Spectral imaging

Radiance

Radiance measures the light energy emitted or reflected by a target, taking into account both intensity and direction across different wavelengths. It is expressed in units of power per unit area per unit solid angle (W/m²/sr). Radiance provides detailed spectral information useful for understanding the material properties and composition of the observed target. It is calculated by adjusting the captured light intensity for factors such as integration time and sensor gain to quantify the energy received by the sensor.

• Integration Time (): The amount of time the sensor is exposed to light, affecting the intensity of the signal.

• Gain (): A factor that amplifies the signal, compensating for low light conditions.

• Raw (): The raw intensity of the captured signal.

• Dark (): The dark reference image, which is used to remove background noise and correct for sensor offsets.

Reflectance

Reflectance represents the relative reflectance of the target and is calculated using the raw intensity of the captured signal, a dark reference image, and a white reference image.

where is the raw intensity of the captured signal, is the dark reference image and is the white reference image.

Absorbance

Absorbance represents the pseudo-absorbance of the image and is calculated based on the reflectance values. This mode is useful for analyzing the material's absorption characteristics.

None

Selecting "None" means using the raw radiance data without applying any dark or white reference adjustments.