Optics convert the scene spectral radiance into the spectral irradiance at the sensor in radiometric units. ISET includes several ways to model optics.
Optics can be simulated as diffraction-limited apertures with different f-numbers. They can be simulated as shift-invariant (isoplanatic) systems defined by wavefront aberrations (Zernike polynomials). They can be modeled using ray tracing methods. Other important optics parameters, such as relative illumination (e.g., cos-4th fall off) which results in a darkening of the corners. Microlens effects and anti-aliasing filters can also be modeled.
ISET includes an optics model that reads data (geometric distortion and wavelength-dependent point spread functions) from a lens design specification used by Zemax®.
The GUI allows the user to quickly visualize the consequences of changing optical parameters, such as f-number, focal length and anti-aliasing filters.
Learn more about