DLP3010EVM-LC: Problem of projecting 2D on DLP3010

Hello Renzhen,

Welcome back to the E2E forum. We are looking into this issue.

My theory is that the data is being split up into the upper and lower bits based on the GUI screenshot that you have attached. How do the camera captures appear with a maximally white image?

Regards,

Austin

Hello Austin,

My understanding is that when splash patterns is operated, the 24-bit deep image is divided into 3 8-bit deep images, and then 2 8-bit deep images are projected respectively, as shown in PData[7:0] and PData[15:8]. There is no high and low situation as you mentioned. When I made a 24-bit deep picture, I divided the data into three 8-bit deep ones, namely PData[7:0], PData[15:8] and PData[23:16]. These three data channels correspond to RGB channels respectively, and I set the value of these three channels to 130. Therefore, when projecting two pictures, the values of the two channels PData[7:0] and PData[15:8] are projected respectively, and the values of the two channels should be 130, and the brightness of the pictures captured by the camera should be the same.

Hello Austin

My camera is a black and white camera, not a color camera, so the picture shown in picture 2 above is black and white, and the actual projection is a blue picture.

Hello Austin

As can be seen from picture 1 above, trigger1 signals will be triggered every time the projector projects 8 bits of data. Columns such as projection PData[7:0] and PData[15:8] will have trigger signals sent from trigger1. The camera will start to expose according to the trigger1 signal, and the exposure time is the same as the projector exposure time 8000us. Therefore, the camera collected the projection signal of PData[7:0] and PData[15:8] respectively, and I set the data value of PData[7:0] and PData[15:8] on the projector to 130. So the brightness of the picture projected by the projector should be the same, but the actual picture is one dark and one light.

Hello Austin,

Here's how I made four splash images. I chose to save in RGB format. My picture format is bmp.

Hello User,

What's the firmware version and GUI version that you used to create the custom image file that include these splash images? There were some known issues with Edit firmware tool in GUI version 3.1.0.7.

The latest firmware version for DLP3010EVM-LC is v9p0p1 and the latest GUI version is 3.2.0.6. 

Regards,

Lori 

Hello Lori,

The firmware version I was using was 8.0.0 and the GUI version was 3.1.0.7. However, today I used the latest firmware version 9.0.1 and the latest GUI version 3.2.0.6 as you said, and the same effect still appeared, but it did not get better.

Do you know what the problem is with this phenomenon? Will you have the same problem as me when using it? How can I solve this problem?

Hello Liu,

Our servers were down for the past two days. We are looking into your questions now and will get back to you next week. Thank you for your patience.

Best,

Maxine

Hello Maxine Cabrasawan,

Thank you, and I look forward to your responses to my questions.

Hello Maxine Cabrasawan,

Do you see why we have the problem that I've described? I am waiting for your answer. thank you.

Hello renzhen,

We are investigating this behavior, please allow us sometime to get back to you.

Regards,

Lori 

Hello Lori Wang,

I look forward to your reply. I want to ask you if what happens when you do the same experiment as me is the same.

Hello Renzhen,

We will be sure to follow up as soon as possible. Thank you for your patience.

Regards,
Austin

Hello Austin Snyder,

Have you found the reason? How to solve this problem. I hope you can help me answer my questions. thank you.

Hello User,

Do you have a photo detector to measure the light output waveform on an oscilloscope corresponding with Trigger Out 1 and Trigger Out 2 signals?

I'm wondering that could be the camera cause this issue. 

I had an experience on the TI EVM and captured the waveforms by using the same settings as you shown in the Splash pattern mode. 

Please share the waveforms if you can measure.

Regards,

Lori 

Hello Lori Wang,

I have a photodetector.

I have two cases here, one is to set the value of the RGB three channels to 255, that is, the value of PData[7:0], PData[15:8] and PData[23:16] are 255. The photo detector and Trigger Out 1 and Trigger Out 2 waveforms appear basically the same on the oscilloscope as yours, and the brightness of the two images projected is basically the same, and there will be no situation where one color is darker and the other color is lighter. There is another situation, if the value of the three RGB channels is not set to 255, the situation as shown in Figure 2 below is that I set the value size of the three RGB channels to 130, it can be seen from picture 2 that the projected two channels measure signals in the photo detector, one is large, the other is basically not. So you have two projected images one darker and one lighter. Since I can't set all three RGB channels of my image to 255 pixels, two images will be projected, one darker and one lighter. How should this problem be solved?
I don't think it's the camera that's causing this problem, as you can see from my two pictures. When the photo detector projects two images, it does receive signals at the same time, but the signals are large and small, indicating that the projected light intensity is larger and smaller. So I think the reason is DLP.
Please tell me how I can solve this problem.
I wonder if it was caused by my splash images with 24 bit depth. I would like to ask how you make 24-bit depth splash images and what format is it.

