Development of low-cost, compact chiroptical imaging systems.

Area of Science:

• Chiroptical spectroscopy
• Materials science
• Optical physics

Background:

• Circular dichroism (CD) spectroscopy is crucial for analyzing chiral materials.
• Commercial CD spectrometers are expensive, bulky, and lack environmental control.
• There is a need for accessible and portable CD imaging systems.

Purpose of the Study:

• To develop novel, low-cost, and portable circular dichroism imaging systems.
• To enable spatial mapping of CD in chiral solid-state films.
• To facilitate in situ analysis of thermal processing effects on CD.

Main Methods:

• Utilized Fresnel rhombs as inexpensive broadband quarter-wave plates.
• Developed bespoke open-source control software for the imaging systems.
• Integrated systems with a temperature-controlled stage for in situ measurements.
• Cross-compared results with a Diamond Light Source CD imaging system.

Main Results:

• Demonstrated two novel, portable, and low-cost (<£2000) CD imaging systems.
• Successfully mapped the circular dichroism of chiral solid-state films with high spatial resolution (100 μm).
• Achieved high sensitivity (down to 250 mdeg) and good agreement with established systems.
• Identified optimal thermal processing conditions for maximizing CD in situ.

Conclusions:

• The developed CD imaging systems offer an affordable and portable alternative to commercial instruments.
• These systems are effective for spatially mapping CD and optimizing material processing.
• The technology advances the study of chiral materials, particularly in response to thermal stimuli.