CoMakingSpace Wiki - User Contributions [en]

Project:Digital Holographic Miocroscope

2024-01-18T12:39:12Z

Lennart:

{{ProjectInfoBox
|project title=Digital Holographic Microscope
|image=Holmos setup comakingspace.jpeg
|status=being built
|date=
|initiator=Patrick, Lennart
|team=
|materials=
|tools=
|software=
|cost=
}}

=== Introduction ===

==== Holmos ====
This project is based on project Holmos (https://github.com/holmos-ipm) by Fraunhofer IPM.

==== Digital Holographic Microscopy ====
Wikipedia https://en.wikipedia.org/wiki/Digital_holographic_microscopy

This file explains the constraints in optical adjustment https://github.com/holmos-ipm/holmos-hardware/blob/master/instructions/optics_design.md

=== Assembly ===
Mounts for the optical components can be printed from files provided in the project repo. These can then be axially moved on metal beams. A Raspberry Pi camera is used for imaging. It is connected to a Raspberry Pi that performs the phase image reconstruction.
[[File:Holmos objective mount stl.png|thumb|139x139px|Several components can be 3D-printed either from ready-to-use STL files or 3D files generated with Solidpython ]]

=== Usage ===
Key steps are

# Position the components according to https://github.com/holmos-ipm/holmos-hardware/blob/master/reference_assembly.py
# Adjust slide holder or objective to get a focused image from the objective beam only
# Direct the reference beam onto the camera sensor

Further practical instructions are given in https://github.com/holmos-ipm/holmos-hardware/blob/master/instructions/adjustment.md

In the Holmos Fourier amplitude view, the first diffraction order is selected as ROI. Then, the captured ("wrapped") phase image is saved on the hard drive. In a separate application, this image is then "unwrapped", e.g. black to white jumps due to the restricted value range of -π to π are removed.
[[File:Holmos emulator.jpg|thumb|363x363px|Fourier amplitude view in the Holmos UI. The blue rectangle is moved to encompass the first diffraction order and surrounding frequences stemming from the interference of the reference beam and light passing the sample.|none]]

=== Results ===
<gallery widths="140" heights="140" perrow="2" caption="Quantitative phase image reconstructed from a cheek cell hologram.">
File:Holmos cheek interference.png|Interference image captured by the camera
File:Holmos cheek fft.png|Fourier amplitude in which the information of interest is encoded in the frequencies around the first diffraction order
File:Holmos cheek wrapped.png|Wrapped phase image reconstructed from the ROI in the Fast Fourier Transform
File:Holmos cheek unwrapped.png|Unwrapped phase image
</gallery>

=== Challenges ===

Project:Digital Holographic Miocroscope

2024-01-18T12:38:46Z

Lennart: Add results gallery

{{ProjectInfoBox
|project title=Digital Holographic Microscope
|image=Holmos setup comakingspace.jpeg
|status=being built
|date=
|initiator=Patrick, Lennart
|team=
|materials=
|tools=
|software=
|cost=
}}

=== Introduction ===

==== Holmos ====
This project is based on project Holmos (https://github.com/holmos-ipm) by Fraunhofer IPM.

==== Digital Holographic Microscopy ====
Wikipedia https://en.wikipedia.org/wiki/Digital_holographic_microscopy

This file explains the constraints in optical adjustment https://github.com/holmos-ipm/holmos-hardware/blob/master/instructions/optics_design.md

=== Assembly ===
Mounts for the optical components can be printed from files provided in the project repo. These can then be axially moved on metal beams. A Raspberry Pi camera is used for imaging. It is connected to a Raspberry Pi that performs the phase image reconstruction.
[[File:Holmos objective mount stl.png|thumb|139x139px|Several components can be 3D-printed either from ready-to-use STL files or 3D files generated with Solidpython ]]

=== Usage ===
Key steps are

# Position the components according to https://github.com/holmos-ipm/holmos-hardware/blob/master/reference_assembly.py
# Adjust slide holder or objective to get a focused image from the objective beam only
# Direct the reference beam onto the camera sensor

Further practical instructions are given in https://github.com/holmos-ipm/holmos-hardware/blob/master/instructions/adjustment.md

In the Holmos Fourier amplitude view, the first diffraction order is selected as ROI. Then, the captured ("wrapped") phase image is saved on the hard drive. In a separate application, this image is then "unwrapped", e.g. black to white jumps due to the restricted value range of -π to π are removed.
[[File:Holmos emulator.jpg|thumb|363x363px|Fourier amplitude view in the Holmos UI. The blue rectangle is moved to encompass the first diffraction order and surrounding frequences stemming from the interference of the reference beam and light passing the sample.|none]]

=== Results ===
<gallery widths="140" heights="140" perrow="3" caption="Quantitative phase image reconstructed from a cheek cell hologram.">
File:Holmos cheek interference.png|Interference image captured by the camera
File:Holmos cheek fft.png|Fourier amplitude in which the information of interest is encoded in the frequencies around the first diffraction order
File:Holmos cheek wrapped.png|Wrapped phase image reconstructed from the ROI in the Fast Fourier Transform
File:Holmos cheek unwrapped.png|Unwrapped phase image
</gallery>

=== Challenges ===

Project:Digital Holographic Miocroscope

2024-01-18T12:26:25Z

Lennart: add intro, assembly, usage

File:Holmos cheek unwrapped.png

2024-01-18T12:25:45Z

Lennart:

File:Holmos cheek fft.png

2024-01-18T12:25:29Z

Lennart:

File:Holmos cheek interference.png

2024-01-18T12:25:03Z

Lennart:

File:Holmos cheek wrapped.png

2024-01-18T12:23:03Z

Lennart:

File:Holmos emulator.jpg

2024-01-18T12:14:01Z

Lennart:

Fourier amplitude of a hologram as displayed in the Holmos UI.

File:Holmos objective mount stl.png

2024-01-18T11:56:53Z

Lennart:

screenshot of Holmos objective mount STL loaded into onshape

Project:Digital Holographic Miocroscope

2024-01-18T10:47:03Z

Lennart: upload project photo

File:Holmos setup comakingspace.jpeg

2024-01-18T10:46:14Z

Lennart:

Lennart

2023-10-04T18:18:32Z

Lennart: created redirect for user page

#REDIRECT [[User:Lennart]]

User:Lennart

2023-10-04T18:18:32Z

Lennart: create user page