About the blog and planned series on laser projection

Before I get back to finishing the story about how pico projectors can be “useful,” I wanted to say a few  things about the KGonTech blog and address some comments that have been made both public and private.

I’m happy to discuss and defend my statements but don’t ask me to reveal confidential information.   Also if you disagree with something that I’ve written, please be specific about where you think I am wrong.  I do occasionally make mistakes.

Direct Green Laser demo put together by Syndiant at CES 2011

If you don’t believe that I have a good idea of what is going on with lasers in spite putting together  Syndiant’s CES 2011 demonstration of the first side by side projection with direct blue and green lasers from Soraa, OSRAM, and Nichia (see picture above), then there is nothing I can do to help you.    I also can’t help that some companies, in my opinion, are giving the perception that the direct diode green lasers are much farther along that what the laser companies have personally told me.

As big a proponent of laser projection as I am, I don’t think it does the pico projector industry any good to set unrealistic expectations for the volume production of green lasers.   It’s simply not realistic to think that a product that can’t be built today with the efficiency and brightness required at any cost, is suddenly going to be mass produced in less than 1 year.   The burden of proof should be on anyone that says that it can be done.

Since there seems to be a lot of interest in laser projection today both in general (and I was the lead author of a distinguished paper at SID this year on the subject  click here for the paper itself) and in the comments on this blog, I am starting to work on a series of blogs to explain the basic issues and numbers with laser projectors.  It is not going to be a technical deep dive, but rather a discussion of the common issues and what can be expected in terms of light efficiency.  Its going to take a series of blogs that I plan to combine into one article as the blogs are posted.  I’m not going to divulge any secrets, but I hope to put some good layman level information in one place so people can intelligently draw their own conclusions.

I plan on starting the laser information series next week and maybe I will do one or two a week for a while until I feel I have fully covered the subject.

One last thing don’t have a “short interest” in any stock and anyone that says or implies that is promoting a falsehood.   I’m fond of saying that you never know when a dumb rich person will buy a company (I’ve seen it happen a few times).

14 comments

  1. me_wwwing says:

    With the laser light having to be spread out to cover the display panel. i can see why you are saying lasers and LCoS display panel don’t play well together.

    your misleading the reader. you should mention that spreading out the lasers light DOES not work well WITH LCoS DISPLAYS. AND this is WHY DLs need to be higher lumen.

    then the reason WHY you wrote:

    ‘I don’t think it does the pico projector industry any good to set unrealistic expectations for the volume production of green lasers.’

    makes sense.

    • KarlG says:

      First, I never wrote that Laser and LCOS “don’t play well together” (please cite where you saw that). To the contrary, I expect that Laser and LCOS are going to be the best combination I know of for making a small/embeddable, low cost, and power efficient projector. I think you should read the SID paper I wrote more carefully.

      Spreading the light to fill the panel has very little light loss so what you are saying is technically silly. What does spreading the light have to do with a major light loss?

      There is some light loss in “overfilling” the panel (some of the spread light going past the edge of the display) but this will be reduced over time with things light holographic optics that can more precisely spread the laser light.

      Having the laser light spread has advantages in being able to despeckle the laser light and in eye safety. But spreading the light itself only has a relatively small light loss.

      • Martin Hillerby says:

        Do you know how Soraa has reduced the speckle in their DGLs ?

        • KarlG says:

          Of course, I have been using their lasers in demos. One of the big advantages of direct diode lasers is that they have a broader bandwidth of light output than frequency doubled/synthetic lasers. The doubled laser typically have a 0.1nm spectrum whereas most of the diodes have a 2nm bandwidth. While the direct diode lasers look much better even with out other despeckling, there still needs to be some despeckling if you want an image that looks about as smooth as that from LEDs. Speckle perception is not a linear function in that you might think you could reduce it by 20 to 1 and that would be good enough, but you eye will still pick up the speckle so you need much more reduction than you think.

          Something the beam scanning companies don’t talk about is “single-mode” versus “multi-mode” direct diode lasers. Mult-mode laser “hop” which further reduces speckle in the case of panel projectors because it averages out but in the case of beam scanning, the hopping ends up looking like noise because the hoping every so many pixels in the scan process. In fact, you can make a single mode laser hop by putting some medium frequency noise into the laser drive. Single mode lasers are harder to build and are less efficient. As the laser companies go to high light output the lasers naturally want to hop/become multi-mode.

  2. me_wwwing says:

    sorry on the -i can see why you are saying- i should not put words into your statement.

    i should have said today’s Lasers and LCOS “don’t play well together” because we don’t see many pico size laser + LCoS projectors. the lasers are out there to make it happen.

    spreading the light out. as your comment says. -But spreading the light itself only has a relatively small light loss.-
    it is a loss and a loss on the over all efficiency of the panel systems.

    adding a vibrating despeckle unit seems to add to the size of the projector and efficiency.

    then there is the projection lens adds to the size of the projector.

    3M has stayed away from going with lasers. maybe these are some of the reasons they have not jumped on the laser band wagon.

    do you think a LCoS Laser system can be made small enough to capture a market share in the cell phone market?
    bTendo, Lemoptix and Microvision have smaller projectors.

    again – i’m sorry for putting works into your statement.

  3. KarlG says:

    You don’t see many LCOS+Laser projectors in the market due to the cost of lasers and the fact that LCOS devices will work with relatively inexpensive LEDs. LCOS will be much more efficient, smaller, and eventually less expensive with lasers than LEDs, but only after the lasers are perfected (which they are not yet).

