In the modern world, any training, negotiations at work and even school lessons are not complete without appropriate presentations. And no wonder, because with the help of images people absorb information faster and better. To present a product, document, report or any picture on the screen to others, it is enough to use a computer, TV or a special device for viewing illustrations. We will talk about the name of the device for viewing slides, as well as the types of these devices.
What is this?
If someone still hasn't remembered the name of the slide show device, it's a projector. Such devices allow you to receive images on a remote screen using the method of geometric projection.
These devices have appeared on the electronics market for a very long time, but only a few years ago they became not an expensive “pleasure” for the rich, but a common technique that is indispensable during presentations at work or in educational institutions. At the price of devices for viewing slides are now almost identical to widescreenTVs, so any consumer or company can afford to buy one.
Types of projectors by size
First of all, they decided to classify these devices according to their dimensions. Depending on this parameter, they are:
- Stationary, which are the largest, most expensive, but functional devices. Such projectors are installed in a strictly designated place, such as DVD players and similar devices. They are often used by both large companies and ordinary users at home. In stationary devices for viewing slides, in addition to high functionality, there are other features. For example, various modern interfaces, intelligent control capabilities, etc.
- Portable, which, unlike the previous version, can be moved from place to place, which is especially important, for example, for educational presentations. Although they are compact, they are almost as good as stationary devices in terms of quality, characteristics and functionality.
- Pocket, which is perfect for users who spend all their time on the move. Such devices can be carried with you wherever and however you like, because on average the mass of such devices is only 200-300 g.
- Ultraportable projectors. They are more compact than pocket devices, but less functional. Suitable only as an additional device for creating simple presentations.
Types of projectors byresolution
Each slide viewer is also classified according to other criteria. For example, by resolution, that is, by the value that determines the number of dots (pixels) per unit area (inch). Depending on this parameter, there are:
- Regular projectors: SVGA (800 x 600), XGA (1024 x 768) and SXGA+ (1400 x 1050), 4:3 aspect ratio.
- Wide projectors: WXGA (1280 x 768, 5:3), WUXGA (1920 x 1200, 8:5), HD 720p (1280 x 720) and Full HD 1080p (1980 x 1080). The latter are the most common formats in the modern electronics market. The aspect ratio of both projectors is standard - it is 16:9.
But when choosing, you need to pay attention not only to the resolution of the device for viewing slides. The types of screens of these devices also play an important role. Everyone can reproduce a picture differently, even despite a decent format. Therefore, to get really good quality slides, you need to start from the ratio of resolution and screen sizes combined.
Types of projectors by their functionality
Today, there are both old and new devices on the technology market. Of course, new items have rich functionality, while past models can no longer surprise the modern user. Therefore, in order not to make a mistake with the choice of device, there is this classification:
- overhead scopes;
- slide projectors;
- bishops;
- multimedia devices.
Codoscopes
Often such devices are called graphic projectors. The principle of their operation is quite simple: the projected original (drawing, diagram, picture drawn on a special transparent film) is superimposed on the condenser, and due to a vertically located lens and a mirror set at an angle, the light changes position to a horizontal one, hitting the screen, which can be an ordinary wall or a white chalkboard.
Now such devices for viewing slides are not produced and are practically not used, as they have many shortcomings. For example, PCs and laptops cannot be connected to them, and creating pictures for presentations takes too long.
Popular models: "Lector-2000", "Peleng-2400", "Liter-1400".
Slide projectors
Still similar devices are called overhead projectors. In fact, these are improved analogues of codoscopes. They are also designed to view only still pictures drawn on transparencies. The only advantage of such devices over overhead projectors is ease of use. If in the previous version it was necessary to manually superimpose pictures on the condenser (some of them also draw on their own), then overhead projectors, for example, carousels, saved users from such torment. In such devices, special "shops" are used, where up to fifty can be placed at a time.small format slides within.
Unfortunately, such devices are now rarely used to create presentations. Their main and only drawback is the inability to connect to a PC or laptop.
Popular models: "Diana-207", "Alfa-35-50", "Spark", "Lector-600", "Peleng-600", "Light", etc.
Bishops
If you need to project an opaque object (a photocopy of a book page, a drawing on paper, etc.), then this machine is perfect for viewing slides. Features of the episcope also lie in the fact that it does not need to be prepared for work. It is easy to use and shows a fairly high-quality image. And anything can serve as a presentation material: from a book to a sketch on a notebook page.
Modern devices
And finally, the most common device for viewing slides is a multimedia projector. Depending on the technologies on the basis of which the device was created, they distinguish:
- DLP projectors that create an image thanks to a matrix and several mirrors, each of which rotates under the influence of specific signals. Such devices show pictures of very high quality with deep detail, which is why they are much more expensive than their counterparts.
- LCoS-projectors that are not inferior in performance to devices with DLP-matrix and even slightly better than LCD-devices. Judging by user reviews, such devices showa fairly clear picture, without blur and "grid" effect.
- LCD projectors that are almost out of production. They work using a matrix of red, blue, green colors and light coming from a lamp. User reviews about this product are quite contradictory. Some note that for a small price, LCD projectors work stably and show a relatively high-quality image. Others say that the pictures of most models are obtained with a "grid" effect.
- CRT-projectors (CRT) are reliable, functional stationary devices with high image quality. The only disadvantages of such devices are the complexity of installation, high weight and high cost in the market.
Popular multimedia projectors: Acer X117H, Benq MS, Epson EB, Tecro PJ, Vivitek DW, Asus S1, etc.
