Since the appearance on the market of household appliancesprojectors have changed a lot. These are not the expensive devices with no less expensive service, which could be used only in the dark. Today, the projector allows you to view photos and videos, it is easy to replace the TV or PC screen. And the price of models that support the resolution of Full HD, caught up with the cost of 40-inch television receivers. It's time to take advantage of this technology and become the proud owner of a home theater with a truly gigantic screen with a 300-inch diagonal, which is about 7.62 m.
Picture
Главным параметром выбора проектора является image quality. But how can this be done if the much-needed assessment of several models of an expensive machine fails due to the lack of a viewing room?
You can estimate the image quality of projectors by the following parameters:
- imaging technology;
- matrix size and resolution;
- contrast;
- brightness;
- focal length.
First of all, the image quality depends on the projection technology. Now three technologies are used: DLP, LCD and LCOS.
DLP
DLP (eng.Digital Light Processing) uses a tilt-changing micromirror array that directs light into focusing lenses. Coloring of a beam of light occurs in different ways. Some manufacturers use a fast-rotating three-color wheel. In this case, the eye sees alternating monochrome images, which may affect some people, and also creates a rainbow effect that interferes with viewing. Others use three matrices of micromirrors for each color separately (3DLP technology). Projectors using 3DLP technology are among the best, but also the most expensive projectors.
LCD
LCD technology (eng.The Liquid Crystal Display uses three liquid crystal arrays to form the red, green, and blue components of the video signal. The flow of light from a metal-halide lamp, passing through a prism or a sequence of dichroic filters that pass through one part of the spectrum and reflect the other, is divided into three components. Each is directed through its own LCD-matrix, which by changing the flow of light passing through each pixel, creates a monochrome image. The combination of the three components produces a multi-color projection. Among the disadvantages of this technology is called low image contrast (due to the fact that the crystal in the closed state transmits light, and the bandwidth of the matrix does not exceed 7%).
LCOS
LCOS (eng.Liquid Crystal on Silicon) is based on the previous two. But the light does not pass through the liquid crystal matrix, but is reflected by liquid crystals on the silicone. This results in high-quality images without the disadvantages of DLP and LCD technologies. In addition, it is possible to increase the pixel density and achieve high image resolution. But the price of LCOS-projectors is quite high, which so far limits their use by cinemas and large presentation halls.
LED
LED technology (eng.Light-Emitting Diode (LED) uses one of the above technologies to create an image with the difference that the light source here is an LED matrix. In this case, there is no need to replace the lamp, reducing energy consumption. Guaranteed service life of the LED matrix is 25 thousand hours. The disadvantage is the low luminous flux, not exceeding 2000 lumens.
The laser projector is equipped with a group of laserprimary color diodes. Less expensive are hybrid laser-led projectors, in which a blue diode laser, a green fluorescent element and red LEDs are combined to achieve high image brightness.
Resolution
Resolution is determined by the number of pixels.For high-quality images, these parameters of the video projector and the source must be the same. You can reproduce the signal with a different resolution, but the image will be distorted by compression algorithms.
Popular resolutions are 1280 x 768 WXGA, 1280 x 720 HD, 1920 x 1080 Full HD, 1920 x 1200 WUXGA.
Brightness
Luminous flux is measured in lumens.Projectors with a brightness of 2000-3000 lumens are used in classrooms and small conference rooms. A luminous flux of 3000-4500 lumens is suitable for large conference halls. The brightness of the image in this case is sufficient not to darken the room. Superbright projectors of more than 4,500 lumens are used at concerts, in nightclubs, churches, etc. The cheapest and smallest portable projectors with a luminous flux of less than 2,000 lumens require full or partial darkening of the room.
Contrast
Отношение наибольшей и наименьшей освещённости screen is called the contrast of the projector. For example, a contrast of 10,000: 1 means that the brightness of white is 10,000 times greater than the brightness of black. In a darkened room, the contrast is leveled by third-party light sources and is inferior in importance to the light flux of the projector.
Lens
Видеопроекторы могут оборудоваться объективами с the ability to manually or automatically change the focal length. This is necessary to resize the image without moving the projector itself.
