State the Nyquist frequency for a detector with pixel pitch p.

State the Nyquist frequency for a detector with pixel pitch p.

• A. 1/p
• B. 2p
• C. 1/(2p) cycles per unit length
• D. p/2

Answer: (C)

Nyquist frequency in spatial sampling is half of the sampling rate. If you sample every p units, you’re taking 1/p samples per unit length. The Nyquist limit is half of that, giving 1/(2p) cycles per unit length as the highest frequency you can represent without aliasing. For example, with p = 0.5 units, you sample 2 times per unit, so the Nyquist frequency is 1 cycle per unit. Why the other options don’t fit: 1/p is the sampling rate itself, not the Nyquist limit. 2p isn’t a frequency at all in this context. p/2 is not correct because the Nyquist frequency depends on the reciprocal of the pitch, halved, which is 1/(2p).

Nyquist frequency in spatial sampling is half of the sampling rate. If you sample every p units, you’re taking 1/p samples per unit length. The Nyquist limit is half of that, giving 1/(2p) cycles per unit length as the highest frequency you can represent without aliasing. For example, with p = 0.5 units, you sample 2 times per unit, so the Nyquist frequency is 1 cycle per unit.

Why the other options don’t fit: 1/p is the sampling rate itself, not the Nyquist limit. 2p isn’t a frequency at all in this context. p/2 is not correct because the Nyquist frequency depends on the reciprocal of the pitch, halved, which is 1/(2p).