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All 3D Glasses Block a Bit of the Light, but How Much Exactly

January 20th, 2010 · 9 Comments · Other S3D Tech

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Everyone is talking about their 3D glasses not blocking as much light as the competitors or not stopping any light at all etc., but does anyone know how much light gets actually blocked when you wear a certain type of 3D glasses? I did a little quick and dirty test to check just that by placing a light meter at a distance of 20 inch (about 51 centimeters) away from display in a completely dark room with no other light sources. Then on the display (120Hz ViewSonic VX2268WM) was shown a completely white image (jps) displayed on the whole screen and I’ve taken out measurements of the light reaching to the sensor of the light meter directly and through a few different types of glasses. The light was measured in Lux units as this way I could measure the intensity of light that reaches your eye without any glasses and when wearing a certain type of 3D glasses based on different technologies…

And here are the results:
– 22″ ViewSonic white, no glasses – 47.2 lux
– 3D Vision active shutter glasses – 41.3 lux (shutters constantly open)
– 3D Vision active shutter glasses – 5.9 lux (per eye with switching shutters)
– Passive circular polarized glasses – 32.1 lux (the glasses from Acer Aspire 3D)
– Anaglyph anachrome red-cyan glasses – 21.9 lux (for red), 22.3 lux (for cyan)
– And a with pair of plain black sunglasses – 15.4 lux

And a little update with more:
– Plain paper anaglyph glasses red-cyan – 7.4 lux (red), 21.3 lux (cyan)
– 3D Vision Discover (anaglyp red-cyan) – 6.3 lux (red), 17.8 lux (cyan)
– Pulfrich paper glasses (clear-black) – 3.5 lux (black lens)

As you can see there is a significant difference in terms of the amount of light that reaches the eye of a person when using different kind of glasses for viewing 3D content with 3D Vision getting the least amount of light passing through. This is normal because of the switch on/off cycle of the shutters in these type of glasses, this however dos not mean that the technology is bad or something like that… it means that just like with other tech you need to compensate with more brightness of the image coming from the screen. But with a passive polarized glasses like the ones from the Acer Aspire 3D you can get more light to the eyes of the user and this is quite important as usually the screens of the laptops are offering less brightness than their desktop counterparts. The comparison with the plain sunglasses is also important, so that you can get a general idea on how things look through the different types of 3D glasses by just taking a look over through your sunglasses and taking into consideration the numbers above. Another thing to note is the difference between the light passing through both color filters on a normal pair or paper anaglyph glasses compared to plastic anachrome glasses (the later have better color reproduction).

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9 responses so far ↓

  • 1 Zerofool // Jan 21, 2010 at 03:03

    Nice idea, hopefully you can compare other shutter glasses in the future (like the XpanD, Bit Cauldron and other ones coming along with the future 3D TVs (some of them will be produced by RealD if I’m not mistaken)). Anyway, if there is difference between shutter glasses it will most likely be caused by different timing settings. As we know 3D Vision glasses remain open ~2ms per frame each, so other devs could up that time to gain higher brighness.

  • 2 Philip Heggie // Jan 21, 2010 at 05:12

    Yes I noticed the brightness was very low from 3dvision glasses and am to keen to know how well Bit Cauldron’s compare and hope they are not much more expensive.

  • 3 Peter // Jan 21, 2010 at 05:14

    And here are the results:
    – 22″ ViewSonic white, no glasses – 47,2 lux
    – 3D Vision active shutter glasses – 41,3 lux (shutters constantly open)
    – 3D Vision active shutter glasses – 5,9 lux (per eye with switching shutters)

    I’m a bit confused about these numbers. The first 3D Vision # is for when the glasses are in a clear state correct? The second 3D Vision # is when the glasses are in a “black” state correct?

    If this is correct then I don’t see a problem here because they let through almost all the light when clear and block almost all of it when a certain eye shouldn’t see the image.

  • 4 ThreeDeePio // Jan 21, 2010 at 07:10

    I am a little confused on the lux units.

    3D Vision active shutter glasses – 5,9 lux – What does the 5 mean vs the 9? Is this supposed to be 5.9? Two separate measurements?

  • 5 Zerofool // Jan 21, 2010 at 07:33

    @3DPO, it’s 5 and 9 tenths = 59/10 :). I suppose that’s the average light intensity that’s detected by the sensor, which is not very accurate for fast changes (like 120 Hz :)) and I really don’t know if this data should be taken seriously, although it’s OK for head-to-head comparison with other shutter solutions (again in shuttering mode) with the same setup.

    @Peter: in “black” state the data ‘should’ be close to 0 (zero), but it will be little higher because of the light bleeding (we are talking liquid crystals here ;))

    @Philip Heggie: Bit Cauldron glasses are actually supposed to be way cheaper than 3D Vision glasses, at least according to current rumors. We’ll wait and see ;).

  • 6 Bloody // Jan 21, 2010 at 10:55

    The measurements fro 3D Vision are in inactive state (shutters open), when they block just a little bit of light and them with shutters active (switching on and off), and not with them being in “black state” (constantly closed). The lower number represents the amount of light that reaches your eye while you are playing in 3D go get an idea how much darker the image looks like on the screen and why you need to compensate with higher brightness from the display.

    People that were able to try Bit Cauldron’s glasses report them to be significantly clearer than 3D Vision for example, but we’ll need to wait a bit more for them to be on the market. As for the price… I don’t think they could be “way cheaper”, but still should be more affordable priced than 3D Vision.

  • 7 Philip Heggie // Jan 21, 2010 at 11:43

    Hope they sell Bit Cauldron internationally on the web :-}

  • 8 Bloody // Jan 21, 2010 at 13:06

    Bit Cauldron won’t be selling the glasses under their brand name and directly to end users, they are only going to produce them. The rest will depend on their partners and I also do hope to have them available worldwide… :)

  • 9 jacob pederson // Jan 23, 2010 at 01:46

    An observation: When I had the Samsung 3d Monitor, I found the 3d vision glasses to be quite dark. I could not read the letters on my keyboard at all with the glasses active. Switching to the Mistubishi, WD-60735, they got quite a bit brighter. I can read my keyboard just fine now. Have no idea why on this. The Mistubishi does require an additional cable between the infrared sync thingy and the television . . . perhaps this has something to do with it?

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