Video projection

Video projection

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A video projector is an image projector that receives a video signal and projects the corresponding image on a projection screen using a lens system. Hubtech limited Video projectors use a very bright Ultra-high-performance lamp to provide the illumination required to project the image. Most modern ones can correct any curves, blurriness, and other inconsistencies through manual settings. If you use a blue laser, a phosphor wheel turns blue light into white light.

A wheel prolongs the lifespan of the phosphor, as heat generated by the laser diode degrades it. Remote fiber optic RGB laser racks are usually placed far away from projector, and several racks are often housed in a single, central room. Each projector can use up to two racks. Also, monochrome lasers mount on each rack, the light of which is usually mixed and transmitted to the projector booth using optical fibers. Projectors using RB lasers use a blue laser with a phosphor wheel in conjunction with a conventional solid-state red laser.


Hubtech limited projectors are usually used for many applications such as conference room presentations, classroom training, home cinema, movie theaters, and concerts. In schools and other educational settings, they are sometimes connected to an interactive whiteboard. In the late 20th century they became commonplace in home cinema. Although large LCD television screens became quite popular, video projectors are still common among many home theater enthusiasts.

Video projector projects onto a traditional reflective projection forming a single unified display device.

Common display resolutions include SVGA (800×600 pixels), XGA (1024×768 pixels), SXGA+ (1400x1050 pixels), 720p (1280×720 pixels), and 1080p (1920×1080 pixels), 4K UHD (3840x2160). It also includes 16:10 aspect ratio resolutions including WXGA+ (1280x800 pixels) and WUXGA (1920x1200 pixels).

Projection technologies

LCD projector using LCD light gates. This is the simplest system, making it one of the most common and affordable for home theaters and business use. Common problems include a visible “screen door” or pixelation effect. LCD panels also deteriorate from heat & UV rays, leading to discolored spots or holes in the image. However, recent advances have reduced the severity of these issues in some models.

DLP projector using Texas Instruments’ DLP technology. This uses one, two, or three microfabricated light valves called digital micromirror devices (DMDs). The single- and double-DMD versions use rotating color wheels in time with the mirror refreshes to modulate color. The most common problem with the single- or two-DMD varieties is a visible “rainbow” that some people perceive when moving their eyes. More recent projectors with higher speed (2x or 4x) and otherwise optimized color wheels have lessened this effect. 3-chip DLP projectors do not have this problem, as they display each primary color simultaneously. They offer higher light output and more accurate color reproduction. However, the cost is significantly higher thus 3-chip DLP technology is typically used in large venues, high brightness models, and Digital Cinema projectors.

LCoS projectors (liquid crystal on silicon). Such projectors often process light in the Fourier domain, which enables the correction of optical aberrations using Zernike polynomials. Some commercially available technologies include:

·??????D-ILA JVC’s Direct-drive Image Light Amplifier is usually based on LCoS technology.

·??????SXRD Sony’s proprietary variant of LCoS technology.

LED projectors use an array of Light Emitting Diodes as the light source, negating the need for lamp replacement.

Hybrid LED and laser diode system developed by Casio. Uses a combination of Light Emitting Diodes and 445 nm laser diodes as the light source, while DLP (DMD) chip processes the image.

Microvision and Aaxa Technologies developed Laser diode projectors. Microvision projectors use Microvision's patented MEMS laser beam-steering technology, whereas Aaxa Technologies uses laser diodes + LCoS.

Laser projectors are now available from most projector manufacturers, including Barco, Canon, Christie Digital, Dell, Epson, Hitachi, NEC, Optoma, Panasonic, Sony, Viewsonic, etc. These units use a laser light source and are usually used with common projection technologies, including Single & 3-Chip DLP, LCD, and LCoS. They eliminate the high cost and downtime of replacing lamps, variations in brightness and color that occur as lamps age, and improved color fidelity. Typical laser light sources used in projectors rate for 20,000 hours before the light output reduces to 50%.

Features to consider when buying our projectors.

Contrast

The contrast in video displays is usually expressed in a ratio, as in 1,000,000:1 or 1,000:1. It refers to the difference between the darkest black and the whitest white. You want your projector to be capable of beaming a bright pure field of snow as well as the deep black of the night sky. For some projectors that are a real challenge, and that challenge is always exacerbated by room light and a poorly matched screen. Note that the contrast number quoted on most projector spec sheets is, well, hopeful. Often it’s measured in what the industry called full-on/full-off, which is not a real-world measurement.

Color accuracy and adjustments

You want your projector to display accurate colors, of course. You want reds to look red and greens to look green, but getting accurate colors is often in the projector’s settings and adjustments. The more detailed the adjustments, the better you can dial in the color. Projectors with ISF (Imaging Science Foundation) and THX certifications will all have good color adjustment features or calibration. Their default movie or cinema modes will often be better than non-certified projectors as well (often, not always).

Lens zoom

All our projectors except possibly desktop models used for business presentations (and those pocket-sized pico projectors) include a zoom lens. The zoom allows you some leeway forward and backward when positioning your projector in front of the home theater screen. A large zoom ratio gives you a little more wiggle room, but using too much zoom can enhance chromatic errors in the picture. A good combination is to pick a projector with a large lens and large zoom. However, a better practice is to follow the manufacturer’s throw distance suggestions.

