clean lcd panel epson projector quotation

Do not use glass cleaner or any harsh materials to clean the lens and do not subject the lens to any impacts; you may damage it. Do not use canned air, or the gases may leave a residue. Avoid touching the lens with your bare hands to prevent fingerprints on or damage to the lens surface.

The Epson Home Cinema 730HD Projector is my second Epson projector, having bought an EX-70 about 7 years ago. I moved from the EX-70 to a 60inch t.v. as my room at my previous address was still too bright for a projector and the replacement lamps for the EX-70 were for me too pricey having to buy 2 during the time of my EX-70. But a large screen from a projector is a very compelling thing (mine was 84 inches with the EX-70) and I missed that even with a still large 60 in flat screen t.v.

Time passes by and the thoughts of redoing a front projection set up in my media room, in my new home address which has less ambient window light than my old address, was on my mind. I began to read up on more affordable home entertainment style projectors. Output lumens have increased over the last number of years with these projectors, so more research led me back to tried and true Epson. I like the 3 chip LCD idea for the high white and high color lumens. Using a variety of online sources I found the modestly priced Epson Home Cinema Projectors to be workable in room with ample daylight and for those like me who do not want to watch t.v., movies and concert videos in total darkness and as such leave some lighting on while watching at night.

I had to choose how much money did I want to invest back into a front projection set up again, this will determine if I go 1080p or can I settle on 720p (The 730HD is 720p in 16:9 mode, in its native 16:10 mode its 1280x800p). My previous EX-70 was also 720p and I recall it being high enough resolution and clear enough image wise in my previous media room sitting about 9 ft. away from the screen. My current media room has me sitting oh about 9 1/2ft. away from the screen (about 91" diagonal 16:9). Yes, 1080p projectors are obviously higher resolution and yes will technically be better, but a comparable Epson 1080p projector I found on sale at the time of my purchase was $749.95 Cdn. A darn good price, but I really want to keep my budget tighter as I will have to also buy a proper wall mount, a 50ft. HDMI cable (4K ready as in future I will one day get a 4 K projector so may as well get a 4K ready HDMI cable), a spare lamp (I recommend any projector user to always keep one spare lamp handy) and for myself the materials to make my own large fixed screen. So even though the 1080p projector on sale was a good price I saw here at Amazon.ca the Epson Home Cinema 730HD LCD Projector at a refurbished price of $375.00 Cdn. In my opinion a very good value.

So I bought this projector and have since set it up and finished my DIY painted screen. As to the screen and its impact on my viewing I had to choose to have cut 49" x 78" a 1/2inch sheet of MDF. My wall used is just too uneven from a low quality build by the contractor who finished the room and from settling and repairs to the drywall over the years of this home"s age. So I mounted the 730HD where I want it to project its image. Marked out a 49" x 78" image on the wall. I pre-drilled to fit wood screws through and to counter sink them into the MDF and hung it covering through 4 studs on the top and 2 studs on the bottom of the MDF to hold it in place.

I then filled and sanded the screw heads to cover them from showing. I rolled on with a low nap roller a primer/sealer coat and chose to let it dry over night. Now as to DIY screen colors. Lots of stuff over the web on DIY screens and painting. One can buy commercial grade paints and obviously will give you tried and true quality at a higher price. These pro grade choices may be for some front projector buyers. For me I chose to read and interpret DIY paint choices and I rolled the dice to settle on the following choice for me.

I bought 4 liters of Behr latex paint, tinted to N500-6 Graphic Charcoal. I bought a 1 litre tin of Ralph Lauren un-tinted Metallic. I first painted the wall area where my MDF screen will hang giving it a dark gray color. After I hung and primed my 49"x78" x 1/2" MDF screen. I made my chosen mix. In a clean empty coffee tin I poured 1 litre of the N500-6 Graphic Charcoal with the 1 litre of Ralph Lauren un-tinted Metallic. Using a hand mixer with mixing tools I mixed the paints for a good 3 minutes. A low nap 9 inch roller and a clean paint tray had me begin to roll out my screen color. Slowly, smoothly from bottom to top and back to bottom over and over being careful to not over fill the roller but not spread it too thin either taking care not to press too hard and to make sure roller lines did not show. After a few minutes my first coat was done. I wrapped the roller in a plastic bag tightly to keep it from drying out. I wrapped the paint tray in a plastic bag to keep it from drying out too. I waited for 2 hours and then lightly sanded with 400 grit paper the wall to smooth down the first coat and to help give grip to the second coat. I then wiped the wall down with clear water and a damp micro-fibre cloth. I let it dry and I then did the same rolling procedure for my second coat and when done I let it dry. I found two coats to be enough, but I have ample mixture left over if I have to do a third coat.

This DIY choice has given me a me a deep gray base and the metallic well mixed in, increases output for higher contrast. The 730HD has 3000lumens max. output but I have mine in Eco mode and it"s about 2000lumens. The screen I made will help give me a credible picture for even daytime viewing where I do have noticeable daylight into my media room but not flooded with daylight. All projectors will be more affected by daylight than a t.v., but based on the pictures I supplied in my room taken during the brightest time of the day still gives to me an acceptable 91" diagonal viewing experience. At night even with two equal to 40 watt LED bulbs in small lamps on, the screen color I made gives a very good image, turning off one lamp that shines more light at the DIY screen and BOOM the color and contrast then pops like a 91" big t.v.

Epson home cinema projectors do not have the lower black levels of competing DLP"s but have better whites and colors. My dark gray with metallic screen color gives very credible black levels for the 730HD but still gives great color. I have not yet run a proper set up disc such as my Speer"s and Munsil Blu ray disc (BTW all THX Blu ray movie discs will have in menu a THX optimizer that one can use to set up picture on your t.v. or projectors). I just have my 730HD in "Living Room" mode where I dropped the sharpness down a few points and contrast up by two points.

The 730HD makes a crisp, clear, colorful HD picture even at 720p. To my eyes sitting about 9 1/2 ft away from my screen, HD cable t.v. looks great and Blu ray movies and concert videos look excellent. If you are on a budget but still want a MOVIE THEATRE image type size experience well this refurbished 730HD projector is a great deal. Yes, if your budget allows you to spend more, say over $750.00Cdn, then a comparable Epson 1040 (1080p) will give you all I noted here and 1080p HD will be a great alternative... But. I"m loving my 730HD projector and all in all costs, materials etc I"m in for about $700 Cdn. Again the supplied pics are straight out of camera and shot during the day where the daylight entering the room is brightest. It"s a still a watchable image and for me at about $700.00 Cdn. total investment for all I get a 91" diagonal ( 16:9) viewing experience... I"m very satisfied and beginning to re-watch my favorite movies and concert videos at this size is way cool!

