Question on the Difference between Light Commander and DLP Discovery 4100 Kit

Hi,

The LightCommander supports NIR up to 850nm. It is a great kit for first time users because it has a easy to use software GUI that allows in-depth control of the DMD and the kit can be connected to your PC easily through industry standard IOs. The LightCommander comes with a complete system that is modular and the optics can be changed.

The Discovery 4100 kit is the high performanc, high end kit. It supports a 0.7XGA-IR which goes up to ~2000nm. It can also support very high speed operations (up to 32k frames per second). However, this kit does not come with any optics or light engine. It also only has a limited GUI. This is a high-touch kit which requires some expertise in DLP technology. If you do choose to go with this kit, it is available through one of the DLP partner Design Houses and supported by them. You can find a list of qualified DHs at www.ti.com/dlpdesign.

There are several important differences between these development kits and an off-the-shelf projector. These kits can operate at much high frame rate than a projector. These kits are made specifically for development which include certain hooks that are not available on a projector. In addition, there is a GUI for these that allows you to control the kits in ways that are not accessible on a projector.

So if I choose to go with the Discovery kit, am I correct in assuming that I will be writing code to control it?  And will I be writing the code in some sort of software that comes with the kit (and runs on 32 and 64 bit Windows7)?  If so, I think that will still be fine as long as there is a good reference guide for all the commands as well as some examples of primitive code.  The reason I am asking this is because I need a high resolution DMD chip, and I think that the 0.55 XGA chip that comes with the Light Commander may not have enough pixels.  I am not too concerned about speed or frames-per-second at the threshold that these kits work at, but I do need a high resolution (pretty much why I am focusing on a 0.7 XGA chip that can handle long wavelengths as well) system.  Can I custom order a Light Commander with one of the higher resolution chips or do I have to go with Discovery to use a larger DMD chip?

Also, when you say that these kits include "certain hooks that are not available on a projector" can you elaborate and give examples?

Hi,

The Discovery 4100 has a Xilinx Applications FPGA that you may use to program. It takes either VHDL or Verilog programming language. Unfortunately, it does not have a standard connection to a PC which you can program easily. Some of the Design Houses developed their own APIs that can be used to program. That might be the easiest way to go about it if you choose to use the D4100. Please contact one of the Design Houses for more details.

The 0.7XGA and the 0.5XGA both have the same resolution (1024x768). The number indicates the diagonal length of the DMD in inches. But the 0.7XGA is the only DMD that has the option of an IR window.

Unfortunatley, there is no customization on the LightCommander DMD. It is only available today with the 0.55XGA DMD that supports wavelengths up to 850nm.

These development kits offer features such as the way you load the image. You may choose to "reset", or load the image on a part of the DMD. You can get synchronization signals to sync up to a camera to get the precise timing. You can also choose to use only 1 color (monochrome). These are just a few things that you can manipulate on the development kits that are not available on an off-the-shelf projector.

Thank you very much!

Where can I get a spec sheet for the Light commander that graphs the transmission efficiency with respect to wavelength of the window in front of the 0.55XGA DMD chip?

Shwetadwip,

Many of the team here are on holiday for Christmas/New Years.  Most will  be returning Monday Jan 3rd.  Please allow until then for a reply.  Thank you.

Pascal

Hi Shwetadwip,

Below are the transmission waveforms for the 0.55XGA S450 DMD on the LightCommander.

The top lines are transmission, the bottom lines are reflective. The solid lines are measured and the dotted lines are theoretical.

Hello,

I have a few questions:

What does the "AOI" label mean?

Can I also get a efficiency graph of the reflectivity of the actual DMD micromirror with respect to wavelength?

AOI means Angle of Incidence

The bottom portion of the graph is the reflectivity.

Sorry if this sounds like an ignorant question.

If the bottom portion is the reflectivity of the micromirrors, then this graph says that the actual DMD chip reflects almost nothing (<4%) from wavelengths 400-800 nm.  Are you sure this is the reflectivity of the micromirrors of the actual chip?  I originally thought this was the reflectivity profile of the coated window in front of the actual chip...

Shwetadwip Chowdhury

Shwetadwip,

I'm sorry, I misunderstood your question previously. The bottom curves are the reflectivity of the window. The DMD mirror reflectivity is stated in the datasheet as 88% up to 700nm. I do not currently have the waveform for  beyond that wavelength.

Hello Shwetadwip,

Although not  exact the mirror reflectivity is fairly similar to that of bulk aluminum.  Please see my response in your other thread. 

Light Commander Reflectance and Transmission Spectrum

Fizix

Yes I just saw that thread

Thank you :)