MEEP Project #4 sensor

[qnach]

Has anyone done MEEP project
Meep Project #4 — Near-Infrared Absorption Spectra of CMOS Image Sensors
http://www.simpetus.com/projects.html#meep_grating

Other than a few typos in the .sh files it is strange onthe first time I run it
I got several error message in the .py code saying dividing by zero.
There is a division by t which will be zero at t=0

What is strange is when I run the program for the second time....such error message do not pop up....

I did not delete the files generated in the first run. Is that caused such difference?

[oskooi]

That tutorial may be a little out of date. A similar calculation is demonstrated in Tutorial/Diffraction Spectrum of a Binary Grating.

[qnach]

1. The link you provide is for Scheme Interface whereas I am using Python.

2. which point is out of date? I find this example fit my need well....binary grating seems to be another story....

I am trying to calculate solar cell/sensor performance.

[qnach]

i am looking for collaborator to work on sensor/solar cells. i do not have fast enough computers except a small notebook acer swift1 amd cpu 1.1g. for several months after i installed meep i have not been able to finish project 5 (or 4 now). if anyone has computing facility a small modification of the example can results in one or two papers. Ardavan Oskooi ***@***.***> 於 2025年12月11日 週四 14:48 寫道：

…

That tutorial may be a little out of date. A similar calculation is demonstrated in Tutorial/Diffraction Spectrum of a Binary Grating <https://meep.readthedocs.io/en/latest/Python_Tutorials/Mode_Decomposition/#diffraction-spectrum-of-a-binary-grating> . — Reply to this email directly, view it on GitHub <#3125 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADU7Z55WGVRDJKHZRQTMV7L4BEHSPAVCNFSM6AAAAACOV4ORW6VHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTKMRSG42DMMY> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[qnach]

Has anyone done MEEP project Meep Project #4 — Near-Infrared Absorption Spectra of CMOS Image Sensors http://www.simpetus.com/projects.html#meep_grating

Other than a few typos in the .sh files it is strange onthe first time I run it I got several error message in the .py code saying dividing by zero. There is a division by t which will be zero at t=0

What is strange is when I run the program for the second time....such error message do not pop up....

I did not delete the files generated in the first run. Is that caused such difference?

Here is the error message again.

[qnach]

Firstly, the run_cmos.sh has several file names typo and the grep command is grep incorrect text flux1 instead of flux2.
Here is the correct run_cmos.sh:

#!/bin/bash

for a in seq 0.40 0.02 0.70; do
## Python
mpirun -np 4 python cmos_sensor.py -a ${a} > cmos_a${a}_empty_flux.out;
## Scheme
# mpirun -np 4 meep a=${a} substrate?=false cmos-sensor.ctl > cmos_a${a}_empty_flux.out;
grep flux2: cmos_a${a}_empty_flux.out |cut -d , -f2- > cmos_a${a}_empty_flux.dat;

## Python
mpirun -np 4 python cmos_sensor.py -a ${a} -substrate > cmos_a${a}_flat_flux.out;
## Scheme
# mpirun -np 4 meep a=${a} substrate?=true texture?=false cmos-sensor.ctl > cmos_a${a}_flat_flux.out;
grep flux2: cmos_a${a}_flat_flux.out |cut -d , -f2- > cmos_a${a}_flat_flux.dat;

## Python
mpirun -np 4 python cmos_sensor.py -a ${a} -substrate -texture > cmos_a${a}_texture_flux.out;
## Scheme
# mpirun -np 4 meep a=${a} substrate?=true texture?=true cmos-sensor.ctl > cmos_a${a}_texture_flux.out;
grep flux2: cmos_a${a}_texture_flux.out |cut -d , -f2- > cmos_a${a}_texture_flux.dat;

done;