Lens shift.

Because sometimes we can’t get the perfect mounting position, better projectors often feature lens shifts, both vertical and horizontal lens shifts are available. This feature allows you to slightly move the lens up/down, left/right after mounted to perfectly align the projector’s image on the screen. Some projector mounts also have similar adjustments built in.

Light output

DPI_INSIGHT_4K_LEDBrightness is probably the first thing a lot of people look for when home theater projector shopping. Bright pictures are good, but a picture that’s too bright for the room or screen size will end up fatiguing the viewers. Many affordable projectors sport brightness in the 1,000 to 2,500-lumen range, and that’s enough for most modest-sized media rooms with 100 to 140-inch screens. That amount of light, when matched with a screen helps maximize light output. If you have a very big room or demand a very big screen then look for a brighter projector. The super bright projectors sporting 10,000 lumens are only necessary for extremely large rooms with screenzillas.

Low Noise

Home theater projectors are always stuffed with moving parts—cooling fans, color wheels, motorized iris controls, and more. All those moving parts can make some noise. Also, when your movie is in a quiet and suspenseful moment, you don’t want the experience ruined by a loud cooling fan.

Resolution

The last of the big three specs is resolution. The first thing you’ll notice when shopping is that 99 percent of all home theater projectors are 1080p resolution (1920 x 1080 pixels). Only very inexpensive projectors are usually offered in 720p, anymore. This means that, for the most part, you don’t need to worry about resolution since most projectors output the same number of pixels. However, a slowly growing trend in projectors is for 4K resolution which is four times the number of pixels of a 1080p projector. Currently, there are only a few 4K projectors used in home theaters. However, that number will probably increase soon, as 4K TVs are taking over the TV market quickly. A 4K projector has the benefit of allowing you to use a larger screen because the pixels themselves will be much smaller.

Hubtech limited offers the following Brands of projectors

Epson projector

Epson delivers a comprehensive projector and displays solutions that enhance communication and inspire collaboration

·??????High-quality bright images: 3LCD technology and equally high White and Color Light Output

·??????Portable: Small and light enough to be always carried and used across several rooms

·??????Wide connectivity options: Network-enabled and wireless capable

·??????Low total cost of ownership: Lamp life up to 12,000 hours in Eco mode

·??????Versatile and flexible control: Project from many sources with HDMI and optional wireless connectivity

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Sony projector

Sony projectors are usually designed in such a way that it is fit for small and medium classrooms. It can shine in any of the meeting places.

·??????It has the capability of delivering clear kinds of presentations and pictures. You can adjust it according to your choice and needs.

·??????It is always designed in the most upgraded form and it is dust resistant Considered reliable of functioning and has proper operation and maintenance. It is available in the mainstream media market with the best ranges.

·??????Instead, you can visit this site and get the best products available at a reasonable price. Also, it has shown the new standard and can connect to a television or in any form of the media room.

·??????It can create a theater in the luxury home which can be as interesting and beautiful. It has all the features which have the quality of being the standard and best.

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Projection screen

A projection screen is an installation consisting of a surface and a support structure. It displays a projected image for the view of an audience. Projection screens may be permanently installed, as in a movie theater; painted on the wall. Another popular type of portable screen is inflatable screens for outdoor movie screenings (open air cinema).


Uniformly white or grey screens are always used almost exclusively to avoid any discoloration of the image. Most desired brightness of the screen depends on several variables, such as the ambient light level and the luminous power of the image source. Flat or curved screens may be often used depending on the optics used to project image and the desired geometrical accuracy of the image production. Screens can be further designed for front or back projection. These are the more common front projection systems, which have the image source situated on the same side of the screen as the audience.

Hubtech limited Screens by installation type in different settings

In commercial movie theaters, the screen is a reflective surface that aluminizes (for high contrast in moderate ambient light). Also, the screen can be a white surface with small glass beads (for high brilliance under dark conditions). The screen has hundreds of small, evenly spaced holes to allow air to and from the speakers and subwoofer, which often are directly behind it.

Rigid wall-mounted screens maintain their geometry perfectly which makes them suitable for applications that demand exact reproduction of image geometry. Such screens are often used in home theaters, along with pull-down screens.

Pull-down screens (also known as manual wall screens) are often used in spaces where a permanently installed screen would require too much space. These commonly use painted fabric that rolls in the screen case, making them less obtrusive when the screen is not in use.

Fixed-frame screens provide the greatest level of uniform tension on the surface of the screen, resulting in optimal image quality. They are often used in home theater and professional environments where the screen does not need to recess into the case.

Electric screens can be wall-mounted, ceiling-mounted, or ceiling recessed. These are often larger screens, though electric screens are available for home theater use as well. Also, Electric screens use an electric motor to raise and lower the screen. Electric screens are usually raised or lowered using either remote control or a wall-mounted switch. Some projectors are usually equipped with an interface that connects to the screen. These automatically lowers the screen when the projector switches on and raises it when the projector switches off.

Switchable projection screens switch between opaque and clear. In the opaque state, the projected image on the screen can be always viewed from both sides. It is very good for advertising on store windows.Mobile screens usually use either a pull-down screen on a free stand or a pull-up from a weighted base. These can be often used when it is impossible or impractical to mount the screen to a wall or a ceiling.

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