The BenQ TH585P 1080p DLP projector is the lower-priced sibling of the TH685P we discuss in Other good budget projectors under $1,000. In terms of picture quality, it looks very similar to the TH685P and has the same performance limitations (mediocre contrast, color, and black-level performance, plus light spill around the screen), plus the built-in speaker is just dreadful—so movie lovers will be much happier if they spend a bit more to get the HT2050A. And for gamers, we like the TH685P’s better complement of features: 4K HDR signal input, 120 Hz refresh rate, better built-in speakers, and slightly short throw ratio and higher zoom for easier image placement.

Epson’s Home Cinema 880, which is the lowest priced model in the company’s Home Cinema line, is a mixed bag. On the one hand, it’s one of the brightest projectors we’ve tested for this guide, measuring 3,160 lumens in the Dynamic picture mode and 2,276 lumens in the Game picture mode, which is also very color-accurate. I had no problem watching movies, TV shows, and sports on my 84-inch-diagonal screen during the day, even with the window blinds open. But the 880 also had the worst black level and one of the worst contrast ratios of any projector we’ve measured, so movies—even in bright scenes—looked flatter and more washed out. Plus there’s no optical zoom or lens shift and only one HDMI input, and the fan noise is loud at maximum brightness. We can’t recommend the Home Cinema 880 for movies, but if you need a more affordable projector for daytime use—especially for gaming and sports—this one might be worth a look. The newer 880X is basically the same projector packaged with an Android TV stick and a carrying case.

The Epson Home Cinema 2200 is almost identical to the Home Cinema 2250 in its features, except it has a lower zoom of 1.2x and no lens-shifting capabilities. In a direct comparison with the Home Cinema 2250, we found that the Home Cinema 2200 had a greenish push to the color temperature and a higher black level, resulting in lower contrast. We think paying a little more for the Home Cinema 2250 is worth it, especially for movie-watching in a dim to dark room—but if you find this model on sale, it is a solid choice for bright-room viewing.

Epson’s EF-100 was the company’s first “mini” LCD projector. It has a small, portable (but not battery-powered) form, a laser light source, and a stated brightness of 2,000 lumens, but only a 1280×800 resolution. It comes with an Android TV stick for streaming video. We did not review this projector, but regular Wirecutter contributor Geoff Morrison reviewed it for CNET, comparing it directly with the BenQ HT2050A. He found that, although it had comparable brightness, its contrast and black level were much worse. The newer EF11 and EF12 (which adds Android TV) have a 1080p resolution but are less bright (a claimed 1,000 lumens). With selling prices around $800 and $1,000, respectively, these mini projectors are quite pricey for what you get. For a similar price, the Home Cinema 2250 is a much better performer.

The Fangor F-405 is a sub-$300 LCD projector sold almost exclusively through Amazon. The picture quality on this one is flawed but not horrible. It didn’t have the major brightness-uniformity and focus issues we saw with the similarly priced Yaber Pro V7, and the black level was decent—but this projector was even dimmer than the Yaber (only measuring 266 lumens) and had the worst color accuracy we’ve measured in a long time. The color temperature (or color of white) is really green—with minimal adjustments available—and this projector can only reproduce 70% of the color gamut for HD video (most projectors come in above 90%). But if you’re willing to forgive the color problems, it’s a watchable image for the occasional movie night, and it comes with features like Bluetooth audio output and Wi-Fi screen mirroring. The biggest frustrations here are ergonomic: The power cord has a big DC brick in the middle that makes it hang heavily and awkwardly, there’s no zoom and lens shift, and the F-405 casts the image 20 inches lower than the BenQ HT2050A—so to get the image up on the wall or screen, you have to place the projector on a higher surface or aim it up and use more keystone adjustment (and there isn’t much of it to work with).

The Optoma HD39HDR is a gaming-oriented 1080p DLP projector. It accepts a 4K signal (and downscales it to 1080p), supports HDR10 playback, and has a 120 Hz refresh rate and a gaming mode with low input lag. This projector is very bright, but its measured contrast is lower than our picks, and it’s not as color-accurate. Plus, it reproduces much less of the HD color gamut than other DLP projectors we’ve tested, like the newer BenQ TH685P. It’s also slow to switch between different frame rates and resolutions.

We did not review the Optoma HD28HDR, a lower-priced sibling of the HD39HDR that has a slightly lower stated brightness (3,600 versus 4,000 lumens). Like the HD39HDR, it accepts a 4K signal (downconverting it to 1080p), supports HDR10 playback, and has a 120 Hz refresh rate and low input lag for gaming. It has no lens shift and only limited 1.1x zoom. Geoff Morrison reviewed this projector for CNET and found that, while it does look good with HDR content if you watch a lot of that, the BenQ HT2050A is a better overall performer.

Vankyo offers a number of sub-$300 LCD projectors, similar to the models from Yaber and Fangor that we tested. While these projectors mostly have small form factors, a 1080p resolution, and Wi-Fi streaming, they have low light output that is not ideal for big-screen home theater viewing. The V630 is one of the company’s “higher-performance” models, and after reading this thorough comparison with the BenQ TH585 (the older version of the TH585P) on ProjectorReviews.com, we decided not to test it.

The Viewsonic PX701-4K is one of the few 4K DLP options currently available under $1,000, and it’s a decent overall performer, delivering a crisp, bright 4K picture. The Game and Movie picture modes have a pleasingly neutral color temperature (or color of white) right out of the box, with less of a greenish-blue tint in brighter scenes than the HT2050A. But the black level and contrast are not as good as our picks, so movies look so somewhat flat by comparison. The bigger concern is that the colors look too dark and undersaturated by default. The PX701-4K uses DLP BrilliantColor technology to improve image brightness at the expense of color accuracy; you can turn the BrilliantColor function down or off to make colors look brighter and more accurate, but you’ll lose overall brightness and contrast in the process. An experienced calibrator could help set up this projector to get the best balance between brightness and accuracy, but the similarly priced Epson Home Cinema 2250 delivers this balance right out of the box, just without the 4K HDR support. Also Viewsonic omits features like lens shift and optical zoom, so this projector has less placement flexibility.

