LightCommander synchronization

Hello Fil mag,

I will answer your clarification except the LABVIEW related stuff. Lets wait to see if any of the user(s) is/are able to control the kit from LABVIEW by importing the LightCommander API functions.

Can you explain what kind of measurements are you intending perform?

The 'Video Mode' configuration is not recommended if you are trying to get the LightOutput as linear function of input pixel weightage i.e., ON/OFF in case of 1bpp bit depth or 8bit 256 greyscale level incase of 8bpp bit depth configuration. When configured in Video Mode, the input data to the LightCommander goes through degamma correction and dithering to produce more grey scale levels to make video look better. So, Video mode is good for viewing only not for any measurements.

I recommend you to configure LightCommander(TM) in Structured Light Mode with data source as "DVI" i.e., the PC input in your case. Also make sure on the PC side the data sent is as it is,  that is data o/p must NOT be gamma corrected in other words pixel values sent as it is without any adjustment like gamma, gain, etc..

Regards,

Sanjeev

Hello Sanjeev,

thank you for your input.

The measurement I'm taking is performed with a A/D converter connected to a photodiode amplifier circuit.

Let's then wait to see if someone has any input related with LabVIEW usage of the LightCommander API.

Best regards!

Hi Sanjeev,

I still have one question, in structured light mode, using DVI port as input, do the DMD mirrors change their status if the image to be displayed is always the same, i.e, are they time modulated? Even if the image is binary (black and white)?

I'm asking this because the DLP LightCommander control software specifies frame rate (Hz) and patterns/frame when setting the structured light configuration.

By the way, I've not been able yet to use the DLP Lightcommander API with LabVIEW, so if someone has been able to do it previously, I'd kindly ask that person to provide some input...

Thank you very much in advance!

All the best!

Hi Fil mag,

Structured Light mode using DVI port basically provides a memory space of 24binary patterns. Each bitplane is displayed for fixed duration of time in structured light mode. So user can select the frame-rate 6-60Hz and number of patterns per frame 1 to 24 for binary pattern mode and 1 to 3 for 8bit pattern mode. The mirrors change status as they start showing each bitplane. So whethere the mirror change status depends on incoming data.

In your case the incoming video is black&white in the RGB888 data format but inside the LightCommander(TM) because of SL mode configuration it use video frame data as 24 binary bitplanes; the data will be displayed as follows.

bitpalne#0-bitplane#7               - R8

bitplane#8-bitplane#15            -  G8 

bitplane#16-bitplane#t23         - B8

For example - If the input frame RGB888 is ALL BLACK(0x00 0x00 0x00) or ALL WHITE (0xFF 0xFF 0xFF) which means each bitplane has same value '0' or '1'. So mirror remain in same state for entire repriod so you will see light output constant for entire frame.In anothe extreme case say input frame RGB888 is (0xAA 0xAA 0xAA or 0x55 0x55 0x55) then mirror change state between every bitplane.

Regards,

Sanjeev

Hi,

I also would like to know if it's possible to drive the LightCommander using Labview.

Are labview drivers made available as part of the dev kit?

Thanks,

Dan

Daniele,

Our X3 implementation of the LIghtCommander electronics provides a DLL file from which you can make calls to from Matlab or Labview. This talks our our FPGA, which has its own pattern generation function and timing control. Contact us if you want further info.

Regards,

Adam

Keynote Photonics