Supplementary Optical Parameters for Solar Simulator Evaluation<\/p>\n\n\n\n
Optical angular characteristics are supplementary optical parameters used to describe the direction and spread of light from a solar simulator.<\/p>\n\n\n\n
These parameters are not a replacement for the main solar simulator performance items such as spectral match, spatial non-uniformity, temporal instability, and irradiance.<\/p>\n\n\n\n
They are used when the incident direction, beam spread, or angular behavior of light is important for a specific application.<\/p>\n\n\n\n
SAN-EI previously used CHA (Collimation Half Angle) as a practical indicator of the directional characteristics of light.<\/p>\n\n\n\n
CHA was useful in practical evaluation, but it included several different aspects of light behavior in a single value, such as the direction of light, the spread of light, and variation across the irradiation area.<\/p>\n\n\n\n
SAN-EI now separates these elements into clearer optical parameters to improve understanding, reproducibility, and technical communication.<\/p>\n\n\n\n
Parameter Meaning Purpose<\/p>\n\n\n\n
Chief Ray Angle (CRA) Deviation of the main light direction from the reference axis To evaluate the main incident direction of light<\/p>\n\n\n\n
Beam Divergence Spread of the light beam during propagation To evaluate how much the light spreads<\/p>\n\n\n\n
Angular Uniformity Variation of incident light direction across the irradiation area To evaluate angular variation within the effective area<\/p>\n\n\n\n
Angular Stability Temporal variation of the light direction To evaluate whether the light direction changes over time<\/p>\n\n\n\n
This update changes the method of expression and evaluation only.<\/p>\n\n\n\n
It does not change the actual optical performance of SAN-EI products.<\/p>\n\n\n\n
Previously provided CHA data remain valid as reference information.<\/p>\n\n\n\n
Optical angular characteristics are useful for applications where the incident angle, beam direction, or beam spread may affect the result.<\/p>\n\n\n\n
Examples include optical material testing, exposure applications, optical alignment evaluation, and other non-standard solar simulator applications.<\/p>\n\n\n\n
For standard photovoltaic solar simulator evaluation, the primary performance items remain spectral match, spatial non-uniformity, temporal instability, and irradiance.<\/p>\n\n\n\n