ViewSonic’s PX727HD is a good-performing 1080p DLP projector in the same price range as the BenQ HT2050A. In our tests, the picture was clean and detailed, the color temperature (or color of white) was more accurate than the BenQ HT2050A’s, and its color was almost as accurate. It wasn’t as bright as the HT2050A, and its overall contrast wasn’t as good—but its black level was better than that of many of the other projectors we tested, without the use of a dynamic lamp or iris mode. If you’re looking for a projector to use primarily in a dim to dark room and the HT2050A is unavailable, this model is a good choice.

Yaber’s Pro V7 is another low-priced 1080p LCD projector sold primarily through Amazon. Despite its ridiculous claimed light output of “9500 L,” we measured 316 lumens (16.6 ft-L) on our 84-inch-diagonal screen, which is not even a quarter of our top pick’s capabilities and more in line with some of the mini projectors we"ve tested. Its color accuracy is average at best, and the included picture adjustments don"t help much. The 1080p image consistently looked a bit soft and unfocused, no matter how much we fiddled with the manual focus dial. And the brightness uniformity was very poor—when we put up an all-black test screen, we saw large patches of light around the screen (like a low-quality LCD TV screen), and this was evident in dark movie scenes. There’s also no physical lens shift or zoom to help position the image on your screen.

Choosing for Room Size/Viewing Distance Every projector has a throw ratio. This refers to the size of image the projector can create for a given distance. This is usually a range, thanks to the optical zoom – you can find it in the user manual or specifications page online (if it"s for a projector you plan to buy). You can calculate the projection image size by dividing the distance between wall and the projector by the throw ratio of the projector. So if your projector is placed 10 feet away from the screen and has a throw ratio of 1.8-2.22, then you can get an image size that ranges between 54 – 66 inches. Ideally, you should be sitting at a distance that is more than twice the width of the image. To make things simpler, many manufacturers offer a distance calculator on their website for various models. Here, you just input a distance or required screen size.

Tip: Some aberrations can be corrected in-projector (keystone for example) but proper placement is the most preferable. If not possible due to placement/room constraints, then you can move on to digital corrections.

Screens are the best way to get the best performance from a projector. A screen will always be smoother than a wall and it will offer higher, more even reflectance. Some screens have gain – they reflect light better, thanks to shiny particles – and this helps in brighter rooms or if your projector is old or has low brightness. Some screens have black borders that add to the perceived contrast – making the image seem better. Finally, screens are also the correct shade of white/grey, solving the problem of a colour cast that some walls may cause. Having said all this, you can use a wall too – there are obvious cost advantages. If you must use a wall, make sure it is as smooth as possible (a plaster of Paris coat helps) and painted in flat white.

There are three main technologies used for projection – DLP, LCD and LED. DLP (Digital Light Processing) uses a chip made of tiny microscopic mirrors and a spinning colour wheel to create an image. DLP projectors deliver sharp images, don"t need any filters, have a better response time as well as 3D capabilities. The effective lamp life of a DLP projector is only 2000-5000 hours and some people see colour ghosting/banding in some scenes. On the other hand, LCD projectors use liquid crystal displays, have no moving parts and thus are generally less expensive. If you are on a budget a single chip LCD projector is ideal while 3-chip LCDs offer better colour saturation, lower noise levels and work better for movies. However, LCDs require constant filter maintenance and output less contrast. The LEDs in LED projectors have a lifespan of over 20,000 hours. They deliver better colours, have lower power consumption and virtually zero maintenance costs. Also, LED projectors are smaller and generate less heat. Do keep in mind that LED projectors have limited brightness compared to LCD or DLP so they are not recommended if your room has a lot of ambient light.

Tip: Some high-end projectors come with a feature called lens-shift. This is a physical rail that adjusts the lens up/down & sideways to move the image around. Obviously, this offers a lot more flexibility with regards to projector placement.

Pico projectors use LEDs as the light source due to which they can be extremely compact in size. Pico projectors can fit in your palm or be integrated into various devices like mobile phones (Samsung Galaxy Beam), tablets (Lenovo Yoga Tab 3), computers, and even digital cameras (Nikon S1000pj). While these projectors do not offer very high resolution or brightness, they are good enough to use in a small, dark room. You can get a 60-inch screen and you can connect multiple devices like smartphones, gaming consoles and laptops. Moreover, the portable size enables manufacturers to add internal storage as well as rechargeable battery in devices that weight less than 200 grams.

Tip: It"s always better to ceiling mount a projector because there are less chances of it being moved once setup. It also places the projector a fair distance away from the viewer so that fan noise and while becomes less audible.

If the projector is not placed perpendicular to the screen, the image is not rectangular – this is a keystone error. Most projectors offer digital keystone correction in the horizontal and vertical planes.

A 3 colour LCD system uses individual LCDs for red, green and blue. The light from each LCD is combined using a prism to create a final image. It usually offers better quality than single chip LCD or DLP designs.

This happens if you"re sitting too close to a projector – fine lines will be seen between the individual pixels on the screen/wall. A screendoor effect usually doesn"t matter if you"re displaying static images (or a presentation) but it affects movies/videos.

If you are new to the world of digital projectors, you won"t have to shop around long before discovering that the terms LCD and DLP refer to two different kinds of projectors. They are in fact two different kinds of microdisplay imaging technology. You might not even know what LCD and DLP are before asking the obvious question "which one is better?"

The answer is simple--neither one is better than the other. They both have advantages over the other, and they both have limitations. Both technologies are much better than they used to be. The purpose of this article is to discuss how they differ today, so you can determine whether the imaging technology itself is a relevant factor in your choice of a projector.

It is important to note there is a third significant light engine technology called LCoS (liquid crystal on silicon). It is developed and marketed by several vendors, most notably Canon, JVC, and Sony. Many excellent projectors have been made with LCoS technology, including several outstanding home theater projectors that can, in the opinion of many observers, surpass the value proposition of both LCD and DLP offerings. The discussion of LCoS technology is beyond the scope of this article, and will be addressed separately in an upcoming article.

