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odak.learn.wave.produce_phase_only_slm_pattern

Definition for producing a pattern for a phase only Spatial Light Modulator (SLM) using a given field.

Parameters:

Name Type Description Default
hologram torch.cfloat

Input holographic field.

 required
slm_range float

Range of the phase only SLM in radians for a working wavelength (i.e. two pi). See odak.wave.adjust_phase_only_slm_range() for more.

 required
bits int

Quantization bits.

 8
default_range float

Default range of phase only SLM.

 6.28
illumination torch.tensor

Spatial illumination distribution.

 None

Returns:

Type Description
torch.cfloat

Adjusted phase only pattern.
Source code in odak/learn/wave/util.py 
def produce_phase_only_slm_pattern(hologram, slm_range, bits=8, default_range=6.28, illumination=None):
    """
    Definition for producing a pattern for a phase only Spatial Light Modulator (SLM) using a given field.

    Parameters
    ----------
    hologram           : torch.cfloat
                         Input holographic field.
    slm_range          : float
                         Range of the phase only SLM in radians for a working wavelength (i.e. two pi). See odak.wave.adjust_phase_only_slm_range() for more.
    bits               : int
                         Quantization bits.
    default_range      : float
                         Default range of phase only SLM.
    illumination       : torch.tensor
                         Spatial illumination distribution.

    Returns
    -------
    pattern            : torch.cfloat
                         Adjusted phase only pattern.
    hologram_digital   : np.int
                         Digital representation of the hologram.
    """
#    hologram_phase    = calculate_phase(hologram) % default_range
    hologram_phase = calculate_phase(hologram)
    hologram_phase = hologram_phase % slm_range
    hologram_phase /= slm_range
    hologram_phase *= 2**bits
    hologram_digital = hologram_phase.detach().clone()
    hologram_phase = torch.ceil(hologram_phase)
    hologram_phase *= slm_range/2**bits
    if type(illumination) == type(None):
        A = torch.tensor([1.]).to(hologram_phase.device)
    else:
        A = illumination
    return A*torch.cos(hologram_phase)+A*1j*torch.sin(hologram_phase), hologram_digital

Notes

Regarding usage of this definition, you can find use cases in the engineering notes, specifically at Optimizing holograms using Odak.

See also