With the departure of leading distributors from Russia, we have lost most of the films that are shown in cinemas around the world. But who said that you can’t organize a cinema hall at home and watch new digital releases on the big screen? First of all, you need a projector for this. We figure out what types they are and how to choose the right one for your requirements.
Table of Contents
For a long time, lamp-based projectors were the only option available to most people. The lamps used in them are flasks with two electrodes and gas. When an arc discharge is formed between the electrodes, the gas begins to glow.
The most popular projection lamps are UHP (Ultra High Pressure) filled with mercury vapor. Their advantages are high brightness, compact size and low cost. The main disadvantage is the short service life (only about 3-4 thousand hours), after which the lamp will need to be replaced.
More advanced are xenon lamps. They offer maximum brightness and uniformity, high contrast and a pure color spectrum. The price of such elements is much higher than that of UHP, and the service life is shorter. So projectors with xenon lamps are mainly used in cinemas.
Now projection lamps are becoming a thing of the past, and LEDs and lasers are taking their place. Such elements are the most durable and provide at least 20,000 hours of operation. In addition, projectors based on them are quieter and more compact than lamp counterparts, since the light sources themselves heat up less and take up little space.
LED models use red, green and blue diodes. This achieves natural color reproduction, but the image brightness is low compared to laser models.
Laser projectors are often equipped with a rotating color wheel. This is a fast spinning disc with red, green and blue color filters. The light from the laser passes through the color filters in such a way that the image is divided into three frames with primary colors.
These frames are sequentially projected onto the screen. A full-color image is already formed in our brain – we do not see separate red, green and blue frames, but perceive them as an overlay of one on top of the other.
Because of the color wheel, a rainbow effect appears, expressed in color halos around objects. There are also projectors with three laser sources (red, green and blue) – they are devoid of a color wheel and, as a result, a rainbow effect. Another advantage of the “three lasers” is high brightness (the color wheel reduces it by almost half) and a wide color gamut, reaching 100% of the BT.2020 space. This is the best indicator in the industry. The disadvantage is the high price.
There are two principles of projection: diaprojection and epiprojection. In the first, light passes through a transparent element with an image, such as a film. In the second, light is reflected off the image and projected onto the screen using optics. Different types of digital projectors use either the first or the second principle.
The most common type of projector is DLP (Digital Light Processing). In it, the light from the source passes through the color wheel and is reflected from a matrix consisting of movable mirrors, after which it is projected onto the screen. That is, the principle of epiprojection is used.
Each mirror on the matrix is responsible for a separate pixel. In the upright position, the mirror reflects light, forming a white pixel. In rejected – blocks the light flow, so that the pixel becomes black. Deviating to the desired position, together the mirrors form a projection of the image on the screen.
The advantages of DLP technology are high contrast, low response time and reliability. Disadvantages – not the highest brightness, as well as the rainbow effect in models with a color wheel.
Another type of projector is liquid crystal (3LCD). In it, the light is divided into three streams, each of which passes through the LCD matrix. The latter works as a color filter, passing only the required spectrum (red, green or blue).
Next, three streams with primary colors are collected by a prism and projected onto a screen, giving a full-color image. It turns out that 3LCD projectors work on the principle of overhead projection.
Models with this technology do not need a color wheel, so they do not suffer from the rainbow effect. Also, the image is brighter and more saturated than DLP-analogues.
3LCD projectors also have disadvantages. If you do not consider the top segment, they have a lower level of contrast compared to DLP. This is due to the fact that LCD matrices are not able to completely block the light from the source, which is why it is impossible to get a completely black color. They also have a higher response time, which makes jerky movements blurry. Finally, such models are more bulky, noisy and vulnerable to dust.
The most advanced projection technology is LCoS (Liquid Crystal on Silicon). In a sense, this is a hybrid of DLP and 3LCD – this type of projector uses LCD matrices with a reflective substrate.
Light passes through the matrix twice, reflecting from the substrate. This provides a higher level of contrast than 3LCD. LCoS projectors have two disadvantages – weight and price. Models from JVC and Sony will cost $5,000 or more.
A few years ago, 4K projectors were a luxury. Now their cost is still high, but it fits into the acceptable range for consumers. The price of high-quality models starts from 1 thousand dollars.
It is noteworthy that the 4K resolution in most projectors is not entirely fair – it is achieved through pixel shift technology. It superimposes four Full HD images on top of each other, shifting the image up, down, left, or right by half a pixel fast enough that the naked eye doesn’t recognize it.
There are honest 4K models on the market, but prices start at $6,000. Their main advantage over pixel-shifted counterparts is a more detailed picture. Also, these projectors can create 8K images using pixel shifting.
As for projectors with Full HD resolution, these are devices of the budget price segment. On a 100-inch screen, the pixels will be striking, but there is no more affordable way to get a huge image.
