[AlexChen93]

Dear Ronald,

The pictures above didn’t seem to post, so I’ll attach an imgur link of the pictures: https://imgur.com/a/NEC8ubq

Regarding the code I’m considering modifying with the polygons:

def MEMSGSLBG(N=1000,per=0.300,duty=0.5,width=0.5,wmin=0.5,wmax=1.5,layer=1,alph=0.39,n=8,wsleeve=5,layerp=2):#memory efficient super gaussian
    
    #name = 'SGSLBG'
    name = 'SGSLBG_N'+str(int(N))+"_P"+str(int(1000*per))+"_D"+str(int(100*duty))+"W"+str(int(width*1000))+"_WX"+str(int(wmax*1000))+"_WM"+str(int(wmin*1000));
    #build from (0,0)
    maxpg =500 #maximum periods per polygon object
    L = N*per;
    tooth = per*duty;
    gap = per*(1-duty);
    bH = wmin/2.;
    with nd.Cell(name=name) as cell:
        for k in range(0,N):
            if k==0: #initialze
                polypts=[]
                polypts_sleeve_L=[]#initialize sleeve polygons
                polypts_sleeve_R=[]
            elif k%maxpg == 0: #close polygon exceeding maximum periods per polygon and start new polygon
                nd.Polygon(points=polypts,layer=layer).put(0,0,0)#place at true coordinates
                nd.Polygon(points=polypts_sleeve_L,layer=layerp).put(0,0,0)
                nd.Polygon(points=polypts_sleeve_R,layer=layerp).put(0,0,0)
                polypts=[]
                polypts_sleeve_L=[]
                polypts_sleeve_R=[]
                
            z = per*(k+duty/2.) #eval at major element midpoint
            fz = math.exp(-.5*pow(((z/L)-.5)/alph,n))
            fzx = (wmax-width)*fz;
            fzm = (width-wmin)*fz;

            rectx = nd.geometries.transform(points=nd.geometries.box(length=tooth,width=width+fzx),move=(k*per,0,0))
            polypts[int(len(polypts)/2):int(len(polypts)/2)] = rectx #insert into polygon list
            rectm = nd.geometries.transform(points=nd.geometries.box(length=gap,width=width-fzm),move=((k+duty)*per,0,0))
            polypts[int(len(polypts)/2):int(len(polypts)/2)] = rectm #insert into polygon list
                    
        nd.Polygon(points=polypts,layer=layer).put(0,0,0)#place at true coordinates any remainder shape

        nd.Pin('a0',width=width).put(0,0,180)
        nd.Pin('b0',width=width).put(L,0,0)

    return cell

I would like to have the grating elements (rectx and rectm) follow a curve, and after talking it over with a colleague, he suggested changing the move part of the code to follow a curve, calculating the points necessary for x, y, and angle. Based off this, we think there will be a problem where the interface where two differently angled elements will have a “dip” in the resulting layout and believe that adding another point on the larger rectangle should do the trick.

Do you think this is similar to the direction you proposed? Is the fix we proposed the correct way to go about it?

Thank you,

Alex

[AlexChen93]

Dear Ronald,

I figured I should be a bit more clear on my structure.

Attached is a picture of a single period element of my Bragg grating. What is labeled as wmin and period will stay constant (for now) and wmax’s height at the midpoint will follow a super Gaussian apodization as it travels along the grating length.

What it would look like for 2 periods. I’ll post what I’m using to make a straight, apodized Bragg grating after this post (I’m not sure how the forum will post it if I switch between the visual and text tab).

 

Thanks,

 

Alex

[AlexChen93]

Dear Ronald,

Unfortunately, I plan to have the grating elements change in size to introduce a super Gaussian apodization to the whole Bragg grating structure so I would need to define multiple polygons for my structure.

Thank you,

Alex

[AlexChen93]

Thanks Ronald! The solution you provided fixed it up.

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