Also, the lens is characterized by the ratio of the distance to the screen to its size. Projectors are long-focus (2–8: 1), standard (1-2) and short-focus (less than 1).
Features of LED-projectors
- Indoor use requires dimming for maximum clarity and image brightness.
- Devices with a luminous flux up to 300 lumens are designed for a screen width of 0.2 m, and more than 500 lumens - up to 3 m.
- Suitable for mobile home theater. Not a full replacement for projectors with metal halide lamps.
- Portability is achieved by the presence of an external power supply, wireless connectivity.
- Models with a high luminous flux have a high noise level, and therefore are suitable for use in public places.
- Power consumption is minimal.
LED projector: an overview of popular models
Every day on the market there are new models of projectors, the light source in which are the LEDs. Below are only those LED-projectors, the reviews of which were positive. So, let's begin.
ViewSonic PLED-W800 Mini LED Projector - Pocketthe device is designed for business presentations, as they say, "on the go." But, according to consumers, the power of the light flux allows it to be used at home.
Californian company ViewSonicspecializes in projection equipment since the late 80s. A few years ago, he became the pioneer of the new line of mini-LED-projectors with the model PLED-W500. W200, W600 and W800 models are now available.
The numbers in the model name correspond to the powerluminous flux in lumens. On paper, the comparison with the power of metal-halide lamps, which exceeds 2000 lumens, speaks not in favor of the LED projector, but in practice, judging by the customer reviews, the device illuminates the screen brighter than one would expect. The portable device is capable of conducting PowerPoint presentations, giving an 80-inch HD 1280 x 720 image at a distance of 2.5 m with a brightness that does not require darkening of the room. However, to watch movies, you will need to close the curtains and turn on Movie mode, which will give the image a more natural color. The compactness of the device required to sacrifice a change in focal length. But there is a mount for mounting on a tripod. If the projector is tilted relative to the screen, the image will be automatically corrected.
ViewSonic Pro9000 is a hybrid laser-LEDprojector that is perfect for home cinema. The beautiful colors provided by the DarkChip3 chip, the high definition of the Full HD image, 16,000 lumens of light output and the contrast of 100,000: 1 - this is what the consumer especially likes. The design of the projector does not use lamps and filters, which reduces the cost of operating the device almost to zero.
LG PH550, PW1000, PW1500 – LED-проекторы для houses presented in January 2016. Luminous flux in lumens and resolution (H for 1280 x 720 and W for 1280 x 800) are indicated in the device name. Model PH550 is equipped with a battery designed for 2.5 hours of battery life, Bluetooth-sound, wireless communication with the Android OS devices. In addition, the PW1000 is equipped with a digital TV tuner and is 3D-compatible, and its brightness tells about the merits of the PW1500.
Vivitek Qumi Q5 - portable mini-LED-projector with1600 x 1200 resolution, 500 lumens brightness and 3D support. The screen size is 30-90 inches (0.76-2.3 m) at a distance of 1-3 m. There is also a built-in player, 4 GB memory, USB port, wireless connection, Internet browser and battery. Users note the excellent color reproduction, contrast, image quality, design and compactness, but some are unhappy with the fan noise and insufficient volume of the device.
The Qumi line also includes projectors LED Q4, Q6,Q7 Lite, Q7 Plus. As the number increases, so does the brightness, which in the last model reaches 1000 lumens. The contrast is 30,000: 1, the resolution is 1280 x 800. The ability to control the projector using mobile devices running the Android OS or iOS is implemented. There is a trapezoid correction, lens shift in the horizontal and vertical direction, optical zoom.
Produces projectors Vivitek Qumi Taiwanese corporation Delta Electronics.
Optoma Products
Optoma offers the following LED technology projectors.
ML750e – компактный и лёгкий (менее 400 г) apparatus. This is a portable LED projector designed for gaming, watching movies and presentations without using a PC; There is a built-in memory and a slot for connecting a micro SD card. The resolution is 1280 x 800, the contrast is 15,000: 1, the screen size is 17-100 inches, the projection distance is 0.5-3.2 m. It consumes 65 W in work mode and 0.5 W in standby mode. Users are very satisfied with ultramobility and multi-functionality.