You may have already seen the term 3LCD on websites and in projector literature and press releases. Several makers of LCD projectors have adopted 3LCD as a marketing brand name. It is intended to distinguish the specific implementation of LCD technology found in digital projectors from the more common direct view LCD displays found in a wide variety of consumer products. In LCD projectors there are always three LCD panels, and they are always light transmissive devices rather than reflective or direct view displays. Within the projector industry, there is no technical difference between 3LCD and LCD, and the terms can be used interchangeably.

Well, the answer to this question depends on your definition of the word "lead." As of this writing, DLP technology has a significant lead in terms of the number of models currently in production. As of this date, July 28, 2009, our database lists 704 different DLP-based models in production, as compared to 430 LCD models. Thus, DLP holds a commanding lead in the number and variety of models being produced.

However, this is not the whole story. Many of the best selling projectors these days are LCD models. As an example, at the moment, six of the Top 10 Most Popular 1080p home theater projectors on this site are LCD"s, two are DLP and two are LCoS. In fact, despite the clear advantage DLP has in the number of models in production, Pacific Media Associates reports that LCD projectors held a 51% market share by unit volume in 2008. Clearly both technologies have a huge market presence, and neither one is about to emerge as the dominant player.

LCD (liquid crystal display) projectors contain three separate LCD glass panels, one each for the red, green, and blue components of the video signal. Each LCD panel contains thousands (or millions) of liquid crystals that can be aligned in either open, closed, or partially closed positions to allow light to pass through. Each liquid crystal behaves in essence like a shutter or blind, and each represents a single pixel ("picture element"). As red, green, and blue light passes through the respective LCD panels, the liquid crystals open and close based on how much of each color is needed for that pixel at that moment in time. This activity modulates the light and produces the image that is projected onto the screen.

DLP ("Digital Light Processing") is a proprietary technology developed by Texas Instruments. It works quite differently than LCD. Instead of having glass panels through which light is passed, the DLP chip is a reflective surface made up of thousands (or millions) of tiny mirrors. Each mirror represents a single pixel.

In a DLP projector, light from the projector"s lamp is directed onto the surface of the DLP chip. The mirrors tilt back and forth, directing light either into the lens path to turn the pixel on, or away from the lens path to turn it off.

In the most expensive DLP projectors, there are three separate DLP chips, one each for the red, green, and blue channels. However, in most DLP projectors under $10,000 there is only one chip. To define color, a color wheel is used that contains (at minimum) a red, green, and blue filter. This wheel spins in the light path between the lamp and the DLP chip and alternates the color of the light hitting the chip from red to green to blue. The mirrors tilt away from or into the lens path based upon how much of each color is required for each pixel at any given moment in time. This activity modulates the light and produces the image that is projected onto the screen.

(Note: In addition to red, green, and blue filters, most color wheels contain other segments as well. A "white" or clear filter used to boost brightness is common in business/commercial projectors, and many color wheels have filters for colors other than the primaries, such as dark green, cyan, magenta, or yellow.)

Sealed imaging chip. Most DLP projectors have sealed DLP chips that eliminate the possibility of a dust particle alighting on the imaging plane, which could create a dust spot on the projected image. LCD projectors do not have sealed panels, and the possibility of getting a dust spot exists. This is especially true when air filters are not cleaned periodically as per operator manual instructions.

Filter-free. DLP projectors that have sealed DLP chips can operate without air filters. Thus maintenance is reduced since there is no need to periodically clean or replace filters. Some vendors represent their DLP products as maintenance free, other than the occasional lamp change and dusting of the case and lens. Others don"t go quite that far, and recommend a periodic vacuuming of the air vents to limit the amount of dust getting into the unit. The vast majority of DLP projectors on the market do not have air filters, but some of the most expensive high performance 3-chip DLP models do, as do a few earlier generation DLP models that may still be in use.

Whether filter-free design is a true advantage to the user is a matter of competitive debate and controversy. In most DLP projectors, components other than the imaging chip itself are not sealed and can be adversely affected by a build-up of dust. In particular, dust on the color wheel may affect color and image quality. Dust particles can burn or melt when coming into contact with the lamp surface, thereby accelerating the degradation of lumen output over the life of the lamp. The degree to which a filter-free projector might be adversely affected depends on how much dust there is in the operating environment. Texas Instruments maintains that the amount of dust found in a normal room environment will not adversely affect the operation of a filter-free projector. Those who advocate the use of filters maintain that air filters will prevent an accelerated degradation of the lamp"s lumen output, even in normal room conditions.

Recognizing dust as a potential problem, Mitsubishi has taken extra steps to combat dust contamination in their latest filter-free DLP projectors, the XD3200 and WD3300. They have sealed the color wheel to prevent dust from reaching it. They have also made design improvements to the light pipe and airflow channels which reduce the amount of dust that can reach the lamp. These changes are intended to help maintain the lamp"s lumen output potential over its lifespan.

Those who advocate using air filters on projectors maintain that dust is never good inside a projector, and that the user is better off with a filtered design that prevents dust from entering the projector to begin with. All LCD projectors use air filters, as do some of the higher end 3-chip DLP models from vendors such as Runco and Digital Projection.

Those who support filter-free designs point out that many users of filtered projectors do not follow recommendations for cleaning or replacing air filters. If an air filter gets clogged over time, it can inhibit airflow, increase internal operating temperatures, and adversely affect the life of the LCD panels.

No convergence problems. All projectors using three imaging devices, whether they are LCD, DLP, or LCoS, must have all three devices aligned perfectly so that the red, green, and blue information for each pixel is in convergence. Over time, these three device systems can slip out of alignment. On occasion they can come out of the box, brand new, with slight convergence errors. Convergence errors can soften the projector"s image and create color artifacts where there shouldn"t be any.

The single-chip DLP design has a unique advantage over all three-chip or three-panel systems: since there is only one imaging chip, convergence problems don"t exist. There is simply nothing to go out of alignment.

Contrast advantages. Most business class DLP projectors (those intended for portable presentation or conference room use) have much higher Full On/Off contrast ratings than comparably priced LCD models. ANSI contrast figures are rarely published in the projector industry, but our measurements indicate DLP projectors usually have an edge over the LCD competition in ANSI contrast as well. However, with the introduction of inorganic LCD panels that are now used in most LCD 1080p home theater products, DLP"s traditional advantage in contrast within the home theater market niche has been neutralized to a large extent.

No image persistence. If one displays a static image for an extended period of time, an LCD projector with organic LCD panels may have a tendency to retain a subtle ghost of that image even after the subject matter is switched to another image. This does not occur on a DLP projector. Nor does it occur on LCD projectors that use inorganic panels.

