Measurement of the point-spread function in a layered system.

Area of Science:

• Optical physics
• Fluid dynamics
• Imaging science

Background:

• Accurate characterization of light scattering in water is crucial for applications like underwater imaging and remote sensing.
• The point-spread function (PSF) quantifies image blurring due to scattering.
• Existing methods may not fully capture the impact of scattering layer location.

Purpose of the Study:

• To describe a novel laboratory facility for measuring the point-spread function (PSF) of water.
• To investigate the influence of scattering layer position on the PSF.
• To quantify how different optical path lengths affect light diffusion in water.

Main Methods:

• Utilized a laboratory setup with a Lambertian light source and a camera focused at infinity.
• Measured the PSF of water with integrated scattering layers.
• Varied the optical path length and positioned the scattering layer near the source, near the camera, and intermediately.

Main Results:

• The PSF of water is highly sensitive to the scattering layer's position.
• For identical optical path lengths, a scattering layer positioned near the camera resulted in the most diffuse PSF.
• The spatial distribution of scattered light is significantly altered by layer placement.

Conclusions:

• The location of scattering layers critically impacts the point-spread function in aqueous media.
• The developed facility provides a robust method for characterizing light diffusion in scattering media.
• Findings are relevant for optimizing optical systems operating in turbid water environments.