Open Raman Microscope (ORM)
Schematic of the Open Raman Microscope with a single laser excitation
The Open Raman Microscope (ORM) is built on the Thorlabs Cerna modular microscope platform, enabling flexible and customizable optical configurations. This reference design demonstrates a high-throughput, confocal Raman microscope using 785 nm laser excitation. The system features a modular architecture with interchangeable filter cubes (similar to fluorescence microscopes) and supports both high-confocal 3D cellular imaging and rapid, high-throughput imaging.
Design
The epi detection microscope design is based on the coupling of laser into the microscope optical path of the objective. The backscattered Raman light is passed through a filter-cube and focused using a collimator onto an optical fiber acting as a confocal pinhole or a bundle to linear array of fibers (high-throughput). Scanning across a sample is performed by moving the stage in X, Y for a 2D scan, and along with Z for a 3D scan. These functions can be achieved by multiple possible components from various suppliers and the ORM construction and software control with ORM-IRIS has been designed to support this.
Software support
Control of the microscope has been realized in the open sourced software (ORM-IRIS available at https://github.com/The-Thomas-Lab-UCL/orm-iris) and adapts the universal .csv format as well as a space efficient SQLite3 database format compatible with Python, Fiji, Matlab and R. ORM-IRIS software supports the following hardware:
Spectrometers/CCD:
Stages/movement control:
Widefield cameras:
For control of the microscope the following PC configuration is recommended:
Windows 10
Intel i9 Processor
64 GB RAM (determines the maximum scan size)
Note: At present, the app is known to NOT work with MacOS* and is untested with Linux
*Specifically, the 'main controller' app to perform measurements are known to not operate well with the MacOS but, the 'main analyser' app designed to load the savefiles does behave relatively well in the MacOS, allowing users to still access their data with their preferred OS and outside the lab computer.
Notes on modularity and customization:
Design
The epi detection microscope design is based on the coupling of laser into the microscope optical path of the objective. The backscattered Raman light is passed through a filter-cube and focused using a collimator onto an optical fiber acting as a confocal pinhole or a bundle to linear array of fibers (high-throughput). Scanning across a sample is performed by moving the stage in X, Y for a 2D scan, and along with Z for a 3D scan. These functions can be achieved by multiple possible components from various suppliers and the ORM construction and software control with ORM-IRIS has been designed to support this.
Software support
Control of the microscope has been realized in the open sourced software (ORM-IRIS available at https://github.com/The-Thomas-Lab-UCL/orm-iris) and adapts the universal .csv format as well as a space efficient SQLite3 database format compatible with Python, Fiji, Matlab and R. ORM-IRIS software supports the following hardware:
Spectrometers/CCD:
- Ocean Optics spectrometers (QEPro Raman lines)
- Princeton Instruments (Teledyne) (PIXIS families)
- Andor - Oxford Instruments (Ibsen EAGLE Raman S, Wasatch's Andor based cameras, etc.)
- Wasatch spectrometers
Stages/movement control:
- Physik Instrumente
- Zaber Technologies
- Thorlabs (Kinesis-based XY and Z stages; e.g., PFM450, M30XY, Z825B, etc.)
- Thorlabs MCM301 compatible Z stages
Widefield cameras:
- Thorlabs Scientific cameras (monochrome and color)
- Webcams
For control of the microscope the following PC configuration is recommended:
Windows 10
Intel i9 Processor
64 GB RAM (determines the maximum scan size)
Note: At present, the app is known to NOT work with MacOS* and is untested with Linux
*Specifically, the 'main controller' app to perform measurements are known to not operate well with the MacOS but, the 'main analyser' app designed to load the savefiles does behave relatively well in the MacOS, allowing users to still access their data with their preferred OS and outside the lab computer.
Notes on modularity and customization:
- Any laser from the UV to NIR can be implemented given filters/lenses are compatible with the wavelength range.
- Ensure that the laser is beam expanded to fill the back aperture of the microscope objective
- The spectrometer configuration should match the laser excitation accordingly. For instance, for a 532 nm visible laser the Raman grade spectrometer can cover from 570 nm to 700 nm corresponding to 400cm-1 to 3600 cm-1