Does lateral chromatic aberration increase or decrease as you move toward the periphery of a lens?

Does lateral chromatic aberration increase or decrease as you move toward the periphery of a lens?

• A. Increase
• B. Decrease
• C. Remain the same
• D. Fluctuate with wavelength

Answer: (A)

Lateral chromatic aberration grows as you move away from the center because it stems from wavelength-dependent refraction causing different wavelengths to be imaged at slightly different lateral positions. At off-axis field points, rays entering the lens are already refracted to form a larger image angle, and the dispersion (the different bending for blue versus red light) creates a bigger separation between colors as you go toward the edge. In other words, the magnification difference between wavelengths—and thus the color shift—increases with field height, so the color fringing becomes more pronounced toward the periphery. Near the center, this separation is small, while at the edge it’s larger.

Lateral chromatic aberration grows as you move away from the center because it stems from wavelength-dependent refraction causing different wavelengths to be imaged at slightly different lateral positions. At off-axis field points, rays entering the lens are already refracted to form a larger image angle, and the dispersion (the different bending for blue versus red light) creates a bigger separation between colors as you go toward the edge. In other words, the magnification difference between wavelengths—and thus the color shift—increases with field height, so the color fringing becomes more pronounced toward the periphery. Near the center, this separation is small, while at the edge it’s larger.