Nowadays we mostly meet with pico projectors, as part of a device – tablet, smartphone, docking station. Meanwhile, for quite some time now they have become a separate class of independent devices, with their characteristics, features, and scope of application.
In this article, we will try to figure out where the mini projector came from, how it is arranged, where these projectors are in demand, and also give a couple of practical tips on their choice. Also, visiting the link below you’ll find a 50% off discount on the LumiHD mini projector, one of the trendiest and best selling projector of 2017.
The principle of operation and the appearance of these projectors
So, we are convinced that the pico-projector in the future (if we are talking about a separate device) will be considered a miniature projector, placed in the pocket, that is, with the dimensions of a maximum of 100x100x50 mm. We are sure, most associate projectors will certainly not be with such dimensions, but in addition – with a powerful LED lamp and noise of the cooling system. The sounded miniaturization imposes certain limitations, both on the existing imaging technologies, and on the “final” characteristics – brightness, contrast, color reproduction, resolution, power consumption and so on. Still, the market now offers some small-sized projectors with innovative technologies that offer new opportunities. If you’re interested in browsing some of these projectors, you should check out the mini 1080p projector by the company MyMobile Gear.
Before talking about the principles of the action of modern projectors, it is worth to say a few words about the previous technologies for obtaining the projected image. We will not go deep into depth, we will focus only on the three most common in the recent past: LCD, LCOS, and DLP technologies.
In projectors working on LCD (Liquid Crystal Display) technology, the image is formed on the LCD matrix, which is visible through a powerful lamp. Controlling each pixel of the matrix, you can change its transparency and, accordingly, receive a change in the monochrome image on the projection screen. Add light filters that divide the stream of light into red, blue and green, three LCD matrices instead of one (for each stream), an optical information system and get a color image. The disadvantages at first were lacking (insufficient speed, low contrast or network structure of the image due to opaque areas on which each cell has control elements), but with the development of technology, they were leveled. A significant disadvantage is only one – the matrix in the projector due to work on the lumen requires a significant heat dissipation, hence the need for a high-quality cooling system, larger dimensions and so on.
Nevertheless, the method of obtaining the projected image by controlling the cells of the LCD matrix is still promising. It is enough, for example, to control each pixel electrodes on the matrix to be reflective and to place them not in the side, but under the pixels. This matrix does not work on the lumen, but on reflection – the technology is called LCoS (Liquid Crystal on Silicon). The image is more contrast, homogeneous, without a mesh structure, and the matrices themselves have a higher resolution and efficient use of the area. There is also a minus – the matrices of the road in production, and as a result, the technology is still not widely used.
The third, the most famous, technology for obtaining a projected image DLP (Digital Light Processing) also works on reflection. The image on the projection screen is formed by directing the light to a special DMD (Digital Micro Device) chip, consisting of a large number of micromirrors controlled mechanically. Each micromirror can be in two positions, respectively reflecting the light flux into the optical system of the lens or to the light absorber, – on the screen a light or dark point of the image is formed. The brightness is determined by the time of finding the micromirror in one of two states, the colors can be formed in two ways: rapidly alternating superimpositions of blue, green and red frames from one matrix of micro-mirrors or the output of an immediately full-color stream by adding currents from three matrices at once. DMD chips are difficult to manufacture (by the way, only Texas Instruments manufactures them), but they are durable and have a denser layout of the elements participating in the image formation than the LCD matrix, which immediately affects the quality of the picture.
After a tour of the technology of obtaining the projected image should become more understandable, as it became possible the appearance of pocket projectors. The desire to minimize the dimensions led to the abandonment of a volumetric high-power lamp, therefore, cumbersome cooling and power systems were not needed. The lamp was replaced with high-speed semiconductor light-emitting diodes, lasers or even their combinations.
As a consequence of reducing power consumption, it was possible to power the device from the USB port, and also equip it with an internal battery.
The basic light-modulating elements – LCD matrices and DMD chips have also decreased.
The imaging technologies were slightly renamed due to many reasons (FLCoS, DLP Pico, PicoP (based on lasers)), but the essence remained the same.
However, not without a spoonful of tar. It was necessary to significantly sacrifice the light flux – if in the same home projectors this parameter averages more than 2000 lm, then in pico-projectors it hardly reaches 100 lm. In addition, do not spoil the projectors and resolution: feel the difference between 1280×800 or 1920×1080 for full-sized projectors and 854×480 for “pocket” (but there are no rules without exceptions – in 2015, the Sony MPCL1 pico projector was announced, which, using PicoP technology, Capable of displaying an image resolution of 1920×720).
History and classification
The term “pico-projector” itself arose as a result of banal marketing competitions. So, in 2006, after several years of development, the Israeli company Explay launched a projector that fits into a regular pocket – several inches long and a mass commensurate with a mobile phone. At that time, it was the most miniature projector in the world, which naturally reflected on its name – the Explay Nano Projector. Two years later, there were direct competitors, one of which had the name – PK-101 PICO by the Taiwanese company Optoma and it sounded the same “Pico”.
