Wi-Fi.
Taking into account all the nuances, you can choose the perfect device for your needs. When you decide on the desired parameters, it becomes clear how to select the characteristics of the projector.
In conclusion
The wide variety of projector options available on the domestic market is overpriced. If you have read the article to the end, then you should understand what characteristics you should pay attention to when choosing a projector.
