The Use of Projector Corrected
The Use of Projector Corrected
The Use of Projector Corrected
What Is a Projector?
A Projector is a device designed to take an image from a video source and project it as faithfully as possible onto a screen or other surface. Projectors are used in a variety of different ways; they are enjoyed by home theater enthusiasts due to their ability to project movies and television programs onto a screen much larger than even the biggest TV available, and used in the corporate setting to project information onto screens large enough for rooms fi lled with people to see. Projectors come in a variety of different shapes and sizes and are produced by many different companies. A Projector is designed to receive a video signal from some external device -usually a DVD player, a Blu-Ray player, or a computer-and project that signal onto a screen. It does this by displaying the image represented in the video signal onto a small screen inside the projector itself, which is then projected onto a screen using a bright light and a lens. The lens is a piece of glass shaped in a very specific way designed to take the small image and turn it into a dramatically larger one. Projectors allow users to alter a variety of image features, including brightness, sharpness and color settings, in the same way a standard tele vision would.
Evolution of Projector
Corporate America was first introduced to projection technology in the 1950s. Although the technology itself has changed dramatically since that time, conceptually it has remained the same. The opaque projectors which were the sole option of the 50s have given way to a multitude of options in the 21st century where ones choice of technology will likely hinge on the material to be projected.
Opaque Projectors - One of the earliest forms of projection, the opaque projec tor, allows the user to project printed material or small objects without having to convert them to another medium. An example of such an application would be projecting the contents of single page of a book onto a wall. This is achieved by turning to the page and placing the entire book into in the opaque projector.
In use for nearly sixty years, the opaque projector projects the object by shining a bright lamp on the material to be viewed and directing the reflected light through a projection lens. Documents, photos, magazines, books, and small 3-dimensional objects can be projected with the opaque projector provided the user remains mindful of the heat generated by the light source and the potential for damage to heat sensitive documents or objects.
Slide Projectors - Slide projectors have also been around since the 1950's.
Unlike opaque projectors, slide projectors require that the presented material be transferred to a 35mm slide allowing the user to project virtually anything that can be can put on film. While there is a cost associated with creating slides, the benefit is the versatility of the device. Kodak, the leading supplier of slide
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projectors, discontinued production in October 2004. Regardless, there is still a market for slide projectors as other companies still include them in their product lineup. Overhead Projectors - In some ways an overhead projector is very much like a slide projector in that the information to be viewed must be transferred to another medium, in this case a transparent sheet of flexible material known as a transparency. A transparency of any document can be easily generated with a copy machine. Once created, the transparency can be placed on an overhead projector and projected onto a wall or screen using a lamp and optics that are built into the projector. One of the benefits of the overhead projector is the ability to annotate the projected image while presenting. Overhead projectors are still widely used.
Digital Projection Panels - In the late 1980's overhead projectors found further use with the introduction of digital projection panels.
The digital projection panel consisted of a large LCD, electronics, cooling fan, and a plastic or metal enclosure with a glass plate on both sides of the LCD. The LCD was similar in size to that found in a notebook computer except that the electronics on the back of the LCD were unfolded to allow light from the overhead projector to pass through the LCD. A digital projection panel was essentially an electronic sheet of paper in a box about the size of a large book that when plugged into a computer coul d display the image using the light and optics of the overhead projector. It effectively became a giant monitor for the computer allowing fully interactive presentation, education, and training making them the first digital projectors. Within a year of their introduction, video projector panels were introduced and were quickly followed by multimedia projector panels that could support video and data. Projection panels are still in use, but as prices drop and performance continues to improve, they are quickly being replaced by data projectors, video projectors and multimedia projectors.
Computer Projectors - the fully integrated digital data projector came into existence in the early 1990's and served primarily as a computer display projector for business, education and training.
It essentially combined the overhead projector and the digital projection panel into one device making it considerably smaller and more easily transported. As is true with most new technologies, the first offerings of the compute r projector were big, heavy and expensive with image quality that pales in comparison to today's projectors. As the computer projectors got smaller, lighter, and cheaper they became popular with mobile presenters. Today data projectors are used in a wide range of applications including mobile presentations, conference rooms, classrooms, training, gaming, simulation, control rooms, museums, and retail advertising.
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Video Projectors - The digital video projector also came into being in the early 1990's and like the early computer projectors, they were large, heavy and expensive.
They also suffered from poor image quality, high cost, and limited portability. But much has changed since the video projectors of the early 1990's arrived. Today you can buy a home theater projector and enjoy a high definition movie with quality that is comparable to or better than your local movie theater. And you don't have to worry about the sticky floors, expensive popcorn and the talkative kid that keeps kicking your seat. Video projectors also serve nicely as TV projectors that can project your sate llite receiver programming or local broadcasts. With todays TV projector you can also attach a DVD player or any of the high definition DVD players and enjoy a movie of your choosing. There are even TV projectors with integrated DVD players and audio syst ems that provide a video boom-box for home entertainment that can be easily taken from room to room with minimum setup.
Home Theatre Projectors - The home theater projector is perhaps the most rapidly growing market segment now that a home movie theater ex perience is possible for a very nominal cost for the do-it-yourselfer.
