Low-cost, high-speed near infrared reflectance confocal microscope

Area of Science:

• Biomedical optics
• Microscopy
• Medical imaging technology

Background:

• Smartphone-based confocal microscopy faces limitations in imaging depth and speed.
• Existing confocal microscopy techniques can be costly and complex for widespread use.

Purpose of the Study:

• To develop a low-cost, near-infrared reflectance confocal microscope (NIR RCM) for enhanced tissue imaging.
• To improve imaging depth and speed compared to previous smartphone-based systems.
• To maintain high lateral resolution with a cost-effective design.

Main Methods:

• Utilized an 840 nm superluminescent LED (sLED) as the light source for deeper tissue penetration.
• Engineered novel confocal detection optics to preserve lateral resolution with a larger slit width.
• Constructed the NIR RCM device with a material cost of approximately $5,200.

Main Results:

• Achieved a lateral resolution of 1.1 µm (vertical) and 1.3 µm (horizontal).
• Measured an axial resolution of 11.2 µm.
• Acquired *in vivo* confocal images of human forearm skin at 203 frames/sec, clearly showing epidermal and dermal cellular structures.

Conclusions:

• The developed NIR RCM offers a cost-effective solution for high-speed, deep-tissue imaging.
• This technology enables detailed visualization of cellular morphology in living human skin.
• The NIR RCM has potential applications in non-invasive skin diagnostics and research.