Nowadays the phrase “pico projector” has become a household name and is used abroad for all similar projectors of this type. Along with this label in the search, you can find their other names such as “pocket”, “ultra-portable”, “portable” projector.
And yet these projectors have their niche, and moreover, it is growing rapidly. Their “fault” is their mobility. The organization of express presentations, use on business trips, on vacation, even on the road – there can always be a situation where you can see something on the big screen more conveniently than on a smartphone, tablet, laptop.
However, the most interesting are not portable projectors in the form of separate devices, but their integration into other mobile devices:
– docking stations;
– media players;
In pico-projectors in the form of separate devices install the Android OS with all the “consequences”, they connect to the Internet, create interactive interfaces on their basis and so on. In general, perhaps the day is near, when it will be possible to rethink not only the concept of “display”, but also the “touchscreen”. And how do you get the idea to connect such a mobile projector with the camera in the oven and display the image of the food being prepared for restaurant visitors?
Actually, there are no complicated rules for choosing a pico-projector as a separate device – first of all it is necessary to pay attention to such characteristics as the luminous flux in lumens (lumens), contrast and resolution.
The maximum number of supported sources and interfaces (built-in memory, memory card, USB flash, HDMI, Wi-Fi, audio in / out, etc.), more capacious battery, the built-in sound is welcomed. It is not superfluous to have a mount to the tripod and remote control.
According to the technology of image acquisition in 90% of cases, it will be DLP, although LCoS is also found. Such characteristics as the minimum and maximum image sizes diagonally (from 10 to 150 inches respectively) are less significant, it is more worth paying attention to the minimum and maximum projection distance (usually from 0.2 m to 6 m, respectively).
Recommendations for the operation of projectors
Buy the lamps in advance!
The lamps for your projector are its heart and the main consumable. Since projectors use gas-discharge lamps, they cannot last forever. Despite the fact that the life of such lamps is estimated in thousands of hours, sooner or later there will come a time when it will have to be changed. Take care that this moment does not come in the middle of an important presentation.
Turn off the projector properly!
Any projector is equipped with a cooling system that protects the lamp from overheating. The cooling system continues to work even after the projector is turned off, until the heated lamp has cooled to a safe temperature. Therefore, in any case, you cannot disconnect the projector from the power supply to a complete stop of the cooling system! This can lead to the failure of the lamp.
Use the UPS!
Since the standard lamp for the projector is not very expensive, a sudden failure of it can be a very unpleasant event. Minimal suspension of the cooling system can be fatal, so any projector is afraid of a sudden power outage. It is highly recommended to connect the projectors to the mains through an uninterruptible power supply (UPS). Even in the most powerful projector, the cooling system does not consume a lot of power, and any UPS can handle it in a working condition. If there is a power outage during the projector’s operation, it is recommended to turn it off immediately, leaving only the cooling system to work, since the power of the UPS may not be enough to support the power of the entire projector.
Basic rules of operation of projectors
The latest models of Sony projectors, of course, are capable of doing wonders. They allow you to get a high-quality image in such conditions, which previously seemed simply unthinkable when working with such a device. But, nevertheless, like any equipment, modern projectors require certain conditions to be met during their operation.
Many manufacturers of complex types of projection technology recommend not to install them on your own, but use the services of specialists. It is also recommended to always check the conformity of the operating voltage to which the projector is designed to the voltage in the mains. If the device is not used daily, its plug must be disconnected from the outlet.
It is better if the power outlet is near the projector and easy access is always available. When the projector lamp is on, you cannot look into its lens. Make sure that children do not bring their hands or face to the ventilation holes of the projector, because of the hot air coming out of them.
When you need to adjust the height of the projected image when working with the projector, try not to pinch your fingers with the tilt controls. When this knob is pulled out, do not force the projector from above.
The best image from most projectors can be obtained by avoiding direct light from artificial or natural sources on the projection screen. Ceiling sources of local lighting are quite suitable for working with the projector, the best option is a room with fluorescent lamps in the housings.
To install the projector, a room with a floor and walls covered with non-reflective materials is most suitable. Many models of medium-sized projectors and the cheapest models require you not to turn them off from the outlet while the fan is running.
Manufacturers warn that it is impossible to obstruct the ventilation openings of projectors and place in the immediate vicinity of them any objects. If these conditions are not met, the temperature will rise inside the projector, the image will deteriorate, and with constant exposure to hot air, the device will fail.
In order for the projector to look good for many years, its case needs to be wiped with a soft cloth. The stubborn stains are removed with a cloth moistened with a solution of a mild detergent, but not with a paint thinner, benzine or an abrasive detergent. Do not touch your lens with your bare hands. Dust from it is removed with a soft dry cloth. Do not touch the lens with a damp cloth, cleaning solutions and solvent.
When mounting the projector on the ceiling, make sure that it does not get cold and warm air from the air conditioner. It is also not recommended to place the projector near any heat sensors and smoke detectors.