Some of the advertising hyperbole has blown the seriousness of this issue out of proportion. Anti-LCD ads have claimed that LCD projectors are subject to "burn-in." Strictly speaking, this is not really true. Burn-in, in traditional usage, refers to permanent damage that can be suffered by CRT or plasma phosphor-based displays. Once a static image has been etched into a phosphor display through long term exposure, it cannot be removed. This is a different phenomenon than we see on LCDs. On organic LCD displays, when image persistence occurs, it is temporary and can normally be erased by displaying a white screen for a period of time.

Nevertheless, the point is that image persistence does not occur on either DLP projectors or inorganic LCD projectors. So on these products there is never any need to take steps to erase a persisting image.

No degradation of image quality over time. There is usually no degradation of image quality on DLP projectors when used over long periods of time, other than that which might result from excessive internal dust build-up. But in any event, the DLP chips themselves will not degrade. Conversely, LCD panels and polarizers can degrade with time, causing color shifts, unevenness of illumination, and reduction of contrast. The degree to which LCD degradation is a problem on current products is somewhat of a mystery since those who know the most about it (the LCD manufacturers) don"t discuss it publicly. This issue will be discussed further below.

Somewhat less pixelation/screendoor effect on low resolution products. One of the historical advantages of DLP over LCD has been a reduced level of pixelation in the image. Pixels tend to have sharper definition on an LCD projector, and this can produce a more visible pixel structure in the image. This is often called the screendoor effect, since the picture on low resolution projectors can look like it is being viewed through a screendoor.

However, the differences between LCD and DLP in this regard are not as great as they used to be for two reasons. First, LCD makers have achieved smaller interpixel gaps, making the screendoor effect much less visible. Second, the average native resolution of projectors being sold today has increased dramatically over what it was several years ago. With increases in resolution come smaller pixels and a less noticeable pixelation across the board. Nevertheless, on low resolution products like SVGA and even standard XGA, DLP projectors still have an advantage in manifesting somewhat less visible pixel structure than LCD projectors. (Note: There is a disadvantage to having less distinct pixel structure, which is reduced image sharpness. We will discuss this further below.)

DLP leads in miniaturization. The single-chip light engine affords the opportunity for extreme miniaturization that LCD cannot quite match. At the moment there are 15 DLP projectors on the market that weigh less than 3 lbs and put out more than 1000 lumens. By comparison, the lightest 3LCD projector on the market weighs 3.5 lbs and most are 4 lbs or more.

The rainbows occur because of the sequential color updating from the wheel or LED. As the color wheel spins or the LEDs change, the image on the screen is either red, green, or blue at any given instant in time. The technology relies upon your eyes not being able to detect the changes from one to the other. However, when your eye moves rapidly in response to some movement in the picture, you can get a red, green, and blue update on three different points on your retina, thus producing the impression of a rainbow. Not everyone perceives rainbows the same way. Many people have less sensitive eyes and cannot detect rainbow artifacts at all. Others see them quite readily. There is no way to know whether you are among those who can or cannot see them except by watching a DLP projector yourself.

Since LCD projectors and 3-chip DLP projectors always deliver a constant red, green, and blue image simultaneously, they do not create rainbow artifacts.

On DLP projectors with color wheels, rainbow artifacts are reduced by increasing the speed of the wheel. The first generation DLP projectors incorporated a color wheel that rotated sixty times per second, or 3600 RPM. With one red, green, and blue filter in the color wheel, updates on each color happened 60 times per second. This rotation speed in the first generation products was known as a "1x" rotation speed. In second-generation DLP products, the color wheel rotation speed was doubled to 2x, or 7200 RPM. The doubling of the color refresh rate reduced the time between color updates, and so reduced the visibility of rainbow artifacts for most people. But a 2x rotation speed was still not fast enough for products to be used in home theater and video applications.

Today, some DLP projectors being built for the home theater market use a color wheel containing two sets of red, green, and blue filters. This wheel still spins at 7200 RPM, but because red, green, and blue are refreshed twice in every rotation rather than once, the industry refers to this as a 4x rotation speed. And by increasing the physical rotation speed beyond 7200 RPM, some projectors now have 5x or 6x speed wheels. For the large majority of users, the 5x and 6x speed wheels in most current home theater models have reduced rainbow artifacts in video display to the point where they are of little or no concern.

However, most DLP projectors built for commercial/presentation use still use 2x speed wheels because they are less expensive. This is perfectly fine if the presentation matter is static charts, graphics, photography, or anything that does not stimulate rapid eye movement. We do not recommend DLP projectors with 2x speed wheels to buyers for whom video display or part time home theater are important intended uses.

Color saturation/color brightness. Some DLP projectors have excellent color saturation, and some are exceptionally poor. This is related more to the vendor"s implementation than anything inherent in the technology itself. Advocates of 3LCD technology have been quite vocal about the lack of color brightness on single-chip DLP products, particularly those that have white segments in the color wheel. This phenomenon is worth commenting on.

When a color wheel has a white (clear) segment, the lumen output of the projector is increased dramatically, and the ANSI lumen rating skyrockets. Most business class DLP products have white segments in the wheel to boost the all-important lumen rating. Conversely, most DLP projectors built for home theater have no white segments because they can compromise color saturation and the overall balance of the video image. Moreover, the lumen rating is not a big driving factor in the sale of home theater projectors.

When you use a light meter to measure the brightness of red, green, and blue on an LCD projector, the sum of the values usually adds up to the brightness reading you get for white. This makes sense because on an LCD projector, white is created by turning the red, green, and blue channels all fully on. But on a DLP projector, this is often not the case. Due to the presence of a white segment in the wheel, the white reading can be as much as double the sum of the brightness readings for red, green, and blue. In other words, if an LCD projector measures 2000 lumens of white light, you will also get 2000 lumens of color light out of it. If a DLP projector measures 2000 lumens of white, you might get only 1000 lumens of actual color light from it, the rest being white light.

Because of this, proponents of 3LCD technology have been lobbying for color brightness specs to be included along with ANSI lumen specs on the industry"s specification sheets, and support for this has been building in the industry. In the spec wars, quite clearly this would be one metric on which LCD has a commanding advantage over DLP. Not surprisingly, Epson and Sony have already begun to publish color brightness specs on their LCD projectors to drive home the point. The color spec is always the same as the ANSI lumen rating, and the specs will read, as an example, "2600 lumens color light output, 2600 lumens white light output."

