Introduction to 3D technology

It seems like everyone is talking about 3D this year, even though half of them think 3D is dead before it even started, and the other half know full well that 3D is simply the next step in the evolution of video display. digital. In fact, much of the technology touted as amazing new 3D has been around for 20 years or more. Let’s take a look at the top 3 types of 3D displays out there so you know what the local electronics store is trying to sell you the next time you go to upgrade your TV.

First though, what the heck is 3D and why is it so important?

3D is the way the average human sees the world around them, although you should know that not being able to perceive in 3D is actually a fairly common disability among many adults. However, assuming you see the world around you in 3D, how can you artificially produce and reproduce something in 3D, like a movie or a video game?

Being able to see in 3D means that your vision has a sense of depth, of how far objects are from your eyes. Your brain automatically calculates this by combining the images it gets from your left and right eyes, and calculating the small differences that occur when you look at something from a different angle. You can see what I mean by holding a finger in front of your eyes and looking straight ahead. Close one eye, then open it and close the other. Do this quickly and you will see how different each one looks. Your finger is in a completely different place for each eye, but your brain rematches them and realizes that means your finger is close to you.

Making a 3D movie is as simple as using two video cameras, which are set together at roughly the same distance as the human eye. Each one takes a slightly different recording, which when played back in the human brain can show you not only the visual scene but also the depth of everything you see. If the movie was animated on a computer, converting it to 3D is easy, as it just involves re-rendering all the movie data from a slightly different angle. If the movie is shot with 3D in mind from the start, as Avatar was, the effects are amazing.

3D gaming is actually incredibly easy to make, as all the data needed to figure out where each object is in 3D space is stored directly on the computer and can be processed in real time. In fact, many of us were playing 3D PC games 10 years ago, and the technology is exactly the same as many 3D TVs and theaters today.

Assuming you have some 3D data, whether it’s a movie, a computer-generated animation, or a video game, the problem is how to display it to the viewer. This is the technological aspect that we are going to discuss a little bit today.

Before I explain some of them though, let me just say that I won’t talk about those tacky red/blue glasses you get with old cheap 3D DVDs and comics, as that’s not real 3D and the quality is shockingly poor, apart. due to the fact that everything you see is colored red and blue!

All of these 3D technologies essentially come down to how do you get that slightly different image to each eye separately, without the other eye seeing it as well. Since normal TVs show the same image to both eyes no matter what you do, 3D is impossible on them. That’s why it’s absolutely necessary to buy a new TV if you’re going to watch any kind of 3D material.

But how can we deliver a single image to each eye?

1. Passive Polarized Glasses:

Polarization means making light rays point in only one direction. Normally, the like comes at us pointing in all different directions. A polarizing filter only lets in light from one direction. They are generally used in photography to prevent reflections; For example, if you were to try to take a picture of a window, you wouldn’t really be able to see the other side, as the light would bounce off your lens. With a polarizing filter, you would remove that and be able to see whatever is on the other side of the window.

The unique and useful properties of a polarizing filter mean that by combining 2 filters, we can make a sort of dimmer for light. If you take two pieces of polarizing film (think high school science class now) and rotate them slowly, at one point they will let most of the light through and at another point they will let most of the light through. This is because, in the first instance, the direction of the light is aligned by the first filter that the next filter allows it to pass through. However, when you rotate the second filter, you are doing it slowly so that the aligned light cannot pass through and reach your eye.

However, in terms of 3D technology, being able to filter particular light beams so that each eye can see them or not means that we can deliver a unique image to each eye at the same time. As? We have two images on the television side of things, and each can be polarized in a different direction. We then add the same filter to a pair of lightweight glasses, and each eye will only see light that is polarized in a particular direction.

This is basically the cheapest method of making 3D, and it’s far from perfect. It is used in large 3D theaters where the quality of the movie is not as important as the experience, and probably not a full-length movie, like at Disney World for example. The main benefits are that the glasses are lightweight and incredibly cheap to produce, so it doesn’t really matter if people break them or misplace them.

There are several cheaper 3D TVs being produced for the budget market this year, but I suggest you stay away from them. You tend to get a lot of blurriness between images (so you can see both left and right at once), and you really need to be in a dark room to get the best of this kind of 3D. Dolby also has a proprietary system that apparently produces better quality than standard filters and is currently used in several better 3D theaters.

2. Active LCD Shutter Glasses:

This is the best quality 3D you can get right now, and anyone who harped on how good Avatar was probably went to see it using this technology. The active LCD shutter means the viewer has to wear some pretty bulky glasses: each eye has a separate LCD screen inside it, as well as an infrared signal receiver that connects it to the movie being played. Unlike passive polarization which only displays both images on the screen at once, active shutter methods display one frame after the other, alternating between views intended for the left and right eyes. The glasses’ LCD screens turn on and off in sync, blocking one eye and then the other. This goes on and off so fast that your brain just combines the two images and forgets about the other 50% part where each eye couldn’t see anything.

The advantage of this method is that the quality is excellent, with almost no “bleed” from one image to the other. Unfortunately, some people claim that it gives them a headache. In all my years of playing games with NVidia’s LCD active shutter glasses, I’ve never had a headache, so I suspect the problem is perhaps something you get used to. When television first appeared, I suspect there were similar complaints from a large section of the population.

This will be the 3D platform of choice for consumers for many years. Yes, the glasses are annoying, but then again, we won’t be seeing everything in 3D. When I sit in front of my PC to play a 3D game, for example, I barely notice them. The latest incarnation of NVidia’s LCD shutter glasses is fairly lightweight, wireless, and recharges from a small USB socket. The bulky models you get in high-end 3D theaters are no longer bulky because of old technology, but simply to make them more resistant to wear and tear and discourage you from taking them home. However, if you’re really against wearing glasses to view 3D content, well, you’re going to have to wait a long time. Which brings us to the third method.

3. Parallax Screens:

Parallax 3D displays display 3D content without the use of glasses. Although there are many competing technologies and they are rapidly evolving as we speak, the basic principle is that both images are displayed on the screen, then some sort of filter bounces the images in different directions. When viewed from a certain angle, the 3D effect is seen. Most offer a choice of about 6 different angles you can view from, but outside of those you’ll lose the 3D effect and just see a two-image blur.

It’s a relatively new technology and was first shown off last year in the form of the words Fujifilm’s first consumer 3D camera, which I had a chance to play around with. The camera took 3D images and was able to simultaneously preview and play back those images on its small, glasses-free 3D screen on the back. This year, the Nintendo 3DS will use a similar but somewhat refined version of the same technology to bring portable 3D gaming to the masses.

My experience with Parallax displays has been less than impressive. First of all, keeping your head in a fixed position is just annoying. Especially if you are viewing something in 3D, your head has a natural tendency to move and wants to view it from different angles. Also, the depth that you can perceive on one of these screens is quite poor. It doesn’t really “pop” on you at all, even if it does look like it’s 3D. I’ve yet to see the 3DS though, so I won’t comment on that until it’s available. Either way, this kind of 3D isn’t coming to big 3D TVs anytime soon, if ever.

I hope that gives you a little insight into all this new technology. Don’t forget to check out my other tech tutorials.