Light Beam Induced Current (LBIC)

Light Beam Induced Current (LBIC) imaging is a diagnostic technique used to assess the performance and identify defects in solar photovoltaic (PV) modules by measuring the current generated in response to a focused light beam. This method provides detailed spatial resolution of the photovoltaic response across the module, allowing for precise identification of various defects and inefficiencies.

How LBIC Imaging Works

  • Light Beam Scanning:

A focused light beam, typically from a laser or high-intensity light source, is scanned across the surface of the solar module. As the light beam moves, it induces a current in the illuminated area of the module.

  • Current Measurement:

The current generated by the illuminated section is measured using sensitive electronic equipment. The measurements are recorded as the light beam scans the entire module surface.

  • Image Construction:

The recorded current values are mapped to their corresponding positions on the module to create a spatially resolved image. This LBIC image highlights areas with varying current responses, indicating different levels of performance and the presence of defects.

Types of Defects Detected by LBIC Imaging

  1. Operationally Significant Microcracks
  2. Low Shunt cells
  3. Inactive/Isolated Areas
  4. Material Inhomogeneities
  5. Absorption and Reflection Losses
  6. Quantum efficiency of cells at multiple wavelengths
  7. Cell finger electrode discontinuity

Advantages of LBIC Imaging

  • High Spatial Resolution
  • Non-Destructive
  • Quantitative Analysis
  • Full Spectral Coverage

Applications of LBIC Imaging

  • Research and Development
  • Manufacturing Quality Control
  • Testing and Standardization