MicroLED Simulation with Lumerical FDTD

So, in the numerical FDTD, as you see here, we have a substrate. We have different parts, as I showed in my presentation. For instance, here we have aluminum gallium indium phosphide, we have aluminum indium phosphide, so we have a seal, we have multi quantum well.

Here is our multi quantum well again, a seal. How many medium for site, as you see highlighted, all medium can be on this slide. I showed it to you. So, this is the material.

We can manage the material and layer just by right-clicking and selecting "edit object." We can manage the material and layer just by right-clicking and selecting "edit object" and then we can manage the material and layer just by left-clicking and selecting "edit object." Now, you can check; you can read out the reference.

How it will change if the analysis while continually testing it again in the script part. You can see that we have a metal material layer, one layer, two to layer nine. You can add any layer as you wish here. Again, we have a layer thickness.

Like we defined the layer, the material, and thickness in the property section, like here. Then, like this, for loops assign a material and layer for each layer. So, you can see that we can change the number of layers and material and thickness easily by the smart.

After we define the geometry, we can define the simulation region. As you see here in the FDTD, as you see the orange parts, in the simulation region, we have a layer and a layer, and the layer region. Like we select the dimension as 3D. So, our simulation time is like here, 500 femtoseconds.

So, in the geometry, this is the geometry of FDTD we want to cover the whole layers of FDTD in our box. So, here is our mesh setting. We put the mesh accuracy of two. It means that if we put a mesh accuracy of one, it means that we have six points in each wavelength.

So, mesh accuracy of two, it means that we have 10 points in one wavelength. If we increase like mesh accuracy of three, it means that we have 14 points, and so on. Like the trade-off is a time of simulation, but what we can get is a more accurate result.

But here, mesh accuracy of two is enough for us. About the boundary condition, because our structure is symmetric, I use x-mean as anti-symmetric, and y-mean as symmetric. So, the other part, like z, for z, I consider a PML. Also, the early shut-off here, I put one e-minus five.

About this parameter, what we can define is a Historically roasts and coincidentally, it's a Higher walk crashing second type of limiter. So, as an glycogen, we begin to condition it's number and weight charts down to equal to two. We drop a zero and then go up to three.

So, that's going to be the range. We have let's say it simply define a l and a minus 20 right here and raise and 9 1.. and now we put that down. So, as we is 0, it means we demand to create a final deal on the weak VS.

Overall, the times for this wave is xy 10, and we define the geometry, we define the source, and then, like we can define the source. We can define the source. We can add the source from here. So, we put the dipole source. This is our the value of theta is 90. So, the value of theta is .

is 90. So, actually, this is the range of frequency that we want to simulate. And so, also, we put some monitors to see the result. For instance, we put some time monitors to see the light behavior in different times.

We put the different like monitor in x, y, and z direction and also see the far field. So, like in the far field, like we can calculate the power versus theta personal factor transmission and far field.

For instance, for the far field, this is the result of a far field, and you can see for different so uh you can change the way of looking to the far field like xyz plan or or like a radiation plot. So, we will select the xy plan and you can see how it looks like in terms of far field.

So, also, you can change you can see the far fields for different wavelengths present here if I choose as a wavelength as a micro and change the wavelength, you can see how far field changes during the like micro simulation and also the numerical FDTD.

Like we can um you can use uh like uh scripting language. So, I use this uh actually uh this example from the the Ansys website. So, uh, the Ansys website is accessible to anybody, everything with rcfr, and you can find a geodves proposal it's anilah dot org, and you can see that it's remit.

So, these you can always start the environment true if you now go to the closed content program, you can see that the label you can see that feature for example, um, you can see so we can see we now need that for uh a type of code like taj ск EH, I put in the link of this example in my presentation.

Please look at my presentation.

So, um, like the way that will use the script, so we can use the GUI for instance, in the GUI, you can um see okay, like in the z, I want to see the uh the for field, so like you can see this is a far field, like we can use a high l, yeah, and you can see this is a far field for example, it is seem straight out here.

So, this is a far field in a in a z, z monitors, like here, uh, so or like we can uh see the transmission, you see this is a way of transmission, but uh, so one way to look at the result is GUI, another way, we can use a script, like this part, this part, so like here, we read the data from different monitors, like x, z, and y normal, and then we plot the data.

Let's look at just plot this part run selection. So, as you see here, this is the this is a near field in the zip monitors. You can see image x, z, and I calculate the the e square of actually of the y normal, i mean, here.

So, the other way, we can go to the y normal visualize and then we can see the field and then change it to the log scale, and then, like you can see, we can achieve the same result. But the difference here is here we use a GUI, but in this part, we use a script.

So, for instance, for the far field, like far field in the z2 run selection, okay, you can see that this is a far field, like here, we get the data of x, y, and z, z 2. So, next, like here, we use a like again, we calculate the transmission, and here, you can use the data of transmission and plot the transmission.

And this is the way that we calculate the the pointing vector, calculate the p versus theta personal factor, uh, power in angular cone, and if you run all the results, you can see how it works.

So, this is the emitted to air, this is the personal factor, this is a power versus theta, this is a far field, this is a total transmission that we calculate by this. Yes, it's um, numerical FDTD is very useful to calculate and simulate the micro LED display.

If you have any question about how we calculate the the micro LED in your project, close, please reach out to us at support.uzany.com. Thank you.