Online Lens calculator - Calculating the theoretical optic limiting resolution

The theoretical maximum optical resolution of optics is determined by diffraction effects of light which mainly depend on the wavelength of the light and the slit (aperture). According to the Rayleigh criterion (remaining contrast of approx. 15 per cent), two image points can still be distinguished when the distance of the points dx = 2 * 1.22 * f-stop * wavelength.

However, this ideal value is hardly achieved because many optical errors, like chromatic & spherical aberration, coma and astigmatism, and mechanical errors (such as centring errors) etc. additionally reduce the lens resolution. The best optic results can be achieved by stopping down the lens by approximately 2 f-stops.

Note: For a simple calculation please select a value from the drop-down box. Even when using the drop-down lists own values can be entered. Please use the first entry "user def."!

Wavelength in nm :	User def. (nm) 360 nm UV 470 nm Blue 530 nm Green 550 nm "White" 650 nm Red 850 nm IR 900 nm IR 950 nm IR
Lens aperture:	User def. (mm) f/1 f/1.4 (1.41) f/2.0 f/2.8 (2.83) f/4 f/5.6 (5.66) f/8.0 f/11 (11.31) f/16 f/22 (22.63)
Theoretical limiting resolution of optical system:

Attention: Wavelengths below 200 nm and beyond 2000 nm are declared invalid. The calculation of extreme values is still carried out and displayed.

Please observe that these values are only references for the achievable accuracy, as they only describe the optics but not the overall system including the image sensor and the entire processing chain plus software evaluation. The required optic resolution particularly depends on the image sensor and size of its pixel structures. Particularly in case of cameras with small pixels, it is important to look for high-quality lenses.

Further details on optical calculations can be found in chapter optic quality.