What Is The Difference Between LCD, DLP & LCoS Projectors & Which Is Best?

I don't think this guy really cares too much about the projector type. But we do, so read on!

Are you looking at buying a new projector but are confused by the different types out there?

If so, this article is for you, I explain in clear terms what the differences are between LCD, DLP and LCOS projectors, which should help you to choose the right one for your requirements.

Let's get started!

Why are there different types of projector?

The different types of projector out there all try to do one thing and that is reproduce the image as accurately as possible. They do that in different ways so there are various pros and cons to each type of projector. You have to weigh up what is important to you and make your decision based on that. Here are the differences between them.

Watch this thing doesn't fly off!

LCD projectors

LCD, which stands for Liquid Crystal Display, projectors are pretty versatile. They work by shining the lamp through three separate coloured panels, each of which can open or close the individual pixels to let light through or block it. This makes up the image.

How the LCD projector makes an image isn't really too important, what is important is what it is good at and what it is bad at.


This type of projector usually has lens shift. If you can't place your projector perfectly central to the screen and at the right height (not always possible), then lens shift is very useful as it allows you to move the image vertically and horizontally. This can mean that you can put the projector to one side of your sofa for example and still be able to project the image onto the screen, or maybe on the coffee table if you are crazy and don't mind people kicking the thing across the room when they get up for a drink. Either way, you have a lot more placement options and versatility with an LCD projector than some other projectors, so this is a big plus.

LCD projectors also usually have zoom. This allows you to expand or contract the image to fit the screen, so you don't have to have the projector at a specific distance from the screen. Again this can be useful if you are limited on ceiling mount placement.

LCD projectors tend to have a sharp image, often sharper than equivalent DLP. This doesn't mean that a DLP will look blurry in isolation, but if you have a side by side comparison, then you can find that LCD are a bit sharper.

An exaggarated example of screendoor effect, where individual pixels are visible

LCD also has another advantage, they are among the quietest projectors out there. This may or may not be an issue for you, personally I think fan noise on a projector is a pretty big deal, so the quieter the better.

This type of projector doesn't have the potential for rainbow effect, which is explained below.


LCD projectors can suffer from the 'screen door effect', this is where the individual pixels on screen are visible. This isn't usually a problem if you're sitting far enough back, but as some people like to have a large screen and sometimes don't have the largest rooms, then this is definitely something to bear in mind.

LCD projectors also aren't known for having the best blacks or most vivid colours. Of course there are some very good LCD projectors out there, but typically at the equivalent price range, then DLP tend to beat them in this regard. The contrast ratio on LCD projectors, is usually lower than equivalent model DLP.

Contrast ratio? What's that then?

Contrast ratio is the ratio between black and white. If there is a high contrast ratio, then there is a greater difference between the two. If the contrast ratio is low, then you will tend to find that blacks are more grey than black and whites aren't as vivid as they could be. There are various ways of measuring this, so trusting manufacturers specs isn't always a good way of comparing this, but keep your eyes open when reading reviews for projectors that have a high contrast ratio.

Of course the contrast ratio of a projector makes little difference if you're not using the projector in a dark room. If you have gone to the effort of blacking your viewing room out, then a high contrast ratio projector will look better than a low ratio projector. If the room is fairly well lit, then there will be little difference between the two.

This is an example of low and high contrast ratio, low is on the left, high on the right.

DLP's are great if you ever want to start juggling projectors

DLP projectors

DLP projectors work a little differently to LCD, these mirrors use a matrix of mirrors and either one or multiple colour wheels to put the image on screen.

Once again the method the projector uses to display the image is not really too important, so here are the pros and cons of this type of projector.


DLP projectors tend to have better blacks and more vivid colours than LCP projectors. There is an expression that projector buffs use to describe the image, which is how much the image 'pops', or jumps out of the screen at you. DLP projectors generally tend to beat equvalently priced LCD projectors at this.

They also don't suffer from the screendoor effect mentioned and demonstrated above. This can be a big deal, or not depending on how large a screen you're using and how close you're sitting to it. In my personal experience with an 80" screen from about 10 feet away, screendoor effect was noticeable when I had an LCD projector, although it wasn't pronounced enough to really affect my experience. However changing to a DLP and eliminating it was nice.

DLP projectors also tend to have higher contrast ratios than LCD projectors. This can make a nice difference to the picture if your room is light controlled.


