Light meter for visible and UV light with RS232 output series B103
The sensor measures light
intensity in micro Watt / square cm.
The results of these measurements are sent to a PC.
The letters shown on the screen are the following for the
The results of these measurements are sent to a PC. The letters shown on the screen are the following for the measured values:
UVL = UV light intensity RED = Red light GRE = Green light BLU = Blue light
Like any analytical instrument there are many other things you can
do with it. The output from your measurement
shows in the PC and instead of using the calculated data’s from the
sensor you can create your own calibration by using the formula above or
Instant analysis calibrates the light intensity in the
microprocessor from the sensor. To recalibrate simply use your own
calibration method = light intensity and correct the incoming data’s
from the sensor. You always can use the values from the sensor as default.
You can calculate the new values or
put the formula in your PC software. Calibrated
to 10 micro watt / square cm for max output.
Figure 1: Spectral Intensity of UV and visible light calibrated to 10 micro watt / square cm for max output.
Figure 2: Same as figure 1 with the addition of a typical light bulb and its output.
Example to show total light energy (figure 1):
A halogen light with 3000 Lx is shown into the sensors aperture and the following calculations are done:
a) total energy: convert 3000 Lx to Watts - 0.0015 × 3000 W = 5 Watts
b) This energy has to be seen in a sphere of 1 meter radius, the surface area is 12.5 cm2
c) The sensors aperture is 10 mm2
d) The light energy going in to the sensor in one meter is: (5 watts × 10 mm2) ÷ (10 cm2) = 5 micro Watts
Example to show light measured with a sensor (figure 2):
The total amount of the energy of the light bulb includes a part of the infrared light. Light energy seen over the spectra is measured in the light sensor. Light energy for each color is the following:
The integral from the sensitivity of the sensor in its spectra x part of the light energy from the spectra going in the sensor. In this example the sensor shows the following outputs:
UV - 1.33 micro Watt / cm2
Blue - 1.63 micro Watt / cm2
Green - 2.38 micro Watt / cm2
Red - 3.12 micro Watt / cm2