[A Simple but Effective Device to Avoid Objective Lens Overheating: An Air Blower Device].

Area of Science:

• Geophysics and mineral physics
• Spectroscopy and material science

Background:

• Earth's interior is characterized by high temperatures and pressures, significantly affecting mineral properties.
• Vibrational spectroscopy, including infrared and Raman, is crucial for studying these high-temperature mineralogical changes.
• Conventional high-temperature spectroscopy is limited by heating device radiation damaging the objective lens.

Purpose of the Study:

• To develop a method for exceeding current instrumental temperature limits in spectroscopy.
• To enable in situ spectroscopic analysis of minerals at higher temperatures than previously possible.

Main Methods:

• Implemented a simple air blower system to create a forced convective gas flow around the objective lens.
• Utilized turbulent gas flow to enhance heat transport away from the objective lens, preventing overheating.
• Performed in situ high-temperature Raman spectroscopy on forsterite samples.

Main Results:

• The air blower system effectively reduced objective lens temperature from ~235°C to ~68°C at a sample temperature of 1000°C.
• Successfully conducted in situ Raman spectroscopy up to 1300°C without damaging the objective lens.
• Achieved high-temperature measurements without requiring expensive specialized optics.

Conclusions:

• The developed air blower method is a simple yet highly effective solution for high-temperature spectroscopy.
• This technique significantly extends the accessible temperature range for in situ vibrational spectroscopy of minerals.
• Enables advanced research into Earth's deep interior conditions using Raman spectroscopy.