An in situ holographic imaging system for marine studies

Abstract

The invention improves holographic imaging systems by being modular with deployment in a lens-less configuration or with a microscope objective, leading to a resolution range of 5.5 and to 0.5 μm/pixel, respectively, and resulting in a resolvable particle size range of several microns to a few cm between two setups. The invention includes variable sampling length between two windows (e.g., a sampling volume of 71.4 mL per hologram at 12 cm). Holograms are recorded with a 4920×3280 pixels digital camera. i.e., 15.3 MB per image, at a maximum rate of 3.2 Hz, such that free stream water sampling a 14 L/minute occurs. This is orders of magnitude higher than sampling of other imaging systems while including larger/variable sample volume, inclusion of copper shutters to prevent biofouling during long-term deployments, including deployment in different operation modes. No single previous system achieves all these things at the same time.

Dependencies are inferred from the claim text.