ML1500e is equipped with an integrated media player,document viewers, stereo sound, wireless connection and memory card. The resolution is 1280 x 800, the contrast is 20 000: 1, the screen size is 17-100 inches, the projection distance is 0.5-3 meters. It consumes 145 watts.
HD91 + - second LEDs usedgeneration, Full 3D 1080 p image, optical zoom. The contrast is 600,000: 1, the screen size is 30-300 inches, the projection distance is 1.5-19 m. It consumes 245 watts in bright mode and 150 watts in movie mode. No complaints from users.
Optoma Global Headquarters Corporationwhich are located in the USA, Europe and Asia, produces projection and audio devices for business, education and home use. Founded in 2002 in Shanghai, China.
BenQ projectors
BenQ company produces portable projectors LED GP30, GP3, GP20.
GP30 - short-focus (40-inch screen ondistance of 1 m) LED multimedia projector with a luminance flux of 900 lumens. According to the manufacturer, it is distinguished by the presence of stereo sound with SRS HD, support for wireless content transfer technology MHL and WiDi. Models GP3 and GP20 have brightness of 300 and 700 lumens, respectively. Resolution 1280 x 800, contrast 100 000: 1, tilt correction +/- 40 °. In 2014, the Taiwanese company BenQ became the world leader in sales of high-definition projectors, and the total number of models sold exceeded 1 million.
NEC NP-L102W - 1000-lumen LED projector with 1 GBinternal memory and an SD card slot of up to 32 GB, which will leave the laptop at home and hold presentations from a flash drive. The built-in office viewer allows you to open MS Office files and PDF documents. The design does not use rotating filters, which, according to reviews, reduces noise and eliminates the need to care for them. The resolution is 1280 x 800, the contrast is 10,000: 1. The Japanese company NEC Display Solutions, the manufacturer of this projector, has been operating for over 20 years.
Panasonic
In the professional projector Panasonic PT-RZ470UThe lamp has been replaced with a 3500 lumen LED-laser system. The resolution is 1920 x 1200, the contrast is 20 000: 1, the screen size is 40-300 inches, the distance to the screen is 2.6-10 m. The hybrid light source, according to user feedback, has a higher color purity, and the Digital Link system will transmit HDMI , uncompressed HD video, sound, and teams of Cat5 cable over a distance of up to 100 m. Panasonic was at the origin of the projector industry, starting their production in 1975. And it continues to occupy a leading position to this day, having a projector brightness record of 9000 lumens and the first to introduce wireless technologies into devices of this type. Users are very pleased with the overall image quality of the projector of a new type, but the level of contrast and color, they say, is still at an average level.
New from Casio
Японская компания Casio, которая первой начала to produce hybrid laser-led LED projectors, offers affordable models XJ-V110W, XJ-V10X, XJ-V110W, XJ-F210WN, XJ-F100W, XJ-F20XN, XJ-F10X, whose brightness reaches 3,500 lumens. The contrast of the new projectors is 20000: 1, tilt correction, wired or wireless connection to the network.
Acer
Acer also launches portable LED projectorsK137i, K138ST, K335 with a resolution of 1280 x 800 pixels and a luminous flux of 700, 800 and 1000 lumens, respectively. The contrast is 10,000: 1, the screen size is 17-100 / 25-100 / 30-100 inches, the distance to the screen is 0.6-3.2 / 0.4-1.7 / 0.9-3.0 m, tilt correction + / -40 °, support formats PDF, MS Office, power consumption 75/80/135 watts. Owner reviews are mostly positive.
Chinese lanterns
Нельзя здесь не упомянуть и о том, что рынок flooded cheap Chinese LED-projectors, reviews of which are extremely unpleasant. An example would be the Digital Galaxy DG-757 and Fugetek FG-637. According to consumers, at a declared brightness of 2,800 and 2,000 lumens, real turned out to be less than 140 and 90 lumens, respectively. This, as well as the enormous unevenness of brightness and sharpness, the technology of 20 years ago once again confirms the adage “the miser pays twice.”
