Unable to remove red lines/obtain black background when exporting to bitmap

[jtpausti]

Hello,

I'm trying to use autocad as an intermediate step in a photolithography process. The intent is to export as a dxf from Klayout then convert into a grayscale 8 bit bmp with AutoCad. This allows the photolithography tool to do a gradient write.

However, I have encountered 2 problems:

1. If I'm in 2D wireframe mode, I can get a black background, but there are red polylines on my drawing that mess with how the machine interprets it. I haven't yet found any way to get rid of them.

2. If I'm not in 2D wireframe mode, the red polylines don't show up, but I can't get a black background. Tampering with the display settings only changes the background in 2D Wireframe mode. Editing it in externally in a different program seems to make the file not interpretable anymore.

Fixing either problem would allow this process to work. How can I fix this issue on mac?

Thanks

Examples and dwg:

[maxim_k]

Hi @jtpausti ,

Looks like you use BMPOUT command to export drawing to BMP format.

You can use 2D Wireframe visual Style for exporting your drawing to BMP. In order to get rid of red lines you simply need to change color of the "L1D0" Layer from Red to "0,0,0" (HSL or RGB) True color:

See attached drawing where I changed color of this Layer.

[jtpausti]

This is helpful, thanks! Unfortunately this still results in undesirable seams between the fully saturated and gradient regions. Is there any way to smooth out that polyline between the white and gradient regions? Combining the hatches somehow? Otherwise, I can see if the results come out fine or try editing the image externally.

[maxim_k]

Hi @jtpausti ,

>>>>>to smooth out that polyline between the white and gradient regions

What do you mean?

Do you want to make it thinner?

You can remove this polylines from the drawing, or if you need them, you can use another method to rasterize the drawing:

Print it to PDF with AutoCAD PDF (High Quality Print).pc3 printer, then open resulting PDF in Preview.app and save as raster image (JPG, PNG, TIFF)

[alina.balkanskaia]

Hello, @jtpausti! Nice to see you on Forum! Could you please share with us the details that @maxim_k asked for? This information could be helpful and help experts to find the Solution!

[jtpausti]

The region I'm worried about is the small black line between the white region and the gradient region on both sides, outlined in red here. I'm concerned that the machine will interpret that as the intended exposure at the location, resulting in a strangely formed photoresist structure.

Would I be able to make the polylines invisible or infinitely thin while exporting to bmp? It's the only format this application accepts, and I'm concerned about intermediate exports disrupting the scale of the drawing.

Thanks

Edit: Forgot to include the bmp file

[maxim_k · Accepted solution]

Hi @jtpausti ,

>>>>Would I be able to make the polylines invisible or infinitely thin while exporting to bmp?

Yes, you can move these polylines to another Layer and turn it off before exporting to BMP or other raster format - JPG, PNG.

>>>>It's the only format this application accepts, and I'm concerned about intermediate exports disrupting the scale of the drawing.

You can also use JPGOUT and PNGOUT commands.

If you are worried about drawing scale, you can use the trick with creating PDF at first (as I wrote before, and >>>>here<<<<) and then exporting PDF to raster format in Preview.app