Building a backlight unit with lateral gate structure based on carbon nanotube field emitters

Area of Science:

• Materials Science
• Electronics Engineering
• Physics

Background:

• Liquid crystal displays (LCDs) require efficient backlight units.
• Carbon nanotube field emitters offer potential for advanced display technologies.

Purpose of the Study:

• To fabricate and optimize a backlight unit for LCDs using printed carbon nanotube field emitters.
• To investigate the impact of device architecture on field emission characteristics.
• To enhance the efficiency and luminance of the backlight unit.

Main Methods:

• Fabrication of a backlight unit with printed carbon nanotube field emitters, lateral gate, and mesh structures.
• Optimization of device architecture through field emission characterization.
• Numerical simulation to support experimental findings.
• Evaluation of performance using phosphor screens and measurements of efficiency and luminance.

Main Results:

• Emission current is highly dependent on cathode-gate gap, mesh position, and mesh bias.
• Electron beam shrinkage along the lateral direction was observed with increasing anode bias, consistent with simulations.
• A modified structure with double emitter edges achieved approximately 20% higher phosphor efficiency (34.4 lm W⁻¹) and luminance (9600 cd m⁻²).

Conclusions:

• The optimized backlight unit design, particularly the double emitter edge structure, significantly enhances performance.
• Printed carbon nanotube field emitters are a viable technology for high-efficiency and high-luminance display backlights.