    The are other ways to despeckle other than electro-mechanical vibration.

    3M is building products and expects to make a profit. Lasers are just not cost competitive today. Most companies will stay with LEDs until the cost comes down and the efficiency is better with lasers.

    Your making apples to oranges comparisons comparing lab prototypes to products that are actually selling. LCOS with lasers can be very small as well, but today they are bigger to be more efficient with LED illumination. I don’t think bTendo and Lemoptix have any product in the market. Microvision had to build the whole projector (my guess is that any “real” business told them that it was too expensive) and then had to heavily subsidize (lose money) each projector just to sell it. When these companies can make a product and convince a company you have heard of before to build a product around it, come back and we can discuss it.

  4. me_wwwing says:

    aren’t you comparing Syndiant LAB prototypes too?

    do you think a LCoS Laser system can be made small enough to capture a market share in the cell phone market?

  5. KarlG says:

    I fully expect that laser illuminated LCOS will dominate embedded pico projectors. They will likely be about the same size but with better resolution, no visible speckle, an more power efficient than laser scanning projectors. Oh, and buy the way, they will be Class 1 (totally eye safe) something that laser scanning projectors can’t be above about about 1 lumen.

  6. me_wwwing says:

    i’m not really bother by the laser safety in scanning projectors.
    right now Microvision is getting approval from the FDA.

    >LCOS will dominate embedded pico projectors.<
    they could if they get small as the companies i mentioned. don't see that happening.
    1. thickness of an encased LCoS panel will be a disadvantage.
    2. Lens size will keep the thickness at a disadvantage.
    i've seen some articles to make the lens thinner on the length. but not on it's height.
    3. how the despeckling will be handled.
    the electro-mechanical vibration seem to have an advantage because it also acts as a mirror to reflect the light. this helps keep the shape of the projector in a box shape. if not the shape ends up being odd shaped. not good for packaging.
    4. the x-cube used to get the light to cover the LCoS seems to be married to the size of the LCoS. not sure it can be made smaller. doesn't the incoming light need to cover the same size of the LCoS diagonal.

    i would like to hear more about the power comparisons.
    like breaking them down:
    – lasers working with 1 or 2 MEMS turn on a off 'vs' LCoS.
    – laser driver power.
    – Video ASIC
    – MEMS ASIC vs LCoS
    – power to run a electro-mechanical vibration for despeckling

  7. bobby says:

    discovered this patent application by panasonic(mvis partner). they seem to want to use lcos with laser beam similar to the argument(stance) you have taken and spoken of many times. my question is “what do you make of panasonic(mvis partner)filing a patent to do this and what could it possibly mean for mvis?”.

    live long and prosper
    how i’m comin’?

    • admin says:

      First, I think you are confusing “Panasonic” and “Pioneer.” It is Pioneer that is working with Microvision on an automotive after-market HUD display. Panasonic has developed a 50 lumen laser projector (using their own frequency double green lasers). Panasonic’s laser projector is “Class 1” lasers at 50 lumens were Microvision with LBS is “Class 2” at only 15 lumens (see for example: http://www.picoprojector-info.com/panasonic-demonstrates-laser-optical-engine-lcos-pico-projectors).

      I really don’t think laser beam steering (from Microvision or anyone else) is going to be much of a factor in the market. There are so many issues beyond just the cost and availability of green lasers that will work with laser beam scanning that LBS is a non-factor today and for many years to come. It doesn’t matter who they are/are not working with, there are just too many major technical issues.

  8. Ed E says:

    Been following your commentary on green lasers and given what has been published, or lack thereof on progress, your statements on GL volume seem more a reality as we continue to into 2012 with nothing really published on it. Do you have any insight on the recent sumotomo-sony breakthrough announcement and how it may or may not revise your estimates on GL production and costs?

    • admin says:

      Thanks,

      I have had a tremendous amount of contract work that has come in and I have fallen behind on commenting on current events.

      Regarding Sony and Sumitomo recent announcement. Sony was much quieter than Soraa, OSRAM and Nichia but it certainly should be expected since they developed blue lasers for blue ray (see for example from 2007 “Sony’s Blue Laser Diodes Down to $8 – PS3 and BD Player Price Cuts Soon?”. Another company to watch would be Opnext who is a leader in red lasers and announced a blue laser diode back in January 2011. All the green laser diode developments I know of came from “stretching” their blue laser development to get green.

      Ok, with that as a preamble, to your question as to the impact of the Sony-Sumitomo announcement’s impact. I can’t see it changing anything in the short run. It looks on the spec’s to be better than other companies’ prior announcements with a 100mW, 530nm wavelength (which is about the best), and 8% WPE which when you factor in the luminous efficiency of the 530nm is about double any other announcement I have seen. Sony has a major investment in LCOS so I would suspect (I have no inside knowledge) that Sony would be looking to couple this laser with their LCOS developments.

      100mW probably only supports about a 20 lumen projector which is pretty dim except for a very dark room or a very small image. Now the bad news, a projector using an 8% WPE green laser probably probably does not have net a efficiency advantage over a good LED projector with at 20 lumens. And then we have to ask how far away is the Sony-Sumitomo green laser diode is from being a product and how much will it cost. Today a green LED to support a 20 lumen projector probably costs about $2. The big question is whether a ~20 lumen project has a value proposition today with what a laser projector will cost to make.

      Anyway, that is the way I see it,
      Karl

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