I would like to add that the measurement sensor I use is a photoelectric sensor, which converts electrical signals of different sizes according to the strength of the light. The stronger the light, the larger the signal amplitude on the oscilloscope. The PD signal on the oscilloscope is measured by the photoelectric sensor.

Hello User,

Thank you for proving the measurement result.

I have one more request, can you please share the Grey130 splash image and the custom .img file that you included this custom splash image?

I think I can reproduce the similar behavior on the TI EVM, but I would like to use the same splash image and the custom .img file as you have.  

Regards,

Lori 

Hello Lori Wang,

I have sent you three images with RGB values of 30,130,255. You see if you can download open. Because I am not a friend, do not know how to send you, can only upload the compressed package in the forum.

I look forward to your reply.

3377.img.rar

Hello User,

Thank you for sharing the splash images. I think I'm ok with these splash images. 

I will need to look into this more and discuss this behavior with our team, please allow us some time and we will get back to you by the end of this week.

Regards,

Lori 

Hello Lori Wang,

Ok, I will wait for the end of your research questions, and I am looking forward to your reply. Have you tried the splash images I gave you? Will there be the same phenomenon as me?

Hello renzhen,

Please see the captures below by using your splash images. top one is grey130, bottom one is grey30. There might be some limitations in Splash pattern mode to display 2 patterns images. Can you say why you chose splash pattern mode? What's your applications? Are you able to use External pattern mode to display 2D patterns?

Regards,

Lori 

Hello Lori Wang,

I project two 2D images for 3D modeling, and I need to project two 2D images. So I chose splash patterns. I do not choose the External Patterns pattern because it is too complicated and requires External transmission of images to DLP, as well as more components and larger circuit boards, which does not meet our design requirements, so I do not choose the External Patterns pattern.

Only 1D patterns can be projected in internal patterns, so it does not meet my requirements, nor can it choose this pattern.

I'm here to talk about my design and see if you have any good ways to help me. What I need to project are 2 2D patterns, and the pixel values in the pattern are arbitrary, and the pixel values between 0 and 255 are possible. I only need blue for the projection. So when I designed the firmware, I saved the patterns I needed into the DLP firmware.

What I want to ask is, is this a pure problem of DLP itself? Is it because of DLP that two images are projected, one darker and the other whiter? Or is the problem caused by the pictures I made, or is it caused by my incorrect operation of some steps? I would like to ask you how to make 24-bit deep pictures for splash patterns. I would like to follow your steps to make a 24-bit deep picture for experiment to see if the same problem can occur.

How can I solve this problem?

Hello renzhen,

Thank you for the information! 

I think your splash images are ok, but there is limitation in splash pattern mode to display 2 patterns in a frame. Unfortunately, we may not have a immediately solution for you, but we will record this and look into further more. 

Regards,

Lori 

Hello Lori Wang,

If you can find a solution in the future, I hope you can reply me on this post.
What I want to know is that you said there is a problem in splash pattern mode. Is this problem caused by hardware or firmware?

Hello Wang,

I would like to ask whether the problem I raised will also appear on DLP2010EVM-LC and DLP4710EVM-LC? Because I don't have DLP2010EVM-LC and DLP4710EVM-LC, I can't do verification. Therefore, I will know whether the same problem will occur in DLP2010EVM-LC and DLP4710EVM-LC next. If this problem does not occur, I will buy DLP2010EVM-LC and DLP4710EVM-LC. If this issue also occurs on DLP2010EVM-LC and DLP4710EVM-LC, I don't need to buy it again.

Hello renzhen,

The splash pattern mode limitation is for all DLP2010EVM-LC, DLP3010EVM-LC and DLP4710-LC. Please notice currently we do not have a plan to improve this feature. 

Thank you for your interest in DLP® technology.

Regards,

Lori