Refractive Fresnel liquid crystal lenses driven by two voltages

Area of Science:

• Optics
• Materials Science
• Electrical Engineering

Background:

• Liquid crystal (LC) lenses offer tunable optical properties.
• Achieving a precise parabolic phase profile in LC lenses is crucial for high performance.
• Existing designs often involve complex electrode structures.

Purpose of the Study:

• To propose and demonstrate a high-performance refractive Fresnel liquid crystal lens.
• To simplify the electrode design for efficient voltage distribution.
• To achieve a tunable parabolic phase profile using minimal driving voltages.

Main Methods:

• Designed a novel interconnected circular electrode structure for each Fresnel zone.
• Utilized two driving voltages to create a parabolic voltage distribution.
• Operated the liquid crystal material within its linear response region.
• Constructed and tested a four-zone Fresnel LC lens with an 8 mm aperture.

Main Results:

• Demonstrated a continuously adjustable optical power range from -1.30 D to +1.33 D.
• Confirmed the maintenance of a parabolic phase profile across Fresnel zones during electrical tuning.
• The simple electrode design enabled precise control over the phase profile.

Conclusions:

• The proposed refractive Fresnel LC lens exhibits high performance with a simplified electrode design.
• The lens provides excellent electrical tunability of optical power while preserving the desired parabolic phase profile.
• This technology holds promise for advanced optical systems requiring compact and reconfigurable lenses.