As a rule, DLP projectors with a white segment in the wheel do not look very appealing when measured for color brightness. The color reading always fall short of the white reading, and sometimes it falls short by 50% or more. This is especially true when the color wheel contains the basic red, green, blue, and white filters only. Many DLP projectors have complementary color filters such as cyan, magenta, and yellow. In this situation the color brightness measurements become more problematic. Thus we can understand why Texas Instruments and the DLP projector vendors have little interest in publishing color brightness specifications.

From a practical perspective, we have mixed feelings about all of this. Clearly, the 3LCD camp is correct that the traditional ANSI lumen spec does not tell the whole story. But neither does the color brightness spec. To be sure, the color on some DLP projectors looks dull and anemic next to some LCD models of the same lumen rating. Ironically, this can be particularly true when the "BrilliantColor" feature is enabled. Though BrilliantColor boosts the brightness of the image, it can substantially reduce color saturation in the process. It is peculiar that in order to get the richest and most saturated color from many DLP projectors, one needs to turn BrilliantColor off. (This is not universally true of all DLP projectors with BrilliantColor, since the BrilliantColor system can behave quite differently based on how it is implemented by the vendor.)

Oddly enough, on some DLP models with white segments in the wheel, even those on which color brightness falls far short of white, we see a rich, vibrant color that can easily match an LCD projector in the same price and lumen class. One reason is that the color filter configuration of the wheel has a lot to do with the end results. Another reason is that, though the DLP"s color brightness may fall short of white, the effect of the DLP"s inherent contrast advantage helps to compensate for it. That compensating effect cannot be quantified in a spec. Even when color brightness falls very far short, the picture sometimes does not end up looking much dimmer at all when put side by side with an LCD projector of the same white light output.

When a DLP projector"s color vibrancy looks poor next to a comparably priced and spec"d LCD projector, it is due to a variety of design and product cost decisions made by the vendor, and not anything inherent to DLP technology per se. DLP can look truly spectacular or downright dismal depending on what is done with it. With so many variables in play, the specs can"t tell the whole story, even if a color brightness spec were added to the mix. The publication of color brightness specs would be interesting, and would certainly draw attention to a noteworthy technical difference between LCD and DLP. But it is not conclusive information that would help an astute buyer sort out which model to buy.

Dithering artifacts. At any moment in time, each mirror position on a DLP chip is either fully on to render maximum brightness, or fully off to render black. There is no way a DLP mirror can be "partially on" to represent gray, like an LCD liquid crystal can. Therefore, the way the DLP chip renders gray is to flip the mirrors on and off very rapidly, such that they are on just enough of the time for the eye to average the "on"s and off"s" to a desired level of perceived brightness. This approach to rendering grays is called dithering. It works well enough for rendering gray values, but it can produce some visible instability in solid fields, mostly dark areas, referred to as dithering artifacts. It looks like digital noise, but it is a separate type of artifact caused by DLP technology itself, and not by the signal.

Dithering artifacts do not occur on LCD products because there is no dithering used to achieve varying levels of gray. The liquid crystals can be either fully open, or closed, or partially opened at intermediate positions to achieve the desired level of light transmission--again, similar in concept to shutters on a window.

Restricted compatibility with zoom lenses and lens shift. Due to the nature of DLP light engine mechanics, it is difficult for vendors to incorporate long zoom lenses or extended range lens shift features into a DLP projector. These limitations are not relevant in mobile presentation projectors since the primary design objective is small physical size, so none of them have big zooms or lens shift anyway. But in the home theater market in particular, LCD vendors have captured significant market share in part due to their ability to incorporate long 2.0x zoom lenses and extensive lens shift capability into LCD projectors. This makes it much easier for the consumer to install the projector anywhere they want, which is quite frequently on a rear shelf in the room. Due to lens restrictions on DLP projectors it is rare to be able to install a DLP model on a rear shelf.

Many of the advantages and limitations of 3LCD have already been touched on above within the context of the DLP discussion. However, there are several advantages of LCD not yet discussed, and some of the issues already noted warrant a recap and/or further expansion. The following are the key benefits of LCD technology:

Better price/performance in HT products. The primary key to the success of LCD products in the home theater market is their tremendous price advantage. In the 1080p niche in particular, LCD products deliver outstanding image quality performance for the money. Moreover, they are generally loaded with extra features that don"t appear on DLP models in the same price range, if they are offered on any DLP model at all.

The price advantage of LCD over DLP is most obvious in consumer/home theater products. There is no similar disparity in pricing on commercial products built for mobile presentation and conference room use. One reason is that DLP makers can use the cheaper 2x speed wheels on most business products, whereas it is mandatory to have high speed color wheels and the faster electronics associated with them on products designed for home theater.

Higher contrast in HT products. Many LCD projectors built for home theater have achieved better overall contrast performance and deeper black levels than DLP models. This is specifically the case on LCD models using inorganic LCD panels and auto iris technology. Inorganic panels are more expensive to produce, so they are not used in cheaper, commercial grade business projectors. They achieve higher contrast due in part to the fact that the resting position of the liquid crystal is closed (i.e., black), and voltage is required to open it. This is the opposite of traditional organic LCDs wherein the resting position is open (maximum light transmission), and voltage is required to close it. The inherent contrast advantage of inorganic panels has made LCD substantially more competitive in the home theater marketplace. ANSI contrast in particular has seen significant improvement. In our measurements, LCD projectors with organic panels typically run in the range of 250:1 ANSI contrast, whereas the models with inorganic panels have been reaching performance levels of 400:1 to 450:1.

3LCD vendors have been aggressive in developing effective auto iris systems which contribute an incremental perceived contrast advantage on screen. There is no technical restriction that we know of that would prohibit DLP vendors from doing the same thing. But it would add further cost to DLP projectors that are already at an apparent cost disadvantage relative to LCD in the home theater market. There is also a perception among vendors that DLP contrast, while not leading edge, is sufficient, so enhancement via auto iris is not vital. Thus, most DLP vendors have been slow to incorporate auto iris systems on DLP projectors being marketed for home theater.

