pado.optical_element.DOE¶

class DOE(dim, pitch, material, wvl, device, height=None, phase_change=None, polar='non')[source]¶

Parameters:

dim (tuple)
pitch (float)
material (Material)
wvl (float)
device (str)
height (Tensor | None)
phase_change (Tensor | None)
polar (str)

__init__(dim, pitch, material, wvl, device, height=None, phase_change=None, polar='non')[source]¶

Diffractive optical element (DOE) that modifies incident light wavefront.

The wavefront modification is determined by the material height profile. Supports both height and phase change specifications.

Parameters:

dim (tuple) – Dimensions (B, 1, R, C) for batch size, channels, rows, columns
pitch (float) – Pixel pitch in meters
material (Material) – Material properties of the DOE
wvl (float) – Wavelength of light in meters
device (str) – Device to store wavefront (‘cpu’, ‘cuda:0’, etc.)
height (torch.Tensor, optional) – Height profile in meters
phase_change (torch.Tensor, optional) – Phase change profile
polar (str) – Polarization mode (‘non’: scalar, ‘polar’: vector)

Examples

>>> # Create DOE with specified height profile
>>> height = torch.ones((1,1,100,100)) * 500e-9  # 500nm height
>>> doe = DOE(height.shape, 2e-6, material, 500e-9, 'cpu', height=height)

>>> # Create DOE with specified phase profile
>>> phase = torch.ones((1,1,100,100)) * np.pi  # π phase
>>> doe = DOE(phase.shape, 2e-6, material, 500e-9, 'cpu', phase_change=phase)

visualize(b=0, c=0)[source]¶

Visualize the DOE wavefront modulation.

Displays amplitude change, phase change and height profile.

Parameters:

b (int) – Batch index to visualize, defaults to 0
c (int) – Channel index to visualize, defaults to 0

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.visualize()  # Shows modulation plots
>>> doe.visualize(b=1, c=0)  # Shows plots for batch index 1

set_diffraction_grating_1d(slit_width, minh, maxh)[source]¶

Set the wavefront modulation as a 1D diffraction grating.

Create alternating height regions to form a binary phase grating.

Parameters:

slit_width (float) – Width of each slit in meters
minh (float) – Minimum height in meters
maxh (float) – Maximum height in meters

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_diffraction_grating_1d(10e-6, 0, 500e-9)  # 10μm slits
>>> doe.visualize()  # Shows 1D grating pattern

set_diffraction_grating_2d(slit_width, minh, maxh)[source]¶

Set the wavefront modulation as a 2D diffraction grating.

Create a checkerboard pattern of alternating height regions.

Parameters:

slit_width (float) – Width of each slit in meters
minh (float) – Minimum height in meters
maxh (float) – Maximum height in meters

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_diffraction_grating_2d(10e-6, 0, 500e-9)  # 10μm slits
>>> doe.visualize()  # Shows 2D grating pattern

set_Fresnel_lens(focal_length, wvl, shift_x=0, shift_y=0)[source]¶

Set the wavefront modulation as a Fresnel lens.

Create a phase profile that focus light to a point.

Parameters:

focal_length (float) – Focal length in meters
wvl (float) – Wavelength in meters
shift_x (float) – Horizontal shift in meters. Defaults to 0
shift_y (float) – Vertical shift in meters. Defaults to 0

Return type:

None

Examples

>>> doe = DOE((1,1,1024,1024), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_Fresnel_lens(0.1, 500e-9)  # f=10cm lens
>>> doe.set_Fresnel_lens(0.1, 500e-9, shift_x=50e-6)  # Shifted lens

set_Fresnel_zone_plate_lens(focal_length, wvl, shift_x=0, shift_y=0)[source]¶

Set binary Fresnel zone plate pattern.

Creates alternating opaque and transparent zones that focus light.

Parameters:

focal_length (float) – Focal length in meters
wvl (float) – Wavelength in meters
shift_x (float) – Horizontal shift in meters. Defaults to 0
shift_y (float) – Vertical shift in meters. Defaults to 0

Return type:

None

Examples

>>> doe = DOE((1,1,1024,1024), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_Fresnel_zone_plate_lens(0.1, 500e-9)  # f=10cm lens
>>> doe.set_Fresnel_zone_plate_lens(0.1, 500e-9, shift_x=50e-6)  # Shifted lens

change_wvl(wvl)[source]¶

Change the wavelength and update phase change.

Parameters:: wvl (float) – New wavelength in meters
Return type:: None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.change_wvl(633e-9)  # Change to 633nm wavelength

sync_height_with_phase()[source]¶

Synchronize height profile with current phase profile. :rtype: None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_phase_change(phase, sync_height=False)
>>> doe.sync_height_with_phase()  # Update height to match phase

Return type:: None

sync_phase_with_height()[source]¶

Synchronize phase profile with current height profile. :rtype: None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.set_height(height, sync_phase=False)
>>> doe.sync_phase_with_height()  # Update phase to match height

Return type:: None

resize(target_pitch)[source]¶

Resize DOE with a new pixel pitch.

Resize field from which DOE height is recomputed.

Parameters:: target_pitch (float) – New pixel pitch in meters
Return type:: None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> doe.resize(1e-6)  # Change pitch to 1μm

get_height()[source]¶

Return the height map of the DOE.

Returns:: Height map in meters
Return type:: torch.Tensor

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> height = doe.get_height()  # Get current height profile

set_phase_change(phase_change, sync_height=True)[source]¶

Set phase change induced by the DOE.

Parameters:

phase_change (torch.Tensor) – Phase change profile
sync_height (bool) – If True, syncs height profile

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> phase = torch.ones((1,1,100,100)) * np.pi
>>> doe.set_phase_change(phase, sync_height=True)

set_field_change(field_change, sync_height=True)[source]¶

Change the field change of the DOE.

Parameters:

field_change (torch.Tensor) – Complex field change tensor
sync_height (bool) – If True, syncs height profile

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> field = torch.exp(1j * torch.ones((1,1,100,100)))
>>> doe.set_field_change(field, sync_height=True)

set_height(height, sync_phase=True)[source]¶

Set the height map of the DOE.

Parameters:

height (torch.Tensor) – Height map in meters
sync_phase (bool) – If True, syncs phase profile

Return type:

None

Examples

>>> doe = DOE((1,1,100,100), 2e-6, material, 500e-9, 'cpu')
>>> height = torch.ones((1,1,100,100)) * 500e-9
>>> doe.set_height(height, sync_phase=True)