When it comes to projectors, we think of a massive box that mounts to the ceiling. However, in recent years, many models have come out with a fundamentally different design.
Due to the reduction of internal components, portable models have appeared, such as the Nebula Capsule. The projector can work from the built-in battery and fits easily into a backpack, you can take it on a visit or on a picnic. The laser source provides sufficient brightness for most users, though not comparable to stationary solutions.
Portable models such as Nebula Cosmos, XGIMI H6 and JMGO N1 have also appeared on the market. They can be mounted on any flat surface, as well as on a tripod. These projectors are equipped with an ambient light sensor, autofocus, optical zoom and a screen border detection system, so the setup process is as simple as possible.
Short-focus models, also called laser TVs, deserve special mention. They can be installed at a distance of only 30 cm from the wall on which the special ALR screen is mounted. The latter has a special texture and absorbs all the light, except for the one coming from the bottom of the projector.
The main players in this segment are Hisense and Samsung. As you might guess, such projectors use a laser – in flagship models like the Samsung LSP9T there are three of them at once. The cost of such devices varies from two to five thousand dollars. A high-quality ALR screen will cost another 500-1000 dollars, depending on the diagonal.
What else to pay attention to
Projectors from well-known manufacturers often come with proprietary operating systems. In Samsung’s case, it’s Tizen OS, LG’s models offer Web OS, and Hisense’s projectors run VIDAA.
Chinese brands often use Google TV as their operating system. However, there are those who offer their own firmware, unfamiliar outside of China. Many of them lack localization – at best, you will be offered a choice between Chinese and English. There are also projectors that work from an external set-top box connected via HDMI.
Connectors and interfaces
The standard set of connectors for the projector includes several HDMIs, one of which supports eARC for connecting a soundbar or audio receiver. If you have old cinema acoustics, the presence of an S / PDIF connector may come in handy. Also, most modern models support a Bluetooth connection.
Many projectors offer USB ports for playback from a flash drive. The function is useful if there is no separate media player.
One of the main characteristics of the image in projectors. In projectors, brightness is measured in units of ANSI Lumen (Lm). The larger the diagonal of the projection screen, the higher the brightness of the projector should be. The distance to the screen and room parameters are also important. Below is a table with the necessary brightness parameters for screens of different diagonals and proportions.
It is important to remember that the measurement standard in ANSI Lm does not allow you to compare projectors of different types and with different light sources. So, laser and LED models with the same declared brightness will give subjectively different results.
High dynamic range video is becoming more and more popular. Flagship projectors support HDR10, HDR10+ and Dolby Vision standards, allowing them to read video brightness metadata and display it adequately on the screen. However, there is a nuance here.
HDR video metadata indicates brightness in cd/m2, or nits. Often this indicator exceeds 1000 nits. In order for such video to be displayed without highlights, tone mapping is performed, which reduces the brightness to the capabilities of the equipment.
In the case of premium TVs, this is not a problem – their peak brightness often reaches 1000 nits, which is enough for a high-quality HDR effect. However, even the most advanced projectors are not capable of producing such brightness.
Because of this, the video stream is squeezed into an extremely limited brightness window. Such video will be very dark and often perceived worse than standard SDR. So chasing the HDR effect in projectors is not worth it.
Over the past couple of years, “gaming” projectors with 120Hz refresh rates have been on the market. For most, the resolution is limited to 1080p. All because of the already mentioned pixel shift technology, which significantly increases the response time.
There are already models in the premium segment that support 4K at 120Hz. For example, Epson LS12000. However, the cost of 5 thousand dollars is unlikely to make the projector popular among gamers.
Traditional projectors are often devoid of a speaker system – it is assumed that the sound will be output to external speakers. With portable and portable models, the situation is different, since ease of use is at the forefront.
Laser TVs also have their own speakers. In addition, they can be used as a center channel in theater acoustics.
Choosing a projector depends on many factors. Under what conditions do you plan to use it? Are you ready to sacrifice picture quality for the sake of portability and mobility? What is more important: resolution or refresh rate?
Some take the projector solely for the sake of a large diagonal – it’s much cheaper than buying a 100-inch TV. But if you want a truly cinematic experience, don’t forget that you will also have to invest in a projection screen and acoustics. If you do everything right, the magic of cinema will sparkle with new colors.
Source: Mobile-review.com — Все о мобильной технике и технологиях by mobile-review.com.
*The article has been translated based on the content of Mobile-review.com — Все о мобильной технике и технологиях by mobile-review.com. If there is any problem regarding the content, copyright, please leave a report below the article. We will try to process as quickly as possible to protect the rights of the author. Thank you very much!
*We just want readers to access information more quickly and easily with other multilingual content, instead of information only available in a certain language.
*We always respect the copyright of the content of the author and always include the original link of the source article.If the author disagrees, just leave the report below the article, the article will be edited or deleted at the request of the author. Thanks very much! Best regards!