For those not inclined to install their own home theater projector, there are plenty of installers available for hire. Some of our home theater enthusiasts have converted basements, spare bedrooms and living rooms into home theaters. A home theater projector can achieve a 100+ inch image for a fraction of the cost of LCD or plasma flat panel. These home theater systems now compete with the neighborhood cinema and to remain competitive many movie houses are replacing their film projectors with high definition digital projectors, a larger version of the type one would buy for the home.
Multimedia Projectors - The early multimedia projectors combine d video, data and audio as a universal solution.
Todays data and video projectors are essentially multimedia projectors as almost all of them support data and video in one form or another. Since a good audio system needs power and separation, todays projectors do not serve well as a primary audio source for any high quality audio, but they can be useful in a small presentation room. In addition, some multimedia projectors support wireless presentations and wireless high definition. The latter is currently an add-on that allows an HD projector to connect to a high definition video source without the need to run wiring. In time this may become a common component of the projector.
Pocket Projectors - The first pocket projectors were introduced in 2005 by Mitsubishi and they were small enough to fit in the palm of a hand.
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Their light source is a cluster of LEDs and most of them can be plugged into a wall outlet or powered by battery. Their biggest drawback is the lumen output which in the first few years of shipment, was about 25 ANSI lumens. The future of pocket projectors is very promising as optics are reduced, light output improved, packaging reduced, and prices fit for a consumer market. We expect to see the technology in everything from toys to portable computers.
Conclusion The projection industry has come full circle. Today a multimedia projector brings back many of the features found on the opaque projector, slide projector and overhead projector through the use of document cameras. These handy devices can be connected to any projector, or in so me cases, they are integrated into the projector, giving the presenter the opportunity to project a document, transparency, or 3 dimensional object.
What is perhaps the greatest achievement in the evolution of this technology is how rapidly the performance improved and the size diminished while prices continued to fall. In the coming years you can expect to see smaller, lighter and cheaper projectors with better resolution and performance as new technologies such as lasers, LEDs and electrode-less lamps emerge.
Projection screen
A projection screen is an installation consisting of a surface and a support structure used for displaying a projected image for the view of an audience. Projection screens may be permanently installed, as in a movie theater; painted on the wall;[1] or semipermanent or mobile, as in a conference room or other non-dedicated viewing space such as an outdoor movie screening (open air cinema). Uniformly white or grey screens are used almost exclusively as to avoid any discoloration to the image, while the most desired brightness of the screen depends on a number of variables, such as the ambient light level and the luminous power of the image source. Flat or curved screens may be used depending on the optics used to project the image and the desired geometrical accuracy of the image production, flat screens being the more common of the two. Screens can be further designed for front or back projection, the more common front projection systems having the image source situ ated on the same side of the screen as the audience.
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Don't unplug your projector until you get the OK from your projector. This is the largest way a projector lamp will fail; don't unplug your projector for around one or even two minutes after you have finished using it. This allows the projector lamp to cool a bit. Even if you have a projector that says you need no cool down time, still wait at least a minute just to ensure that you don't have a projector lamp burning out before it should. Make sure to clean the filters or change them as needed. N o matter what kind of projector you have, most of those will have a recommendation to clean those filters, probably after 100 hours of usage. Most people won't follow these rules, and may wait until after 800 hours or so. All this does is shorten the lifet ime of a projector lamp. Watch where you place your projector while using it, as the spot you pick may cause overheating. One of the worst spots to put your projector is right up against a wall; this will not allow for good air circulation and will cause the projector to overheat. Try to leave at least 6 from a wall. Use the eco-mode of operation on your projector. This is one of the best ways to extend your lifetime of the projector lamp. Plus the fan will be a bit more quiet because it won't have to run nearly as fast.
High-Definition Interface
Multi-media
Typical Application High end DVD players to high end display devices. Summary HDMI is a relatively new connection but is quickly becoming the standard to connect home cinema components , being a digital equivalent of the popular 'SCART' format. Like SCART, HDMI can carry both video and audio, and so minimises on untidy wires.
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There are two types of HDMI connections; The standard Type A HDMI connector has 19 pins, and the other; Type B has 29 pins, allowing it to carry an expanded video channel for use with high-resolution displays. Type-B is designed to support resolutions higher than 1080i.
S-Video Also Known As Quality
Typical Application Television to VCR DVD player to Display device. Summary S-Video cables differ from composite cables in that they split the video signal into two different components: Luminance and Chrominance. N.B. The S -Video cable will offer marked improvement over a composite cable. Composite VideoAlso Known As Quality
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Typical Application Digital satellite and cable boxes. Links stereo, televisions and video recorders. Summary N.B. Scart can be converted via an adaptor to composite and S -Video. VGA Also Known As Quality
Typical Application Digital to Digital connection between video/data source and display device. Summary DVI-Digital Video Interface. Developed for a plug and play standard. The digital connection automatically optimises your data source to work with the display device. DVI-D is a digital only connector. DVI -I can support both digital and analog inputs. RS232 Also Known As Quality
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Typical Application Standard Network Port Summary The RS232 standard describes a communication method capable of communicating in different environments. PS/2 Also Known As Quality
Mouse Connector
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Typical Application Connects mouse to mother board or serial port. Summary A round 6-pin DIN connector. This port creates an interface between the computer and the projector, allowing the remote control to have access to both projector and computer functions. PC AudioAlso Known As Quality