Fewer artifacts/greater image stability. As noted previously, dithering artifacts and rainbow artifacts are unique to single-chip DLP projectors. Since these artifacts do not exist on LCD products, it is not unusual to perceive a more stable video image on an LCD projector when viewed side by side with a DLP counterpart in a similar price and performance class. The LCD"s video image can look cleaner and more free of noise.

Sharper image with data display. Since LCD pixel structure is more sharply defined that DLP pixel structure, it tends to render a sharper image. This is most noticeable in lower resolution business products (SVGA and XGA), and specifically with data display. It is in these resolutions that LCD"s screendoor effect is somewhat more visible in a video image, but the advantage is that the sharper pixel definition can produce a sharper display of data. By comparison, a DLP projector in SVGA and XGA resolution can look a bit soft when displaying data images.

Greater installation flexibility in HT products. LCD projectors built for home theater often feature 2.0x zoom lenses and extensive vertical and horizontal lens shift. This makes them easy to install just about anywhere. By comparison, DLP projectors usually have short zooms with little or no lens shift. Fixed throw angles limit the projection geometry, and often dictate where a DLP projector must be placed in order to accommodate a given screen size and location.

For the DIY home theater enthusiast on a budget, the lens flexibility of LCD models has great appeal. For the fact is, most DLP projectors need to be ceiling mounted, and most LCD projectors don"t. Thus they save the extra cost of a ceiling mount and long run video cables. They also eliminate the prospect of having to run cables through walls and ceiling, or living with an unsightly track of cables across the ceiling.

Better light efficiency, less power usage. LCD technology is inherently more light efficient. For the most part LCD projectors use lower wattage lamps to produce the same image brightness that you"d get from DLP. This is most noticeable when comparing LCD projectors to DLP projectors that have no white segment in the color wheel. As an example, compare two currently popular 1080p home theater projectors--the Panasonic AE3000 LCD projector uses a 165-watt lamp to produce 1600 ANSI lumens. Meanwhile, the Sharp Z15000 DLP projector needs a 250-watt lamp to get the same 1600 lumens. That can make a noticeable difference in power consumption. It can also make a difference in the amount of heat being generated by the projector"s exhaust in the viewing room.

Unknown lifespan of LCD panels. Given enough prolonged exposure to high intensity UV light and extreme heat, the organic compounds used in most LCD panels are expected to degrade over long periods of time. This degradation can lead to a discoloration of the image and a reduction in contrast. The only way to fix it is to replace the damaged LCD panel, which is typically a cost-prohibitive proposition. You are normally better off buying a new projector.

The big question of course is how long the panels will last. There is no good data on this subject that has been compiled by an independent lab and published for general consumption. LCD vendors do not typically acknowledge LCD degradation can occur, so they don"t make any representations about expected life. In general, most LCD vendors maintain that to the degree LCD panels might be subject to eventual degradation, it will be beyond the practical life of the product.

One trusted and very experienced industry source who develops products using both LCD and DLP technology believes that LCD panels have a lifespan in the range of 4,000 to 10,000 hours, with the lifespan depending on how bright the projector is--the brightest LCD light cannons will produce the most stress on the panels resulting in quicker degradation. Low brightness models such as those made for home theater will produce the least stress, and are expected to last longer.

Texas Instruments has performed several tests on LCD lifespan over the past seven years. Based on these tests, they believe that LCD panels will degrade faster than the LCD vendors are willing to admit, and certainly more quickly than the 4000 hours just quoted. The 3LCD camp"s response is that TI"s tests have been performed by running LCD projectors continuously 24 hours a day, 7 days a week, for several months straight. According to 3LCD and Epson, since the projectors used in TI"s lab tests were never designed for a continuous operation high-stress duty cycle, the results are not indicative of what the typical user would experience.

The introduction of inorganic LCD panels is an important new development that is germane to this issue. Inorganic LCD panels, in theory, should not be subject to the same degradation patterns as organic LCDs, simply because the organic compounds that fail under intense heat and UV light are not present in inorganic LCDs. However, the LCD camp will not confirm or deny any anticipated differences in panel life because as a matter of policy they do not discuss the issue at all. Texas Instruments has not commented on the expected lifespan of inorganic LCDs either.

Lower contrast ratings in business products. Most commercial and education LCD projectors are made with the relatively inexpensive organic LCDs and no auto-iris. Contrast ratings on these models typically run in the 400:1 to 700:1 range. Meanwhile, DLP projectors in the same resolution, lumen, and price class can often be rated at 2000:1 or higher.

In reality, this constitutes more of a marketing disadvantage than a technical one. In most business/commercial and classroom settings, projection display is done with room lights on. With moderate ambient light--enough for children in a classroom to take notes for example--a projector"s contrast rating is largely irrelevant. Actual contrast on screen with moderate ambient light is typically in the range of 50:1 regardless of the theoretical contrast potential of the projector. But for buyers who are not aware of the huge impact of ambient light on contrast ratios, the apparent advantage of DLP over LCD in contrast ratings can appear to be more significant than it really is.

Susceptible to dust spots. Since LCD light engines are not sealed, it is possible for dust particles to alight on the LCD panels, thereby creating a dull, indistinct spot on the projected image. This usually causes little distraction when displaying static images such as data or photographs. But in full motion video, seeing a stationary element in a moving picture can be extremely distracting.

When dust lands on an LCD in the red or blue channel it is rarely visible enough to create a distraction. But when it occurs in the green channel it can become quite visible. Some vendors have provided methods by which the user can remove the dust without having to send the unit in for cleaning. Sanyo"s home theater models come with a hand pump that will blow a jet of air across the panels, but since we"ve never seen a dust spot on a Sanyo projector, we"ve never been able to test the device. Other than this sort of solution, packing the projector up and sending it to a maintenance depot for cleaning is the method of last resort for getting the projector back into serviceable shape.

LCD makers claim that today"s air filter systems are superior than those of the past, and that dust contamination is highly unusual if the filters are cleaned and replaced as per normal maintenance instructions. Most LCD vendors cover dust removal under warranty, which is a good reason to buy LCD projectors with extended warranties.

When we review projectors, we have no way to assess the actual risk to the user of dust contamination on any particular model. We can say that it is rare for us to notice dust spots on LCD projectors that we get in for review, or on units that we keep in operation for ongoing reference purposes. However, it is easy for users to forget to clean filters since under normal usage vendors recommend this be done every two months or so. When filters are left unattended, the user increases the risk that dust will eventually find its way into the projector.

