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Reflection phase imaging provides label-free, high-resolution characterization of biological samples, typically using interferometric-based techniques. Here, we investigate reflection phase microscopy fromintensity-only measurements under diverse illumination. We evaluate the forward and inverse scattering model based on the first Born approximation for imaging scattering objects above a glass slide. Under this design, the measured field combineslinearforward-scattering and height-dependentnonlinearback-scattering from the object that complicates object phase recovery. Using only the forward-scattering, we derive a linear inverse scattering model and evaluate this model’s validity range in simulation and experiment using a standard reflection microscope modified with a programmable light source. Our method provides enhanced contrast of thin, weakly scattering samples that complement transmission techniques. This model provides a promising development for creating simplified intensity-based reflection quantitative phase imaging systems easily adoptable for biological research.
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This content will become publicly available on November 13, 2025
Bright Ideas: Exploring Light Reflection and Sun Safety With Micro:Bits
https://www.teachengineering.org/activities/view/umo-2941-bright-ideas-light-reflection-microbits-activity Students engage in a hands-on exploration of vision and light reflection by creating a program that simulates light intensity and how our eyes perceive images using the LED display on the micro: bits and its radio feature. After creating a model of an eye, students simulate the light intensity and reflection processes before they work in groups to identify and solve real-world problems related to sunlight and vision. Students utilize the engineering design process to research, imagine, plan, create, test, and improve their solutions, such as reminders for when to wear sunglasses or sunscreen, displays of current sunlight intensity, or determining which materials block light/UV rays. This engineering curriculum aligns to Next Generation Science Standards (NGSS).
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- Award ID(s):
- 1801666
- PAR ID:
- 10560134
- Publisher / Repository:
- TeachEngineering.org
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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