# Does the size of CCD/CMOS of a telescope affects the magnification?

For a normal, traditional telescope, the magnification level should equal to focal length divided by eyepiece diameter, i.e., $$Res=\frac{f}{D}$$ So does the size of the CCD/CMOS the same as eyepiece diameter in this case? Or the magnification level is not affected by the size of the CCD/CMOS?

The magnification of a telescope is the ratio of the focal length of telescope over the focal length of the eyepiece. At least for a telescope that you want to look through with your eye. The equation you show in your question is the f-number $$N=f/D$$ with focal length $$f$$ and pupil diameter $$D$$. There are a bit convoluted conventions for its usage, but in the end it characterizes the light collection of the telescope.
Besides aperture, magnification and field of view, a telescope is also characterized by its resolution. For an ideal telescope (diffraction limited), the resolution is limited by the wavelength of the light and its pupil diameter $$D$$ (Rayleigh criterion). The resolution of the CCD chip, i.e. its pixel size, has to be designed correctly to sample the telescopes resolution correctly.