Which term describes the highest spatial frequency that can be recorded by a digital detector?

Which term describes the highest spatial frequency that can be recorded by a digital detector?

• A. Spatial Resolution
• B. Contrast Resolution
• C. Modulation Transfer Function
• D. Nyquist Frequency

Answer: (D)

The key idea is the sampling limit set by the detector’s pixel size. In digital imaging, what you can represent without distortion is governed by how finely you sample the image. The Nyquist frequency is exactly half of the sampling rate, so it defines the highest spatial frequency that can be recorded without aliasing. In practical terms, if your detector has pixel pitch p, the Nyquist frequency is 1/(2p) cycles per unit length (for example, cycles per millimeter). Frequencies higher than this fold back and create artifacts, so this limit tells you the maximum detail you can rely on from the image. Other terms describe related aspects but don’t specify this hard cutoff: spatial resolution describes the ability to distinguish details, contrast resolution refers to gray-scale discrimination, and the modulation transfer function describes how accurately those frequencies are transmitted across the system rather than the cutoff itself.

The key idea is the sampling limit set by the detector’s pixel size. In digital imaging, what you can represent without distortion is governed by how finely you sample the image. The Nyquist frequency is exactly half of the sampling rate, so it defines the highest spatial frequency that can be recorded without aliasing. In practical terms, if your detector has pixel pitch p, the Nyquist frequency is 1/(2p) cycles per unit length (for example, cycles per millimeter). Frequencies higher than this fold back and create artifacts, so this limit tells you the maximum detail you can rely on from the image. Other terms describe related aspects but don’t specify this hard cutoff: spatial resolution describes the ability to distinguish details, contrast resolution refers to gray-scale discrimination, and the modulation transfer function describes how accurately those frequencies are transmitted across the system rather than the cutoff itself.