Analysis of a vertical-cavity surface-emitting laser-based bidirectional free-space optical interconnect.

Area of Science:

• Optoelectronics
• Photonics
• Optical Engineering

Background:

• Free-space optical interconnects offer high bandwidth potential.
• Vertical-cavity surface-emitting lasers (VCSELs) are suitable coherent light sources.
• Holographic optical elements are key components in free-space systems.

Purpose of the Study:

• To design and analyze a bidirectional free-space optical interconnect system.
• To investigate the use of VCSEL arrays and holographic elements.
• To develop an optical model for system parameter optimization.

Main Methods:

• Utilized VCSEL arrays for coherent light generation and beam collimation.
• Designed hologram arrays using a photopolymer copying technique to enhance diffraction efficiency.
• Measured hologram scattering as a noise source.
• Developed an optical model based on cross-talk analysis to determine system parameters (VCSEL beam diameter, hologram size/apodization, detector size).
• Analyzed the impact of VCSEL wavelength variation and calculated Fourier lens aberrations.

Main Results:

• A design methodology for a bidirectional free-space optical interconnect system is presented.
• The study quantifies scattering from holograms as a noise source.
• An optical model provides a basis for optimizing system parameters.
• The effects of VCSEL wavelength variation and lens aberrations are considered.

Conclusions:

• The presented design and analysis provide a framework for developing efficient free-space optical interconnects.
• Optimization of system parameters based on cross-talk analysis is crucial.
• Addressing noise sources like hologram scattering and lens aberrations is necessary for system performance.