The fight for market share between 3LCD and DLP continues at a fevered pitch. It is a fascinating thing to watch as vendors of both technologies continue to innovate to stay a step ahead of the competition. Picture quality in digital projectors has improved dramatically over the past decade with significant increases in contrast, resolution, and color performance. Prices have dropped like a rock, and high quality projection systems that once were within financial reach of wealthy consumers or businesses who really needed them, are now within the budgets of mass consumers. Thus the consumer is the ultimate beneficiary of the intense competitive struggle between the DLP and 3LCD technologies.

As we"ve tried to make clear in this article, both DLP and 3LCD have key advantages over the other. They also both have limitations that the buyer should be aware of. But in the end, we see better image quality performance today from both LCD and DLP than we"ve ever seen in the past. And it just keeps getting better.

Based on my experience with LCD projectors, my rule of thumb for organic LCD panel degradation is to assume that the projector will be unusable by the time you finish the second bulb. So if the bulb is rated at 3000 hours, I would assume a useful life of the projector at no more than 6000 hours. If you use such an organic LCD projector as a TV replacement you will likely have to replace it every few years.

Owner of 14 projectors I have used both LCD and DLP projectors in a 24 hour a day operation with static images on the screen for the most part. I have found DLP projectors out perform LCD in many areas. I have middle of the road $5k DLP projectors and one high end >$12k all of which have lasted years longer than my LCD projectors all of which were >$10k. I actually replaced LCD panels regularly in one manufacturers and the burn out was quick. The other projector was cost prohibitive to replace. I will go with DLP unless the unit is not used much.

If an LCD panel can produce for example 2000 Lumens at white (all 3 panels on full), then how can it produce 2000 Color Lumens? Like if it"s a Red color being displayed, it wouldn" t use all 3 panels on full thus the Lumen output would have to be greatly reduced. It would be primarily the red panel on and the other would be off or greatly reduced.

Is there any anecdotal evidence that inorganic LCD panels do last longer? I"d be particularly interested in hearing from someone like Richard who appears to really put projectors through their paces.

I have to wonder if the fact that TI has not published the results of a study on inorganic LCD means that the panel life is long enough to be a non-issue. This isn"t evidence in itself, but it is one plausible explanation.

I"ve had a DLP projector in the past and was relatively happy with it. I"ve been considering LCD, mainly because of the placement flexibility of zoom & lens shift, but things like dust blobs and panel life have made it difficult to pull the trigger on those purchases.

It would have been interesting to hear details on why DLP cannot have the zoom and lens shift flexibility of LCD. I"ve heard the lens shift is because of the issue of bouncing of the light off the DLP chip through the color wheel and then through the lens so that in order to shift the lens you"d have to move the entire light path. I"ve not heard any reasoning for the lack of zoom found on DLP.

Wish the LCoS comparison had been included with this article, but will wait patiently for it and hopefully it will compare and contrast against DLP/LCD and not simply be a stand alone tech summary.

What a great article! Very fair and balanced- unlike some news channels! I have had a Panasonic AE700 LCD projector for 5 years now and have had no dust blobs or PQ degradation whatosever. I am still using the original bulb, and the picture is still stunning. I love the 2X zoom lens and wide-range lens shift which lets me mount the projector out of sight on a rear shelf. I just would not take the risk of seeing the DLP artifacts, so my next projector will definately be 3LCD.

This is the first I"ve heard that dust deposits lead to the lamp becoming dim. I find this a little hard to believe. If it were true then LCD projectors with dust filters would have substantially longer bulb lives than filterless DLP projectors. I don"t think this is true.

Also I used to periodically clean inside my first projector an InFocus X-1. The color wheel got grayed out by deposits not the bulb. Wiping off the color wheel greatly improved the image brightness. I believe that this deposit was from plastic volatiles that had settled on the relatively cool color wheel. I don"t think it was melted dust. Am I wrong?

Lastly, why are there no single chip LCoS projectors? LCoS is refelective like DLP? It should I would have thought been a good candidate for for a one chip/color wheel design. Maybe its the speed question?

When the Panasonic PT-AE700U 3LCD projector was the hot new player on the price/performance curve I installed two of them. One was in a friend’s dedicated home theater and the second was in my family’s home theater/living room.

The AE700U in my home developed severe blue discoloration in the lower left side of the image due to the organic LCD panels. One can find many users so afflicted on the forums. Of course this did not come up when the AE700 was the hot new piece because no one had the hours on it necessary to cook the panels.

I believe one of these samples is still looking good and the other is barely watchable because of how they are/were used. In the dedicated home theater my friend’s unit was on for 1-3 hours at a time to watch a movie or two then shut down. In our combined home theater/living room the projector was used for both movies and general TV watching. Its death was hastened when my son hurt his foot and spent the all summer long recovery process watching hours of movies, games, and cable TV. It was after this stint of being on 8-16 hours a day I noticed the beginnings of the blue discoloration.

When the second bulb in our AE700 was used up I could not bring myself to spend $375 to watch 1/3 blue HDTV. As a stopgap I purchased a factory refurbished 1024x768 DLP projector for less than the cost of a new bulb for the AE700. The picture is not bad, I can see it is not as good as the new AE700 was or the 1080P Toshiba flat panel we have in the den, but the family thinks it looks good. My hope is by the time the XGA DLP projector needs a new bulb the market has an affordable 1080P inorganic 3LCD or DLP projector using LED lighting.

I find 3LCD to be a flat technology. It"s gone about as far as it can go in terms of applications. Can 3LCD project a 3D image from a single projector like the new DLP units can? With all the new movies coming out in 3D from Hollywood, I want to make sure I"m going to get a HT projection system that can show movies the way they were intended to be seen.

For me DLP is the only way to go. You don"t have to worry about color decay and cleaning filters. When I change the lamp on my DLP projector, the image looks just like the image when I bought it 3 years ago.

As someone that both rents out projectors and easily gets DLP rainbows + headaches, I refuse to look at DLP ever again- it hurt my head besides ruining the content.

I also would not want to subject any of the audience to possible artifacts that I may not even see myself- even 1% of the paying audience is unacceptable. Therefore, while newer DLP based projectors may reduce or eliminate the problem for a larger % of people, I can"t take that risk!

this Adjusting the LED´s will make the DLP/LED projectors superior in contrast (already demoed prototypes with over 100000:1 ratio without an Iris). and since they have been superior in sharpness (atleast i think so