Ultra short throw, short throw and long throw projectors are the three main categories into which multimedia devices can be broken down. Their main difference from each other is the size of the distance between the projector and the image plane. Each type of device has its niche and scope. Long throw projectors are a classic, they appeared first, have a simpler technological solution and are used today mainly in large halls and cinemas. Short-throw devices are used more often in offices, at presentations, and finally, ultra-short-throw devices, which will be discussed in this article, are convenient in apartments or in small educational or office spaces.
Ultra short throw projectors: types, benefits, scope
What are ultra- and short-throw projectors good for?
- Located close to the screen, which eliminates long cables and simplifies the installation (installation) of the projector.
- Allows you to achievewidescreen picture in a small room (theatre effect).
- During the demonstration of the image, the light flux from the projector does not blind the audience and the speaker, there are no shadows from the teacher or those sitting in the hall on the screen.
The difference between an ultra short throw projector and a short throw projector is in the projection ratio. Throw ratio (or throw ratio) is the ratio of the distance between the screen and the projector to the screen width. If for a short-focus one its value is 0.5-1.5, then for the second one it is less than 0.5, which allows you to get an image size diagonally up to two meters from a distance of less than half a meter.
Reviews of teachers, speakers on the operation of these projectors are enthusiastic, since the installation process of the projector has been simplified, special technical skills or invited installation specialists are not required, and lectures and reports have become much more convenient and efficient.
Lens-mirror
Ultra short throw projectors, in turn, are divided into two types: lens and lens-mirror. Lens-mirror is a new word in the development of projection technology. They are equipped with a special optical system consisting of a lens and a mirror. The light flux from the lens is directed not directly at the screen, but at the mirror, and from there the reflected image hits the screen. Thus, it is possible to reduce the projection distance to tens of centimeters. Classic lens models have less mass, but work from a greater distance to the screen. Installing such projectors is easier, since, as a rule, they already come with a mounting bar and are mounted on the same wall as the screen. Also a plus, as there are often problems with mounting the projector to the ceiling in high rooms.
Features of operation of lens-mirror projectors
It should be noted that the use of ultra-short throw projectors places high demands on the surface of the screen. Since the light flux falls on the reflective surface at an acute angle, the unevenness and roughness of the screen create shadows and glare, which affects the image quality. Therefore, it is necessary to use screens with a white or matte smooth surface. We must pay tribute to the developers of ultra-short-throw projectors, they had to deal with uneven screen illumination (due to the acute angle of incidence of the light flux, the edges of the screen farthest from the lens were illuminated with less brightness). I had to apply non-standard software and hardware solutions, up to the use of free-form objective lenses, calculated according to complex programs. With the advent of projectors with such a small projection ratio, the scope of their application has expanded, including for advertising purposes. For example, in shops and markets, advertising of services and goods has become possible in conditions of limited space.
Ultra short throw laser projectors
Laser projectors are a new branch in the development of projection technology. Unlike classical ones, the light source in them is a laser emitter, and not a mercury lamp orLight-emitting diode. The advantage of this technology is the absence of any requirements for the reflection surface, no loss of clarity, no defocusing even on an uneven surface. The principle of obtaining an image is similar to the method of obtaining an image in old cathode ray tubes. The laser beam scans the surface 50 times per second and forms an image as a whole.
Advantages and prospects of the laser projector
Advantages of laser projector:
- long service life of the laser source up to 20,000 hours versus 3000-5000 for the lamp;
- Consumes little power and runs quietly as no cooling is required;
- does not require time to warm up and cool down, instantly turns on and reaches maximum brightness and also, at the moment, turns off;
- can create images on huge screens of several tens of meters;
- high contrast ratio, produces perfect blacks, not possible with lamp projectors;
- since there is no lens in it, from 30-40 centimeters it can produce a large image up to two meters.
Disadvantages of laser projector:
- so far very high cost;
- heavier than lamp projectors.
According to experts, the future belongs to laser projectors, because due to technological advantages it is possible to increase the brightness of the light flux and the clarity of image detail indefinitely.
