Interference filters 3D
Also called an interference filter technology for commercial theater 3D, manufactured by a German company Infitec. The system uses a projector and does not require a silver-plated screen. Infitec 3D compatible projector with a special color wheel is inserted into between the lamp and the imaging device, the primary color is separated into different segments. Imagine: before the red, green, blue, and now is the Red 1, Red 2, Green 1, Green 2, Blue 1, Blue 2. Special interference filter glasses, allowing the left eye to only see the section labeled fragment of "1" and the right eye only see marked as "2" fragment. 3D glasses use an additional filter to the correct perception of color, the eyes see things as close as possible to the original movie. You may have seen this technology: in the commercial theater, it is called Dolby 3D (Dolby 3D).
Dolby 3D is better polarized 3D system as generally used in cinema projection, but the world premiere of "Avatar" held in London's Leicester Square, the Empire theater, using Dolby 3D.
The advantages of the 3D interference filters
Passive glasses. Passive glasses are the common elements of the 3D system designed for the commercial theater and other large venues, because of its ease of use and relatively low cost. Interference filters compared to the 3D glasses polarized glasses and its manufacture more difficult. Therefore, they are manufactured to have a high durability. The lens is made of glass production, sturdy frame and even a lanyard hole for the anti-theft device. With compared to vulnerable polarized lens, they can better resist scraped and wear.
No silver-plated screen. Decades ago, silver-plated screen is used for all of the movies, but they gradually fell out of favor. More silver-plated screen compared to the white screen viewing angle restrictions, so when the projector is bright enough to fully place lit a white curtain, silver-plated screen to exit the stage of history.
Then silver-plated screen shortcomings still exist: the brightness decreased significantly for viewers sitting off-center. In a commercial theater, which includes a significant part of the audience. Do not need to use polarized view of the interference filter 3D, you do not need a silver-plated screen, thus improving the viewing experience for every audience. The people sitting in the theater on both sides of the screen illumination be able to get more consistent, all the audience can get the color fidelity and non-3D movies.
Interference filter 3D disadvantage
Loss of brightness. Any single projector 3D display compared to the same projector on the 2D display, will suffer a significant loss of brightness. This does not mean that the single projector interference filter 3D and polarized 3D system always has the same brightness, or the implementation of the dual projector always more bright than the single projector system. Single projector polarized system, interference filter system, and shutter glasses system has the common limitations.
Specialized equipment. In a lot of commercial theater has been in use on the DLP Cinema projector install a similar RealD single projector polarized system is feasible, such changes do not need to be modified on the projector itself. Given Infitec 3D mechanism inside the projector, theater, or need to buy pre-installed cinema projector the Infitec color wheel, or a trained engineers need to install the color wheel to their existing DLP Cinema projector internal.
Expensive glasses. The biggest advantage is that they are inexpensive passive glasses, so people may expect Infitec 3D glasses will not be too expensive. Wrong. The Infitec glasses most of the manufacturing cost in that the lens itself - the glass must be carried out multiple coating in order to distinguish between the different wavelengths. Dolby recent about 3D glasses news conference, announced a wholesale price of $ 27.50 per pair of glasses. This is obviously a lot of money in theaters, so many of the procedures used to ensure that the theater audience restitution 3D glasses. I have been to a Dolby 3D theater requirements to provide a photo identification to exchange for glasses.
LCD shutter glasses way
LCD shutter glasses suitable for home use is the first high-quality 3D. In the use of such glasses in the system, the video display to the left and right eye images are alternately displayed, - up to 120 frames per second at a very fast speed. The viewer to wear an active LCD shutter glasses, hinder the left eye and the right eye alternately. Like the effect of the DLP color wheel, like this around the turn so fast that your brain fusion of the two images into one, resulting in a single image 3D sense of depth.
The advantages of the shutter glasses
Color. While shutter 3D glasses, all kinds, but most have without obvious staining the lens, which makes them color accuracy and polarized. We have been in use shutter 3D glasses dyed green, but we've seen other brands of glasses does not stain.
String line. String line LCD glasses may be one of the best all 3D, because the eye is not used by the shutter mechanism active shielding. The early version ghosting problem, that is, before the image of the part will be retained in the new image appears on the screen. The newer, faster display technology has completely eliminated such image error.
Relatively cheap. 3D projector and TV prices have been very low. Today, one is able to display 3D projector only need $ 800 to get. Although there are other costs, for example, is equipped with high-end graphics computers and each viewer pair of 3D glasses, but for only a small audience of family applications, or be able to withstand.
Disadvantages of the shutter glasses
Active glasses. This is the main difference of the LCD shutter glasses and other types of systems: The mechanism of control which eye to see what content is embedded in the glasses internal, rather than determined by the program content or the projector. LCD shutter glasses for fewer trusted adult audience is very good, but it also has several weaknesses. Expensive compared to other technologies, the cost of glasses (in this release, 100-150 U.S. dollars) per pair of glasses. The glasses structure is complicated, with batteries, electrical components, as well as the fragile LCD lens. If you fall on the ground, stepped on, or the battery goes dead, would undermine the viewer's 3D experience. And, if you have a large group of friends to your family want to enjoy the 3D Super Bowl (Note: the United States Football League finals of the year), for each person to provide a pair of 3D glasses too expensive.
Synchronization. Active shutter system needs a way to synchronize the contents of the 3D glasses of the shutter operation and the screen displayed on. Some systems use infrared transmitter. The TI for the projector and the television system known as DLP Link, it uses a sync pulse contained within the projected image. Although the two implementations pulse information using a different signal source, but the pulse is the same.
Left eye pulse and right eye pulse is different, which is why all synchronized to a specific TV 3D glasses, between synchronized. The projector can not know which frame is the eye, leading to an interesting question. These pulses may flip one eye to see the glasses belonging to another screen. In other words, the left eye pulse and associated with the right-eye image in together. This is called "pseudo-three-dimensional effect and this phenomenon will make you feel quite uneasy when the first few to experience. The effect is a strange scene image inside out, as if you are watching from the wrong side of a depression 3D image. This phenomenon is often, so manufacturers have appropriate countermeasures - can be remedied by switching monitors, computer graphics or software itself an option. Nevertheless, it is not as simple and reliable as other types of systems.
Blink. Some people reported that use shutter glasses to see the flashing. Flicker is insufficient refresh rate generated when the effect of an operation stop. Indeed, the view of each eye only accept half the refresh rate of the projector shutter glasses have to be very fast. For this purpose, the current implementation uses at least 120Hz refresh rate of 60 frames per second, the image to be rendered for each eye. In ProjectorCentral test, we have not encountered any flashing, so we can not be the prevalence of this phenomenon or seriousness to comment.
Loss of brightness. Shutter glasses system uses a single projector, fast switching displays different left and right eye images, and other single projector system, compared to 2D have brightness of at least 50% of the reduction in the output. The glasses will also reduce the visual brightness. Although not all of the glasses are the same, but regardless of the display, or the program itself, we tested the model of the visual brightness reduced by about 60%. The advantage is that The glasses also reduces the black level, which significantly increased the contrast.
