Very nice! I really like this.
Some things which came to my mind:
- I would put the required measurement units (metric/imperial) into the name fields of the input values in each calculator (just to make it easier and to avoid user mistakes)
- The spot size values seem high. I’m getting 88m spot diameter @1km with 1.25mm LED “length” and 75m with 1.06mm LED “length”. From my own experience I can say that this isn’t true. My own calulations with 1,06mm LED “length” give me 11m spot diameter.
This can actually be checked easily. Lumens = lux/m^2
So 75m spot diameter at 1km distance would mean that my 1.55MCd light would be putting 6848 lumens into the spot (1.55lux at that distance). I reality it’s around 433 lumens, which your calculator also correctly calculates (if the amount of collected light is indeed true).
I am also not factoring in the corona which is part of the collected lumens. How do you account for that? I wouldn’t consider it to be part of the spot.
Of course I can get the actual values by doing the calulation backwards:
Lets say the spot is 11.27m diameter in 1km distance. So the area is 99.76m^2 and it is lit uniformly with 1.55lux. This means that 155lm are in this spot. Of the 433 “spot lumen” calculated by your calulator (maybe they should be called “reflected lumens” instead?) 433-155=278lm remain for the corona.
- Maybe we can also calculate the size of the corona? My guess is that it is determined by the minimum focal length of the reflector. In my case that is 2cm. So in 1km distance the outer corona would have a diameter of (0.00106m * 1000m) / 2cm = 53m. If it were uniformely lit (it probably is not) we could calculate it’s brightness by using the same circle-with-hole-in-the-middle-principle as we do when determining the area of a reflector (because the intensity that overlaps the actual hotspot is already accounted for in the lumens of it). So in this case 2206.18m^2-99.76m^2 = 2106.42m^2. Now we divide the Lumens by this to get the intensity: 278lm / 2106.42 = 0.132lux.
*If you do all of this maybe you could also implement a drawing which shows the divergence and intensity of the different parts of the beam (calculating the divergence of the spill is probably easy for you).
- If you want to be super precise you can add the area of the LED multiplied with it’s luminance and with the transmission rate of the lens to the calculated luminous intensity (throw).
- Explaining the different parts of the formulas here would be nice I think. For example you calculate the diagonal of the LED die based on the side length to get it’s maximum width.
I am having problems with the metric version of reflector type 1. What do I input for the focal length?
EDIT: I get it now. The focal length needs to be input in cm, not mm like the other values.
I am testing using the values of the Maxabeam reflector:
Diameter: 118mm - 4.65in
Small opening: 40mm - 1.58in
focal length: 10mm
“max focal length”: 94mm - 3.7in
reflectivity: 75%
EDIT2: I am having problems with the imperial version. There seems to be some problem with the geometrical part (the orange reflector curve is not touching the Y-axis where the focal point is when using the test numbers above). The lumen values are also too high.