Interactive projectors increase learning efficiency
Ultra short throw interactive projectors make learning extremely convenient, interesting and productive. The interactive capabilities of devices today are ubiquitous in life - first of all, our smartphones, screens in cars, payment terminals, etc. Of course, projector manufacturers could not help but give them interactive capabilities. The first to appear were ultra-short-throw projector kits with a whiteboard. The kit consists of the projector itself, mounts, an interactive whiteboard that determines the coordinates of the touch to the surface, and software that controls interactive functions. The device transmits the image from the computer to the board, which, using built-in sensors, transmits the location of the stylus or finger back to the computer. Boards differ in size and types of sensors, their price depends on this. Optimal in terms of "price / quality" are optical boards measuring 2.08 meters.
Interactive short throw projectors are a more modern and perfect solution. They already have built-in interactive features. The projector's built-in infrared makes any surface interactive, eliminating the need for an interactive whiteboard.
According to the feedback of teachers, the interactive learning process is extremely convenient for both the teacher and the student. Everything is clear, a lecture or lesson gets into students' notebooks along with the notes made in the lesson.
LED projectors: advantages and disadvantages
The main difference between the ultra-short-throw LED projector and others is that the light source in it is not an ordinary lamp, but LEDs. LEDs emit light, and a DLP micromirror matrix forms an image. Since the matrix and LEDs are miniature, the device is compact and lightweight.
Advantages of Ultra Short Throw LED Projector:
- light weight and size. There are low-power projectors the size of a pack of cigarettes;
- low energy consumption, as LEDs consume 7-8 times less energy than lamps;
- Long life LED, 5-10 times longer than bulbs.
There is one and very important drawback - a low luminous flux of no more than 2000 lumens, which implies its use only in dark rooms.
For home use, such a projector is quite suitable, but for business trips, due to its small size and light weight, its use is very tempting.
Epson projectors are leaders in the global multimedia industry
Epson ultra short throw projectors are part of a large line of projectors from this Japanese corporation. Seiko Epson was the first company in the world to release the device in 1989. Since 2001, she has been the undisputed leader in this industry. It has the widest range of projectors among competitors for any task and different price categories. Epson ultra short throw projectors in education are used to create interactive classrooms in higher and secondary educational institutions. And in this segment, Epson is a trendsetter and leaderinnovation.
Modern line of Epson ultra short throw projectors includes the following models: Epson EB-595Wi, EB-675W, EB-675Wi, EB-680W, EB-680Wi, EB-696Ui and others. Since these projectors are used in education, i.e., as a rule, in bright rooms, one of the requirements is the brightness of the light flux. All models shown are very powerful: 3200-3500 lumens.
Epson EB-595Wi junior model has the following main features:
- very short projection distance (44 cm) on the screen - 190 cm;
- high contrast - 14,000:1;
- luminous flux - 3200 lumens;
- very high lamp life of 10,000 hours;
- resolution WXGA (1280x800);
- interactive image on any surface.
By marking the model, you can find out some of its characteristics. For example, the letter i indicates that this model is interactive, the letter W is the resolution of WXGA (1280x800), U - WUXGA (1920x1200).
LG projectors are the best in gaming and home models
LG needs no introduction. Among all the variety of equipment offered by the company on the world market, LG's ultra-short throw projectors stand out. The company is not a world leader in the production of these devices, like Epson Corporation. But it has taken the lead in the home and gaming segment, as well as in the LED projector market. One of the new products in this segment is the ultra short throw projector LG PH450UG-GL.
The amazing model has the following characteristics:
- from a distance of 33 cm, an image of 2 meters is formed;
- wireless connection - video is transmitted via Wi-Fi, sound - via Bluetooth, 2.5 hours battery life;
- weight - 1, 1 kg;
- brightness - 450 lumens.
Full HD is the required image quality standard for a projector
Projectors used at home as home theaters must display high-quality content, and that will be Full HD with a resolution of 1920x1080 pixels in the coming years. As a result, Ultra Short Throw Full HD projectors have begun to hit the market, although the price is still high. Among the released models are the following projectors - the above mentioned in the article LG PH450UG-GL, LG PH1000U, Optoma EH319UST, Optoma EH320UST, Epson EH-LS100, etc. The listed models are different in price, characteristics, image acquisition method. LG are the cheapest LED projectors, they are low power, inexpensive (a little over 40,000 rubles), but at home, where you can reduce the illumination of the room, they will suit the audience quite well. Optoma middle price category, lamp, powerful enough 3000 lm, price - 120,000-150,000 rubles. And finally Epson - the most expensive model - 250,000 rubles, laser, very powerful, with a brightness of 4000 lm. All presented projectors, especially the last one, are a real alternative to huge TVs, and, according to experts and users, such devices are the future.
