detector.py 文件源码

def generate_mtf(pixel_aperture=1, azimuth=0, num_samples=128):
    ''' generates the 1D diffraction-limited MTF for a given pixel size and azimuth.

    Args:
        pixel_aperture (`float`): aperture of the pixel, in microns.  Pixel is
            assumed to be square.

        azimuth (`float`): azimuth to retrieve the MTF at, in degrees.

        num_samples (`int`): number of samples in the output array.

    Returns:
        `tuple` containing:
            `numpy.ndarray`: array of units, in cy/mm.

            `numpy.ndarray`: array of MTF values (rel. 1.0).

    Notes:
        Azimuth is not actually implemented yet.
    '''
    pitch_unit = pixel_aperture / 1e3
    normalized_frequencies = np.linspace(0, 2, num_samples)
    otf = np.sinc(normalized_frequencies)
    mtf = np.abs(otf)
    return normalized_frequencies / pitch_unit, mtf