You don't get something for nothing and if you do decide to go for a DLP projector over an LCD, then you will likely have to contend with a louder fan. Of course you'll need to check the spec sheet for each individual projector, but as an example two currently available and well regarded projectors, the Panasonic PT-AE8000, which is LCD and the Mitsubishi HC7800D, which is DLP have a fan noise of 22db and 31db respectively.

I use a projector which has a fan noise of 32db, ceiling mounted directly above my head and the fan noise is certainly audible and some could say a little irritating. Of course once the soundtrack to the film starts, then usually I forget about the fan noise, but eliminating it would make for a better experience in my opinion, so this another factor to bear in mind when considering LCD vs DLP.

The other thing you will have to bear in mind is that often DLP has a slightly softer image than LCD. This can make it more filmlike and not really make an impact on films where maximum sharpness isn't required, but if you're using your projector as a monitor, sharpness can be a factor.

Of course you also have to bear in mind that DLP projectors don't usually have lens shift, so you will need to check if you are going to go for one that you can mount it central to the screen and at the correct distance. If ceiling mounting, this isn't usually too much of a problem, but DLP are certainly not as accommodating as LCD in this regard.

How nice. In a field anyway, not so great if it's on your screen!

What about this rainbow effect I've been reading about?

Rainbow effect is something that some people see with DLP projectors. This is because of the way the picture is created, people that are affected tend to see flashes of colour when moving their heads quickly around while looking at the screen.

This could potentially be a problem if you do see the rainbow effect. However this isn't as big a problem as it sound in my experience, I've had a DLP projector for years now and have had many people in my home cinema for demos or just friends and relations there to watch films. I've never mentioned rainbow effect to any of them and not one of them have ever said they have ever seen it. I think it is something that you can learn to see and my advice is, don't try!

The sensible thing to do would be to have a quick look at a DLP projector before buying, just to check that you don't suffer from rainbow effect as of course everyone is different and you may be one of the unlucky ones. I wouldn't worry too much about it though as I think it is actually pretty rare.

I thought I'd throw in a horribly complicated diagram just to get your brain working

So what about LCOS?

LCOS (Liquid Crystal on Silicon) projectors are a form of projector that sits somewhere between LCD and DLP. LCD uses liquid crystal for each pixel allowing light through or not. DLP uses tiny mirrors in the path of the lens, which tilt to alter the image. LCOS uses reflective liquid crystals.

Once again, the way it does it is quite complicated and not really relevant, as the way it works in the home is more important.


LCOS projectors produce a very smooth and accurate image. The quality of these projectors is great and they don't suffer from screendoor effect, while offering very acccurate colour reproduction.

They are often very bright, which can be a good thing if you haven't got a completely blacked out room.


Fairly major con for this type of projector is that they are usually very expensive. If you can afford one, great, but if you don't have 1000's to spend, one of these may not be right for you. There aren't many on the market as they are more specialised really, this may change in the future, but that is the way it is at the moment so you will have more support if you do decide to go for one of the more popular types.

The other cons to these projectors is that the contrast ratio is not as good as equivalently priced LCD / DLP projectors. What you gain in colour reproduction, you lose in contrast ratio.

The fan noise on these projectors isn't brilliant either. You can potentially be looking at mid 30s db, which is on the high side.

The quality of these projectors is good, so certainly don't write them off, you may find that if you have the cash and the space, one of these would be perfect for your requirements.

My conclusion - which projector type is the best?

Well I hope this article was useful. It isn't always clearcut when looking at choosing a projector. You have to bear in mind several factors and weigh up which are the most important factors for you. I have had LCD and DLP projectors and from my personal perspective I prefer the image from the DLP that I have at the moment over the LCD that it replaced.

But when it comes to changing my projector that doesn't mean I'm going to definitely go for another DLP, I may do, but I am going to weigh up the fan noise and placement issues with DLP carefully before coming to a decision, based on what is the best projector around at the time. There isn't a clearcut winner here, all of the projector types out there have pros and cons, only you can really decide which will suit you best.

Hopefully you are now a little more informed about what you have to bear in mind when looking for a projector, will know a bit more about what the competing technologies have to offer and will find it a little easier to narrow down which is the best projector for your requirements.

If you have any questions or comments, please leave them below.

Thanks for reading!

More by this Author


No comments yet.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.

    Click to Rate This Article