Research on the design of an optical information storage sensing system using a diffractive optical element

Area of Science:

• Optics
• Nanotechnology
• Data Storage

Background:

• Traditional optical systems often require multiple lasers and lenses for complex tasks.
• Existing data storage and sensing technologies face limitations in miniaturization and efficiency.

Purpose of the Study:

• To develop a compact optical system integrating information storage and sensing capabilities.
• To demonstrate the utility of a diffractive optical element (DOE) for simplifying optical path management.

Main Methods:

• A novel optical system design utilizing a single femtosecond laser and one objective lens.
• Integration of a diffractive optical element (DOE) to separate recording-reading and servo beams.
• Characterization of the optical system's linear region, wavefront error, and DOE fabrication parameters.

Main Results:

• The system successfully integrates longitudinal surface plasmon resonance detection of gold nanorods with data storage.
• The DOE enables a single optical path for multiple beam types, compatible with DVD servo modules (8 λ linear region).
• Achieved wavefront error below 0.03 λ(rms) and fabricated DOE with a 13.4 µm grating period and 1.2 µm depth.

Conclusions:

• The developed compact optical system offers a versatile platform for advanced sensing and high-density data storage.
• The DOE design facilitates efficient layer selection with a linear displacement-distance correlation.
• Experimental verification confirms the system's performance and potential for practical applications.