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Setting up and saving spectrum

For reflectance measurements, the light source should be switched on for a
minimum of 15 minutes. The contact probe acts as a light source and also as a
receiver.

Before taking any reading, the instrument needs to be optimized to the current
atmospheric conditions or else the instrument gets saturated.

The calibrated white reference (WR) reflector is fixed to the contact probe and the
reflectance is collected. A straight line at 1 is observed, indicating that all light is
reflected (as it is white), and with respect to this, all other reflectance measurements
are carried out.

The white reference cap is removed, the contact probe is perpendicularly placed on
the coupon surface and spectrum is saved to collect reflectance.

The reflectance values are saved as .asd files and they are converted to .txt files
using ViewSpecPro software.
The detailed procedure for collecting and saving spectrum is provided in APPENDIXB.
1.3.10 Quantum Efficiency Measurement System
Quantum efficiency (QE) is defined as the ratio of the number of electron carriers generated
to the number of photons of a given wavelength that are incident on the solar cell. QEX12M
quantum efficiency measurement system (as shown in Figure 10) is a device that measures
QE of a cell within a module using a non-intrusive approach [9].
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