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Hi all,

I have to estimate a photocurrent produced in the following simulation setup.

Photodiode (detector) and LED (spaced 2cm) lie on one axis, oriented toward a wall (radiometer film) which is parallel to the axis and at a distance of about 10cm from the axis. How much photocurrent would an area dA

Further details:

- The photodiode and LED don't point directly to the wall but are tilted to 70 degrees.

- Irradiance on the dAw is in the order of 10

- Geometry is known, that is detector (photodiode) area, dA

It seems to me that I could use

[tex]\phi_1 = L_1\frac{dA_1*cos\theta_1*dA_2*cos\theta_2}{r^{2}}[/tex]

[tex]L_1 = \frac{I_1 }{dA_1*cos\theta_1}[/tex]

Φ

wall elment, θ

If I could supstitute radiance L

wall element dA

so I got stuck here.

There is also another way I can aproach this problem. In simulation, I can turn the photodiode to be a source,

and get irradiance on the same dAw element from the photodiode-source and from the LED. But im not sure if i could use this somehow to estimate the photocurrent.

I have to estimate a photocurrent produced in the following simulation setup.

Photodiode (detector) and LED (spaced 2cm) lie on one axis, oriented toward a wall (radiometer film) which is parallel to the axis and at a distance of about 10cm from the axis. How much photocurrent would an area dA

_{w}of the wall produce on the photodiode if irradiance on dA_{w}received from the LED is known.Further details:

- The photodiode and LED don't point directly to the wall but are tilted to 70 degrees.

- Irradiance on the dAw is in the order of 10

^{-3}W/cm^{2}, I will assume that the wall is totally reflecting and behaves like Lambertian scatterer.- Geometry is known, that is detector (photodiode) area, dA

_{w}area, their distance and normal angles to the connection line are known.It seems to me that I could use

[tex]\phi_1 = L_1\frac{dA_1*cos\theta_1*dA_2*cos\theta_2}{r^{2}}[/tex]

[tex]L_1 = \frac{I_1 }{dA_1*cos\theta_1}[/tex]

Φ

_{1}is the flux (power) recieved by the photodiode of detector area dA_{1}, dA_{2}is the area of thewall elment, θ

_{1}and θ_{2}are angles normals of the dA_{1}and dA_{2}make with connecting line r.If I could supstitute radiance L

_{1}in the equation for the Φ_{1}I could get to the photocurrent, but L_{1}is expressed in terms of intensity I_{1}emitted from thewall element dA

_{1}which is in [W/sr] units and I know iradiance E, which is [W/m^{2}].so I got stuck here.

There is also another way I can aproach this problem. In simulation, I can turn the photodiode to be a source,

and get irradiance on the same dAw element from the photodiode-source and from the LED. But im not sure if i could use this somehow to estimate the photocurrent.

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